bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pleistocene environments, climate, and human activity in Britain during Marine Isotope Stage 7: insights from Oak Tree Fields, Cerney Wick, Gloucestershire
Authors: Hogue Joshua T. , Wilkinson Keith N. , Allison Enid , Hill Thomas , Knul Monika V. , Law Matthew , Perez‐Fernandez Marta , Russ Hannah , Schreve Danielle , Sherriff Jennifer E. , Toms Philip , Young Daniel , Westcott‐Wilkins Lisa , Wilkins Brendon 
Published: March 2023

ABSTRACTInvestigations at Oak Tree Fields, Cerney Wick, Gloucestershire, in western England have revealed a sequence of fluvial deposits dating from Marine Oxygen Isotope Stage (MIS) 7 to 5. At the base of the sequence, a series of gravel and sand facies were deposited, initially as part of a meandering river. Reductions in flow energy of the latter and avulsion led to the development of short‐lived channels and episodic backwater environments, the deposits of which are recorded as Facies Associations 1–3. Poorly sorted, probably colluvial deposits formed beyond the limit of the channel (Facies Association 4). Mollusca, Coleoptera, plant macrofossils, pollen and vertebrates recovered from the channel facies indicate broadly similar climatic conditions throughout accretion. Temperature ranges derived from mutual climatic range analysis of the Coleoptera almost completely overlap with those of Cerney Wick at the present day, albeit that winters may have been cooler when the channel was active. Further, the floral and faunal data suggest that the meandering river flowed through an open grassland environment, the latter heavily grazed by large vertebrates, most notably mammoth. Most of the botanical and faunal remains, together with four optically stimulated luminescence (OSL) age estimates ranging from 225 ± 23 to 187 ± 19 ka, suggest correlation of the channel deposits with MIS 7. The basal deposits (Facies Association 1) yielded the majority of vertebrate remains and all the lithic artefacts, most of which seem likely to have travelled only a short distance. Although only a few artefacts were recovered, they add to the relatively limited evidence of human activity from the upper Thames. The channel deposits are overlain by sheet gravels (Facies Association 5) which are attributed to the Northmoor Member of the Upper Thames Formation. These were likely to have been deposited as bedload in a braided stream environment, while two OSL age estimates of 129 ± 14 and 112 ± 11 ka suggest accumulation during MIS 5.
Efficient strategies for preparative separation of iridoid glycosides and flavonoid glycosides from Hedyotis diffusa
Authors: Dai Yingping , Zhang Hongzhi , Wang Xinhe , Chen Yanchun , Fu Qing , Jin Yu , Liang Xinmiao 
Published: March 2023

Efficient strategies for the preparative separation of iridoid glycosides and flavonoid glycosides from Hedyotis diffusa using preparative high‐performance liquid chromatography combined with appropriate pretreatment technologies were developed. Four fractions (Fr.1‐1, Fr.1‐2, Fr.1‐3, and Fr.2‐1) were firstly isolated from the crude extract of Hedyotis diffusa by column chromatography with C18, resin, and silica gel materials, respectively. Then, corresponding separation strategies were developed according to the polarity and chemical constituents. High‐polar compounds of Fr.1‐1 were purified by hydrophilic reversed‐phase liquid chromatography and hydrophilic interaction liquid chromatography mode. The combination of C18 and phenyl columns realized the complementary separation of iridoid glycosides in Fr.1‐2. Meanwhile, the improved selectivity caused by the change of organic solvent in the mobile phase was utilized to realize the purification of flavonoid glycosides in Fr.1‐3 and Fr. 2‐1. Finally, 27 compounds (purity > 95%) mainly involving nine iridoid glycosides and five flavonoid glycosides were obtained. A complete strategy was established for the separation of a complex sample with a wide polarity range, to jointly solve the problems of enrichment of target components and separation of structural analogs.
Fidelity of implementing a competency‐based nursing programme during the COVID‐19 pandemic: A case study
Authors: Shawa Mirriam , Masava Beloved , Mutimbe Pritchard , Nyoni Tawanda , Mokhele Khantse , Shale Mapoea , Mukurunge Eva , Nyoni Champion 
Published: March 2023

