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Animal waste can contribute substantially to nutrient cycling and ecosystem productivity in many environments. However, little is known of the biogeochemical impact of animal excretion in wetland habitats. Here we investigate the effects of wood frog (Lithobates sylvaticus) tadpole aggregations on nutrient recycling, microbial metabolism and carbon cycling in geographically isolated wetlands. We used a paired mesocosm and field study approach that utilized measurements of tadpole excretion rates, microbial extracellular enzyme activities, and litter degradation. We found a strong relationship between tadpole development and nutrient excretion, demonstrating that ontological changes impact tadpole‐mediated nutrient cycling in wetland habitats. Further, the interplay between population‐level tadpole excretion and wetland hydrologic conditions increased ambient NH4+$$ {\mathrm{NH}}_4^{+} $$ and PO43−$$ {\mathrm{PO}}_4^{3-} $$ concentrations by 56 and 14 times, respectively, compared to adjacent wetlands without tadpoles. Within our mesocosm study, microbes decreased extracellular enzyme production associated with nitrogen acquisition in response to the presence of tadpole‐derived nitrogen. In addition to microbial metabolic responses, tadpole presence enhanced litter breakdown in both mesocosms and wetlands by 7% and 12%, respectively, in comparison to reference conditions. These results provide evidence for the functional and biogeochemical role of tadpole aggregations in wetland habitats, with important implications for ecosystem processes, biodiversity conservation, and ecosystem management. [ABSTRACT FROM AUTHOR]

Cropland (CRL) abandonment is a worldwide phenomenon of land use change with significant impacts on agro‐ecosystems. This research attempts to deepen the analysis of the positive and negative effects arising by focusing on the changes in soil properties and the amount and composition of soil particles detached after several periods of rainfall and the resulting exported sediment that occurs in abandoned areas with natural revegetation compared to CRL. The study was carried out in an agroforestry catchment with a temperate climate, on which CRL and abandoned land with natural vegetation were compared. The soil was sampled along two representative hillslopes integrating elements of the landscape and land use/land covers. Sediments were collected after seven periods in which flood events were recorded during the period July 2016 to December 2017, using artificial‐lawn mats. Soil and sediment composition (texture, soil organic carbon [SOC] and nutrients [total nitrogen and total phosphorous]) under both land uses were assessed and compared and related to rainfall characteristics using principal component analysis. Nutrient enrichment factors in the sediments compared to soils were also evaluated. The results highlight that after abandonment, SOC increased significantly, reaching contents almost three times higher than in CRL. Consequently, soil erodibility decreased, resulting in substantially lower sediment generation after erosive rainfall events. On average, sediment generation was three times lower in abandoned areas than in CRL, despite their steeper slopes. Soil total nitrogen also increased on abandoned lands, reaching values about twice as high as those in CRL. However, total phosphorous content was almost twice as high in CRL than in abandoned land posing a potential risk for water due to higher erosion rates recorded in CRL. The results confirmed the association of phosphorous with smaller particles and also demonstrated the total phosphorous‐SOC link in abandoned land. Furthermore, the effect of rainfall intensity on phosphorous mobilisation was confirmed, whilst nitrogen losses were mainly related to the total amount of rainfall recorded. In a scenario of increasing extreme precipitation, both total amount and increased precipitation intensity may exacerbate water pollution problems following nutrient loss in cultivated areas. This research contributes to identifying the impacts on agroforestry systems within the current context of converting natural areas into cultivated land, whilst in other regions revegetated natural areas are developed from abandoned agricultural land. [ABSTRACT FROM AUTHOR]

Attapulgite (ATP) is a biocompatible clay mineral that efficiently absorbs water. It is widely used in water treatment due to its environmental friendliness and cost‐effectiveness. This study aimed to develop a volume‐expansion structure‐based attapulgite flocculant (VES‐ATP) using aluminum salt and attapulgite (ATP) under alkaline conditions, specifically for the treatment of water containing low levels of phosphorus. The VES‐ATP was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X‐ray diffraction, and X‐ray photoelectron spectroscopy. The removal of phosphorus by the VES‐ATP was conducted by varying the mass ratio of Al to attapulgite (denoted as RmAl/mATP), ATP dosage, and pH. The results showed that the VES‐ATP had a good expansion and dispersibility in the presence of alkalized aluminum species. The basicity as the molar ratio of OH to Al (0.8 or 1.6) determined the expansion feasibility, and the coverage degree of Al onto ATP, as indicated by the mass ratio of Al to attapulgite (denoted as RmAl/mATP), determined Al flocculation efficiency. Higher values such as RmAl/mATP = 4:1 and 2:1 may result in a better flocculation. Low phosphorus treatment was successfully achieved through Al flocculation and ATP adsorption, including complexation, hydrogen bonding, and electrostatic attraction. As expected, the VES‐ATP generated larger size flocs with a bigger fractal dimension than that with the sole Al flocculation. As a result, the total phosphorus could be reduced to the level below 5 μg/L. It is more efficient in the pH range of 5–9. Overall, the coupling of aluminum and attapulgite has significantly enhanced both purification capabilities of phosphorus. Practitioner Points: Polymeric aluminum‐modified attapulgite was efficient for removal of low phosphorus concentration.Phosphorus concentrations can be reduced to below 5 μg/L.Polymeric aluminum and attapulgite are both safe, and this technology is suitable for water treatment. [ABSTRACT FROM AUTHOR]

Chronic kidney disease‐mineral bone disorder (CKD‐MBD) is a syndrome commonly observed in subjects with impaired renal function. Phosphate metabolism has been implicated in the pathogenesis of CKD‐MBD and according to the phosphorocentric hypothesis may be the key player in the pathogenesis of these abnormalities. As phosphorous is an essential component for life, absorption from the bowel, accumulation and release from the bones, and elimination through the kidneys are all homeostatic mechanisms that maintain phosphate balance through very sophisticated feedback mechanisms, which comprise as main actors: vitamin D (VD), parathyroid hormone (PTH), calciproteins particles (CPPs), fibroblast growth factor‐23 (FGF‐23) and other phosphatonins and klotho. Indeed, as the renal function declines, factors such as FGF‐23 and PTH prevent phosphate accumulation and hyperphosphatemia. However, these factors per se may be responsible for the organ damages associated with CKD‐MBD, such as bone osteodystrophy and vascular calcification. We herein review the current understanding of the CKD‐MBD focusing on phosphorous metabolism and the impact of phosphate manipulation on surrogate and hard outcomes. [ABSTRACT FROM AUTHOR]

Horticultural peat extraction can mobilize dissolved organic matter (DOM) and inorganic nutrients (nitrogen and phosphorous) to surface waters, harming aquatic ecosystems and water quality. However, it is uncertain how peat extraction affects solute concentration across hydrological and seasonal conditions and how biogeochemical processing in downstream drainage networks responds. Over two years, we used repeated, spatially extensive sampling in stream networks of two mixed land‐use catchments (<200 km2) on the subhumid interior plains of western Canada. We used random forest models to disentangle the effects of land cover, hydrology, and temperature on water chemistry. Peatlands were the dominant source of DOM to streams, but we detected no substantial effect of peat extraction on DOM concentration or composition. Stream discharge was the most important predictor of DOM composition, with generally humic‐like DOM becoming fresher during snowmelt and summer base flow. We detected no effect from peat extraction on soluble reactive phosphorous (SRP) or nitrate (NO3−). However, total ammonia nitrogen (TAN) was an order of magnitude higher in subcatchments with >40% extracted peatland cover (median: 1.5 mg TAN L−1) compared to catchments with similar intact peatland cover. Mass balance analysis suggested that DOM and inorganic nutrients synchronously attenuated during low flows. During high flows, DOM and inorganic nitrogen were conservatively transported, while SRP was attenuated, likely sorbing to suspended particles. Our study suggests that excess TAN mobilized by peat extraction is utilized in headwaters during low flow but propagates downstream during high flow, with implications for eutrophication that land managers should consider. Key Points: Peat extraction in a subhumid continental climate significantly increased stream ammonia concentration, but not carbon or phosphorusStream hydrology strongly influenced dissolved organic matter (DOM) composition, with low flows shifting DOM from aromatic to aliphaticHydrology affected the downstream persistence of DOM and nitrogen, which attenuated at low flows. Phosphorus was attenuated at all flows [ABSTRACT FROM AUTHOR]

