bluuebunny/crossref_metadata_2025 huggingface dataset:
Archaeologies of Climate Change: Perceptions and Prospects
Authors: Britton Kate , Hillerdal Charlotta
Published: November 2020

Climate change is the biggest challenge facing humanity today, and discussions of its effects—from habitat loss to psychological impacts—can be found in most academic disciplines. Among the many casualties of contemporary climatic change is the archaeological heritage of Arctic and subarctic regions, as warming, erratic weather patterns, coastal erosion, and melting permafrost threaten the anthropogenic and ecological records found in northern environments. Archaeology is uniquely positioned to provide long-term perspectives on human responses to climatic shifts, and to inform on the current debate. In addition, the practice of archaeological research and assimilation of archaeological heritage into contemporary society can also address or even mitigate some of the sociocultural impacts of climate change. Focusing on the Yup’ik communities and critically endangered archaeology of the Yukon–Kuskokwim (Y–K) Delta, Alaska, here we argue community archaeology can provide new contexts for encountering and documenting the past, and through this, reinforce cultural engagement and shared cultural resilience. We emphasize the benefits of archaeological heritage and the practice of archaeology in mitigating some of the social and psychological impacts of global climate change for communities as well as individuals. We also propose that archaeology can have a role in reducing psychological distance of climate change, an acknowledged barrier that limits climate change action, mitigation, and adaptation, particularly in regions where the impacts of contemporary climate change have not yet been immediately felt.
Labrador Inuttut Inverted Number Marking: Ongoing Questions
Authors: Smith Lawrence R.
Published: November 2020

There is a fascinating and prima facie perplexing patterning in Inuttut, the Labrador dialect of Inuktitut, wherein the quite regular markers of singular and plural in verbal inflectional markers appear inverted in second person forms. We explore this linguistic problem and show two things: that progress toward a solution is facilitated by incorporating representations of linguistic intent, and also that the consideration of intent, by adding a level of data, opens the phenomenon for deeper understanding by presenting new hypotheses to be explored. Making such features available in grammatical derivations allows the systematic generation of patterns that would otherwise be impossible, thereby obviating gaps in the potential for grammatical explanation and highlighting psychologically plausible mechanisms for diachronic change. It is disadvantageous for any theory of grammatical competence to allow any phenomenon of strong grammatical patterning to remain unaccounted for. By viewing grammatical structures as the result of tool invention by individuals and groups in the linguistic past, the study of the intellectual history of linguistic innovation can potentially uncover particularly clever and insightful processes related to desiderata of cultural adhesion. This approach opens new hypotheses for the evolution of the language from the proto stage.
La caractérisation des personnages royaux en Mt 1-2
Authors: Doane Sébastien
Published: November 2020

Jésus, le protagoniste en Mt, est dépeint par une série de correspondances et d’oppositions avec les autres personnages royaux que sont David, Hérode et Archélaüs. Par une approche narrative, l’étude de la caractérisation de ces personnages souligne les aspects politiques des deux premiers chapitres de Mt. En outre, les renversements ironiques du début de l’évangile préparent les lecteurs à découvrir un royaume radicalement différent de celui d’Hérode ainsi qu’un messie, fils de David hors norme. Ainsi Mt 1-2 est le prélude du renversement final de cette oeuvre : le messie crucifié par les autorités de Jérusalem sera ressuscité par Dieu.
La construction de la temporalité et de l’espace dans quelques textes de l’Apocalypse de Jean
Authors: Cuvillier Elian
Published: November 2020

Cet article propose une manière d’appréhender le langage apocalyptique propre à Jean de Patmos à travers l’analyse de deux types de données : temporelles et spatiales. Il montre sa fécondité herméneutique et ainsi sa potentielle actualité pour appréhender le temps et l’espace qui sont les nôtres. La lecture de l’Apocalypse ouvre l’espace et le temps d’une imagination créatrice qui se veulent résolument en écart de l’angoisse et de l’enfermement caractérisant à maints égards notre monde présent.
Récits impériaux et contre-récits bibliques : les études littéraires comme support des Empire Studies
Authors: Hurley Robert
Published: November 2020

L’interprétation politique du NT a rencontré de sérieuses objections dans l’histoire de l’exégèse. Contre cette tendance, l’auteur tente ici une interprétation des récits néotestamentaires à l’aide de la critique idéologique. Plus spécifiquement, il interprète les évangiles comme contre-récit du récit dominant impérial en juxtaposant le Christ et l’empereur, les pratiques instituées de l’ekklēsia et celles de l’Empire. Cette comparaison s’appuie sur une analyse originale des rapports pouvant exister entre narrativité, religion et politique. La première étape de cette recherche consiste en une analyse de l’utilisation du genre narratif par des acteurs politiques ou religieux pour convaincre leur public de la viabilité de leur vision d’avenir.
Inovatīvu poliolu sistēmu izstrādne no reciklēta polietilēntereftalāta un atjaunojamo izejvielu resursiem cietā poliuretāna putuplasta iegūšanai
Authors:   , Ivdre Aiga
Published: November 2020