AbstractAimThe study describes the fidelity of implementing a competency‐based nursing education (CBNE) programme during the COVID‐19 pandemic in a low‐resource setting.DesignA descriptive case study research design integrating mixed methods underpinned by the fidelity of implementation framework was applied to assess teaching, learning and assessment during the COVID‐19 pandemic.MethodsA survey, focus group and document analysis were applied to collect data from 16 educators, 128 students and eight administrators of a nursing education institution and accessing institutional documents. Data were analysed through descriptive statistics and deductive content analysis and packaging the outcome of the study according to the five elements related to the fidelity of implementation framework.ResultsThe fidelity of implementing the CBNE programme was satisfactorily maintained as described in the fidelity of implementation framework. However, sequenced progression and programmatic assessments were not aligned with a CBNE programme within the context of the COVID‐19 pandemic.Patient or Public ContributionThis paper proposes strategies to enhance the fidelity of implementing competency‐based education during educational disruptions.
Lignin‐based covalent adaptable network resins for digital light projection 3D printing
Authors: Johnson Rebecca M. , Cortés‐Guzmán Karen P. , Perera Sachini D. , Parikh Ankit R. , Ganesh Vijayalakshmi , Voit Walter E. , Smaldone Ronald A. 
Published: March 2023

Abstract3D printing is a low cost, customizable, and fast‐growing technology with the potential to revolutionize plastic manufacturing. Vat photopolymerization 3D printing technologies stand out for their high resolution, however, the resulting printed materials are made from petroleum feedstocks and are covalently crosslinked which renders them unrecyclable. Here, resin formulations with 70 wt% bio‐based content and dynamic functionality are synthesized and printed using lignin, vanillin, and soybean oil components. These printed polymers can undergo dynamic transesterification due to the methacrylated lignin (LMA) to allow for self‐healing capabilities; therefore, potentially increasing the materials lifetimes compared to traditional thermoset materials, offsetting the use of traditional petroleum‐based resins, and lowering their environmental impact. The LMA also provides the thermosets with better mechanical performance and thermal stability in comparison to the controls. Additionally, compatibility with 3D printing technologies improves the competitiveness of biobased plastics with conventional materials.
New structures reveal flexible dynamics between the subdomains of peptidylglycine monooxygenase. Implications for an open to closed mechanism
Authors: Arias Renee J. , Welch Evan F. , Blackburn Ninian J. 
Published: March 2023

AbstractPeptidylglycine monooxygenase (PHM) is essential for the biosynthesis of many neuroendocrine peptides via a copper‐dependent hydroxylation of a glycine‐extended pro‐peptide. The “canonical” mechanism requires the transfer of two electrons from one mononuclear copper (CuH, H‐site) to a second mononuclear copper (CuM, M‐site) which is the site of oxygen binding and catalysis. In most crystal structures the copper centers are separated by 11 Å of disordered solvent, but recent work has established that a PHM variant H108A forms a closed conformer in the presence of citrate with a reduced Cu–Cu site separation of ~4 Å. Here we report three new PHM structures where the H and M sites are separated by a longer distance of ~14 Å. Variation in Cu–Cu distance is the result of a rotation of the M subdomain about a hinge point centered on the pro199‐leu200‐ile201 triad which forms the linker between subdomains. The energetic cost of domain dynamics is likely small enough to allow free rotation of the subdomains relative to each other, adding credence to recent suggestions that an open‐to‐closed transition to form a binuclear oxygen binding intermediate is an essential element of catalysis. This inference would explain many experimental observations that are inconsistent with the current canonical mechanism including substrate‐induced oxygen activation and isotope scrambling during the peroxide shunt.
Chrysophanol alleviates acute lung injury caused by Klebsiella pneumoniae infection by inhibiting pro‐inflammatory cytokine production
Authors: Jiang Fei , Jiang Jiebang , He Wenping , Dong Guokai , Xu Nana , Meng Li , Zhao Yunyun , Wang Meng , Tan Shirui , Shi Yongping , Li Rongpeng 
Published: March 2023