A general approach to the direct deoxygenative transformation of primary, secondary, and tertiary alcohols has been developed. It undergoes through phosphoranyl radical intermediates generated by the addition of exogenous iodine radical to trivalent alkoxylphosphanes. Since these alkoxylphosphanes are readily in situ obtained from alcohols and commercially available, inexpensive chlorodiphenylphosphine, a diverse range of alcohols with various functional groups can be utilized to proceed deoxygenative cross‐couplings with alkenes or aryl iodides. The selective transformation of polyhydroxy substrates and the rapid synthesis of complex organic molecules are also demonstrated with this method. [ABSTRACT FROM AUTHOR]

The effects of calcium phosphate (CaP) materials on macrophage polarization state vary with their physicochemical properties. The study aims to elucidate the impact of phosphate ion‐mediated energy metabolism on M2 macrophage polarization and the corresponding regulatory mechanism. The phosphate ions released from CaP ceramic as bioenergetic factor is identified; its concentration is closely associated with the polarized state. After being taken up by the sodium‐dependent phosphate transporter 1, extracellular phosphate ions produce energy via oxidative phosphorylation by facilitating tricarboxylic acid flux, thereby contributing to M2 macrophage polarization. Further mechanistic analysis reveals that the elevation of the bioenergetic basis can drive macrophage M2 polarization via the AMP‐activated protein kinase‐mammalian target of rapamycin (AMPK‐mTOR) axis. Another regulatory effect is that of the adenosine triphosphate (ATP), a signaling molecule. Intracellular ATP is released into the extracellular space and degraded to adenosine, which serves as a signaling molecule through the A2b adenosine receptor to activate the cyclic adenosine monophosphate (cAMP) pathway, thereby promoting M2 macrophage polarization. Overall, these findings may transform the existing knowledge on cell metabolism and energy homeostasis from bystanders to pivotal factors guiding M2 macrophage polarization and have implications for the future design of biomimetic CaP scaffolds. [ABSTRACT FROM AUTHOR]

Background: Farmers need information regarding soil fertility at every location of their fields to attain a higher level of precision in nutrient management. Nonetheless, the acquisition and processing of soil samples are labor‐intensive and time‐utilizing, and the related cost remains high‐priced to farmers. Artificial intelligence is the most speedily growing area combined into approximately all aspects of human life. Soil macronutrients like nitrogen (N), phosphorous (P), and potassium (K) have a significant role in precision agriculture. There is a huge need for powerful and rapid measurement systems to measure accurately the macronutrients in the soil for optimal crop productivity, especially in site‐specific crop management system, where the application of fertilizer can be regulated spatially with respect to crop demand. Nevertheless, it can present a research direction to design an advanced scheme in order to predict the properties of soil. A portable sensor device is a basic need of an agriculture system for the accurate and rapid monitoring of soil macronutrients. Aim: In this research, the soil nutrients identified from the collected soil samples using optical sensors are evaluated for their accuracy using a deep learning approach. Methods: A deep residual network is exploited for the soil nutrient prediction after augmenting the gathered soil data. Finally, various performance evaluation measures, like mean squared error (MSE), mean absolute error (MAE), and root mean squared error (RMSE), are calculated to detect how accurately the sensor predicted the soil nutrients. Results: From the experimental analysis, it is stated that the proposed model attained low MSE value of 4.59 e−09, the low RMSE value of 6.78 e−05, and the low MAE value of 4.66 e−05 for N prediction. Likewise, the proposed model attained the least MSE value of 1.41 e−05, the least RMSE value of 0.0003, and the least MAE value of 0.0001 for P prediction. Conclusion: Finally, for K prediction, the proposed model achieved the least MSE value of 1.54 e−06, least RMSE value of 1.24 e−03, and the least MAE value of 1.38 e−05. [ABSTRACT FROM AUTHOR]

A phosphorous‐containing benzoxazine, (3‐(4‐hydroxyphenyl)‐3,4‐dihydro‐2H‐benzo[e][1,3]oxazin‐4‐yl)diphenylphosphine oxide (DPOBH), was synthesized and used as flame retardant and co‐curing agent in the presence of 4,4′‐diaminodiphenylsulfone (DDS) for diglycidyl ether of bisphenol‐A (DGEBA) epoxy resin. The flame retardancy, thermal stability, Tg, dielectric properties, and water absorption properties of epoxy resins (EP) were investigated and compared. The incorporation of DPOBH results in ca. 40%–45% increase of limiting oxygen index (LOI) values. UL‐94 V‐0 rating could be achieved for EP/DPOBH1.2 sample with the LOI value of 35.1%. Compared with EP, ca. 47% decrease of peak heat release rate (PHRR) could be obtained for EP/DPOBH1.2. According to the results of cone calorimetry tests (CCT), DPOBH could play roles in both gas and condensed phases. Moreover, the incorporation of DPOBH could reduce the water absorption rate, dielectric constant, and dielectric loss. All results suggest that DPOBH is a type of flame retardant suitable for EP used in electronic fields. [ABSTRACT FROM AUTHOR]

Understanding how invasive species respond to changes in abiotic factors and what influences their ability to colonise newly disturbed areas is necessary to predict species expansion, prioritise management efforts, and develop ecological models. We conducted a fully factorial greenhouse experiment using rhizome fragments to examine the effects of four nutrients levels, three soil moisture levels, and two light levels (with five replicates, n = 120) on the growth and resource allocation patterns of Arundo donax, a large‐statured invasive wetland species. We predicted that A. donax's performance‐related traits—traits that directly influence the functionality and fitness of an individual—such as aboveground biomass (AGB), belowground biomass (BGB), net photosynthesis, and average stem height, would be highest under high light, high soil moisture and high nutrient conditions due to the ability of aggressive invasive species to capitalise on greater resource availability. Analyses using general linear mixed‐effects models revealed significant interactions between soil moisture and light. Plants grown in saturated, high light conditions exhibited the highest values for performance‐related traits. However, contrary to predictions, nutrients did not significantly influence these traits. Multivariate analysis of variance demonstrated that nutrients did influence biomass allocation patterns, with plants grown with added nitrogen and phosphorus displaying higher AGB:BGB and stem:leaf ratios. This research highlights A. donax's unique response to nutrient addition and the plasticity of biomass allocation patterns. By understanding how invasive species respond to common abiotic factors, we can better predict their expansion and prioritise management efforts, such as focusing on areas of low overstory shading, while also providing crucial information for ecological model development. [ABSTRACT FROM AUTHOR]

The mid‐Proterozoic (∼1.8–0.8 Ga) ocean‐atmosphere system is hypothesized to have experienced fluctuations in redox conditions with transient oxygenation events. One of these happened at ∼1.4 Ga, and it is speculated that this event may link to the emplacement of large igneous province (LIP) at this time. However, direct evidence for this relationship remains to be proved. Here, we report Hg/TOC, P, and trace element concentrations across the ∼1.4 Ga oxygenation event in the Xiamaling Formation of North China. A prominent increase in Hg/TOC is slightly earlier than that of nutrient contents (especially P), pyrite and TOC abundances, suggesting that this distinct oxygenation event was likely the result of LIP activity at ∼1.4 Ga, which increased nutrient and sulfate supply from continental weathering to the ocean, sustaining elevated primary productivity, organic carbon and pyrite burial. This study indicates that LIP weathering could trigger transient oxygenation events during the mid‐Proterozoic. Plain Language Summary: The mid‐Proterozoic (∼1.8–0.8 Ga) retains persistent low oxygen concentrations in atmosphere and shallow seawater but is occasionally punctuated by transient oxygenation events. Multiple lines of evidence from sedimentary geochemistry have argued a global oxygenation event at ∼1.4 Ga, and speculated that this event was closely related to large igneous province (LIP) activity at this time. Direct link between LIP activity and the oxygenation event, however, has rarely been addressed yet. As mercury in sedimentary rocks has been widely used to trace volcanism, we therefore report Hg/TOC, P, and trace element concentrations across the ∼1.4 Ga oxygenation event. The result shows that a prominent increase in Hg/TOC is clearly recognized in the shales that stratigraphically just underly the layers recording the oxygenation event, suggesting a close causal link between LIP emplacement and the oxygenation event. Accompanied with this Hg/TOC ratio peak, increased nutrient contents (especially P), pyrite and TOC abundances are also observed. Based on these observations, we proposed a model that the Xiamaling oxygenation event was the result of the LIP's emplacement at ∼1.4–1.35 Ga, which increased nutrient and sulfate supply from continental weathering to the ocean, sustaining elevated primary productivity, organic carbon and pyrite burial. Key Points: High Hg/TOC ratios associated with large igneous province (LIP) emplacement were detected in the ∼1.4 Ga Xiamaling Formation shales of North ChinaHigh P content accompanied with this interval indicates enhanced phosphorous input from LIP weathering to the oceanA causal link between the LIP weathering and oxygenation event at ∼1.4 Ga was suggested [ABSTRACT FROM AUTHOR]