Promocijas darba mērķis ir izstrādāt inovatīvus, cietā PU putuplastu iegūšanai piemērotus poliolus no otrreiz pārstrādāta PET pārslām un atjaunojamo izejvielu resursiem (rapšu eļļas un taleļļas) un novērtēt poliolu ietekmi uz cieto PU putuplastu kā siltumizolācijas materiāla svarīgākajām īpašībām.
Determinants of Use of Social Media Platforms among Extension Professionals in Southwest, Nigeria
Authors: Babasanya Bankole , Akinola M. O. , Saddiq N. M. , Ojeleye O. M. , Usman M. B. , Ganiyu L. , Olorukooba M. M.
Published: November 2020

Opportunities to share and providing access to agricultural information at a much faster pace to a wider audience through a variety of user-friendly platforms can be achieved through the use of social media. This study investigated use of social media platforms among extension professionals in Southwest, Nigeria. Two hundred and five respondents were selected through multistage sampling and used for the study. The findings revealed that majority of respondents were between 36 and 50 years, 52.2% were male, 39.5% had B.Sc, 22.9% had HND, 15.1% had PGD, 12.2% had Ph.D and 10.2% had M,Sc/M.Phil, Over half (58%) of respondents had moderate awareness on use of WhatsApp for extension service delivery. Results of regression analysis showed positive and significant influence of performance expectancy (β=.199, p<.05), effort expectancy (β=.170, p<.05) and social influence (β=.139, p<.05) on use of social media platforms. From the result of the study, it was found that performance expectancy, effort expectancy and social influence were predictors of social media use, and recommended that in the use of social media for extension service delivery, these factors should be given attention in the study area.
Update of Regulatory Options of New Breeding Techniques and Biosafety Approaches among Selected Countries: A Review
Authors: Obukosia Silas , Akinbo Olalekan , Sinebo Woldeyesus , Savadogo Moussa , Timpo Samuel , Adeyemo Modupe , Akile Sunday , Kebere Jean , Ouedraogo Jeremy , Ambali Aggrey , Makinde Diran
Published: November 2020

A new set of breeding techniques, referred to as New Breeding Techniques developed in the last two decades have potential for enhancing improved productivity in crop and animal breeding globally. These include site directed nucleases based genomic editing procedures-CRISPR and Cas associated proteins, Zinc Finger Nucleases, Meganucleases/Homing Endonucleases and Transcription- Activator Like-Effector Nucleases for genome editing and other technologies including- Oligonucleotide-Directed Mutagenesis, Cisgenesis and intragenesis, RNA-Dependent DNA methylation; Transgrafting, Agroinfiltration, Reverse breeding. There are ongoing global debates on whether the processes of and products emerging from these technologies should be regulated as genetically modified organisms or approved as conventional products. Decisions on whether to regulate as GMOs are based both on understanding of the molecular basis of their development and if the GMO intermediate step was used. For example- cisgenesis, can be developed using Agrobacterium tumefaciens methods of transformation, a process used by GMO but if the selection is properly conducted the intermediate GMO elements will be eliminated and the final product will be identical to the conventionally developed crops. Others like Site Directed Nuclease 3 are regulated as GMOs in countries such as United State of America, Canada, European Union, Argentina, Australia. Progress in genome editing research, testing of genome edited bacterial blight resistant rice, development of Guidelines for regulating new breeding techniques or genome editing in Africa is also covered with special reference to South Africa, Kenya and Nigeria. Science- and evidence-based approach to regulation of new breeding techniques among regulators and policy makers should be strongly supported.
Effects of Anisotropy on Natural Convection in a Vertical Porous Cavity Filled with a Heat Generation
Authors: Gerard Degan , Ernest Sokpoli Amavi , Christian Akowanou Djidjoho , Claude Vodounnou Edmond
Published: November 2020