AbstractAcute lung injury (ALI) caused by acute bacterial infection remains a common life‐threatening lung disease. An increased inflammatory response is the basis for the occurrence and development of ALI. Most antibiotics can only reduce the bacterial load but do not protect from lung damage because of an excessive immune response. Chrysophanol (chrysophanic acid, Chr), as a natural anthraquinone extracted from Rheum palmatum L., has various biological functions, including anti‐inflammatory, anti‐cancer activities, and ameliorative effects on cardiovascular diseases. Considering these properties, we investigated the effect of Chr in Klebsiella pneumoniae (KP)‐induced ALI mice and its potential mechanism. Our results showed that Chr had protective effects against KP‐infected mice, including increased survival rate, decreased bacterial burden, reduced recruitment of immune cells, and reduced reactive oxygen species level of lung macrophages. Chr reduced the expression of inflammatory cytokines by inhibiting the toll‐like receptor 4/nuclear factor kappa‐B (TLR4/NF‐κB) signaling pathway and inflammasome activation and strengthening autophagy. Overactivation of the TLR4/NF‐κB signaling pathway by the activator Neoseptin 3 led to Chr losing control of inflammatory cytokines in cells, resulting in increased cell death. Similarly, overactivation of the c‐Jun N‐terminal kinase signaling pathway using the activator anisomycin resulted in Chr losing its inhibitory effect on NOD‐like receptor thermal protein domain associated protein 3 (NFRP3) inflammasome activation, and cell viability was reduced. In addition, autophagy was blocked by siBeclin1, so Chr could not reduce inflammatory factors, and cell viability was markedly inhibited. Collectively, this work unravels the molecular mechanism underpinning Chr‐alleviated ALI via inhibiting pro‐inflammatory cytokines. Thus, Chr is a potential therapeutic agent for KP‐induced ALI.
Current state and research directions for disposable versus reusable packaging: A systematic literature review of comparative studies
Authors: Pålsson Henrik , Olsson John 
Published: March 2023

AbstractThe use of disposable and reusable packaging is a hot topic in policy and practice, but different studies have come to different conclusions on when each packaging type is the more sustainable alternative. The purpose of this paper is to map and review scientific literature that compares disposable and reusable packaging for food, beverages and e‐commerce from a sustainability perspective. The methodology is a systematic literature review, which identifies 91 scientific papers. The paper describes and analyses the origin, characteristics and state of current knowledge and then proposes future research directions within five areas. It identifies and presents what is known in literature to achieve environmental and social sustainability, as well as circularity for disposable compared to reusable packaging. The review shows that the literature is to great extent qualitative, often studying individual products in a specific context. European studies dominate the current literature, and many of them revolve around a few types of products and packaging. Slightly under half of the studies use the life cycle assessment (LCA) methodology. The review of these studies provides some indicative suggestions for when disposable and reusable packaging is environmentally preferable, but the number of LCA studies is too limited, and their content too fragmented to draw general conclusions about this. Overall, the review of 91 articles shows a great need for continued research that compares the environmental efficiency of disposable and reusable packaging. It also highlights the necessity for more knowledge to be able to clearly state under what conditions and in what contexts disposable and reusable packaging are the most sustainable options.
Reactivation of herpesviruses during COVID‐19: A systematic review and meta‐analysis
Authors: Shafiee Arman , Teymouri Athar Mohammad Mobin , Amini Mohammad Javad , Hajishah Hamed , Siahvoshi Sepehr , Jalali Mehrsa , Jahanbakhshi Bahar , Mozhgani Sayed‐Hamidreza 
Published: March 2023

AbstractTo provide a comprehensive systematic review and meta‐analysis regarding the cumulative incidence (incidence proportion) of human herpesvirus (HHV) reactivation among patients with coronavirus disease 2019 (COVID‐19), we searched PubMed/MEDLINE, Web of Science, and EMBASE up to 25 September 2022, with no language restrictions. All interventional and observational studies enrolling patients with confirmed COVID‐19 and providing data regarding HHV reactivation were included. The random‐effects model was used in the meta‐analyses. We included information from 32 studies. HHV reactivation was considered a positive polymerase chain reaction result taken at the time of COVID‐19 infection. Most of the included patients were severe COVID‐19 cases. The pooled cumulative incidence estimate was 38% (95% Confidence Intervals [CI], 28%–50%, I2 = 86%) for herpes simplex virus (HSV), 19% (95% CI, 13%–28%, I2 = 87%) for cytomegalovirus (CMV), 45% (95% CI, 28%–63%, I2 = 96%) for Epstein‐Barr virus (EBV), 18% (95% CI, 8%–35%) for human herpesvirus 6 (HHV‐6), 44% (95% CI, 32%–56%) for human herpesvirus 7 (HHV‐7), and 19% (95% CI, 14%–26%) for human herpesvirus 8 (HHV‐8). There was no evidence of funnel plot asymmetry based on visual inspection and Egger's regression test for the results of HSV (p = 0.84), CMV (p = 0.82), and EBV (p = 0.27) reactivation. In conclusion, the identification of HHV reactivation in severe COVID‐19 patients is helpful in the management of patients as well as the prevention of complications. Further research is required to elucidate the interaction between HHVs and COVID‐19. Systematic review registration: PROSPERO CRD42022321973.
Anticancer Structure‐activity Relationships and Potential Target Exploration of the Natural Product Gypsogenin
Authors: Sun Kang‐Ping , Zhao Ting‐Ting , Liu Lei , Mu Xiao‐Dong , Sun Jing‐Yong 
Published: March 2023