Phosphorous (P) removal in wastewater treatment is essential to prevent eutrophication in water bodies. Side‐stream enhanced biological phosphorous removal (S2EBPR) is utilized to improve biological P removal by recirculating internal streams within a side‐stream reactor to generate biodegradable carbon (C) for polyphosphate accumulating organisms (PAOs). In this study, a full‐scale S2EBPR system in a water resource recovery facility (WRRF) was evaluated for 5 months. Batch experiments revealed a strong positive correlation (r = 0.91) between temperature and C consumption rate (3.56–8.18 mg‐COD/g‐VSS/h) in the system, with temperature ranging from 14°C to 18°C. The anaerobic P‐release to COD‐uptake ratio decreased from 0.93 to 0.25 mg‐P/mg‐COD as the temperature increased, suggesting competition between PAOs and other C‐consumers, such as heterotrophic microorganisms, to uptake bioavailable C. Microbial community analysis did not show a strong relationship between abundance and activity of PAO in the tested WRRF. An assessment of the economic feasibility was performed to compare the costs and benefits of a full scale WRRF with and without implementation of the S2EBPR technology. The results showed the higher capital costs required for S2EBPR were estimated to be compensated after 5 and 11 years of operation, respectively, compared to chemical precipitation and conventional EBPR. The results from this study can assist in the decision‐making process for upgrading a conventional EBPR or chemical P removal process to S2EBPR. Practitioner Points: Implementation of S2EBPR presents adaptable configurations, exhibiting advantages over conventional setups in addressing prevalent challenges associated with phosphorous removal.A full‐scale S2EBPR WRRF was monitored over 5 months, and activity tests were used to measure the kinetic parameters.The seasonal changes impact the kinetic parameters of PAOs in the S2EBPR process, with elevated temperatures raising the carbon demand.PAOs abundance showed no strong correlation with their activity in the full‐scale S2EBPR process in the tested WRRF.Feasibility assessment shows that the benefits from S2EBPR operation can offset upgrading costs from conventional BPR or chemical precipitation. [ABSTRACT FROM AUTHOR]

Agricultural sustainability and land degradation can be monitored through studying soil nutrient dynamics. This study was conducted to investigate the balance and stocks of nitrogen (N) and phosphorus (P) under major land use types and land management (LM) practices in three contrasting agroecological environments in Ethiopia. We employed a nutrient monitoring approach and assessed soil N and P inputs and outputs at watershed and plot scales. Field data were collected from 72 sites representative of the major land uses of the three watersheds for the watershed scale analysis. In addition to the watershed data, 16 experimental runoff plots were established and the response of nutrient balances to improved LM practices for the major land uses, including cropland with three treatments (control, farmyard manure [FYM] and soil bund), grazing land with three treatments (control, exclosure and FYM + exclosure) and bushland with two treatments (control and exclosure). Nutrient balances, flows and stocks varied significantly among agroecological settings, land-use types and LM practices. Severe and negative N balances were found in all agroecological environments, with midland (-70.8) > highland (-61.7) > lowland (-50.3 kg ha-1 yr-1), whereas slightly positive P balances were found in all agro-ecosystems. As a result, the midland (4.2% yr-1) and highland (2.1% yr-1) sites had greater N depletion rates than the lowland site (1.0% yr-1). Our results also demonstrated that applied LM practices improved N balances: by 32%-40% in cropland through FYM and mineral fertilizer, by 7%-18% in grazing land via FYM and exclosure, and by 6%-36% in degraded bushland via exclosure, implying that, implementing FYM and mineral fertilizer for cropland and implementing FYM with exclosure on non-croplands can reverse nutrient depletion in the study sites and in other areas having similar agroecological conditions. [ABSTRACT FROM AUTHOR]

The phosphorous‐based flame retardant additives poly(m‐phenylene methylphosphonate) (PMP) and resorcinol bis(diphenyl phosphate) (RDP) are reacted with bisphenol F and aniline–based benzoxazine (BF‐a). DSC, rheological analysis, FT‐IR, and soxhlet extraction reveal the covalent incorporation of both FR additives—initiating phenols in PMP structure as well as free phenols generated via transesterification reaction in the case of RDP. In contrast to PMP, RDP elongates the processing window but decreases the thermo–mechanical properties. Both additives increase the resistance in reactions against small flames with solely a phosphorous loading of 0.3 wt%, resulting in a V‐0 rating and an improvement in the OI value by up to 2% for RDP and 4% for PMP. Both FRs reduce the heat release rate but increase the smoke production and the smoke toxicity in the case of RDP. [ABSTRACT FROM AUTHOR]

Phosphorous actively participates in numerous metabolic and regulatory activities of almost all living organisms including animals and humans. Therefore, it is considered as an essential macronutrient required supporting their proper growth. On contrary, phytic acid (PA), an antinutritional substance, is widely known for its strong affinity to chelate essential mineral ions including PO43−, Ca2+, Fe2+, Mg2+, and Zn2+. Being one the major reservoir of PO43− ions, PA has great potential to bind PO43− ions in diverse range of foods. Once combined with P, PA transforms into an undigested and insoluble complex namely phytate. Produced phytate leads to a notable reduction in the bioavailability of P due to negligible activity of phytases in monogastric animals and humans. This highlights the importance and consequent need of enhancement of phytase level in these life forms. Interestingly, phytases, catalyzing the breakdown of phytate complex and recycling the phosphate into ecosystem to its available form, have naturally been reported in a variety of plants and microorganisms over past few decades. In pursuit of a reliable solution, the focus of this review is to explore the keynote potential of bacterial phytases for sustainable management of phosphorous via efficient utilization of soil phytate. The core of the review covers detailed discussion on bacterial phytases along with their widely reported applications viz. biofertilizers, phosphorus acquisition, and plant growth promotion. Moreover, meticulous description on fermentation‐based strategies and future trends on bacterial phytases have also been included. [ABSTRACT FROM AUTHOR]

1,3,2‐diazaphospholene hydrides (DAP−H) enable smooth conjugate reduction of polarized double bonds. The transiently formed phosphorus‐enolate provides a potential platform for reductive α‐functionalizations. In this respect, asymmetric C‐heteroatom bond forming processes are synthetically appealing but remain elusive. We report a 1,3,2‐diazaphospholene‐catalyzed three‐step cascade reaction of N‐sulfinyl acrylamides comprised of conjugate reduction, [2,3]‐sigmatropic aza‐Mislow‐Evans rearrangement and subsequent S−O bond cleavage. The obtained enantio‐enriched α‐hydroxy amides are formed in good yields and excellent enantiospecificity. The stereo‐defined P‐bound N,O‐ketene aminal ensures an excellent transfer of chirality from the sulfur stereocenter to α‐carbon. The transformation operates under mild conditions at ambient temperature. Moreover, DAP−H is a competent reductant for the cleavage of formed sulfenate ester, eliminating the extra step in traditional Mislow‐Evans processes. [ABSTRACT FROM AUTHOR]

Given the comparatively lower rotational barriers, the catalytic asymmetric construction of axially chiral biaryl structures, especially those containing a five‐membered heterocycle, still remains a challenge. Herein, we described a general and modular protocol to access atropisomeric arylpyrazole scaffolds containing a phosphorus unit by a dipeptide phosphonium salt catalyzed reaction involving an oxidative central‐to‐axial chirality conversion. This reaction features excellent yields and enantioselectivities, broad substrate scope, and a low catalyst loading, delivering axially chiral phosphine compounds. [ABSTRACT FROM AUTHOR]

