To meet the growing food demand while addressing the multiple challenges of exacerbating phosphorus (P) pollution and depleting P rock reserves1-15, P use efficiency (PUE, the ratio of productive P ...output to P input in a defined system) in crop production needs to be improved. Although many efforts have been devoted to improving nutrient management practices on farms, few studies have examined the historical trajectories of PUE and their socioeconomic and agronomic drivers on a national scale1'2'6'7,11'16'17. Here we present a database of the P budget (the input and output ofthe crop production system) and PUE by country and by crop type for 1961-2019, and examine the substantial contribution of several drivers for PUE, such as economic development stages and crop portfolios. To address the P management challenges' we found that global PUE in crop production must increase to 68-81%, and recent trends indicate some meaningful progress towards this goal. However, P management challenges and opportunities in croplands vary widely among countries.
Nutrients, such as nitrogen and phosphorus, provide vital support for human life, but overloading nutrients to the Earth system leads to environmental concerns, such as water and air pollution on ...local scales and climate change on the global scale. With an urgent need to feed the world's growing population and the growing concern over nutrient pollution and climate change, sustainable nutrient management has become a major challenge for this century. To address this challenge, the growing body of research on nutrient budgets, namely the nutrient inputs and outputs of a given system, has provided great opportunities for improving scientific knowledge of the complex nutrient cycles in the coupled human and natural systems. This knowledge can help inform stakeholders, such as farmers, consumers, and policy makers, on their decisions related to nutrient management. This paper systematically reviews major challenges, as well as opportunities, in defining, quantifying, and applying nutrient budgets. Nutrient budgets have been defined for various systems with different research or application purposes, but the lack of consistency in the system definition and its budget terms has hindered intercomparison among studies and experience‐sharing among researchers and regions. Our review synthesizes existing nutrient budgets under a framework with five systems (i.e., Soil‐Plant system, Animal system, Animal‐Plant‐Soil system, Agro‐Food system, and Landscape system) and four spatial scales (i.e., Plot and Farm, Watershed, National, and Global scales). We define these systems and identify issues of nitrogen and phosphorus budgets within each. Few nutrient budgets have been well balanced at any scale, due to the large uncertainties in the quantification of several major budget terms. The type and level of challenges vary across spatial scales and also differ among nutrients. Improvement in nutrient budgets will rely not only on the technological advancement of scientific observations and models but also on better bookkeeping of human activity data. While some nutrient budget terms may need decades, or even centuries, of research to be well quantified within desirable levels of uncertainties, it is imperative to effectively communicate to interested stakeholders our understanding of nutrient budgets so that scientists and a variety of stakeholders can work together to address the sustainable nutrient management challenge of this century.
Plain Language Summary
Managing nutrients, such as nitrogen and phosphorus, is fundamental, yet challenging, for sustainable development. Nutrients are critical for plant and animal growth in agriculture and in nonagricultural ecosystems and are consequently important for food security and climate stability, as well as human health. However, historical and ongoing increases in nutrient inputs to agriculture, while increasing food production, have also contributed to severe environmental problems, ranging from local water and air pollution to global climate change. Quantifying the nutrient inputs and outputs of a farm, watershed, or any other well‐defined boundary advances our knowledge of how to maintain a nutrient balance, which is an essential step toward sustainable nutrient management. So far, many research efforts have been devoted to quantifying nutrient budgets and to improving nutrient management for different systems (e.g., farms and food supply chains) and at different spatial scales (e.g., from a single farm to the entire world). However, due to the complex nature of nutrient cycles and incomplete data sets, challenges remain in quantifying and understanding nutrient budgets to inform policies and actions for sustainable nutrient management. With a systematic review of major challenges in defining, quantifying, and applying nutrient budgets, this paper calls for collective efforts by researchers, farmers, watershed managers, consumers, policy makers, and other stakeholders involved in nutrient management to improve our ability to balance nutrient budgets and to use that understanding to grow abundant food while avoiding pollution.