This research was devoted to the analytical study of heat transfer by natural convection in a vertical cavity, confining a porous medium, and containing a heat source. The porous medium is hydrodynamically anisotropic in permeability whose axes of permeability tensor are obliquely oriented relative to the gravitational vector and saturated with a Newtonian fluid. The side walls are cooled to the temperature  and the horizontal walls are kept adiabatic. An analytical solution to this problem is found for low Rayleigh numbers by writing the solutions of mathematical model in polynomial form of degree n of the Rayleigh number. Poisson equations obtained are solved by the modified Galerkin method. The results are presented in term of streamlines and isotherms. The distribution of the streamlines and the temperature fields are greatly influenced by the permeability anisotropy parameters and the thermal conductivity. The heat transfer decreases considerably when the Rayleigh number increases.
Paediatric Osteomyelitis in a Tertiary Hospital in South-South Nigeria; Clinical Experience at Federal Medical Centre Asaba
Authors: Emeagui N. K. , Obu G. O. , Opara H. I. O. , Emeagui O. D. , Ajaegbu O. C. , Esievoadje S. E. , Urhi A.
Published: November 2020

Background: The incidence of Osteomyelitis is disproportionately higher in low-income countries (43-200 per 100,000 children) compared to high-income countries (1.94-13 per 100,000 children).These infections remains a significant threat to proper growth and development of children in low-income countries, and this is partly due to late presentation to the hospital coupled with wanton unorthodox pre-hospital intervention by traditional healers.

Aim: To determine the clinical and microbiological profile of paediatric osteomyelitis at Federal Medical Centre Asaba.

Methods: This is a 4year single centre retrospective study of all paediatric osteomyelitis managed in this hospital from January 2014 to December 2018. Important data such as type (acute, subacute and chronic) of osteomyelitis, bone involved, bone sites (epiphyseal, metaphyseal or diaphyseal) affected, microbiological culture results (implicated microorganisms), and genotype, treatment and outcome of treatment were expressed as frequencies and mean ± standard deviations, and Pearson’s Chi square test was used to measure associations. P values ˂ .05 were considered statistically significant.

Results: Forty (40) out of 3657 children had osteomyelitis, 17 (42.5%), 4(10%) and 19 (47.5%) were diagnosed with acute, subacute and chronic osteomyelitis respectively. The prevalence of osteomyelitis in this study was 1%. The children were between the ages of 6 months to 17 years with a mean age of 8.1 ± 4.23 years and spent an average of 19 ± 14 days on admission. Low and middle socioeconomic status were significantly associated with the risk of infection (P = .04). Tibia (47.5%) and femur (25%) were the commonest bones involved. Staphylococcus aureus accounted for 52.5% of cases and the metaphysis was the commonest site involved. The sickle cell heamoglobin to normal heamoglobin genotype ratio is 1:3. Out-come was favourable 87.5% of the cases.

Conclusion: Low socioeconomic class is a risk factor for paediatric osteomyelitis in our locality. Early diagnosis and prompt treatment are vital in ensuring favourable outcome.
Multiatom Catalysts for Energy‐Related Electrocatalysis
Authors: Peng Wei , Feng Yiyang , Yan Xiao , Hou Feng , Wang Liqun , Liang Ji
Published: November 2020

Multiatom catalysts (MACs) with isolated monodisperse active sites comprising two to tens of metal atoms have attracted intensive research attention and industrial interest. With the combination of high atom utilization and well‐defined molecule‐like electronic structure, MACs show great potential for applications in a wide range of electrochemical catalytic reactions. This review aims to discuss the recent progress of MACs in energy‐related electrocatalysis. Critical issues, including the synthesis and characterization of the MACs, will be showcased. Moreover, recent advances are highlighted in the design and synthesis of MACs with a well‐controlled structure and composition to achieve enhanced catalytic performance in energy‐related electrocatalysis. Current challenges and future prospects for MACs are also presented to shed light on the rational design of MACs as potential industrialized catalysts in the future.
Assessing methods and obstacles in chemical space exploration
Authors: Reeves Shawn , DiFrancesco Benjamin , Shahani Vijay , MacKinnon Stephen , Windemuth Andreas , Brereton Andrew E.
Published: November 2020

Benchmarking the performance of generative methods for drug design is complex and multifaceted. In this report, we propose a separation of concerns for de novo drug design, categorizing the task into three main categories: generation, discrimination and exploration. We demonstrate that changes to any of these three concerns impacts benchmark performance for drug design tasks. In this report, we present Deriver, an open‐source Python package that acts as a modular framework for molecule generation, with a focus on integrating multiple generative methods. Using Deriver, we demonstrate that changing parameters related to each of these three concerns impacts chemical space traversal significantly, and that the freedom to independently adjust each is critical to real‐world applications having conflicting priorities. We find that combining multiple generative methods can improve optimization of molecular properties and lower the chance of becoming trapped in local minima. In addition, filtering molecules for drug‐likeness (based on physicochemical properties and SMARTS pattern matching) before they are scored may hinder exploration, but can also improve the quality of the final molecules. Finally, we demonstrate that any given task has an exploration algorithm best suited to it, though in practice linear probabilistic sampling generally results in the best outcomes, when compared to Monte Carlo sampling or greedy sampling. Deriver is being made freely available, to help others interested in collaboratively improving existing methods in de novo drug design centered around inheritance of molecular structure, modularity, extensibility, and separation of concerns.
Peak values of twist‐to‐bend ratio in triangular flower stalks of Carex pendula: a study on biomechanics and functional morphology
Authors: Speck Olga , Steinhart Feray , Speck Thomas
Published: November 2020