Permafrost thaw in peatlands risks emitting vast stores of soil organic carbon (SOC) as greenhouse gases to the atmosphere, yet anoxic conditions and low peat quality may prevent rapid SOC loss. To assess differences in anaerobic SOC mineralization following thaw and vulnerability of previously‐frozen peat, we incubated peat (5° and 14°C) from 15 depths of ⁓6 m cores from different thaw sites including an intact permafrost peat plateau and thermokarst bogs that thawed ∼30 and ∼200 years ago. Furthermore, a glucose‐addition experiment after >700 days assessed whether labile C inputs occurring following thermokarst could accelerate SOC mineralization (priming). We found a common pattern of SOC mineralization rate decreasing with depth and peat age. However, we found no differences in peat mineralization rates among sites for samples of similar age and of corresponding peatland developmental stage. Priming effects were minor and short‐term, and did not vary among sites or with peat developmental stage. We also found mineralization rates from anoxic incubations more than an order of magnitude higher than rates implied from field observations, suggesting mineralization rates from anaerobic incubations should be used mainly to interpret relative differences. Peat humification and peat nitrogen and phosphorous content explained more than 85% of the variability in mineralization rates. Peat quality did not influence the temperature sensitivity of peat mineralization. Overall, the absence of substantial priming effects and the lack of differences in mineralization rates between permafrost peat and peat thawed 200 years ago suggests that rapid peatland SOC loss following thaw is unlikely. Plain Language Summary: Permafrost stores vast amounts of organic matter in peatlands. Ongoing permafrost thaw is exposing previously‐frozen peat to decomposition potentially releasing it as greenhouse gases but the magnitude of this release is uncertain. Following thaw, permafrost peatlands may turn into thermokarst bogs where soils are anoxic and waterlogged, which modifies vegetation. This vegetation and associated roots add easily decomposable substrates (labile) to deep soil layers, which could further increase peat decomposition. We did a two‐year incubation experiment to measure rates of peat decomposition from 15 depths of ⁓6 m cores from a permafrost peatland and thermokarst bogs that thawed 200 years ago. We also added glucose to assess the potential role of labile plant inputs on peat decomposition. We found that peat decomposition decreased with depth and peat age and this was reflected by the peat composition. However, when comparing samples of similar age, we did not find differences in decomposition rates between the permafrost peatland and the thermokarst bogs. The addition of glucose did not substantially stimulate decomposition either with no differences among sites. Overall, our results suggest limited loss of organic matter from previously‐frozen peat following thaw. Key Points: Similar peat decay rates in a thermokarst peatland than in a permafrost peatland suggests rapid organic matter loss after thaw is unlikelyOrganic matter humification indices combined with nutrient content explained more than 85% of the variability in peat decay ratesGlucose addition did not result in sustained priming of permafrost peat and incubation‐based data overestimated in situ mineralization rates [ABSTRACT FROM AUTHOR]

Matrix metalloproteinases (MMPs) attracted medicinal chemists as they are biological targets that are involved in various pathophysiological processes such as extracellular matrix protein degradation, cell‐surface receptor release and cleavage, tumor growth, homeostatic control, and innate immunity. New heterocycles, bearing both silicon and phosphorus in their molecular structures, were successfully produced via reacting silylated isocyanates and/or isothiocyanates with appropriate phosphorus ylides. Reacting nucleophilic phosphacumulenes (2,6) with isocyanate 1 and isothiocyanate 9 yielded four‐membered ring heterocycles containing phosphorus and silicon (4 and 11) and six‐membered rings heterocycles (5, 8 and 12). Moreover, novel heterocycles containing two phosphorus atoms and one silicon atom were produced by the reaction of diphosphorane 13 with 1 or 9. On the other side, four‐membered (23, 26 and 29a) and six‐membered heterocyclic derivatives (20b and 29b) containing two phosphorus atoms in their structures were also obtained from the reaction of phosphallene ylide 13 and substrates (18, 21, 24 and 27). All the final compounds were tested for their MMP‐2 inhibitor activity showing IC50 values in the range of 0.0408–0.4985 μM. The thiolactam derivative 11 and the azaphosphetidin‐4‐one derivative 15, both bearing silicon and phosphorous, showed the highest activity with IC50 values of 0.0408 and 0.0693 μM, respectively, both are significantly higher than that of quercetin (IC50 = 0.1631 μM). Docking simulations were carried out for the most two active compounds 11 and 15 in the vicinity of the active site of MMP‐2 enzyme and both formed coordinate bonds with the zinc cation key interaction for MMP‐2 enzyme. In conclusion, compounds 11 and 15 can be considered as potential MMP‐2 inhibitors and can be subjected to further studies as antimetastatic agents. [ABSTRACT FROM AUTHOR]

Competition for limited resources is a major force in structuring ecological communities. Species minimum resource requirements (R*s) can predict competitive outcomes and evolve under selection in simple communities under controlled conditions. However, whether R*s predict competitive outcomes or demonstrate adaptive evolution in naturally complex communities is unknown. We subjected natural phytoplankton communities to three types of resource limitation (nitrogen, phosphorus, light) in outdoor mesocosms over 10 weeks. We examined the community composition weekly and isolated 21 phytoplankton strains from seven species to quantify responses to the selection of R* for these resources. We investigated the evolutionary change in R*s in the dominant species, Desmodesmus armatus. R*s were good predictors of species changes in relative abundance, though this was largely driven by the success of D. armatus across several treatments. This species also demonstrated an evolutionary change in R*s under resource limitation, supporting the potential for adaptive trait change to modify competitive outcomes in natural communities. [ABSTRACT FROM AUTHOR]

In this work, two monomeric magnesium alkyl complexes (1 and 2) were prepared using bis(phosphino)carbazole framework and among them 1 has been used as a catalyst for hydroboration of alkenes and alkynes with pinacolborane (HBpin). A broad variety of aromatic and aliphatic alkenes and alkynes were efficiently reduced. Anti‐Markovnikov regioselective hydroboration of alkenes and alkynes was achieved, which was confirmed by deuterium‐labelling experiments. The work represents the first example of the use of magnesium in homogeneous catalytic hydroboration of alkene with broad substrate scope. Experimental mechanistic investigations and DFT calculations provided insights into the reaction mechanism. Finally, the hydroboration protocol was extended to terpenes. [ABSTRACT FROM AUTHOR]

The watershed of a large tropical coastal lagoon, historically hosting large sugarcane crops, which has been reduced during the last decades. It suggests that land use and land cover changes (LULCC) would lower the trophic state of the coastal lagoon due to less fertilization application and consequently reducing nutrient transfer into the lagoon. In this context, this study assessed the influence of LULCC, represented by the reduction of the sugarcane crops on the trophic state of a large tropical coastal lagoon. This influence was assessed by means of information about the long‐term overall mass‐balance budget, involving the estimation of the N and P loads from the sugarcane crops, other anthropogenic sources and natural processes; measurements of the river N and P fluxes into the lagoon; its seaward outflow and the long‐term lacustrine nutrient retention. The results indicate that sugarcane crop reduction represented a decrease of 686 t of N and 51 t of P being emitted to the lagoon watershed. However, N and P loads from sugarcane crops were partially replaced by other anthropogenic activities, but even with the reduction of the nutrient fluxes, the long‐term supereutrophic responses of the coastal lagoon was maintained. The sediment‐related C/N and isotopic composition of the lagoon was sensitive to LULCC, indicating changes on the organic matter inputs into the lagoon. The trophic state was also influenced by the soil N and P accumulation and the long‐term nutrient retention within the lagoon imposed by its restricted water connection to the sea. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of carbon dioxide (CO2) into chemicals and fuels has recently attracted much interest, but normally suffers from a high overpotential and low selectivity. In this work, single P atoms were introduced into a N‐doped carbon supported single Fe atom catalyst (Fe‐SAC/NPC) mainly in the form of P−C bonds for CO2 electroreduction to CO in an aqueous solution. This catalyst exhibited a CO Faradaic efficiency of ≈97 % at a low overpotential of 320 mV, and a Tafel slope of only 59 mV dec−1, comparable to state‐of‐the‐art gold catalysts. Experimental analysis combined with DFT calculations suggested that single P atom in high coordination shells (n≥3), in particular the third coordination shell of Fe center enhanced the electronic localization of Fe, which improved the stabilization of the key *COOH intermediate on Fe, leading to superior CO2 electrochemical reduction performance at low overpotentials. [ABSTRACT FROM AUTHOR]

