bluuebunny/crossref_metadata_2025_split huggingface dataset:
A density functional theory study of the reactions of furans with substituted alkynes to form oxanorbornadienes and subsequent [4 + 2] and [2 + 2 + 2] addition reactions
Authors: Samba Wisdom Kwaku , Tia Richard , Adei Evans 
Published: August 2021

AbstractThis work investigated theoretically, at the M06/6‐311++G(d,p) level of theory, the Diels–Alder reactions of furan with substituted alkynes to afford oxanorbornadienes and the subsequent [4 + 2] and [2 + 2 + 2] cycloaddition reactions leading to the formation of heterocyclic furans, deltacyclenes, and bicyclic oxanorbornadienes, which have high utility in the chemical and pharmaceutical industries. The results show that in the initial Diels–Alder reactions to afford oxanorbornadiene intermediates, reactions of alkynes bearing electron‐withdrawing substituents have lower activation barriers compared with those with electron‐donating substituents. In the [4 + 2] reactions of the oxanorbornadiene intermediates to form bicyclic oxanorbornadienes, oxanorbornadienes with electron‐donating groups favor addition across the unsubstituted olefinic bond, whereas those with electron‐withdrawing substituents favor addition across the substituted double bond, but in both cases, the exo stereoisomer is favored. The regioselectivity of the reactions are strictly dictated by the nature of substituent on oxanorbornadiene. The retrocleavage step, regardless of the addition sequence and nature of substituents, is the rate‐determining step. For the reactions of substituted oxanorbornadienes with furan along the [4 + 2] cycloaddition and the [2 + 2 + 2] cycloaddition (dimerization) of substituted oxanorbornadienes, we observed a decrease in activation barriers when electron‐withdrawing substituents are involved. The global electrophilicity indices (ω) and maximum electronic charge transfer (ΔNmax) computed for various oxanorbornadiene derivatives considered in this work is consistent with energetic trends and experimental outcomes. Perturbation molecular orbital theory was employed to rationalize the results.
Using DP4+ probability for structure elucidation of sesquiterpenic lactones: The case of (−)‐Istanbulin A
Authors: Colasurdo Diego D. , Arancibia Luz A. , Naspi Mariana L. , Laurella Sergio L. 
Published: August 2021

AbstractTheoretical calculations have become a crucial support for experimental data when it comes to confirming and/or rejecting molecular structure. Quantum calculations have therefore become essential for other research fields, such as total synthesis of natural products or the study of their mechanisms of action, among others. In this communication, four different parameters are used for the confirmation of the structure of (−)‐Istanbulin A, testing the experimental NMR data against eight possible stereoisomers. (−)‐Istanbulin A is a natural product (an eremophilane) extracted from the aerial parts of Senecio filaginoides DC (an endemic plant from Patagonia Argentina) that has proven successful as antibacterial and antifungal agent. The structures of the eight possible stereoisomers were optimized by means of DFT calculations (B3LYP/6‐311+G[d,p] in vacuum), and then their isotropic shielding tensors were obtained using GIAO‐B3LYP/6‐31+G(d,p) method in chloroform. Isotropic shielding values of 1H and 13C were converted into chemical shifts by subtraction of TMS analog values. The eight sets of calculated data were compared with the spectroscopic chemical shifts in order to find the most probable structure. This was made by means of the parameters R2 (correlation coefficient), MAE (mean absolute error), CMAE (corrected mean absolute error), and DP4+ probability. While R2, MAE, and CMAE afford uncertain results which do not permit confirmation of the molecular structure, DP4+ predicts the isomer of configuration (4S,5R,8R,10S) with more than 99% probability. These results open the possibility of applying DP4+ method for confirming the relative configuration of other istanbulins (and probably other eremophilanes).
Characterization of polymeric surfaces and interfaces using time‐of‐flight secondary ion mass spectrometry
Authors: Mei Hao , Laws Travis S. , Terlier Tanguy , Verduzco Rafael , Stein Gila E. 
Published: August 2021

