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A simple, straightforward, and highly efficient greener approach for synthesizing bis(6‐aminouracil‐5‐yl)methane derivatives was developed by employing β‐cyclodextrin‐SO3H as supramolecular catalyst in water at 100 °C. A total of 16 bis(6‐aminouracil‐5‐yl)methanes were synthesized via a one‐pot reaction between substituted aromatic aldehydes, 6‐amino‐1,3‐dimethyluracil, and 10% β‐cyclodextrin‐SO3H in water with 84%–92% yield within 20–120 min. The salient features of this protocol included water as green solvent, β‐cyclodextrin‐SO3H as recyclable supramolecular catalyst, mild reaction conditions, easy isolation of pure products, and good to excellent yields. [ABSTRACT FROM AUTHOR]

Introduction: Delays exist at each stage of the chronic limb‐threatening ischaemia (CLTI) care pathway, but there is little known about patient factors influencing delay to diagnosis of CLTI. This study explores the experiences and perceptions of patients recently diagnosed with CLTI. Methods: A qualitative interview study was conducted. Sixteen participants underwent semi‐structured interviews. Reflexive thematic analysis was performed on the data, aiming to understand factors which can influence delay in the CLTI care pathway. Results: Five interrelated themes were developed: CLTI is a devastating condition; Reluctance to ask for help; When we are empowered we get better care; Luck plays a role in the process to diagnosis; and Vascular units can do better, comprising sub‐themes of information transfer—consider communication and arterial versus non‐arterial centres—proximity isn't everything. Conclusions: The five themes generated from the interview data describe factors relevant to delay given meaning by participants who have lived experience of CLTI. Theme content should be noted by clinicians, commissioners and providers looking to improve care pathways for patients with CLTI. The importance of awareness for the public, patients and clinicians linked ideas in some themes and interventions to raise awareness should be considered. [ABSTRACT FROM AUTHOR]

Introduction: Patients in the community with suspected Chronic limb‐threatening ischaemia (CLTI) should be urgently referred to vascular services for investigation and management. The Theoretical Domains Framework (TDF) allows identification of influences on health professional behaviour in order to inform future interventions. Here, the TDF is used to explore primary care clinicians' behaviours with regards to recognition and referral of CLTI. Methods: Semi‐structured interviews were conducted with 20 podiatrists, nurses and general practitioners in primary care. Directed content analysis was performed according to the framework method. Utterances were coded to TDF domains, and belief statements were defined by grouping similar utterances. Relevance of domains was confirmed according to belief frequency, presence of conflicting beliefs and the content of the beliefs indicating relevance. Results: Nine TDF domains were identified as relevant to primary care clinicians: Knowledge, Environmental context and resources, Memory, Decision and attention processes, Beliefs about capabilities, Skills, Emotions, Reinforcement and Behavioural regulation. Relationships across domains were identified, including how primary care clinician confidence and working in a highly pressurized environment can affect behaviour. Conclusion: We have identified key barriers and enablers to timely recognition and referral behaviour. These beliefs identify targets for theory‐driven behaviour change interventions to reduce delays in CLTI pathways. [ABSTRACT FROM AUTHOR]

Background: Chronic limb-threatening ischaemia (CLTI) is a condition associated with significant risks of lower limb loss and mortality, which increase with delays in management. Guidance recommends urgent referral and assessment, but delays are evident at every stage of the CLTI patient pathway. This study uses qualitative methods to explore hospital clinicians' experiences and perceptions of the existing CLTI pathway. Methods: A qualitative interview study was conducted. Semi-structured interviews were undertaken with 13 clinicians involved in the assessment of patients referred to hospital with suspected CLTI, identified via purposive sampling from English vascular surgery units. Clinicians included podiatrists, vascular specialist nurses and doctors. Reflexive thematic analysis was performed on the data from a critical realist position. Results: The need for speed was the single overarching theme identified. Four linked underlying themes were also identified; 1. Vascular surgery as the poor relation (compared to cancer and other specialties), with a sub-theme of CLTI being a challenging diagnosis. 2. Some patients are more equal than others, with sub-themes of diabetes vs. non-diabetes, hub vs. spoke and frailty vs. non-frail. 3. Life in the National Health Service (NHS) is tough, with sub-themes of lack of resource and we're all under pressure. 4. Non-surgeons can help. Conclusions: The underlying themes generated from the rich interview data describe barriers to timely referral, assessment and management of CLTI, as well as the utility of non-surgical roles such as podiatrists and vascular specialist nurses as a potential solution for delays. The overarching theme of the need for speed highlights the meaning given to adverse consequences of delays in management of CLTI by clinicians involved in its assessment. Future improvement projects aimed at the CLTI pathway should take these findings into account. [ABSTRACT FROM AUTHOR]