Biogeochemical cycling has often been characterized by physical and microbial processes, yet animals can be essential mediators of energy and nutrients in ecosystems. Excretion by aggregated animals can be an important local source of inorganic nutrients in green food webs; however, whether animals are a source of dissolved energy that can support brown food webs is understudied.We tested whether animal aggregations are a substantial flux of bioavailable dissolved organic matter (DOM) by studying spatially stable, biogeochemical hotspots formed by filter‐feeding freshwater mussels. We used parallel‐factor analysis to quantify DOM fluorescent components composition of mussel excretion and expected digestive breakdown of particulate food sources would lead to excretion of labile DOM. Next, we combined measured excretion rates of DOM, ammonium (NH4+, N) and phosphorous (SRP; P) for 22 species with biomass estimates for 14 aggregations to quantify contributions of DOM, N and P to local availability. Because mussels occupy distinct stoichiometric niches, we anticipated that differences in species biomass and assemblage structure would elicit different flux and stoichiometries of aggregate excretion.Aggregate dissolved organic carbon (DOC) excretion was minor (1%–11%) compared to N (12%–2,860%) and P (1%–97%), yet generalities across assemblages emerged regarding organic matter transformation by mussels towards labile protein‐like compounds compared to abundant aromatic, humic compounds in ambient water.Aggregate excretion of labile DOM was a substantial pool of bioavailable energy, contributing 2%–114% of local labile DOM. Spatial differences in assemblage structure led to strong differences in aggregate flux and stoichiometry driven by biomass and stoichiometric trait expression of species with contrasting dominance patterns.Under the nutrient conditions of our study (high C:nutrient), biogeochemical hotspots associated with low‐trophic position animal biomass may indirectly control energy flow to the brown food web by shifting C:nutrient stoichiometry available to microbes or directly by increasing the flux of microbially available DOM. Collectively, our results highlight a potentially substantial flux of labile energy and nutrients to microbial communities through the transformation of ingested organic matter by aggregations of animals and emphasize that shared functional trait classification may not translate into shared ecological function. A free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

Gallaphosphene L(Cl)GaPGaL (2; L=HC[C(Me)N(2,6‐i‐Pr2C6H3)]2), which is synthesized by reaction of LGa(Cl)PCO (1) with LGa, reacts with [Na(OCP)(dioxane)2.5] to LGa(OCP)PGaL (3), whereas chloride abstraction with LiBArF4 yields [LGaPGaL][BArF4] (4; BArF4=B(C6F5)4). 4 represents a heteronuclear analog of the allyl cation according to quantum chemical calculations. Remarkably, 2 reversibly reacts with CO2 to yield L(Cl)Ga−P[μ‐C(O)O]2GaL (5), while reactions with acetophenone and acetone selectively give compounds 6 and 7 by C(sp3)−H bond activation. [ABSTRACT FROM AUTHOR]

Pyrene appended free‐base, phosphorus(V) and gallium (III) corrole conjugates were synthesized and characterized. Efficient β‐β′ dimerization of corroles was achieved by oxidation with p‐chloranil in moderate yield from their respective metallated corroles. The weak ground state electronic coupling between pyrene and corrole units was established by photophysical and electrochemical investigations. The fluorescence spectral studies showed a red shifted emission maximum for dimer with respect to their monomeric counterpart due to possible π‐conjugation and supported by the density functional theory (DFT). The electrochemical investigation revealed multiple oxidation associated with the corrole and pyrene centers. [ABSTRACT FROM AUTHOR]

Solid organ transplantation in children and adolescents provides many benefits through improving critical organ function, including better growth, development, cardiovascular status, and quality of life. Unfortunately, bone status may be adversely affected even when overall status is improving, due to issues with pre‐existing bone disease as well as medications and nutritional challenges inherent post‐transplantation. For all children and adolescents, bone status entering adulthood is a critical determinant of bone health through adulthood. The overall health and bone status of transplant recipients benefits from attention to regular physical activity, good nutrition, adequate calcium, phosphorous, magnesium and vitamin D intake and avoidance/minimization of soda, extra sodium, and obesity. Many immunosuppressive agents, especially glucocorticoids, can adversely affect bone function and development. Minimizing exposure to "bone‐toxic" medications is an important part of promoting bone health in children post‐transplantation. Existing guidelines detail how regular monitoring of bone status and biochemical markers can help detect bone abnormalities early and facilitate valuable bone‐directed interventions. Attention to calcium and vitamin D supplementation, as well as tapering and withdrawing glucocorticoids as early as possible after transplant, can provide best bone outcomes for these children. Dual‐energy X‐ray absorptiometry can be useful to detect abnormal bone mass and fracture risk in this population and newer bone assessment methods are being evaluated in children at risk for poor bone outcomes. Newer bone therapies being explored in adults with transplants, particularly bisphosphonates and the RANKL inhibitor denosumab, may offer promise for children with low bone mass post‐transplantation. [ABSTRACT FROM AUTHOR]

BACKGROUND Inorganic phosphate (Pi) is key to improved crop yields; however, agricultural drainage leads to the accumulation of this nutrient in aquatic ecosystems and promotes the formation of harmful algal blooms. The aim of this study was to produce a hydrogel with high binding capacity and affinity towards Pi produced from carboxymethyl cellulose (CMC) and iron (III) chloride (FeCl3). RESULTS: CMC was converted to CMC‐Fe composites by incubation with FeCl3. The half‐lives (t1/2) of CMC functionalization with 25 mmol L−1 FeCl3 were 11.56 min (1.5% CMC) and 13.91 min (3.0% CMC). The apparent dissociation constants (KD App) of CMC‐Fe were estimated to be 33.99 μmol L−1 (1.5% CMCFe) and 24.81 μmol L−1 (3.0% CMC‐Fe). The phosphate binding capacity (PBC) of the hydrated hydrogels were 74.0 ± 3.06 mg g−1 (1.5% CMCFe) and 91.4 ± 4.51 mg g−1 (3.0% CMC‐Fe). Laboratory‐scale continuous flow filtration studies showed an average removal of 91.3% (mixed filter) and 52.5% (unmixed filter). Batch type treatment of agricultural drainage showed a reduction in Pi content from 0.40 to 0.11 mg L−1 (1.5% CMC‐Fe) and 0.17 mg L−1 (3.0% CMC‐Fe). The amount of bound‐Pi was 26.7 ± 0.63 μg g−1 (1.5% CMC‐Fe) and 32.8 ± 1.31 μg g−1 (3.0% CMC‐Fe). The iron leached from 1.5% and 3.0% CMC‐Fe beads was 11.98 ± 1.80 and 3.57 ± 1.63 mg g−1, respectively. CONCLUSION: The CMC‐Fe hydrogel shows great promise as a Pi‐adsorbing material with applications in the treatment of agricultural drainage. © 2020 Society of Chemical Industry (SCI) [ABSTRACT FROM AUTHOR]

The utilization of monomeric, lower phosphorous oxides and oxoanions, such as metaphosphite (PO2−), which is the heavier homologue of the common nitrite anion but previously only observed in the gas phase and by matrix isolation, requires new synthetic strategies. Herein, a series of rhenium(I–III) complexes with PO2− as ligand is reported. Synthetic access was enabled by selective oxygenation of a terminal phosphide complex. Spectroscopic and computational examination revealed slightly stronger σ‐donor and comparable π‐acceptor properties of PO2− compared to homologous NO2−, which is one of the archetypal ligands in coordination chemistry. [ABSTRACT FROM AUTHOR]

Magnetic particles associated with iron (Fe) oxides are widespread on the surface of Earth and Mars and serve as reasonable climatic indicators. Ferrimagnetic maghemite (Mgh) and antiferromagnetic hematite (Hm), which dominate magnetism and redness, often coexist or compete with each other in soils and sediments. The formation efficiency of Mgh relative to Hm could be modulated by geochemical background besides climate, especially by phosphate (P), which has a high affinity for the surfaces of precursor iron oxides in natural systems. We investigated two Ferralsol sequences around a P mining field with similar climates and contrasting P/Fe ratios. High P/Fe ratios retard iron oxide crystallization, grain growth, and transformation into Hm, thereby promoting more effective accumulation of ferrimagnetic Mgh as an intermediate product. The lack of ligand‐protected effects well interprets asynchronous changes in magnetism and redness in soils and sediments across large spatiotemporal scales, especially in highly weathered soils. Plain Language Summary: Iron oxides are critical carriers of magnetism and dyeing agents of soils and sediments. The concentration of pedogenic maghemite (Mgh) and hematite (Hm), which dominate magnetism and redness, is considered to be controlled by the primary iron input and climate conditions. However, phosphate exhibits a high affinity for the surfaces of precursor iron oxides, especially in highly weathered soils. We investigated two Ferralsol sequences around a P mining field with contrasting P/Fe ratios but similar climates. High P/Fe ratios are observed to impede iron oxide crystallization, grain growth, and transformation into Hm, thereby promoting more effective accumulation of ferrimagnetic Mgh as an intermediate product. The presence and absence of ligand‐protected effects help explain asynchronous changes in magnetism and color in nature systems across large spatiotemporal scales. Key Points: Iron oxide crystallinity increases monotonically as soil P/Fe decreasesFerrimagnets accompanying the formation of hematite are enriched with accelerations under high P/Fe but with even rates under low P/FeFerrimagnets grow and transform into hematite more rapidly without the proper level of P ligand protection [ABSTRACT FROM AUTHOR]