AbstractTime‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) is used for chemical analysis of surfaces. ToF‐SIMS is a powerful tool for polymer science because it detects a broad mass range with good mass resolution, thereby distinguishing between polymers that have similar elemental compositions and/or the same types of functional groups. Chemical labeling techniques that enhance contrast, such as deuterating or staining one constituent, are generally unnecessary. ToF‐SIMS can generate both two‐dimensional images and three‐dimensional depth profiles, where each pixel in an image is associated with a complete mass spectrum. This Review begins by introducing the principles of ToF‐SIMS measurements, including instrumentation, modes of operation, strategies for data analysis, and strengths/limitations when characterizing polymer surfaces. The sections that follow describe applications in polymer science that benefit from characterization by ToF‐SIMS, including thin films and coatings, polymer blends, composites, and electronic materials. The examples selected for discussion showcase the three standard modes of operation (spectral analysis, imaging, and depth profiling) and highlight practical considerations that relate to experimental design and data processing. We conclude with brief comments about broader opportunities for ToF‐SIMS in polymer science.
Barriers to cancer care for people with significant mental health difficulties: What healthcare staff say?
Authors: D’Alton Paul , O’Meara Rachel , Langford Seán , McDonnell Zoe , Nuzum Ann , Murthy Varsha Eswara , Craddock Fiona , Cogley Clodagh , McCormack Derval 
Published: August 2021

AbstractObjectivesDespite similar rates in cancer morbidity, patients with comorbid significant mental health difficulties (SMHD) experience higher mortality rates. This population has largely been neglected in cancer care research. Little is known about how to improve cancer outcomes for patients with SMHD. The aim of this research is to explore the views of healthcare professionals concerning the provision of cancer care to individuals with SMHD in an Irish context.MethodsSemi‐structured interviews were conducted with healthcare professionals (n = 28) providing care to people with SMHD and cancer. This included oncology and psychiatry consultants (n = 10); clinical nurse specialists (n = 8); clinical psychologists (n = 6); and medical social workers (n = 4). Data were analysed using thematic analysis.ResultsFour overarching themes were generated from the data highlighting the challenges associated with healthcare provision for this cohort. The themes were: Fragmentation of Care, Healthcare Providers' Understanding of SMHD, Complex Nature of Presentation, and Specialised Care Needs.ConclusionsThe findings contribute to advancing our understanding of cancer care provision for patients with SMHD. They identify important barriers and facilitators to cancer care provision for this population from the perspective of healthcare professionals in Ireland. These findings will help to shape future research and contribute to improving the quality‐of‐care for people with SMHD and cancer.
Are family relationships associated with family conflict in advanced cancer patients?
Authors: Hamano Jun , Masukawa Kento , Tsuneto Satoru , Shima Yasuo , Morita Tatsuya , Kizawa Yoshiyuki , Miyashita Mitsunori 
Published: August 2021

AbstractObjectivesFamily conflict during end‐of‐life care is an important issue for advanced cancer patients and their families, although studies are lacking. We investigated the association between family relationships and family conflict in advanced cancer patients.MethodsThis study was a secondary analysis of a nationwide multicenter questionnaire survey targeting the bereaved family members of cancer patients who died in palliative care units, general wards, or at home to evaluate the quality of end‐of‐life care in Japan.ResultsA total of 1084 questionnaires (63.0%) were returned and we analyzed a total of 908 responses. In total, 38.0% of family members reported at least one family conflict during end‐of‐life care, and the most frequent family conflict was “about certain family members not pulling their weight” (23.5%). Multivariate linear analysis revealed family members who asserted their opinions (p < 0.001), family assessment device score (p < 0.001), worries about family finances during cancer treatment (p < 0.001), family members contacted after illness were helpful (p = 0.003), female patients (p = 0.03), and family with family relationship index ≤7 (p = 0.04) were positively associated with the outcome‐family conflict (OFC) score. Proxy decision maker was selected by the patient (p = 0.003), people listened to families' worries or problems (p = 0.003), physician gave sufficient explanation (p = 0.003), living will before their illness (p = 0.038) and female bereaved family members (p = 0.046) were negatively associated with the OFC score.ConclusionsIt may be important for health care providers to actively assess the possibility of family conflicts according to family relationships, such as a proxy decision maker having been selected by the patient.
Risk factors for suicide mortality and cancer‐specific mortality among patients with gastric adenocarcinoma: A SEER based study
Authors: Elshanbary Alaa Ahmed , Zaazouee Mohamed Sayed , Hasan Sara Mohamed , Abdel‐Aziz Walid 
Published: August 2021

