bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hydrologic Extremes and Legacy Sources Can Override Efforts to Mitigate Nutrient and Sediment Losses at the Catchment Scale
Authors: Bieroza Magdalena , Bergström Lars , Ulén Barbro , Djodjic Faruk , Tonderski Karin , Heeb Anuschka , Svensson Jonas , Malgeryd Johan 
Published: June 2019

Combating eutrophication requires changes in land and water management in agricultural catchments and implementation of mitigation measures to reduce phosphorus (P), nitrogen (N) and suspended sediment (SS) losses. To date, such mitigation measures have been built in many agricultural catchments, but there is a lack of studies evaluating their effectiveness. Here we evaluated the effectiveness of mitigation measures in a clay soil‐dominated headwater catchment by combining the evaluation of long‐term and high‐frequency data with punctual measurements upstream and downstream of three mitigation measures: lime‐filter drains, a two‐stage ditch, and a sedimentation pond. Long‐term hydrochemical data at the catchment outlet showed a significant decrease in P (−15%) and SS (−28%) and an increase in nitrate nitrogen (NO3–N, +13%) concentrations. High‐frequency (hourly) measurements with a wet‐chemistry analyzer (total and reactive P) and optical sensor (NO3–N and SS) showed that the catchment is an abundant source of nutrients and sediments and that their transport is exacerbated by prolonged drought and resuspension of stream sediments during storm events. Lime‐filter drains showed a decrease in SS by 76% and total P by 80% and an increase in NO3–N by 45% compared with traditional drains, potentially indicating pollution swapping. The effectiveness of two‐stage ditch and sedimentation pond was less evident and depended on the prevalent hydrometeorological conditions that drove the resuspension of bed sediments and associated sediment‐bound P transport. These results suggest that increased frequency of prolonged drought due to changing weather patterns and resuspension of SS and sediment‐bound P during storm events can override the generally positive effect of mitigation measures.Core Ideas
We assessed the efficiency of catchment mitigation measures to reduce water pollution.
At the catchment outlet, concentrations of P and sediments decreased by 15 and 28%.
Lime‐filter drains reduced P and sediments by 80% but increased nitrate by 45%.
Prolonged drought and resuspension of sediments exacerbated stream nutrient export.
High‐frequency data show that legacy sources can override mitigation efforts.
Daily Light Integral Requirement of a Creeping Bentgrass Putting Green as Affected by Shade, Trinexapac‐ethyl, and a Plant Colorant
Authors: Russell Travis R. , Karcher Douglas E. , Richardson Michael D. 
Published: June 2019

ABSTRACTTurfgrass quality is often limited by the availability of photosynthetically active radiation (PAR) delivered to the turf surface. The cumulative PAR at a given site during 1 d is termed the daily light integral (DLI) and is an effective measurement for quantifying light requirements for various turfgrass systems. The minimum DLI necessary to maintain acceptable quality on creeping bentgrass (Agrostis stolonifera L.) putting greens has yet to be determined. Shade timing, trinexapac‐ethyl growth regulator, and ultraviolet‐absorbing plant colorant applications may affect the DLI requirement of creeping bentgrass putting greens. The objective of this research was to determine the DLI requirement of a creeping bentgrass putting green by evaluating the effects of shade intensity and timing, as well as the influence of trinexapac‐ethyl and a plant colorant on turfgrass quality and coverage. Intensity treatments of 0, 70, 80, and 90% shade were applied during either morning (sunrise to solar noon) or afternoon (solar noon to sunset) hours from May through October 2016 and 2017 on a ‘Tyee’ creeping bentgrass, sand‐based putting green. Evaluations of visual turf quality and turf coverage were performed every 2 wk. After 2 yr, the DLI requirement to maintain acceptable putting green quality was estimated to be 30 mol m−2 d−1. Although effective in improving turf quality at times during summer months, trinexapac‐ethyl and the plant colorant did not significantly reduce the DLI requirement.
Pentaploid Apomicts by Interspecific Hybridization between Diploid Urochloa ruziziensis and Tetraploid Apomictic U. decumbens
Authors: Nitthaisong Pattama , Ishigaki Genki , Suenaga Kazuhino , Muguerza Melody , Tanaka Hidenori , Akashi Ryo 
Published: June 2019