Natural and calcined eggshell as adsorbent alternatives were evaluated for the removal of phosphorous from water. Calcined eggshell was obtained after treating the natural eggshell at 900 °C in electric furnace for 2 h. The examination on their characteristics was carried out with thermogravimetry and differential thermal analysis (TG/DTA), scanning electron microscope (SEM), X‐ray diffractometer (XRD), and energy dispersive X‐ray spectrometer (EDX). The working solution containing phosphorous was prepared by dissolving KH2PO4 with distilled water. The batch adsorption experiment was conducted by changing various variables such as initial phosphorous concentration, dosage of natural and calcined eggshell, contact time, and pH. It turned out that natural eggshell was unable to remove phosphorous from water, whereas a considerable amount of phosphorous by calcined eggshell was removed in initial contact time (0.25 h). The removal efficiencies were found to be 99.5 and 99.28% at experimental conditions of 5 mg/g of initial phosphorous concentration and a 1.0 g of calcined eggshell dosage, respectively. The removal efficiencies of phosphorous by calcined eggshell were dependent on the abovementioned variables. The difference in the removal behavior of phosphorous by natural and calcined eggshell may be explained due to the different pH values and Ca2+ concentration in solution. The research results suggested that phosphorous removal mechanism by natural eggshell is caused by adsorption of phosphate (as phosphorous source) onto the surface of natural eggshell, however, on the contrary to this, the phosphorous removal on calcined eggshell is arisen from the binding of phosphosphate and calcium resulting in precipitation of calcium phosphate. Experimental data were applied by the pseudofirst‐order and pseudosecond‐order kinetics models and Freundlich and Langmuir isotherm models, respectively. The pseudosecond‐order kinetics model and Langmuir isotherm model were more suitable for calcined eggshell owing to the higher correlation coefficient R2. In conclusion, the result showed that calcined eggshell could become a favorable adsorbent material for removing phosphorous from water. [ABSTRACT FROM AUTHOR]

The lithium phosphidoaluminate Li9AlP4 represents a promising new compound with a high lithium ion mobility. This triggered the search for new members in the family of lithium phosphidotrielates, and the novel compounds Li3AlP2 and Li3GaP2, obtained directly from the elements via ball milling and subsequent annealing, are reported here. It was unexpectedly found through band structure calculations that Li3AlP2 and Li3GaP2 are direct band gap semiconductors with band gaps of 3.1 and 2.8 eV, respectively. Rietveld analyses reveal that both compounds crystallize isotypically in the orthorhombic space group Cmce (no. 64) with lattice parameters of a=11.5138(2), b=11.7634(2) and c=5.8202(1) Å for Li3AlP2, and a=11.5839(2), b=11.7809(2) and c=5.8129(2) Å for Li3GaP2. The crystal structures feature TrP4 (Tr=Al, Ga) corner‐ and edge‐sharing tetrahedra, forming two‐dimensional ∞2TrP23- layers. The lithium atoms are located between and inside these layers. The crystal structures were confirmed by MAS‐NMR spectroscopy. [ABSTRACT FROM AUTHOR]

The lithium phosphidoaluminate Li9AlP4 represents a promising new compound with a high lithium ion mobility. This triggered the search for new members in the family of lithium phosphidotrielates, and the novel compounds Li3AlP2 and Li3GaP2, obtained directly from the elements via ball milling and subsequent annealing, are reported here. It was unexpectedly found through band structure calculations that Li3AlP2 and Li3GaP2 are direct band gap semiconductors with band gaps of 3.1 and 2.8 eV, respectively. Rietveld analyses reveal that both compounds crystallize isotypically in the orthorhombic space group Cmce (no. 64) with lattice parameters of a=11.5138(2), b=11.7634(2) and c=5.8202(1) Å for Li3AlP2, and a=11.5839(2), b=11.7809(2) and c=5.8129(2) Å for Li3GaP2. The crystal structures feature TrP4 (Tr=Al, Ga) corner‐ and edge‐sharing tetrahedra, forming two‐dimensional ∞2TrP23- layers. The lithium atoms are located between and inside these layers. The crystal structures were confirmed by MAS‐NMR spectroscopy. [ABSTRACT FROM AUTHOR]

Rising temperatures with increased drought pose two challenges for management of future biodiversity. First, are the most vulnerable species concentrated in specific regions and habitats? Second, where can landscape heterogeneity potentially mitigate impacts? We conducted a comprehensive trait analysis of forest plots spanning the eastern United States to quantify how resource‐acquisitive species respond to moisture‐soil‐climate interactions. We found that resource‐acquisitive species, including nutrient‐acquisitive and moisture‐acquisitive species, respond disproportionately to environmental gradients, and their response is largely explained by soil variation. We showed that the strong boundary of resource‐acquisitive species occurs near the last glacial limit, highlighting one of the clearest indicators of soil controls. Although local soil moisture may reduce drought‐induced stress for moisture‐acquisitive species, nutrient‐acquisitive species remain vulnerable on wet soils in dry climates. The results suggest that theories explaining species distributions should devote close attention to the combination of local drainage and soil type. Plain Summary language: Global warming and drought may cause harm to the biodiversity on the planet. But we may be able to protect species if we can identify vulnerable habitats and regions. To address this challenge, we analyzed a large data set of forest plots across the eastern United States. Our study showed that soil type and local soil moisture play important roles in species response to dry and warm conditions. Our results revealed a sharp change in the population of resource‐acquisitive species near the boundary of the last glaciation, indicating a strong soil control. While nutrient‐acquisitive species did not benefit from local moisture availability, moisture‐acquisitive species favored these conditions. Key Points: Nutrient‐acquisitive species tend to locate on the north of the last glacial limitNutrient‐acquisitive species derive limited benefit from local moisture availabilityHeterogeneity in moisture availability may provide drought refuges for moisture‐acquisitive species [ABSTRACT FROM AUTHOR]

In recent years, human urine has been successfully used as an electrolyte and organic substrate in bioelectrochemical systems (BESs) mainly due of its unique properties. Urine contains organic compounds that can be utilised as a fuel for energy recovery in microbial fuel cells (MFCs) and it has high nutrient concentrations including nitrogen and phosphorous that can be concentrated and recovered in microbial electrosynthesis cells and microbial concentration cells. Moreover, human urine has high solution conductivity, which reduces the ohmic losses of these systems, improving BES output. This review describes the most recent advances in BESs utilising urine. Properties of neat human urine used in state‐of‐the‐art MFCs are described from basic to pilot‐scale and real implementation. Utilisation of urine in other bioelectrochemical systems for nutrient recovery is also discussed including proofs of concept to scale up systems. [ABSTRACT FROM AUTHOR]

The article presents a study which assessed the effects of stream water nutrient concentrations on biofilm growth in streams draining mountainous permafrost headwaters in northeast (NE) Greenland. Also cited are the use of nutrient diffusing substrates to analyze autotrophic and total biomass of biofilms, and the influence of stream nitrogen availability on algal biofilm accrual in high-Arctic streams.

There has been a recent upsurge in the study and application of approaches utilizing cyclotriphosphate 1 (cyclo‐TP, also known as trimetaphosphate, TMP) and/or proceeding through its analogues in synthetic chemistry to access modified oligo‐ and polyphosphates. This is especially useful in the area of chemical nucleotide synthesis, but by no means restricted to it. Enabled by new high yielding and easy‐to‐implement methodologies, these approaches promise to open up an area of research that has previously been underappreciated. Additionally, refinements of concepts of prebiotic phosphorylation chemistry have been disclosed that ultimately rely on cyclo‐TP 1 as a precursor, placing it as a potentially central compound in the emergence of life. Given the importance of such concepts for our understanding of prebiotic chemistry in combination with the need to readily access modified polyphosphates for structural and biological studies, this paper will discuss selected recent developments in the field of cyclo‐TP chemistry, briefly touch on ultraphosphate chemistry, and highlight areas in which further developments can be expected. [ABSTRACT FROM AUTHOR]

Key Clinical Message: Hypophosphatemia postintravenous iron is frequent but under‐recognized. If prolonged or recurrent, it can cause osteomalacia. The likely mechanisms are direct toxicity to proximal tubular cells causing phosphate wasting, elevated Fibroblast growth factor‐23 (FGF‐23), and reduced 1,25‐dihydroxyvitamin D (1,25(OH)2D). Hypophosphatemia may be severe and persist for months, necessitating phosphate replacement until normalization of serum levels occurs. [ABSTRACT FROM AUTHOR]