AbstractCombined with molecular docking and molecular dynamic (MD) simulation, the derivative directions and structure‐activity relationships of the compounds were initially explored. Nineteen gypsogenin derivatives were synthesized and screened for cytotoxic activities. Their structures were established using IR, 1H NMR, 13C NMR, and LC–MS spectroscopic data. In the CCK‐8 assays, most of the compounds displayed good cytotoxicity in the low μΜ range for several human tumor cell lines (A549, MCF‐7 and LOVO). The bioassay test suggested that most of these derivatives showed antitumor activities. In particular, some compounds posed moderate antitumor activity. They may be related to start the process of apoptosis and lead to cell death.
Insight into Electrochemical Performance of Nitrogen‐Doped Carbon/NiCo‐Alloy Active Nanocomposites
Authors: Wang Kuaibing , Chen Changyun , Li Yihao , Hong Ye , Wu Hua , Zhang Cheng , Zhang Qichun 
Published: March 2023

AbstractNanocomposites containing Ni or Co or NiCo alloy and nitrogen‐doped carbon with diverse ratios have been prepared and utilized as active elements in supercapacitors. The atomic contents of nitrogen, nickel, and cobalt have been adjusted by the supplement amount of Ni and Co salts. In virtue of the excellent surface groups and rich redox active sites, the NC/NiCo active materials exhibit superior electrochemical charge‐storage performances. Among these as‐prepared active electrode materials, the NC/NiCo1/1 electrode performs better than other bimetallic/carbon electrodes and pristine metal/carbon electrodes. Several characterization methods, kinetic analyses, and nitrogen‐supplement strategies determine the specific reason for this phenomenon. As a result, the better performance can be ascribed to a combination of factors including the high surface area and nitrogen content, proper Co/Ni ratio, and relatively low average pore size. The NC/NiCo electrode delivers a maximum capacity of 300.5 C g−1 and superior capacity retention of 92.30% after 3000 unceasing charge‐discharge cycles. After assembling it into the battery‐supercapacitor hybrid device, a high energy density of 26.6 Wh kg−1 (at 412 W kg−1) is achieved, comparable to the recent reports. Furthermore, this device can also power four light‐emitting‐diode (LED) demos, suggesting the potential practicability of these N‐doped carbon compositing with bimetallic materials.
Role of NF‐κB signaling pathway in hexavalent chromium‐induced hepatotoxicity
Authors: Shen Jiayuan , Kom Merveille Chancelle , Huang Huarong , Fu Guoquan , Xie Yixia , Gao Yue , Tang Yaxin , Yan Junyan , Jin Lifang 
Published: March 2023