ABSTRACTUrochloa species are a rich source of quality forage in the tropical and subtropical areas, and cultivated species are predominantly facultative apomictic. They are well adapted to poor soil conditions, resistant to heavy grazing, and drought tolerant, but some Urochloa species produce poor pasture and seed yield. Therefore, it is important to complement and to combine characteristics of different species in breeding programs. We have conducted interspecific crosses between diploid U. ruziziensis (R. Germ. & C. M. Evrard) Crins ‘Kennedy’ (2n = 2x = 18) with apomictic tetraploids U. decumbens (Stapf) R. D. Webster ‘Basilisk’ (2n = 4x = 36) and U. brizantha (Hochst. ex A. Rich.) R. D. Webster ‘Marandu’ (2n = 4x = 36). Diploid, triploid, and tetraploid plants were obtained from these crosses. The triploid plants were further crossed with ‘Basilisk’ to produce a BC1F1 generation. Although no seeds were produced by self‐pollination of the F1 triploid hybrids, backcrossing eventually produced triploid, tetraploid, and pentaploid plants (BC1F1). Only the pentaploid plants produced seeds by self‐pollination. This is the first report of the production of apomictic pentaploid progenies from interspecific crosses in Urochloa.
Cover Crops and Compost Influence Soil Enzymes during Six Years of Tillage‐Intensive, Organic Vegetable Production
Authors: Brennan Eric B. , Acosta-Martinez Veronica 
Published: June 2019

Core Ideas
There were large differences in soil enzyme activities within organic systems.
Compost and annual cover crops increased activities of most soil enzymes.
Activities of most soil enzymes were correlated with microbial biomass.
Cover crop type did not influence soil enzyme activities.
The results show the soil health benefits of frequent cover crops in vegetable systems
Soil enzymes are considered sensitive indicators of soil health but are not well understood in tillage‐intensive vegetable systems. The activities of soil enzymes involved in nutrient cycling (β‐glucosidase, β‐glucosaminidase, alkaline phosphatase, dehydrogenase, aspartase, and L‐asparaginase) were evaluated during 6 yr of commercial‐scale production in five organic vegetable systems in Salinas, CA. The systems differed in yard‐waste compost inputs (none or 15.2 Mg ha–1 yr–1), winter cover crop frequency (annually or every fourth year), and cover crop type (legume‐rye, mustard, or rye). Large differences in cumulative organic matter input (7.4 to 136.8 Mg ha–1) from compost and cover crop shoots affected soil enzyme activities. With exception of aspartase, all enzyme activities were on average lowest without compost, intermediate with compost and infrequent cover cropping, and highest with compost and annual cover cropping. After 6 yr of vegetable production there was a positive relationship between microbial biomass and activities of all enzymes except aspartase. Despite lower inputs of cover crop shoot biomass from mustard compared with rye and the legume‐rye, and differences in shoots residue quality, cover crop type had relatively little influence on enzyme activities. We conclude that soil enzyme activities were influenced primarily by annual cover cropping. These results and other attributes of soil health in this long‐term study illustrate the importance of frequent cover cropping in tillage‐intensive vegetable production. This raises questions about the sustainability of organic and conventional vegetable systems if cover crops are seldom used, and highlights the need for innovative strategies to increase cover cropping.
Validation of Soil‐Test‐Based Phosphorus and Potassium Fertilizer Recommendations for Irrigated Soybean
Authors: Fryer Matthew S. , Slaton Nathan A. , Roberts Trenton L. , Ross W. Jeremy 
Published: June 2019