Artificial humic acids (A‐HA) made from biomass in a hydrothermal process turn otherwise highly insoluble phosphates (e.g. iron phosphate as a model) into highly available phosphorus, which contributes to the fertility of soils and the coupled plant growth. A detailed electron microscopy study revealed etching of the primary iron phosphate crystals by the ‐COOH and phenolic groups of humic acids, but also illustrated the importance of the redox properties of humic matter on the nanoscale. The combined effects result in the formation of then bioavailable phosphate nanoparticles stabilized by humic matter. Typical agricultural chemical tests indicate that the content of total P and directly plant‐available P improved largely. Comparative pot planting experiments before and after treatment of phosphates with A‐HA demonstrate significantly enhanced plant growth, as quantified in higher aboveground and belowground plant biomass. [ABSTRACT FROM AUTHOR]

In this paper, a Phosphorous ‐ Aluminium ‐ Nitride synergistic flame retardant (PAN) was synthesized by phosphoric acid, glycerol, aluminium sulfate and urea, though a one‐pot process. The PAN was durably grafted onto the surface of cotton fabric by the simple process of soak‐dry‐cure. At the same time, the synergistic effect of the aluminium element and Phosphorous ‐ Nitrogen flame retardants (PN) was investigated. The flame‐retardant effect is the best when the conttent of alumium is 2.5 mol% (percentage of phosphoricacid) in PAN. The analyses of FTIR and XPS results suggested that PAN was grafted onto the cotton by forming a strong P−O‐C covalent bond on the surface of fiber. The SEM and Whiteness test proved that the flame‐retardant finishing cotton fabric do possess good morphology and whiteness. The thermal stability and flame retardancy of the PAN treated cotton fabric were assessed by TG and vertical flammability test. Then, found the aluminium sulfate in PAN had synergistic effect, and the PAN had significant flame retardancy in application. [ABSTRACT FROM AUTHOR]

Mediterranean oak savannas, such as Spanish dehesas, are multiple resource-limited ecosystems found in semiarid regions which are key contributors to interannual variability of the global carbon (C) budget. Interactions between nitrogen (N) and phosphorus (P) cycles are expected to play a major role in overall ecosystem function as anthropogenic N deposition shifts ecosystems from N to P limitation, leaving unknown how increased N availability might influence C uptake. Therefore, the fate of N additions in dehesas is important for understanding global C cycling. Using a 15N tracer experiment within fertilized (N or N + P) plots of a Holm oak dehesa, we tested the effects of ecosystem spatial heterogeneity (habitat), P addition, and time on the fate of added N.We expected that open pasture areas would retain more of the added N in biological components due to greater N limitation, that the addition of P would enhance N retention in biological components relative to N alone, and that added N would shift from being within the microbial biomass immediately after addition to being predominantly within plants at the beginning of the following growing season. We found that open pasture plots with N only had the greatest label recovery seven months after the start of the experiment, supporting the idea that open pasture was more N-limited than under-canopy areas. However, soil was the largest sink for added N, regardless of habitat, treatment, or time. Our results suggest that abiotic fixation of N may play an important role in modifying the effects of N deposition in dehesas. [ABSTRACT FROM AUTHOR]

The utilization of noble‐metal catalysts for the hydrogen evolution reaction (HER) provides an efficient strategy for hydrogen acquisition. However, exploring catalysts with suitable hydrogen binding strength for the HER process is always of great importance, but extremely challenging. In this work, sulfur and phosphor as electron‐withdrawing elements were incorporated into carbon nanotube (CNT)‐supported Ru catalysts, which were prepared through a facile solution reduction reaction and post thermo treatment. Owing to the suitable electronegativity provided by P and synergistic effects of the carbon nanotubes, the RuP2/CNT achieved a high catalytic performance as a HER electrocatalyst. This may result from the modulation effect of the electronic properties and the depressed adsorption free energy of RuP2. Electrochemical tests present that the RuP2/CNT composite exhibit a small overpotential of 58 mV at 10 mA cm−2 in acidic electrolyte. In a neutral or alkaline environment, the overpotential is 82 and 40 mV, respectively. The RuP2/CNT electrode also possesses stable durability for long‐time cycling, suggesting its remarkable property as promising all‐pH HER catalyst. [ABSTRACT FROM AUTHOR]

Agricultural runoff from the Mississippi‐Atchafalaya River Basin delivers nitrogen (N) and phosphorus (P) to the Gulf of Mexico, causing hypoxia, and climate drives interannual variation in nutrient loads. Climate phenomena such as El Niño–Southern Oscillation may influence nutrient export through effects on river flow, nutrient uptake, or biogeochemical transformation, but landscape variation at smaller spatial scales can mask climate signals in load or discharge time series within large river networks. We used multivariate autoregressive state‐space modeling to investigate climate signals in the long‐term record (1979–2014) of discharge, N, P, and SiO2 loads at three nested spatial scales within the Mississippi‐Atchafalaya River Basin. We detected significant signals of El Niño–Southern Oscillation and land‐surface temperature anomalies in N loads but not discharge, SiO2, or P, suggesting that large‐scale climate phenomena contribute to interannual variation in nutrient loads through biogeochemical mechanisms beyond simple discharge‐load relationships. Plain Language Summary: Runoff of excess nutrients from crop fertilizers applied throughout the Mississippi‐Atchafalaya River Basin, particularly nitrogen (N) and phosphorus (P), pollute freshwater and coastal ecosystems such as the Gulf of Mexico. Though agriculture is the main source, year‐to‐year variation in the size of nutrient loads is largely controlled by precipitation and river flow, which mobilize nutrients from the landscape. Additional climate variables, such as temperature, influence nutrient loads by controlling rates of nutrient uptake or transformation by plants, algae, and microbes, but these processes may be difficult to detect in a nearly continental‐scale river network with heterogeneous subbasins. We identified signals of multiple large‐scale climate phenomena in the long‐term record (1979–2014) of nutrient loads from the Mississippi River and its major tributaries. Climate effects on nutrient loads, particularly N, were different and often stronger than on river flow, indicating that long‐term patterns in nutrient loads were influenced by processes beyond simple precipitation‐driven runoff. Variable effects of climate on nutrient export present challenges for reducing nutrient loads to the Mississippi River and Gulf of Mexico. Adjustments to targeted reductions may be needed as global and regional climates change. Key Points: Significant signals of large‐scale climate phenomena appear in N loads but not discharge, SiO2, or P loads in the Mississippi River Basin at multiple spatial scalesEffects of climate variables differ among nutrients (N, P, SiO2) and nutrient forms (nitrate, ammonium)Climate‐driven processes independent of river flow contribute to temporal variation in nutrient loads within the Mississippi River Basin [ABSTRACT FROM AUTHOR]

High temperature has become a bottleneck limiting rice production in many rice‐growing districts. Silicon is considered as a beneficial element for rice development, being involved in mitigating adversity stress. In order to ascertain how high temperature and silicon affect nitrogen (N), phosphorous (P) and potassium (K) translocation efficiencies and allocation in rice plants, a field experiment with split plot design was conducted in two consecutive years. Silicon fertilizer treatments, including applying silicon fertilizer and without applying silicon fertilizer, were regarded as main plots. Temperature treatments, including high daytime temperature (HDT) and normal temperature (NT), were assigned as subplots. The results indicated that, as compared to NT, HDT reduced the translocation efficiencies of N, P and K in leaves and stems plus sheaths except for the K translocation efficiency in stems plus sheaths. Moreover, HDT decreased grain yield and the allocation rates of N, P and K in panicles at maturity. Under HDT, the application of silicon fertilizer obviously enhanced the N translocation efficiency of leaves and stems plus sheaths, and the K translocation efficiency of leaves. The application of silicon fertilizer increased grain yield and the allocation rates of N and K in panicles at maturity under HDT. Correlation analysis showed that rice grain yield was positively significantly correlated with N, P and K translocation efficiencies of leaves and their allocation rates in panicles at maturity. Conversely, grain yield was negatively related to the N and P allocation rates in leaves and stems plus sheaths at maturity. These results imply that HDT generated adverse effect on the translocation efficiency of nutrition in rice plants, which might be another damage induced by high temperature to the formation of rice grain yield. Additionally, silicon fertilizer could play a key role in positively regulating the N and K translocation efficiencies and allocation rates in rice under HDT. [ABSTRACT FROM AUTHOR]

