Within-field variability of crop yield levels has been extensively investigated, but the spatial variability of crop yield
responses
to agronomic treatments is less understood. On-farm precision ...experimentation (OFPE) can be a valuable tool for the estimation of in-field variation of optimal input rates and thus improve agronomic decisions. Therefore, the objectives of this study were to investigate the spatial variability of optimal input rates in OFPE and the potential economic benefit of site-specific input management. Mixed geographically weighted regression (GWR) models were used to estimate local yield response functions. The methodology was applied to investigate the spatial variability in corn response to nitrogen and seed rates in four cornfields in Illinois, USA. The results showed that spatial heterogeneity of model parameters was significant in all four fields evaluated. On average, the RMSE of the fitted yield decreased from 1.2 Mg ha
−1
in the non-spatial global model to 0.7 Mg ha
−1
in the GWR model, and the r-squared increased from 10 to 68%. The average potential gain of using optimized uniform rates of seed and nitrogen was US$ 65.00 ha
−1
, while the added potential gain of the site-specific application was US$ 58.00 ha
−1
. The combination of OFPE and GWR proved to be an effective tool for testing precision agriculture’s central hypothesis of whether optimal input application rates display adequate spatial variability to justify the costs of the variable rate technology itself. The reported results encourage more research on response-based input management recommendations instead of the still widespread focus on yield-based algorithms.
Protein-restricted (PR), high-carbohydrate diets improve metabolic health in rodents, yet the precise dietary components that are responsible for these effects have not been identified. Furthermore, ...the applicability of these studies to humans is unclear. Here, we demonstrate in a randomized controlled trial that a moderate PR diet also improves markers of metabolic health in humans. Intriguingly, we find that feeding mice a diet specifically reduced in branched-chain amino acids (BCAAs) is sufficient to improve glucose tolerance and body composition equivalently to a PR diet via metabolically distinct pathways. Our results highlight a critical role for dietary quality at the level of amino acids in the maintenance of metabolic health and suggest that diets specifically reduced in BCAAs, or pharmacological interventions in this pathway, may offer a translatable way to achieve many of the metabolic benefits of a PR diet.
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•Protein-restricted (PR) and branched-chain amino acid (BCAA)-restricted diets improve metabolic health•Decreasing dietary BCAAs recapitulates many of the benefits of a PR diet•Low BCAA diet improves metabolic health independently from changes in energy balance•Dietary protein quality regulates metabolic health independently from protein quantity
Protein-restricted (PR) diets improve metabolic health in mice. Fontana et al. find that PR diets improve metabolic health in humans and that a specific reduction in the consumption of three branched-chain amino acids (BCAAs)—leucine, isoleucine, and valine—by mice improves many aspects of glycemic control and body composition to the same extent as reducing all dietary amino acids.
Conversational artificial intelligence (AI) is changing the way mental health care is delivered. By gathering diagnostic information, facilitating treatment, and reviewing clinician behavior, ...conversational AI is poised to impact traditional approaches to delivering psychotherapy. While this transition is not disconnected from existing professional services, specific formulations of clinician-AI collaboration and migration paths between forms remain vague. In this viewpoint, we introduce four approaches to AI-human integration in mental health service delivery. To inform future research and policy, these four approaches are addressed through four dimensions of impact: access to care, quality, clinician-patient relationship, and patient self-disclosure and sharing. Although many research questions are yet to be investigated, we view safety, trust, and oversight as crucial first steps. If conversational AI isn't safe it should not be used, and if it isn't trusted, it won't be. In order to assess safety, trust, interfaces, procedures, and system level workflows, oversight and collaboration is needed between AI systems, patients, clinicians, and administrators.
Colorectal cancer is a global disease with increasing incidence. Mortality is largely attributed to metastatic spread and therefore, a mechanistic dissection of the signals which influence tumor ...progression is needed. Cancer stroma plays a critical role in tumor proliferation, invasion and chemoresistance. Here, we sought to identify and characterize exosomal microRNAs as mediators of stromal-tumor signaling.