Premise

Because of their own weight and additional wind forces, plants are exposed to various bending and torsional loads that sometimes require contradictory structural characteristics and mechanical properties. The resulting trade‐off between flexural and torsional rigidity can be quantified and compared using the dimensionless twist‐to‐bend ratio.

Methods

The flexural rigidity of the stems of Carex pendula was determined by 2‐point bending tests. Additionally, 4‐point bending tests and torsional tests were carried out on segments of two internodes directly below the inflorescences to measure flexural and torsional rigidity. Anatomical investigations were performed to quantify the cross‐sectional distribution of their tissues.

Results

The flexural rigidity of the stems, segments of the apical internode 1, and the more basal internode 2 differed significantly from each other, whereas the bending elastic moduli were not significantly different. The torsional rigidity of segments of internode 2 was a factor of 3.3 higher than that of internode 1, whereas the torsional moduli did not differ significantly. The twist‐to‐bend ratios of segments of internode 1 and 2 reached values between 85 and 403. Light microscopic investigations revealed a triangular stem possessing individual sclerenchyma strands, with internode 2 having significantly more strands than internode 1.

Conclusions

In the case of Carex pendula, flexural and torsional rigidity are adapted to the given mechanical constraints by significant changes in morphometric variables (axial and polar second moment of area, number of sclerenchyma strands), whereas the material properties (bending and torsional modulus) do not change markedly along the stem.
Light availability influences the intensity of nectar robbery and its effects on reproduction in a tropical shrub via multiple pathways
Authors: Fitch Gordon , Vandermeer John H.
Published: November 2020

Premise

The multiple exogenous pathways by which light availability affects plant reproduction (e.g., via influence on attraction of mutualists and antagonists) remain surprisingly understudied. The light environment experienced by a parent can also have transgenerational effects on offspring via these same pathways.

Methods

We evaluated (a) the influence of light availability on floral traits in Odontonema cuspidatum, (b) the relative importance of the pathways by which light influences nectar robbery and reproductive output, and (c) the role of parental light environment in mediating these relationships. We conducted a reciprocal translocation experiment using clonally propagated ramets and field surveys of naturally occurring plants.

Results

Light availability influenced multiple floral traits, including flower number and nectar volume, which in turn influenced nectar robbery. But nectar robbery was also directly influenced by light availability, due to light effects on nectar robber foraging behavior or neighborhood floral context. Parental light environment mediated the link between light availability and nectar robber attraction, suggesting local adaptation to low‐light environments in floral visitor attraction. However, we found no transgenerational effect on reproduction.

Conclusions

Our findings demonstrate that exogenous pathways by which light influences plants (particularly through effects on floral antagonists) can complicate the positive relationship between light availability and plant reproduction. Our results are among the first to document effects of light on floral antagonists and clonal transgenerational effects on flower visitor attraction traits.
Accelerated senescence as a cost of reproduction: Testing associations between oxidative stress and reproductive effort in rural and urban women
Authors: Sancilio Amelia , Jasienska Grazyna , Panter‐Brick Catherine , Ziomkiewicz Anna , Nenko Ilona , Bribiescas Richard G.
Published: November 2020

Objectives

Oxidative stress is hypothesized to contribute to age‐related somatic deterioration. Both reproductive and ecological context may necessitate tradeoffs that influence this outcome. We examined whether measures of lifetime reproductive effort were related to levels of oxidative stress biomarkers in peri‐ and post‐menopausal women and whether associations were moderated by rural or urban residence.

Methods

We surveyed 263 healthy women (age 62.1 ± 10.0 SD) from rural (N = 161) and urban Poland (N = 102), collecting sociodemographic data and urine samples to analyze biomarkers of oxidative stress (8‐oxo‐2′‐deoxyguanosine, 8‐OHdG) and antioxidative defense (copper‐zinc superoxide dismutase, Cu‐Zn SOD). Linear regression models, adjusted for residence, were used to test for associations between reproductive effort and 8‐OHdG and Cu‐Zn SOD.