AbstractObjectiveThis study aims to investigate the risk factors for suicide in patients with gastric adenocarcinoma (GAC) to recognize patients at higher risk who require special mental health care.MethodsPatients' data were collected from the Surveillance, Epidemiology, and End Results database from 1975 to 2016. The relationships among categorical variables were assessed using Person's chi‐square test. Standardized mortality ratio was used to compare ratios of suicide and other causes of death between the US population and adenocarcinoma patients. Cox regression and Kaplan‐Meier were used for multivariate and univariate analyses. The probability of suicide was assessed using the binary regression analysis. All analyses were conducted using SPSS software.ResultsAmong 59,580 patients included in this study, 86 died due to suicide. The mean survival months was higher in patients <50 years (81.759) than in patients ≥50 years (42.961), and in females (49.116) than in males (44.591). The multivariate analysis showed a higher suicide mortality risk in divorced patients (HR = 2.461; 95% CI [1.015, 5.966], p = 0.046), patients not recommended for surgery (HR = 1.997; 95% CI [1.08, 3.694], p = 0.027) and patients with distant stage of the disease (HR = 2.68; 95% CI [1.395, 5.147], p = 0.003). Females had a lower suicide mortality risk (HR = 0.124; 95% CI [0.045, 0.314], p < 0.001).ConclusionGAS predisposes to suicide. The risk is higher in patients who are males, divorced, not recommended for surgery, or have a distant spread of the disease.
Mediastinal and neck follicular dendritic cell sarcoma treated with definitive radiation therapy using the volumetric modulated arc therapy technique: a case report
Authors: Calcuttawala Adnan , Deshmane Nilesh , Pol Jaydeep , Desai Sharad 
Published: August 2021

AbstractFollicular dendritic cell sarcoma (FDCS) is a rare malignancy that affects the nodal and extranodal tissues. The mediastinum is a rare site for this tumor, with few published reports and series. Although surgery is the mainstay of treatment for this disease entity, in this report we present a case of mediastinal FDCS treated with definitive radiation therapy (RT) with a near‐total radiological response. A 28‐year‐old woman presented with chest tightness and neck swelling. Radiological findings were suggestive of a conglomerated nodal mass involving the mediastinum and extending superiorly into the anterior neck. Biopsy results led to a diagnosis of FDCS. The tumor was deemed unresectable, and definitive RT was planned as the treatment. The patient was treated with volumetric modulated arc therapy to a total dose of 54 Gy in 30 fractions over 6 weeks. Her symptoms had completely resolved at the first follow‐up visit, 3 months after RT completion, with a near‐total radiological response on a contrast‐enhanced computed tomography scan. Although surgery is the standard of care in FDCS, based on the favorable response of FDCS to RT, as in this case, the role of definitive RT needs to be studied in more patients to determine its efficacy in long‐term tumor control as an alternative to surgery.
Area‐population control of fungus‐growing termite,Odontotermes formosanus, using hexaflumuron durable baits
Authors: Chiu Chun‐I , Chuang Ya‐Hui , Liang Wei‐Ren , Yeh Hsin‐Ting , Yang Hsiao‐Ying , Tsai Ming‐Jer , Spomer Neil A , Li Hou‐Feng 
Published: August 2021