Core Ideas
The most common soil‐test‐based fertilization recommendation error is a false positive.
Surface soil sample P and K concentrations are qualitative indicators of subsoil P and K concentrations.
The R2‐stage, leaflet‐K concentration of irrigated soybean is an accurate indicator of yield responsiveness to K fertilization.
Soil testing is the best available technology for making crop fertilizer recommendations, and precision agriculture has increased the demand for soil‐testing. Our primary research objectives were to validate the accuracy of soil‐test P (STP) and K (STK) availability (Mehlich‐3) and trifoliolate leaflet‐P and leaflet‐K concentration interpretations for predicting irrigated‐soybean [Glycine max (L.) Merr.] yield response to P and K fertilization at 22 site‐years. Each trial contained six treatments involving two P rates and four K rates including a no fertilizer‐P or ‐K control and the soil‐test recommendation. Yield and tissue nutrient concentration responses were assessed at three significance levels (p ≤ 0.05, p ≤ 0.10, or p ≤ 0.25) and identified as correct or incorrect according to the response predicted by soil‐test recommendations. The accuracy of soil and tissue analyses to predict the correct plant response to fertilization increased as the significance level moved from conservative (p ≤ 0.05) to liberal (p ≤ 0.25). Mehlich‐3 STP accurately identified soils that did not respond to fertilizer P and had an overall accuracy of 40 (p ≤ 0.05) to 48% (p ≤ 0.25) in predicting yield response to fertilization. Existing STK interpretations were 72 (p ≤ 0.05) to 82% (p ≤ 0.25) accurate. Critical leaflet‐K concentrations accurately identified soybean response to K fertilization at 46 (p ≤ 0.05) to 60% (p ≤ 0.25) of the sites. Interpretation errors were most common in the very low and low STP levels, low and medium STK levels, and the low tissue‐K level. The accuracy of the soil and tissue testing and their interpretation process were reasonably accurate for K but substantial improvements are needed for P.
Investigation of Gravity‐Driven Infiltration Instabilities in Smooth and Rough Fractures Using a Pairwise‐Force Smoothed Particle Hydrodynamics Model
Authors: Shigorina Elena , Tartakovsky Alexandre M. , Kordilla Jannes 
Published: June 2019

Core Ideas
We study infiltration dynamics in smooth and rough fractures using a 3D SPH model.
Roughness induces the formation of flow fingering and preferential flow paths.
Fractal roughness leads to a deceleration of average fingertip velocities.
The velocity variance of fingers positively correlates with the degree of roughness.
Normalized finger velocity and length scale in accordance with analytical predictions.
This work investigates small‐scale infiltration dynamics in smooth and rough single fractures using a three‐dimensional multiphase pairwise‐force smoothed particle hydrodynamics (PF‐SPH) model. Gravity‐driven infiltration instabilities in fractures under unsaturated conditions can significantly influence the arrival time of tracers or contaminants, and the rapid and localized recharge dynamics in fractured–porous aquifer systems. Here, we study the influence of roughness and injection rate on fluid flow modes and flow velocity. Three types of fractures are considered with different degrees of roughness, including a smooth fracture. Both the rough and smooth fractures exhibit flow instabilities, fingering, and intermittent flow regimes for low infiltration rates. In agreement with theoretical predictions, a flat fluid front is achieved when the flux q supplied to a fracture is larger than the gravitationally driven saturated flux [q > kρg/μcos(φ), where k is the intrinsic permeability of the fracture, ρ is a density, μ is the viscosity, and φ is the fracture inclination angle measured from the vertical direction]. To characterize the flow instability, we calculate standard deviations of velocity along the fracture width. For the considered infiltration rates, we find that an increase in roughness decreases the flow velocity and increases the standard deviation of velocity. This is caused by a higher likelihood of flow discontinuities in the form of fingering and/or snapping rivulets. To validate our unsaturated flow simulations in fractures, we estimate the scaling of specific discharge with normalized finger velocity, compute the relationship between fingertip length and scaled finger velocity, and find good agreement with experimental results.
Hydraulic‐Mechanical Properties of Unsaturated Granite‐Weathered Residual Soil in Korea
Authors: Pham Khanh , Kim Dongku , Lee In‐Mo , Choi Hangseok 
Published: June 2019