, we demonstrated that fibroblast exosomes are transferred to colorectal cancer cells, with a resultant increase in cellular microRNA levels, impacting proliferation and chemoresistance. To probe this further, exosomal microRNAs were profiled from paired patient-derived normal and cancer-associated fibroblasts, from an ongoing prospective biomarker study. An exosomal cancer-associated fibroblast signature consisting of microRNAs 329, 181a, 199b, 382, 215 and 21 was identified. Of these, miR-21 had highest abundance and was enriched in exosomes. Orthotopic xenografts established with miR-21-overexpressing fibroblasts and CRC cells led to increased liver metastases compared to those established with control fibroblasts. Our data provide a novel stromal exosome signature in colorectal cancer, which has potential for biomarker validation. Furthermore, we confirmed the importance of stromal miR-21 in colorectal cancer progression using an orthotopic model, and propose that exosomes are a vehicle for miR-21 transfer between stromal fibroblasts and cancer cells.
The use of winter cover crops (WCC) such as hairy vetch (Vicia villosa Roth) and cereal rye (Secale cereale L.), in a corn (Zea mays L.)-soybean Glycine max (L.) Merr. rotation provides long-term ...benefits that are generally overlooked. There is a particular lack of information regarding the effects of WCC on soil physical and chemical properties. The objective of this study was to assess the effects of four crop sequences (C/S, corn-fallow/soybean-fallow; C-R/S-R, corn-rye/soybean-rye; C-R/S-V, corn-rye/soybean-vetch; and C-R/S-VR, corn-rye/soybean-vetch and rye) under no-till on several soil physical and chemical properties. Soil chemical properties included soil organic matter (SOM), pH, total nitrogen (TN), nitrates (NO₃-N), and available phosphorus (P). The analyzed soil physical properties analyzed were: water-aggregate stability (WAS), bulk density (D(b)), penetration resistance (PR), total porosity (TP), pore-size distribution, water retention properties, and saturated hydraulic conductivity (K(sat)). The experimental design was a split-split-plot where whole-plot treatments (sampling period) had a Latin square design and subplot treatments (crop sequences) were arranged in a randomized complete block design with four replications. Compared with winter fallow, crop sequences that included WCC provided substantial benefits from the soil productivity standpoint. Specifically, the use of the C-R/S-V or C-R/S-VR increased SOM down to 30 cm. All WCC sequences improved WAS with increases of 9, 13, and 17% for C-R/S-R, C-R/S-V, and C-R/S-VR, respectively. Winter cover crop sequences reduced D(b) and PR of the soil surface and increased total and storage porosity along with plant available water. While the C-R/S-V sequence was the most effective in reducing soil NO₃-N, the C-R/S-R sequence was the most effective in fixing soil P.
A trans-N-heterocyclic carbene (NHC) platinum(II) acetylide complex bearing phenyl acetylene ligands (NPtPE1) has been synthesized via the Hagihara reaction in 64% yield. The complex features ...spectrally narrow deep blue emission with a phosphorescence quantum yield (0.30) and lifetime (∼10 μs) in the solid state. The modest quantum yield and lifetime make NPtPE1 a candidate for incorporation into an organic light emitting diode (OLED). Prototype devices exhibited a maximum EQE of 8% with CIE (0.20,0.20). To the best of our knowledge, this is the first example of a platinum(II) acetylide bearing NHC ligands to be incorporated into an OLED.
A series of 11 complexes of the type trans-(NHC)2Pt(CC-Ar)2 (where NHC = N-heterocyclic carbene) have been synthesized and their photophysics characterized. The complexes display moderately ...efficient deep blue to green phosphorescence from a triplet excited state that is localized mainly in the aryl acetylide ligand (CC-Ar). The emission energy varies with the substituent on CC-Ar, with the highest energy emission for Ar = 4-pyridyl. The emission quantum efficiency and lifetime for the series decreases with increasing emission energy (E em), and the effect is identified as arising from an increase in the nonradiative decay rate (k nr) with E em. Temperature-dependent emission lifetime studies for three complexes give activation energies for the nonradiative decay process ∼1000 cm–1, and the thermally activated decay process is attributed to crossing to a nonemissive metal-centered (d–d) excited state. At a low temperature, two different emission progressions are observed. Density functional theory calculations suggest that the triplet energy varies with the torsion of the aryl acetylide rings relative to the plane defined by the PtC4 unit (where C = the carbon atoms bonded to Pt). The multiple emission is ascribed to emission from complexes differing with respect to the aryl acetylide ring torsion. Ultrafast transient absorption spectroscopy reveals a fast relaxation (∼5 ps) that may also be due to aryl acetylide ring torsional relaxation in the triplet excited state.