Results

Univariate models demonstrated significant associations between gravidity and the biomarkers of oxidative stress (8‐OHdG: R2 = 0.042, P ≤ .001; Cu‐Zn SOD: R2 = 0.123, P ≤ .001). Multivariate models incorporating potential confounding variables, as well as cross‐product interaction terms, indicated that gravidity was associated with 8‐OHdG (P < .01, R2adj = 0.067) and Cu‐Zn SOD (P = .01, R2adj = 0.159). Residence (ie, urban vs rural) did not significantly moderate the associations between the biomarkers and reproductive effort.

Conclusions

Higher lifetime reproductive effort contributes to increases in oxidative stress and antioxidative defenses. Our results provide evidence of potential mechanisms underlying the physiological tradeoffs influencing senescence for women with high reproductive effort. We illustrate the value of applying an evolutionary perspective to elucidate variation in human health and senescence.
Electron microscopic study of the median structure of the posterior column of the spinal cord of the adult rat with a special reference to the posterior median septum
Authors: Mii Kimihiko , Yagishita Saburo , Kumabe Toshihiro
Published: November 2020

In neuroanatomy textbooks on humans, the posterior median septum is commonly depicted along the midline of the posterior column of the spinal cord. For intramedullary spinal cord tumors, the standard surgical treatment is posterior midline myelotomy. However, its anatomical basis is still unclear. Therefore, in this study we focused on the ultrastructural characterization of the median structure of the posterior column in an adult rat. In the median part of the fasciculi gracilis, a fine lineal tissue continued from the posterior median sulcus to the 3/4th depth of the fasciculi. At higher magnification, this fine lineal tissue consisted of bundles of astrocytes, which are often disrupted and eventually disappeared. At the junction of the ventral part of the fasciculi cuneatus and the gray commissure, short lineal figures of glial tissues extended dorsally. These lineal figures of glial tissues were morphologically similar to other lineal figures of glial tissues found in the posterior column; bundles of astrocytes extending along the axons that entered the gray commissure and the perivascular lineal figures of glial tissues. In conclusion, this study revealed that the posterior median septum is composed of very fine lineal figures of glial tissues that are often disrupted and eventually disappear. We consider these basic structures to be similar in humans. Therefore, during posterior midline myelotomy, accurately separating along the posterior median septum in the posterior column is extremely difficult.
Odontoblast processes of the mouse incisor are plates oriented in the direction of growth
Authors: Shuhaibar Ninna , Hand Arthur R. , Terasaki Mark
Published: November 2020

Odontoblast processes are thin cytoplasmic projections that extend from the cell body at the periphery of the pulp toward the dentin‐enamel junction. The odontoblast processes function in the secretion, assembly and mineralization of dentin during development, participate in mechanosensation, and aid in dentin repair in mature teeth. Because they are small and densely arranged, their three‐dimensional organization is not well documented. To gain further insight into how odontoblast processes contribute to odontogenesis, we used serial section electron microscopy and three‐dimensional reconstructions to examine these processes in the predentin region of mouse molars and incisors. In molars, the odontoblast processes are tubular with a diameter of ~1.8 μm. The odontoblast processes near the incisor tip are similarly shaped, but those midway between the tip and apex are shaped like plates. The plates are radially aligned and longitudinally oriented with respect to the growth axis of the incisor. The thickness of the plates is approximately the same as the diameter of molar odontoblast processes. The plates have an irregular edge; the average ratio of width (midway in the predentin) to thickness is 2.3 on the labial side and 3.6 on the lingual side. The plate geometry seems likely to be related to the continuous growth of the incisor and may provide a clue as to the mechanisms by which the odontoblast processes are involved in tooth development.
Impact of various ecological parameters on the life‐history characteristics of Bufotes viridis sitibundus from Turkey
Authors: Altunışık Abdullah , Gül Serkan , Özdemir Nurhayat
Published: November 2020

In this study, we used the skeletochronology method to estimate various growth parameters, such as age structure, minimum and maximum life span, age of sexual maturity, and the relationship between body size and weight of eight different populations of the variable toad, Bufotes viridis sitibundus, in Turkey. Further, we determined the relationship between these parameters and ecologic factors using the partial Mantel test. A significant difference was found among the populations with respect to age, body size, and body weight in both males and females. On average, the maximum life span was recorded as 10 years for males and 11 years for females. In the studied populations, the average age of sexual maturity ranged between 2 and 4 years for both sexes. Sexual dimorphism in terms of snout‐vent length (SVL) was not observed between males and females in all the populations. Toads from the higher altitudes tended to be significantly larger, older, and heavier than those from lower altitudes. We concluded that altitude and temperature have an impact on the growth rate, body size, and body mass.
X‐ray Powder Diffraction Study of Molybdenum Oxides Formed From the Thermal Reactions of MoS2, MoS2/LiF, and MoS2/Ag in Air
Authors: Lee So‐Ram , Kim Youhyuk
Published: November 2020