A simple, straightforward, and highly efficient approach has been developed to synthesize thioamide derivatives under catalyst‐ and solvent‐free conditions at 100 °C/room temperature. Total 51 thioamides were synthesized via a one‐pot multicomponent Willgerodt‐Kindler reaction between substituted aromatic aldehydes, elemental sulfur powder and amines with 70–98 % yield within 20–70 min using cyclic secondary amines and 1.5–24 h using aliphatic primary and secondary amines. The cyclic secondary amines react faster than aliphatic amines. Twenty‐one newer compounds were prepared and characterized by 1H NMR, 13C NMR, HRMS. Mild reaction conditions, good yields, and a wide range of reactions demonstrate the excellent synthetic utility of this method. The developed protocol showed that there is no need to collect, purify, recycle, and remove the solvent after the reaction is complete. Reaction rates are generally high due to the high availability of reactants, i. e. shortens the reaction time, is environmentally friendly, and which makes the overall process more sustainable and economical. [ABSTRACT FROM AUTHOR]

Droughts are recurring phenomena in the north‐western Himalaya causing severe socioeconomic hardships. Our understanding on temporal and spatial occurrence of such extreme droughts in long‐term perspective is constrained due to limited short‐term weather records. Toward fulfilling such a large data void, we developed a network of ring‐width chronologies of Himalayan cedar from seven moisture stressed high‐elevation sites in Kishtwar, Jammu & Kashmir. Moisture responsive ring‐width chronologies were used to develop the annual Standardized Precipitation Index (SPI from previous year June to current year May (SPI12‐May)) extending back to 1613 CE. The SPI reconstruction revealed annual to decadal‐scale variability in droughts, which strikingly were more frequent and of larger magnitude during 1760s–2017 CE in comparison to the earlier part of the reconstruction (1613–1750s CE). Our SPI12‐May record revealed strong consistency with other tree‐ring‐based hydrological records from the western Himalaya. Spatial correlation analyses revealed strong linkage of the SPI with Tropical Pacific Ocean surface temperature. Key Points: Annual Standardized Precipitation Index from prior year June to current year May was reconstructed for the first time for Jammu & KashmirHigh‐magnitude droughts were found more frequent since later part of LIA (1760s–2017 CE) in comparison to earlier part (1613–1750s CE)Dry periods observed in early part (1613–1750s CE) were shorter in comparison to that in later part of the reconstruction [ABSTRACT FROM AUTHOR]

The spatial and temporal span of hydrological impact of the "Little Ice Age" (LIA) in the north‐western Himalaya is not well constrained due to data limitation. We evaluated a network of tree‐ring chronologies from moisture‐stressed ecological settings in Jammu and Kashmir to identify the impact of LIA over the western Himalaya. Our study reflects three centennial scale phases; the middle phase (1650s–1850s CE) with stable precipitation and in accordance with other hydrological records clearly demarcates the LIA impact over the Himalaya. However, high‐magnitude droughts recorded in early (1383–1650s CE) and late phases (1850s–2017) underpin that the north‐western Himalaya did not witness any LIA influence before 1650s. Plain Language Summary: Here, we present a 635‐year long annual (prior year October to current year September) precipitation reconstruction from Kishtwar, Jammu and Kashmir. A network of 16 tree‐ring chronologies of Himalayan cedar and neoza pine was used in the study. The reconstruction captured three distinct phases in precipitation regime from 1383–1650s, 1650s–1850s, and 1850s–2017 CE and among these, the middle phase (1650s–1850s) showed relatively prolonged pluvial phase with consistently stable precipitation advocating for the active LIA over the western Himalaya. The other two phases reflect high‐amplitude droughts with intervening wet periods contrasting the existence of the LIA‐induced wetting. To validate the reconstruction skill and the LIA effect over the western Himalaya and Central Asia, the present record was compared with the other available precipitation, river flow and hydrological proxy records which support the LIA influenced precipitation during 1650s–1850s CE. Key Points: Three distinct centennial scale phases have been identified in 635 years long precipitation record developed from the northwest HimalayaStable precipitation during 1650s–1850s CE reveals clear evidence of Little Ice Age (LIA) for the north‐western HimalayaHigh‐magnitude droughts or low precipitation limit the LIA influence before 1650s CE [ABSTRACT FROM AUTHOR]