Core Ideas
We examine SWCC and shear strength under various stress states and suction levels.
Relevant effective stress for granite‐weathered residual soil in Korea is proposed.
We propose a numerical framework for strength analysis with transient infiltration.
Potential failure mechanisms of civil infrastructure under rainfall are explored.
We suggest using stress‐dependent SWCC in strength analysis.
This study performed a series of experiments to examine the hydraulic‐mechanical properties of granite‐weathered residual soil in the Korean Peninsula. Particular attention was paid to the soil‐water characteristic curve (SWCC) and shear strength under various stress states and matric suction levels. The experimental results indicated the decisive influence of the stress state on the SWCC, notably in the low range of matric suction. In addition, the evolution of shear strength with suction became significant under high net confining stress. The effective stress using the stress‐independent SWCC could not describe the actual mechanical behaviors of the unsaturated soil. The relevant effective stress for the granite‐weathered residual soil in consideration was then proposed. Next, a numerical framework for strength analysis with infiltration was developed to manifest the practical applications of the experimental results. The analysis results revealed the potential failure mechanisms of the geotechnical infrastructures induced by rainfall. Ignoring the contribution of matric suction may lead to overly conservative outcomes and cannot capture the realistic performance of soil under the rainfall condition. Moreover, the stress‐dependent hydraulic properties are suggested for application in strength analysis for the safer design of geotechnical infrastructure.
New Sensor Technology for Field‐Scale Quantification of Carbon Dioxide in Soil
Authors: Lazik Detlef , Vetterlein Doris , Salas Simone Kilian , Sood Pramit , Apelt Bernd , Vogel Hans‐Jörg 
Published: June 2019

Core Ideas
This new technology is suitable for field‐scale quantification of CO2 in soil.
The measurement scale ranges from decimeters up to decameters.
The concentrations from the soil water and air phases are averaged.
Transient CO2 production and transport reflect plant growth.
Biological activity in soil causes fluxes of O2 into and CO2 out of the soil with significant global relevance. Hence, the dynamics of CO2 concentrations in soil can be used as an indicator for biological activity. However, there is an enormous spatial and temporal variability in soil respiration, which has led to the notion of hotspots and hot moments. This variability is attributed to the spatiotemporal heterogeneity of both plant–soil–microbiome interactions and the local conditions governing gas transport. For the characterization of a given soil, the local heterogeneities should be replaced by some meaningful average. To this end, we introduce a line sensor based on tubular gas‐selective membranes that is applicable at the field scale for a wide range in water content. It provides the average CO2 concentration of the ambient soil along its length. The new technique corrects for fluctuating external conditions (i.e., temperature and air pressure) and the impact of water vapor without any further calibration. The new line sensor was tested in a laboratory mesocosm experiment where CO2 concentrations were monitored at two depths during the growth of barley (Hordeum vulgare L.). The results could be consistently related to plant development, plant density, and changing conditions for gas diffusion toward the soil surface. The comparison with an independent CO2 sensor confirmed that the new sensor is actually capable of determining meaningful average CO2 concentrations in a natural soil for long time periods.
Analysis of the role of climatic and human factors in runoff variations (case study: Lighvan River in Urmia Lake Basin, Iran)
Authors: Kanani R. , Fard A. Fakheri , Ghorbani M. A. , Dinpashoh Y. 
Published: June 2019

Abstract
In recent years, river flows have significantly decreased due to regional or global climate change and human activities, especially in the arid and semi-arid regions. In this study, the effects of climate change and human activities on the runoff responses were examined using hydrologic sensitivity analysis and hydrologic model simulation in the Lighvan basin located in the northwest of Iran. The Mann–Kendall test was applied to identify the trends in hydroclimatic data series. Also, the Pettitt test was used to detect change points in the annual discharge values and climatic variables. The results showed that there was negative trend in discharge data series, and examination of the climatic factors indicated that there was an increase in the temperature values and a decrease in the relative humidity values at the basin. The rapid changes in runoff values and most of the climatic variables occurred in the mid-1990s. The effect percentages of the human factors and climatic factors on runoff reduction in all the models used were 65–84% and 16–35%, respectively. Therefore, the impact of human activities on the river flow changes was significant.
Water safety assessment and spatio-temporal changes in Dongting Lake, China on the basis of water regime during 1980–2014
Authors: Wan Rongrong , Wang Peng , Dai Xue , He Zheng 
Published: June 2019