The degree of interaction between the ventral and dorsal visual streams has been discussed in multiple scientific domains for decades. Recently, several white matter tracts that directly connect ...cortical regions associated with the dorsal and ventral streams have become possible to study due to advancements in automated and reproducible methods. The developmental trajectory of this set of tracts, here referred to as the posterior vertical pathway (PVP), has yet to be described. We propose an input-driven model of white matter development and provide evidence for the model by focusing on the development of the PVP. We used reproducible, cloud-computing methods and diffusion imaging from adults and children (ages 5–8 years) to compare PVP development to that of tracts within the ventral and dorsal pathways. PVP microstructure was more adult-like than dorsal stream microstructure, but less adult-like than ventral stream microstructure. Additionally, PVP microstructure was more similar to the microstructure of the ventral than the dorsal stream and was predicted by performance on a perceptual task in children. Overall, results suggest a potential role for the PVP in the development of the dorsal visual stream that may be related to its ability to facilitate interactions between ventral and dorsal streams during learning. Our results are consistent with the proposed model, suggesting that the microstructural development of major white matter pathways is related, at least in part, to the propagation of sensory information within the visual system.
MicroRNAs (miRNAs) are a class of small highly conserved RNAs that provide widespread expressional control through the translational repression of mRNA. MiRNAs have fundamental roles in the ...regulation of intracellular processes, and their importance during malignant transformation and metastasis is becoming increasingly well recognized. An important event in the metastatic cascade is epithelial to mesenchymal transition (EMT), a reversible phenotypic switch over, which endows malignant epithelial cells with the capacity to break free from one another and invade the surrounding stroma. Our understanding of EMT has been significantly improved by the characterization of miRNAs that influence the signalling pathways and downstream events that define EMT on a molecular level.
Here, we detail the role of miRNAs in EMT, and in doing so demonstrate their importance in the early stages of the metastatic cascade; we discuss a significant body of data that suggest new opportunities for drug development, and we highlight critical knowledge gaps that remain to be addressed.
Small highly conserved non‐coding microRNAs (miRNAs) regulate the expression of a wide range of genes involved in tumourogenesis and metastasis. Epithelial to Mesenchymal Transition (EMT) and the reverse process Mesenchymal to Epithelial Transition (MET) are key events in the metastatic cascade suggesting that plasticity is a prerequisite for cancer cells capable of completing the metastatic journey. Here we demonstrate that miRNAs are crucial regulators of EMT and that their pleotropic actions during EMT and MET have important consequences for cancer progression.
Objective To investigate the self-reported confidence and preparedness of final year undergraduate students in undertaking a range of clinical procedures.Methods A questionnaire was distributed to ...final year dental students at Cardiff University, six months prior to graduation. Respondents rated their confidence in undertaking 39 clinical procedures using a 5-point scale (1 = can undertake on own with confidence, 5 = unable to undertake). Students also responded yes/no to experiencing four difficulties and to three statements about general preparedness.Results 71% (N = 51) responded of which 55% (N = 28) were female. Over half reported being 'anxious that the supervisor was not helping enough' (57%) and 'relying heavily on supervisor for help' (53%). Eighty percent 'felt unprepared for the clinical work presented' and gender differences were most notable here (male: 65% N = 33; females: 93% N = 47). Mean confidence scores were calculated for each clinical procedure (1 = lowest; 5 = highest). Confidence was highest in performing 'simple scale' and 'fissure sealant' (mean-score = 5). Lowest scores were reported for 'surgical extractions involving a flap (mean-score = 2.28)', 'simple surgical procedures' (mean-score = 2.58) and the 'design/fit/adjustment of orthodontic appliances' (mean-score = 2.88).Conclusions As expected complex procedures that were least practised scored the lowest in overall mean confidence. Gender differences were noted in self-reported confidence for carrying out treatment unsupervised and feeling unprepared for clinical work.
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