Key Points
Sustainable nutrient management, a major challenge of this century, requires better quantification of nutrient budgets
This paper reviews major challenges in defining, quantifying, and applying nutrient budgets on multiple system and spatial scales
The improvement and limitation in nutrient budgets need to be communicated among researchers and stakeholders to enable positive changes
The current study investigated the efficacy of a probiotic mixture on ameliorating heat stress-induced impairment of intestinal microflora, morphology, and barrier integrity in broilers. The ...probiotic mixture contained Bacillus licheniformis, Bacillus subtilis, and Lactobacillus plantarum. Three hundred sixty 21-d-old Ross 308 male broilers were allocated in 4 experimental treatments, each of which was replicated 6 times with 15 broilers per replicate. A 2 × 2 factorial design was used in the study, and the main factors were composed of diet (basal diet or addition of 1.5 g/kg of probiotic mixture) and temperature (thermoneutral zone or heat stress). From d 22 to 42, birds were either raised in a thermoneutral zone (22°C) or subjected to cyclic heat stress by exposing them to 33°C for 10 h (from 0800 to 1800) and 22°C from 1800 to 0800. Compared with birds kept in the thermoneutral zone, birds subjected to heat stress had reduced ADG and ADFI; lower viable counts of Lactobacillus and Bifidobacterium and increased viable counts of coliforms and Clostridium in small intestinal contents; shorter jejunal villus height, deeper crypt depth, and lower ratio of villus height to crypt depth; decreased jejunal transepithelial electrical resistance and a higher level of jejunal paracellular permeability of fluorescein isothiocyanate dextran 4 kDa; and downregulated protein levels of occludin and zonula occludens-1 (P < 0.05). Supplemental probiotics increased (P < 0.05) small intestinal Lactobacillus and Bifidobacterium, jejunal villus height, protein level of occludin, and decreased (P < 0.05) feed to gain ratio and small intestinal coliforms. These results indicate that dietary addition of probiotic mixture was effective in partially ameliorating intestinal barrier function. But no temperature × diet interaction was observed in the present study, revealing that the supplemented probiotics had the same effect at both temperatures.
Abstract
Relativistic fermions in topological quantum materials are characterized by linear energy–momentum dispersion near band crossing points. Under magnetic fields, relativistic fermions acquire ...Berry phase of
π
in cyclotron motion, leading to a zeroth Landau level (LL) at the crossing point, a signature unique to relativistic fermions. Here we report the unusual interlayer quantum transport behavior resulting from the zeroth LL mode observed in the time reversal symmetry breaking type II Weyl semimetal YbMnBi
2
. The interlayer magnetoresistivity and Hall conductivity of this material are found to exhibit surprising angular dependences under high fields, which can be well fitted by a model, which considers the interlayer quantum tunneling transport of the zeroth LL's Weyl fermions. Our results shed light on the unusual role of zeroth LLl mode in transport.
Circular RNAs (circRNAs) have been identified as important regulators in regulating cancer progression. The study aims to investigate the expression of circular RNA_LARP4 (circ LARP4) and clinical ...significance in ovarian cancer (OC).
The expression of circ LARP4 was detected in a total of 78 paired ovarian cancer tissue and adjacent normal tissue samples using quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR) analyses. The chi-square test was used to assess the association between expression of circLARP4 and clinical-pathological parameters. Survival plot was evaluated using the Kaplan-Meier method. The multivariate Cox analysis model was used for tumor prognosis analysis.
We identified that circLARP4 expression was significantly down-regulated in ovarian cancer tissues compared with corresponding controls. Furthermore, we found that circLARP4 expression was significantly associated with International Federation of Gynecology and Obstetrics (FIGO) stage and lymph node metastases. Lower circLARP4 expression was associated with poor prognosis of OC patients. Moreover, multivariate Cox analysis showed that lower circLARP4 was an independent risk for OC prognosis.
These results indicated that circLARP4 expression was lower and highlighted that circLARP4 was identified as a potential biomarker of ovarian cancer prognosis.
Although the magnetoelectric effects - the mutual control of electric polarization by magnetic fields and magnetism by electric fields, have been intensively studied in a large number of inorganic ...compounds and heterostructures, they have been rarely observed in organic materials. Here we demonstrate magnetoelectric coupling in a metal-organic framework (CH3)2NH2Mn(HCOO)3 which exhibits an order-disorder type of ferroelectricity below 185 K. The magnetic susceptibility starts to deviate from the Curie-Weiss law at the paraelectric-ferroelectric transition temperature, suggesting an enhancement of short-range magnetic correlation in the ferroelectric state. Electron spin resonance study further confirms that the magnetic state indeed changes following the ferroelectric phase transition. Inversely, the ferroelectric polarization can be improved by applying high magnetic fields. We interpret the magnetoelectric coupling in the paramagnetic state in the metal-organic framework as a consequence of the magnetoelastic effect that modifies both the superexchange interaction and the hydrogen bonding.
Summary
Some patients with osteoporotic vertebral compression fractures still suffer from back pain after percutaneous vertebroplasty. We have found that osteoporotic vertebral compression fractures ...with thoracolumbar fascia injury are common and that thoracolumbar fascia injury may account for the residual pain after percutaneous vertebroplasty.
Purpose
Osteoporotic vertebral compression fractures are successfully treated with percutaneous vertebroplasty (PVP). However, some patients still suffer from back pain after the procedure. We hypothesized that there is a relationship between thoracolumbar (TL) fascia injury and residual postoperative pain.
Methods
This prospective study included 133 elderly patients (age range 55 – 92 years) with osteoporotic vertebral compression fractures treated with PVP from February 2010 to March 2012 in our hospital. The patients were divided into two groups based on the presence of TL fascia injury. A visual analog scale (VAS) and the Chinese modified Oswestry Disability Index were used to evaluate the pain before and after PVP.