AbstractBACKGROUNDFungus‐growing termites (Termitidae: Macrotermitinae) are common forest and agriculture pests. To evaluate the efficacy of termite baiting in suppressing field population of fungus‐growing termites, a durable termite bait with hexaflumuron was evenly installed in a one‐hectare forest area dominated by a fungus‐growing termite,Odontotermes formosanus(Shiraki). Monthly monitoring of termite foraging activity on baits and wood stakes was conducted for 4 years to quantify efficacy of baits. To examine whether the hexaflumuron led to colony death, pesticides in fungus gardens of active and deceased nests were quantified using a LC‐QTOF/MS.RESULTSAfter baiting, 50% and 90% of baits were fed upon 10 and 24 months, respectively. After 2 years of baiting, the monthly number of wood stakes occupied by termites was reduced from 34.7 ± 1.8 to 17.6 ± 2.5 (−49.1%), and the number of wood stakes consumed was reduced from 17.7 ± 0.8 to 13.3 ± 1.2 (−25.7%). Hexaflumuron was detected in deceased colonies, including five of six fungus gardens and the fungal tissue ofXyleriagrown on fungus gardens, with a concentration of 0.31–20.11 mg kg−1dry weight.CONCLUSIONThis study demonstrated that durable hexaflumuron baits consumed by fungus‐growing termites were further incorporated into fungus gardens, resulted in colony elimination and negative area‐population effects, supporting that durable hexaflumuron baits are effective in suppressing field populations of fungus‐growing termites. © 2021 Society of Chemical Industry.
Long‐term effect of sugarcane residue management and chemical fertilization on soil physical properties in South Africa
Authors: Deeb Maha , Grimaldi Michel , Aroui Hanane , Mthimkhulu Sandile , Van Antwerpen Rianto , Podwojewski Pascal 
Published: August 2021

AbstractSugarcane (Saccharum officinarum L.), an intensive, long‐term, monoculture, economical crop in South Africa, is known to degrade soil characteristics. Soil structure, a key indicator of soil health and biomass production potential, is manageable by agricultural practices. This study aims to evaluate the effect of crop residue management practices (mulching, burning with residues scattered or removed) and mineral fertilization (with or without) on soil structure by analyzing soil shrinkage curves (SSCs) and other soil physical and chemical properties in a long‐term sugarcane trial established in 1939. The SSC provides descriptive structural soil data by differentiating and characterizing two pore systems (plasma and structural pores). By analyzing the SSC of 24 plots (four replicates each treatment), residue management and fertilization practices were found to have statistically and physically significant effects on hydrostructural variables. Partial redundancy analysis showed that residue management practices had a slightly higher effect (19% of total variance) on hydrostructural variables compared with fertilization (12%). The main hydrostructural variables representing the management effect were total soil shrinkage, specific volume, and swelling capacity of the plasma, which were higher in mulched and/or unfertilized plots, indicating that soil was less compact, and shrinkage was more intense, including at the plasma level. The stronger structural dynamics and aggregate stability of the soil were explained by the behavior of the primary aggregates (peds), which were more porous and reactive during the drying process. This study highlights the importance of mulching and limited fertilization to maintain soil structure in the long term while still ensuring yield production.
Gold mining in Ghana and the UN Sustainable Development Goals: Exploring community perspectives on social and environmental injustices
Authors: Essah Marcellinus 
Published: August 2021

AbstractAlthough gold mining multinational or transnational companies continue to profit from their activities in resource endowed developing countries, the gap between company profits and social and environmental justice in these resource rich developing countries is a subject of intense debate. This debate is especially heightened when the gap is examined in the context of the United Nations Sustainable Development Goals (SDGs). This paper employs the Environmental Justice concept to assess the activities of the Goldfields Damang mining company in Ghana vis‐à‐vis the UN Sustainable Development Goals. Drawing on primary data from semi‐structured interviews (n = 22) and secondary sources, the paper finds that the negative impacts of gold mining do not conform with the UN Sustainable Development Goals, especially goals 2, 6, 14 and 15. The study makes two recommendations: First, policies on land tenure and the Mineral and Mining Act need revisions to incorporate more rights for indigenous people; second, existing structures and legislation that spells out compensation and land dispossession practices must be revised thoroughly to align with the UN sustainable development goals. The paper concludes by considering the theoretical and policy implications of the findings for strengthening mining laws and policies in Ghana.
Positive interventions for stress‐related difficulties: A systematic review of randomized and non‐randomized trials
Authors: Ferrandez Sébastien , Soubelet Andrea , Vankenhove Louna 
Published: August 2021