AbstractHexavalent chromium Cr (VI) is a primary human carcinogen with damaging toxic effects on multiple organs. Cr (VI) exposure can induce hepatotoxicity through oxidative stress, but its exact mechanism of action was still unclear. In our study, a model of acute Cr (VI) induced liver injury was established by exposing mice to different concentrations (0, 40, 80, and 160 mg/kg) of Cr (VI); RNA‐seq was used to characterize changes in liver tissue transcriptome of C57BL/6 mice after exposing to 160 mg/kg Bw of Cr (VI). Changes in liver tissue structures, proteins, and genes were observed by hematoxylin and eosin (H&E), western blot, immunohistochemistry and RT‐PCR. After Cr (VI) exposure, abnormal liver tissue structure, hepatocyte injury, and hepatic inflammatory response were observed in mice in a dose‐dependent manner. RNA‐seq transcriptome results indicated that oxidative stress, apoptosis, and inflammatory response pathways were increased after Cr (VI) exposure; KEGG pathway analysis found that activation of NF‐κB signaling pathway was significantly upregulated. Consistent with the RNA‐seq results, immunohistochemistry showed that Cr (VI) exposure resulted in infiltrating of Kupffer cells and neutrophils, increasing expression of inflammatory factors (TNF‐α, IL‐6, IL‐1β), and activating of NF‐κB signaling pathways (p‐IKKα/β and p‐p65). However, ROS inhibitor, N‐acetyl‐L‐cysteine (NAC), could reduce infiltration of Kupffer cells and neutrophils and expression of inflammatory factors. Besides, NAC could inhibit NF‐κB signaling pathway activation, and alleviate Cr (VI)‐induced liver tissue damage. Our findings strongly suggested that inhibition of ROS by NAC might help in the development of new strategies for Cr (VI)‐associated liver fibrosis. Our findings revealed for the first time that Cr (VI) induced liver tissue damage through the inflammatory response mediated by the NF‐κB signaling pathway, and inhibition of ROS by NAC might help in the development of new strategies for Cr (VI)‐associated hepatotoxicity.
Opportunities in and Approaches to the Study of Angolan Ecology
Authors: Huntley Brian John 
Published: March 2023

AbstractThis Chapter presents an African perspective to the interdisciplinary science of ecology. It explains why an ecological understanding of the structure and functioning of ecosystems is critical to achieving the sustainable use of the biosphere. It describes how the spatial and temporal scales of pattern reflect biological organisation from individuals to communities to ecoregions. It introduces the student to the scientific method, and outlines the structure of the book, guiding its use in the phased steps of the learning process. Its key message is that the ecological whole is greater than the sum of its parts.
The Arid Savanna Biome
Authors: Huntley Brian John 
Published: March 2023

AbstractThe Arid Savanna Biome of Angola (and Africa) is home to the richest wildlife diversities and abundances of the continent. This Chapter describes the features that characterise the biome – low and unpredictable rainfall, generally low primary production, infrequent but occasionally intense fires, occupying the young, moderate to high nutrient soils of the hot lowlands and river valleys of the western coastal belt and south of the country. The three ecoregions of this biome occur at from sea level to 1000 m above sea level, where rainfall ranges from 250-650 mm per year. Colophospermum mopane dominates and characterises the largest ecoregion of the Arid Savanna Biome in Angola (and across southern Africa), has a low diversity of plant species, but is rich in mammal and bird species. The factors that determine the distribution of this generally monospecific woodland have been subject to detailed research and the results are described. The other two Arid Savanna Biome ecoregions are dominated by Acacia species, with a prominence of baobabs Adansonia digitata. The Arid Savanna Biome supported the highest biomasses and diversities of indigenous mammal species in Angola until their near annihilation during the civil war and replacement by domestic livestock in recent decades.
The Mangrove Biome
Authors: Huntley Brian John 
Published: March 2023

AbstractThe cold Benguela Current passing along Angola’s Atlantic Ocean coast accounts for its mangrove communities lying 20° latitude north of those of the Indian Ocean Coast of Africa, bathed by the warm Mozambique Current. This chapter draws on the limited literature available on Angola’s mangrove forests and seagrass meadows that constitute its Mangrove Biome. Comprising only five of the world’s 55 mangrove species, and two of the world’s 70 species of seagrasses, Angola’s mangrove communities cover a very limited area compared with other tropical countries. This is due to Angola’s steeply shelving coastline, with small lagoons and mudflats at the mouths of its rivers. However, they provide excellent opportunities for the study of the complex adaptations of plants to regular changes in water salinity and to growth in waterlogged, anoxic soil. The adaptations include stilt roots, with specialised absorptive pores, roots containing porous aerenchyma tissue for oxygen transfer, and reproductive propagules that develop into seedlings while still attached to the tree. The mudflats of coastal lagoons support two species of seagrass (highly specialised angiosperms that are permanently submerged). Seagrass meadows provide habitat for a wide diversity of marine animals, while mangrove forests shelter several crocodile and primate species.