Results
The mean VAS score and the Chinese modified Oswestry Disability Index in the patients with TL fascia injury were reduced from 9.11 ± 0.76 to 6.4 ± 1.1 and 73.93 ± 1.46 % to 44.6 ± 3.1 %, respectively, and in the patients without TL fascia injury from 9.26 ± 0.82 to 8.0 ± 1.3 and 73.96 ± 1.38 % to 51.7 ± 1.8 %, respectively. Pain and disability were reduced more in patients without TL fascia injury than in those with TL fascia injury (both
p
< 0.05).
Conclusions
There may be a relationship between TL fascia injury and residual back pain after PVP.
Abstract Background and aim Atherosclerosis is a chronic inflammatory disease and previous studies have demonstrated that anthocyanin inhibits atherosclerosis. In the present study, we explored the ...effects of anthocyanins on inflammatory cytokines in hypercholesterolemic adults and cell lines. Methods and results A total of 150 subjects with hypercholesterolemia consumed a purified anthocyanin mixture (320 mg/d) or a placebo twice a day for 24 weeks in a randomized, double-blind trial. Anthocyanin consumption significantly decreased the levels of serum high sensitivity C-reactive protein (hsCRP) (−21.6% vs. −2.5%, P = 0.001), soluble vascular cell adhesion molecule-1 (sVCAM-1) (−12.3% vs. 0.4%, P = 0.005) and plasma IL-1β (−12.8% vs. −1.3%, P = 0.019) compared to the placebo. We also found a significant difference in the LDL-cholesterol (−10.4% vs. 0.3%, P = 0.030) and HDL-cholesterol level changes (14.0% vs. −0.9%, P = 0.036) between the two groups. In cell culture assays in vitro, purified anthocyanin mixture, delphinidin-3-Ο-β-glucoside (Dp-3g) and cyanidin-3-Ο-β-glucoside (Cy-3g) inhibited IL-6 and IL-1β-induced CRP production ( P < 0.05) in HepG2 cell line and LPS-induced VCAM-1 secretion ( P < 0.05) in porcine iliac artery endothelial cell line respectively in a dose-dependent manner. In addition, the reduction of inflammatory cytokines associated with anthocyanin mixture was stronger when compared with the effects of Dp-3g and Cy-3g separately ( P < 0.05). Conclusions Anthocyanin mixture reduced the inflammatory response in hypercholesterolemic subjects. In addition, different anthocyanin compounds were found to have additive or synergistic effects in mediating anti-inflammatory responses in vitro cell culture assays.
Prolonged and severe hypoxia is the main cause of death of transplanted cells prior to the establishment of functional circulation. In situ generation of oxygen by oxygen-producing scaffolds—a unique ...solution that could produce and deliver oxygen to the adjacent cells independently of blood perfusion—has attracted considerable attention to enhance the survivability of the transplanted cells. However, the application of oxygen-generating scaffolds for facilitating cell survival in pulp-like tissue regeneration is yet to be explored. In this study, gelatin methacryloyl (GelMA)—a biocompatible scaffolding material that closely mimics the native extracellular matrix and is conducive to cell proliferation and differentiation—was used to fabricate oxygen-generating scaffolds by loading various concentrations of CaO2. The CaO2 distribution, topography, swelling, and pore size of CaO2-GelMA hydrogels were characterized in detail. The release of O2 by the scaffold and the viability, spreading, and proliferation of stem cells from apical papilla (SCAPs) encapsulated in the GelMA hydrogels with various concentrations of CaO2 under hypoxia were evaluated. In addition, cellular constructs were engineered into root canals, and cell viability within the apical, middle, and coronal portions was assessed. Our findings showed that 0.5% CaO2-GelMA was sufficient to supply in situ oxygen for maintaining the embedded SCAP viability for 1 wk. Furthermore, the 0.5% CaO2-GelMA hydrogels improved the survivability of SCAPs within the coronal portion of the engineered cellular constructs within the root canals. This work demonstrated that 0.5% CaO2-GelMA hydrogels offer a potential promising scaffold that enhances survival of the embedded SCAPs in endodontic regeneration.
We present a new type of colossal magnetoresistance (CMR) arising from an anomalous collapse of the Mott insulating state via a modest magnetic field in a bilayer ruthenate, Ti-doped ...Ca_{3}Ru_{2}O_{7}. Such an insulator-metal transition is accompanied by changes in both lattice and magnetic structures. Our findings have important implications because a magnetic field usually stabilizes the insulating ground state in a Mott-Hubbard system, thus calling for a deeper theoretical study to reexamine the magnetic field tuning of Mott systems with magnetic and electronic instabilities and spin-lattice-charge coupling. This study further provides a model approach to search for CMR systems other than manganites, such as Mott insulators in the vicinity of the boundary between competing phases.
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