AbstractThe effectiveness of positive psychology interventions in the treatment of stress‐related difficulties have not been well established. To estimate the effectiveness of positive psychology interventions on the reduction of stress‐related symptoms, a systematic review using PubMed, Scopus, Wiley, Psychinfo, Cochrane and Sage databases with no limitation of date of publication was conducted. We identified additional studies by searching positive psychology reviews and academic books. Only studies trying positive interventions that included measures of anxiety, stress, or posttraumatic stress disorder symptoms were reviewed. We extracted data using predefined data fields and study quality was assessed with the National Institutes of Health study quality assessment tools. Twenty‐nine records were included in this study: 23 controlled trials and six pre‐post studies. Every study showed significant improvement in at least one dimension. Several studies reported improvements in well‐being as well. This review shows promising results of positive psychology interventions as a treatment for stress‐related difficulties. However, important methodological biases and strong heterogeneity among the studies highlight the need for replication and better validation of positive psychology interventions.
A High Rate and Stable Hybrid Li/Na‐Ion Battery Based on a Hydrated Molten Inorganic Salt Electrolyte
Authors: Wang Zhengying , Xu Yue , Peng Jian , Ou Mingyang , Wei Peng , Fang Chun , Li Qing , Huang Jiang , Han Jiantao , Huang Yunhui 
Published: August 2021

AbstractTaking into the consideration safety, environmental impact, and economic issue, the construction of aqueous batteries based on aqueous electrolyte has become an indispensable technical option for large‐scale electrical energy storage. The narrow electrochemical window is the main problem of conventional aqueous electrolyte. Here, an economical room‐temperature inorganic hydrated molten salt (RTMS) electrolyte with a large electrochemical stability window of 3.1 V is proposed. Compared with organic fluorinated molten salts, RTMS is composed of lithium nitrate hydrate and sodium nitrate with much lower cost. Based on the RTMS electrolyte, a hybrid Li/Na‐ion full battery is fabricated from cobalt hexacyanoferrate cathode (NaCoHCF) and perylene‐3,4,9,10‐tetracarboxylic dianhydride (PTCDA) anode. The full cell with the RTMS electrolyte exhibits a fantastic performance with high capacity of 139 mAh g−1 at 1 C, 90 mAh g−1 at 20 C, and capacity retention of 94.7% over 500 cycles at 3 C. The excellent performances are contributed to the unique properties of RTMS with a large electrochemical window, solvated H2O free and high mobility of Li+, which exhibits excellent Li‐ions insertion and extraction capacity of NaCoHCF. This RTMS cell provides a new economic choice for large‐scale energy storage.
Revealing Nanoscale Confinement Effects on Hyperbolic Phonon Polaritons with an Electron Beam
Authors: Konečná Andrea , Li Jiahan , Edgar James H. , García de Abajo F. Javier , Hachtel Jordan A. 
Published: August 2021

AbstractHyperbolic phonon polaritons (HPhPs) in hexagonal boron nitride (hBN) enable the direct manipulation of mid‐infrared light at nanometer scales, many orders of magnitude below the free‐space light wavelength. High‐resolution monochromated electron energy‐loss spectroscopy (EELS) facilitates measurement of excitations with energies extending into the mid‐infrared while maintaining nanoscale spatial resolution, making it ideal for detecting HPhPs. The electron beam is a precise source and probe of HPhPs, which allows the observation of nanoscale confinement in HPhP structures and directly extract hBN polariton dispersions for both modes in the bulk of the flake and modes along the edge. The measurements reveal technologically important nontrivial phenomena, such as localized polaritons induced by environmental heterogeneity, enhanced and suppressed excitation due to 2D interference, and strong modification of high‐momenta excitations such as edge‐confined polaritons by nanoscale heterogeneity on edge boundaries. The work opens exciting prospects for the design of real‐world optical mid‐infrared devices based on hyperbolic polaritons.