MoS2 can generate useful molybdenum oxides by thermally reacting with LiF or Ag nanoparticles (NPs). MoS2 easily loses sulfide and reacts with oxygen gas upon heating in air to give orthorhombic molybdenum trioxide, α‐MoO3. Morphological changes of α‐MoO3 from 500 to 900°C were investigated using X‐ray powder diffraction and scanning electron microscope. The strong diffraction peaks of the (020), (040), and (060) planes at 800°C revealed highly anisotropic growth of the oxides with a layered crystal structure. In the presence of LiF, MoS2 reacts with oxygen gas to generate Li2MoO4 and MoO2, depending on the LiF concentration. In the presence of Ag NPs, the thermal reactions of MoS2 at 800 and 900°C give silver molybdates Ag2Mo2O7 and Ag2MoO4, respectively. These results demonstrate that MoS2 is an important precursor for generating useful molybdenum oxides on the surface of inert substrates without requiring sophisticated, expensive equipment.
Effects of variable domain orientation on anti‐HER2 single‐chain variable fragment antibody expressed in the Escherichia coli cytoplasm
Authors: Koçer İlkay , Cox Emily C. , DeLisa Matthew P. , Çelik Eda
Published: November 2020

Single‐chain variable fragment (scFv) antibodies have great potential for a range of applications including as diagnostic and therapeutic agents. However, production of scFvs is challenging because proper folding and activity depend on the formation of two intrachain disulfide bonds that do not readily form in the cytoplasm of living cells. Functional expression in bacteria therefore involves targeting to the more oxidizing periplasm, but yields in this compartment can be limiting due to secretion bottlenecks and the relatively small volume compared to the cytoplasm. In the present study, we evaluated an anti‐HER2 scFv, which is specific for human epidermal growth receptor 2 (HER2) overexpressed in breast cancer, for functional expression in the cytoplasm of Escherichia coli strains BL21(DE3) and SHuffle T7 Express, the latter of which is genetically engineered for cytoplasmic disulfide bond formation. Specifically, we observed much greater solubility and binding activity with SHuffle T7 Express cells, which likely resulted from the more oxidative cytoplasm in this strain background. We also found that SHuffle T7 Express cells were capable of supporting high‐level soluble production of anti‐HER2 scFvs with intact disulfide bonds independent of variable domain orientation, providing further evidence that SHuffle T7 Express is a promising host for laboratory and preparative expression of functional scFv antibodies.
Consolidated plasmid Design for Stabilized Heterologous Production of the complex natural product Siderophore Yersiniabactin
Authors: Qi Ruiquan , Swayambhu Girish , Bruno Michael , Zhang Guojian , Pfeifer Blaine A.
Published: November 2020

Yersiniabactin (Ybt) is a hybrid polyketide‐nonribosomal complex natural product also known as a siderophore for its iron chelation properties. The native producer of Ybt, Yersinia pestis, is a priority pathogen responsible for the plague in which the siderophore properties of Ybt are used to sequester iron and other metal species upon host infection. Alternatively, the high metal binding properties of Ybt enable a plethora of potentially valuable applications benefiting from metal remediation and/or recovery. For these applications, a surrogate production source is highly preferred relative to the pathogenic native host. In this work, we present a modification to the heterologous Escherichia coli production system established for Ybt biosynthesis. In particular, the multiple plasmids originally used to express the genetic pathway required for Ybt biosynthesis were consolidated to a single, copy‐amplifiable plasmid. In so doing, plasmid stability was improved from ~30% to ≥80% while production values maintained at 20–30% of the original system, which resulted in titers of 0.5–3 mg/L from shake flask vessels.
Develop a circular RNA–related regulatory network associated with prognosis of gastric cancer
Authors: Wei Shuxun , Teng Shifeng , Yao Jun , Gao Wenchao , Zang Jia , Wang Guangyong , Hu Zhiqian
Published: November 2020

Background

In gastric cancer (GC), circular RNAs (circRNAs) mainly play an important role in miRNA sponge, which not only indicate long‐term survival and prognosis but also increase resistance to the apoptosis. The purpose of the study is to explore new circRNAs and their underlying mechanisms in GC.