The synergy effects of phosphorus modifier on highly ordered mesoporous binary metal oxides of Co3O4−Al2O3 (m‐CoAl), prepared by nanocasting method using a hard template of KIT‐6, were observed by an enhanced catalytic and structural stability of the m‐CoAl during CO hydrogenation to hydrocarbons. The enhanced structural stability of the ordered mesoporous structures on the phosphorous‐modified m‐CoAl at an optimal amount of phosphorous modifier below 0.3 wt%P (P(3)/m‐CoAl) was attributed to the partial formation of thermally stable metal phosphates under a reductive Fischer‐Tropsch synthesis (FTS) reaction condition. The positive effects of the phosphorous modifier were originated from the partially formed SiO2‐like AlPO4 phases on the outer surfaces of the m‐CoAl, as well as from partially formed irreducible and thermally stable spinel‐type cobalt aluminates (CoAl2O4). The hydrophobic SiO2‐like tridymite AlPO4 surfaces on the ordered matrices of the P/m‐CoAl also effectively prevented the heavy wax (or coke precursors) depositions. The structural instability of the P/m‐CoAl was observed at a higher phosphorous content above 0.5wt%P by preferentially forming the largely segregated mixed metal oxides such as Co3O4−CoAl2O4−Co3(PO4)2 through the phase transformations of the surface excess AlPO4. Phosphorus modifier on an ordered mesoporous Co3O4−Al2O3 binary metal oxides revealed an enhanced catalytic activity and structural stability even under a reductive Fischer‐Tropsch synthesis (FTS) reaction condition due to the partially formed SiO2‐like hydrophobic AlPO4 as well as cobalt aluminate (CoAl2O4) phases with a less deposition of coke precursors. [ABSTRACT FROM AUTHOR]

Aquatic macrophytes modify the sediment biogeochemistry via radial oxygen loss (ROL) from their roots. However, the variation in ROL and its implication for nutrient availability remains poorly explored.Here, we use planar O2 optodes to investigate the spatial heterogeneity of oxic niches within the rhizosphere of Vallisneria spiralis and their alteration following variable light and ambient O2 levels. The effect of ROL on NH4+ and PO43− distribution in the rhizosphere was evaluated by a combination of 15N isotopic techniques, 2D sampling, and electron microscopy.A single specimen of V. spiralis could maintain an oxidised sediment volume of 41–47 cm3 and 10–27 cm3 in the rhizosphere at 100% and 38% dissolved oxygen saturation in the overlying water, respectively. Whatever the environmental conditions, the ROL was, however, very heterogeneous and dependent on root age and architecture of the root system.ROL stimulated the coupling between denitrification and nitrification in the sediment both under dark (+25 μmol N‐N2 m−2 hr−1) and light (+70 μmol N‐N2 m−2 hr−1) conditions. This, in combination with plant uptake, contributed to intense removal of NH4+ from the pore water. Similarly, PO43− was highly depleted in the rhizosphere. The detection of Fe‐P plaques on the roots surface indicated substantial entrapment of P as a consequence of ROL.The extensive spatio‐temporal heterogeneity of oxic and anoxic conditions ensured that aerobic and anaerobic processes co‐occurred in the rhizosphere and this presumably reduced potential nutrient limitation while maximising plant fitness in an otherwise hostile reduced environment. [ABSTRACT FROM AUTHOR]

The porous microspherical Nitrogen and Phosphorus‐co‐doped NiFe2O4/Single‐Walled Carbon Nanotubes (NP‐NiFe2O4/SWNTs) had been fabricated. Nitrogen (N) and phosphorous (P) were co‐doped to increase the active sites. And SWNTs hybrid was to obtain the enhanced conductivity, large specific surface area and more active sites. The hierarchical, porous structure and highly conductive SWNTs enables efficient transport of the electrons generated during oxygen evolution reaction (OER). Thus, NP‐NiFe2O4/SWNTs was demonstrated as a high‐performance catalyst for OER with a small overpotential of 247 mV at 10 mA cm−2 and low Tafel slope of 83.6 mV dec−1. The outstanding performance of NP‐NiFe2O4/SWNTs can also made it serve as anode for water splitting at a cell voltage of 1.595 V, which surpasses the precious RuO2 and Pt/C. That's dope! Porous microspherical nitrogen and phosphorus‐co‐doped NiFe2O4/single‐walled carbon nanotubes have been developed for efficient oxygen evolution reaction, which showed the strategy to improve the catalytic activity by designing and tuning the hierarchical structure, composition, conductivity and active sites. [ABSTRACT FROM AUTHOR]

The environmental variability at local scale results in different physiognomic types of mangrove forest. However, this variability has never been considered in studies of mangrove genetic variability. This study analyzed the genetic and morphological variability and structure of Rhizophora mangle at regional and local scales in the Yucatan Peninsula. Thirteen mangrove populations (eight scrub and five tall), located in seven sites, were sampled, and their morphological variability and relationship with the availability of phosphorus and salinity were analyzed. The diversity and genetic structure were estimated at different hierarchical levels with nine microsatellites, also Bayesian inference and Principal Coordinates Analysis were used. We found a great morphological variability of R. mangle that responded to local environmental variability and not to the precipitation gradient of the peninsula. The genetic diversity found in the peninsula was greater than that reported for other populations in Mexico and was grouped into two regions: the Gulf of Mexico and the Caribbean Sea. At a local scale, tall and scrub mangroves had significant genetic differentiation suggesting that ecological barriers promote genetic differentiation within sites. These results need to be considered in future population genetic studies and for mangrove management and conservation. Mangrove species Rhizophora mangle has many physiognomic forms, the short one or scrub type occupies large extensions. We evaluate whether this type is genetically different from the tall type and found that differences are greater at local scale than at regional scale, indicating that short‐distance ecological barriers exist between these two types of mangrove within a site. [ABSTRACT FROM AUTHOR]

The hydrolysis of cellulose and hemicelluloses in the presence of solid acid catalysts is of great importance as an entry process for the production of biofuels and chemicals. In this work, the effect of carbon surface chemistry on the catalyst conversion and selectivity in hydrolysis of cellobiose to glucose was studied. Solid catalysts based on carbon xerogels (CXs) containing various functionalities incorporating heteroatoms (S, P, N, O), as confirmed by XPS, TPD, ICP and EA analyses, were successfully prepared. CXs containing 3.4 wt % of phosphorus showed the best catalytic performance, reaching 90 % conversion of cellobiose with 72 % selectivity to glucose, under oxidative atmosphere and in a short reaction time of only 4 h. The presence of phosphonates (−P−C−) was found to increase the selectivity to glucose up to unprecedented 87 %. On the contrary, carbonyls, quinones, pyrydinic, pyrrolic and sulfonic groups were found to promote glucose degradation, leading to a final low yield of this product. Additionally, the increased concentration of oxygen in the reaction atmosphere was shown to significantly weaken the β (1–4)‐glycosidic bond, increasing the final yield of glucose. Fancy black scissors for cutting green waste: The effect of surface chemistry of carbon xerogels doped with various heteroatoms on the breaking of β (1–4) glycosidic bond in cellobiose was evaluated. Carbon functionalized with phosphorus reached impressive selectivity to glucose of 87 % in just 4 h. [ABSTRACT FROM AUTHOR]

Abstract: Stoichiometric differences among organisms can affect trophic interactions and rates of nutrient cycling within ecosystems. However, we still know little about either the underlying causes of these stoichiometric differences or the consistency of these differences across large geographical extents. Here, we analyse elemental (carbon, nitrogen, phosphorus) composition of 872 aquatic macroinvertebrates (71 species) inhabiting tank bromeliads (n = 140) from five distantly located sites across Central and South America to (i) test phylogenetic, trophic and body size scaling explanations for why organisms differ in elemental composition and (ii) determine whether patterns in elemental composition are universal or context dependent. Taxonomy explained most variance in elemental composition, even though phylogenetic signals were weak and limited to regional spatial extents and to the family level. The highest elemental contents and lowest carbon:nutrient ratios were found in organisms at high trophic levels and with smaller body size, regardless of geographical location. Carnivores may have higher nutrient content and lower carbon:nutrient ratios than their prey, as organisms optimize growth by choosing the most nutrient‐rich resources to consume and then preferentially retain nutrients over carbon in their bodies. Smaller organisms grow proportionally faster than large organisms and so are predicted to have higher nutrient requirements to fuel RNA and protein synthesis. Geography influenced the magnitude, more than the direction, of the ecological and/or phylogenetic effects on elemental composition. Overall, our results show that both ecological (i.e. trophic group) and evolutionary drivers explain among‐taxa variation in the elemental content of invertebrates, whereas intraspecific variation is mainly a function of body size. Our findings also demonstrate that restricting analyses of macroinvertebrate stoichiometry solely to either the local scale or species level affects inferences of the patterns in invertebrate elemental content and their underlying mechanisms. A plain language summary is available for this article. [ABSTRACT FROM AUTHOR]