The rapid advancement in information and communication technology has made e‐learning an alternative learning method for many learners. In the last few years, a huge number of learners around the world have registered in massive open online courses (MOOCs) provided by various online learning platforms. However, MOOC platforms have a vital task for the online course provider to provide enhanced students' learning experiences and satisfaction. In this work, we developed a brain–computer interface for gathering data and detecting a learner's mental situation by observing MOOC videos and electroencephalogram (EEG) devices based on John Sweller's Cognitive Load Theory. The acquired EEG signals are preprocessed with two different normalization methods to scale signals. To validate the introduced framework, the system adopted three machine learning algorithms (random forest using non‐Markovian model, support vector machine, and k‐nearest neighbors) to develop a model with preprocessed training data and test the classifiers to validate their ensemble classifiers' performance. Finally, experimental analysis showed that the random forest classifier with the non‐Markovian approach achieved more than the other two techniques in the form of overall accuracy (99.15%) and F‐measures (99.21%). [ABSTRACT FROM AUTHOR]

Field observations have shown that a substantial portion of peanut leaves abscise in windrows during pod curing, leading to an uneven distribution of leaves and stems when intact residues are spread during harvest. Possible differences in nitrogen (N) mineralization rates between peanut leaf and stem residues may lead to spatial and temporal variability in available N during subsequent crops. The objective of this study was to quantify N mineralization in soil amended with different peanut residue components under simulated conventional and conservation tillage practices. A 252‐day microlysimeter incubation was conducted in which peanut leaves, stems and a 1:1 mixture of leaves:stems from three varieties were incorporated or placed on the soil surface to simulate conventional or conservation tillage, respectively. Soils were periodically leached to assess N mineralization compared with a soil‐only control. Nitrogen mineralization was only affected by residue component. Averaged over variety and residue placement, soil amended with leaves mineralized 10% more N relative to the control or soil containing stems. It was estimated that leaves supplied 25 kg N ha−1 over 252 days at 0–15 cm soil depth, which would likely be insufficient to induce a yield response by a subsequent crop. This study suggests that uneven distribution of peanut leaf and stem residues following harvest causes only minor spatial and temporal variability in available N during subsequent crop growth. These results support the growing body of evidence indicating that peanut residue N contributions to subsequent crops are negligible in the peanut basin of the south‐eastern USA. [ABSTRACT FROM AUTHOR]

A new series of conjugated copolymers ( PBDT-TPD, PBDT-Th- TPD, PBDT-TT-TPD) containing donor-acceptor (D − A) structure electron-rich benzo[1,2- b:4,5- b′]dithiophene ( BDT) units with branched alkyl thiophene side chains and electron-deficient 5-(2-octyl)-4 H-thieno[3,4- c]pyrrole-4,6(5 H)-dione (TPD) units was designed and synthesized. To tune the optical and electrochemical properties of the copolymers, the conjugation length of the copolymers was extended by introducing π-conjugated spacers such as thiophene and thieno[3,2- b]thiophene units. It was observed that PBDT-TPD showed broader absorption spectra in the longer wavelength region and the absorption maximum was red-shifted compared to that of PBDT-Th-TPD, PBDT-TT-TPD. Stokes shifts were calculated to be 52 nm for PBDT-TPD, 153 nm for PBDT-Th-TPD and 146 nm for PBDT-TT-TPD. Further, PBDT-TPD exhibited a deeper highest occupied molecular orbital energy level of −5.53 eV as calculated by cyclic voltammetry. Bulk heterojunction solar cells fabricated using PBDT-TPD as donor material exhibited a power conversion efficiency of 1.92%. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Prior literature provides mixed evidence on managerial risk aversion. Using a sample of 1737 large US firms from 1996 to 2005, we find a negative association between the insider ratio and firm risk. Upon further analysis, we show that firms with a greater insider ratio are also likely to have more conservative CEO compensation and investment policies. Analysis of CEO compensation policies indicates that firms with a greater insider ratio offer lower equity based compensation, lower vega and lower total compensation to their CEOs. Also, firms with a greater insider ratio tend to invest more in tangible assets such as plant and equipment and have lower intangible investments. Consistent with these boards instituting conservative policies, we find that firms with a greater insider ratio perform better when they operate in highly volatile environments. Overall, this study suggests that high-insider boards are more conservative in policy initiation and that such boards are valuable in firms with greater operating uncertainties. [ABSTRACT FROM AUTHOR]