Method

Through rigorous retrieval strategies, we used the sva package to analyze and identify differentially expressed circRNAs (DECs) from three Gene Expression Omnibus microarray datasets (GSE83521, GSE89143, and GSE78092). Online website CSCD and CircInteractome were used to reveal the binding sites between miRNAs and DECs. The possible target miRNAs of the DECs identified based on miRNAs, and Cytoscape was used to create a regulatory network of circRNA‐miRNA‐mRNA and identified the hub genes which were further validated using The Cancer Genome Atlas database and Human Protein Atlas.

Results

Twenty‐eight DECs were obtained using the sva package. A regulatory network of circRNA‐miRNA‐mRNA (competing endogenous RNA) containing 15 circRNAs, 24 miRNAs, and 158 genes was identified. A protein‐protein interaction network based on the 158 genes was established, and further determined that 10 hub genes (SKA1, ANLN, CHEK1, SKA3, TOP2A, BIRC5, RRM2, NCAPG2, FANCI, and RAD51) were associated with some cancer‐related pathways based on the functional enrichment analysis. Finally, six hub genes (BIRC5, TOP2A, FANCI, NCAPG2, RAD51, and RRM2) were proven to influence the overall survival of GC.

Conclusion

Our study established a circRNA‐miRNA‐mRNA regulatory network and defined six circRNA‐related hub genes in GC, which could serve as potential therapeutic targets or prognostic biomarker for GC treatment.
Correlation of tumor‐infiltrating immune cells of melanoma with overall survival by immunogenomic analysis
Authors: Huang Lili , Chen Hong , Xu Yu , Chen Jianhua , Liu Zhuqing , Xu Qing
Published: November 2020

Aims

Different types of tumor‐infiltrating immune cells not only augment but also dampen antitumor immunity in the microenvironment of melanoma. Therefore, it is critical to provide an overview of tumor‐infiltrating immune cells in melanoma and explore a novel strategy for immunotherapies.

Methods

We analyzed the immune states of different stages in melanoma patients by the immune, stromal, and estimation of stromal and immune cells in malignant tumor tissues using expression data (ESTIMATE) scores. Immune cell types were identified by the estimating relative subsets of RNA transcripts (CIBERSORTx) algorithm in 471 melanoma and 324 healthy tissues. Moreover, we performed a gene set variation analysis (GSVA) to determine the differentially regulated pathways in the tumor microenvironment.

Results

In melanoma cohorts, we found that ESTIMATE and immune scores were involved in survival or tumor clinical stage. Among the 22 immune cells, CD8+ T cells, M2 macrophages, and regulatory T cells (Tregs) showed significant differences using the CIBERSORTx algorithm. Furthermore, GSVA identified the immune cell‐related pathways; the primary immunodeficiency pathway, intestinal immune network for IgA, and TGF‐β pathways were identified as participants of the crosstalk in CD8+ T cells, Tregs, and M2 macrophages in the melanoma microenvironment.

Conclusion

These results reveal the cellular and molecular characteristics of immune cells in melanoma, providing a method for selecting targets of immunotherapies and promoting the efficacy of therapies for the treatment of melanoma.
Corymbia citriodora: A Valuable Resource from Australian Flora for the Production of Fragrances, Repellents, and Bioactive Compounds
Authors: Goodine Tyler , Oelgemöller Michael
Published: November 2020

As global chemical manufacturing has historically relied on inexpensive feedstocks from the petrochemical industry, the identification of new naturally derived feedstocks represents an important and sustainable alternative. This review introduces Corymbia citriodora (Hook.) K.D.Hill & L.A.S.Johnson as an attractive renewable resource of natural compounds for organic chemical transformations. Although native to Australia, this plant species is now grown and harvested worldwide. The chemical composition of citriodora oils varies with location, harvesting season and age of leaves. Beyond their historic uses as fragrances or repellents, the more abundant terpenes found in citriodora oils such as citronellal, citronellol, and isopulegol have notable roles in the manufacture of fine chemicals. This review highlights several industrial processes intimately related to the citriodora terpenes, some advances in fragrances and repellents, as well as the use of these terpenes in the most recently reported synthesis of bioactive compounds. Where relevant, processes highlighting the adoption of green chemistry principles are presented and briefly discussed.
Evaluations of the capacity of an existing brine system and estimation of salt loading profile for increased soft water demand to avoid soil contamination
Authors: Sharma Deepak , Karre Avinashkumar V. , Valsaraj Kalliat T.
Published: November 2020