Abstract
The drastic changes in water regime are of great importance for maintaining water security in lakes with violent seasonal fluctuations. Based on hydrological data of Dongting Lake, the second largest freshwater lake in China, during 1980–2014, a set of water safety assessment methods suitable for seasonal lakes was constructed. Results demonstrated the following. (1) The year 2003 was a major time point for changes in water regime in Dongting Lake between 1980 and 2014. (2) The water regime changes in different parts of Dongting Lake exhibited certain similarities in periodicity and overall change trends. Among them, South Dongting Lake presented the best water security status, followed by East Dongting Lake and West Dongting Lake. (3) Compared with 1980–2002, the complexity of the water safety level change in East Dongting Lake increased in 2003–2014, as manifested in the tendency of the distribution of water safety levels to change sharply. (4) The influence of dry years on the water safety of Dongting Lake was greater than that of rainy years. The multi-time, multi-scale and multi-target lake water safety assessment method based on water regimes provides new ideas and methods for global research on seasonal lake water safety.
The Role of NIR Fluorescence in MDR Cancer Treatment: From Targeted Imaging to Phototherapy
Authors: Wang Zengtao , Meng Qingqing , Li Shaoshun 
Published: June 2019

Background:
Multidrug Resistance (MDR) is defined as a cross-resistance of cancer cells
to various chemotherapeutics and has been demonstrated to correlate with drug efflux pumps. Visualization
of drug efflux pumps is useful to pre-select patients who may be insensitive to chemotherapy,
thus preventing patients from unnecessary treatment. Near-Infrared (NIR) imaging is an attractive
approach to monitoring MDR due to its low tissue autofluorescence and deep tissue penetration.
Molecular NIR imaging of MDR cancers requires stable probes targeting biomarkers with high
specificity and affinity.

Objective:
This article aims to provide a concise review of novel NIR probes and their applications
in MDR cancer treatment.

Results:
Recently, extensive research has been performed to develop novel NIR probes and several
strategies display great promise. These strategies include chemical conjugation between NIR dyes
and ligands targeting MDR-associated biomarkers, native NIR dyes with inherent targeting ability,
activatable NIR probes as well as NIR dyes loaded nanoparticles. Moreover, NIR probes have been
widely employed for photothermal and photodynamic therapy in cancer treatment, which combine
with other modalities to overcome MDR. With the rapid advancing of nanotechnology, various
nanoparticles are incorporated with NIR dyes to provide multifunctional platforms for controlled
drug delivery and combined therapy to combat MDR. The construction of these probes for MDR
cancers targeted NIR imaging and phototherapy will be discussed. Multimodal nanoscale platform
which integrates MDR monitoring and combined therapy will also be encompassed.

Conclusion:
We believe these NIR probes project a promising approach for diagnosis and therapy
of MDR cancers, thus holding great potential to reach clinical settings in cancer treatment.
Expanding the Biotherapeutics Realm via miR-34a: “Potent Clever Little” Agent in Breast Cancer Therapy
Authors: Mohammady Mohsen , Ghetmiri Seyed I. , Baharizade Mahtab , Morowvat Mohammad H. , Torabi Susan 
Published: June 2019

Background:One of the most prevalent cancers befell to women is considered to be breast cancer (BC). It is also the deadliest among the female population after lung cancer. Additionally, several studies have demonstrated that there is an association between microRNA34-a and breast cancer.Method:We searched PubMed, Web of Science, and Google Scholar up to December 2018. Those studies which have been studied miR-34a and its tumor-suppressing capabilities were considered as the most important topics. Moreover, we extracted articles which were solely focused on microRNA-34a in breast cancer therapy. Finally, 80 articles were included.Results:In comparison with the normal tissues, down-regulation of miR-34a expression is shown considerably in tumor cells. Overexpression of miR-34a acts as a tumor suppressor by transcriptional regulating one of the signaling pathways (TP53), NOTCH, and transforming growth factor beta (TGF-β), Bcl- 2 and SIRT1genes, HDAC1 and HDAC7, Fra-1, TPD52, TLR Via CXCL10. Moreover, drug resistance declines which lead to the apoptosis, cell cycle arrest and senescence. As a result, the proliferation, invasion and metastasis of the tumor are suppressed. The Mrx34 drug contains miR-34a mimic and a lipid vector. MiR-34a as the active ingredient portrays the role of a tumor suppressor. This drug has recently entered the clinical trials studies.Conclusion:These findings suggest a robust cause for developing miR-34a as a therapeutic agent to target BC. In that scenario, miR-34a is strongly useful to introduce new therapeutic goals for BC. Moreover, this review aims to confirm the signal pathways, therapeutic and diagnostic values of miR- 34a in BC and beyond.