Extranodal marginal zone lymphoma ( EMZL) is a B-cell lymphoma arising from mucosa-associated lymphoid tissue (MALT). The disease characteristics, clinical course and treatment vary considerably based on site of involvement. Because long-term outcome data for EMZL are limited, we sought to describe the clinical details of a large number of patients with EMZL evaluated at the Case Comprehensive Cancer Center over a 12-year period to identify prognostic markers including the impact of site of involvement. We identified 211 cases of EMZL involving the stomach (30%), ocular adnexa (19%), lungs (16%) and intestines (9%). Initial treatment included antibiotics (18%), radiation (21%), rituximab (20%), chemotherapy (3%), rituximab + chemotherapy (7%), surgery (17%) or observation (8%). After a median follow-up of 44·3 months (range 2·2-214·9), median progression-free survival ( PFS) was 68·2 months (95% confidence interval [CI] 54·5-111·3) and median overall survival ( OS) has not been reached. Age >60 years, elevated lactate dehydrogenase level ( LDH), ≥4 lymph node groups involvement, and high follicular lymphoma international prognostic index ( FLIPI) were associated with inferior PFS/ OS. In summary, patients with EMZL have excellent prognosis with median OS in excess of 10 years. Age, elevated LDH, advanced disease, and high FLIPI score are associated with worse outcomes. [ABSTRACT FROM AUTHOR]

4-(4-(4-(4-Aminophenoxy)-2-pentadecylphenoxy)phenoxy)aniline ( APPPA) was synthesized starting from cashew nut shell liquid-derived bisphenol, i.e. 4-(4-hydroxyphenoxy)-3-pentadecylphenol, by nucleophilic substitution reaction with 4-chloronitrobenzene followed by reduction of the formed 4-(4-nitrophenoxy)-1-(4-(4-nitrophenoxy)phenoxy)-2-pentadecylbenzene. Three new polyetherimides containing multiple ether linkages and pendent pentadecyl chains were synthesized by one-step high-temperature solution polycondensation of APPPA in m-cresol with three aromatic dianhydrides, i.e. 3,3′,4,4′-oxydiphthalic anhydride, 4,4′-(hexafluoroisopropylidene)diphthalic anhydride and 3,3′,4,4′-biphenyltetracarboxylic dianhydride. Inherent viscosities and number-average molecular weights of the polyetherimides were in the ranges 0.66-0.70 dL g−1 and 17 100-29 700 g mol−1 (gel permeation chromatography, polystyrene standards), respectively, indicating the formation of reasonably high molecular weight polymers. The polyetherimides were soluble in organic solvents such as chloroform, dichloromethane, tetrahydrofuran, pyridine, m-cresol, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone and dimethylsulfoxide, and could be cast into transparent, flexible and tough films from their solutions in chloroform. The polyetherimides exhibited glass transition temperatures ( Tg) in the range 113-131 °C. The lowering of Tg could be attributed to the combined influence of flexibilizing ether linkages and pentadecyl chains which act as 'packing-disruptive' groups. The temperature at 10% weight loss ( T10), determined from thermogravimetric analysis in nitrogen atmosphere, was in the range 460-470 °C demonstrating good thermal stability. The virtues of solubility and large gap between Tg and T10 mean that the polyetherimides containing pendent pentadecyl chains have possibilities for both solution as well as melt processability. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]