As part of the expansion of a new chemical manufacturing facility, the debottlenecking of an existing brine system for an increase in soft water demand and the usefulness of the method was studied. Mathematical equations were used to estimate the salt loading profile. The effect of increasing soft water demand on the brine system was studied using parameters such as the amount of salt, the number of refills of brine tank, the brine pump run time, the number of days for the salt pit to empty, and the number of brine truck deliveries. The generalized mathematical equations derived and presented in this study can be used for any debottlenecking studies. The study showed that the existing brine pit and brine pumps can be reused for the future brine demand. The study showed with a good truck delivery logistics and a robust pit maintenance program, the number of regenerations can be increased while utilizing the existing brine pit system. The risk level remained the same as in existing pit systems since an increase in the frequency of pit maintenance was used to account for higher brine levels in the pit. The study methodology can be utilized for similar brine and softener systems in plant expansion operations to avoid a new pit system and to reduce capital costs. Brine seepage through the new concrete walls was avoided effectively. A polyvinyl chloride above ground tank system is recommended for brine service in all future projects where feasible.
Polyhedral Oligomeric Silsesquioxanes (POSS)‐based Hybrid Materials: Molecular Design, Solution Self‐Assembly and Biomedical Applications
Authors: Fan Linfeng , Wang Xing , Wu Decheng
Published: November 2020

Owing to the tremendous advantages and unique well‐defined nanoscale structure, polyhedral oligomeric silsesquioxanes (POSS) have received considerable interest in the design of novel organic‐inorganic hybrid nanomaterials with all manner of prominent capabilities, which is recognized as a new generation of promising materials for advanced applications of material science, engineering science and biomedical fields. Benefitting from the recent progress in combination of controlled/living polymerization and emerging click chemistry, POSS‐based hybrid materials with ingenious design, versatile topological structure and sophisticated multifunctionality have been successfully fabricated and developed into abundant well‐defined hybrid nanostructures with desired physicochemical properties. Tailor‐made amphiphilic molecular design and nanosized hybrid architecture provide opportunities for the self‐assembly of POSS‐based hybrid materials with unique hierarchical morphologies in selective solvents. Through the in‐depth understanding of structure‐properties relationship, POSS‐based hybrid materials can achieve the modulation of precise control of self‐assembling process and multi‐purpose applications with improved material performances. In this review, we summarize the recent advances of POSS‐based hybrid materials in molecular design, self‐assembly behavior in solutions and potential biomedical applications with main concerns on drug delivery, gene therapy, bioimaging and tissue engineering field. Finally, future directions and remaining challenges for further advancement of POSS‐based hybrid materials are proposed and discussed.
Morphological identification of thoracolumbar spinal afferent nerve endings in mouse uterus
Authors: Dodds Kelsi N. , Kyloh Melinda A. , Travis Lee , Beckett Elizabeth A. H. , Spencer Nick J.
Published: November 2020

Major sensory innervation to the uterus is provided by spinal afferent nerves, whose cell bodies lie predominantly in thoracolumbar dorsal root ganglia (DRG). While the origin of the cell bodies of uterine spinal afferents is clear, the identity of their sensory endings has remained unknown. Hence, our major aim was to identify the location, morphology, and calcitonin gene‐related peptide (CGRP)‐immunoreactivity of uterine spinal afferent endings supplied by thoracolumbar DRG. We also sought to determine the degree of uterine afferent innervation provided by the vagus nerve. Using an anterograde tracing technique, nulliparous female C57BL/6 mice were injected unilaterally with biotinylated dextran into thoracolumbar DRG (T13‐L3). After 7–9 days, uterine horns were stained to visualize traced nerve axons and endings immunoreactive to CGRP. Whole uteri from a separate cohort of animals were injected with retrograde neuronal tracer (DiI) and dye uptake in nodose ganglia was examined. Anterogradely labeled axons innervated each uterine horn, these projected rostrally or caudally from their site of entry, branching to form varicose endings in the myometrium and/or vascular plexus. Most spinal afferent endings were CGRP‐immunoreactive and morphologically classified as “simple‐type.” Rarely, uterine nerve cell bodies were labeled in nodose ganglia. Here, we provide the first detailed description of spinal afferent nerve endings in the uterus of a vertebrate. Distinct morphological types of spinal afferent nerve endings were identified throughout multiple anatomical layers of the uterine wall. Compared to other visceral organs, uterine spinal afferent endings displayed noticeably less morphological diversity. Few neurons in nodose ganglia innervate the uterus.
CB2 receptor‐selective agonists as candidates for targeting infection, inflammation, and immunity in SARS‐CoV‐2 infections
Authors: Nagoor Meeran M. F. , Sharma Charu , Goyal Sameer N. , Kumar Sanjay , Ojha Shreesh
Published: November 2020

The COVID‐19 pandemic caused by SARS‐CoV‐2 is a deadly disease afflicting millions. The pandemic continues affecting population due to nonavailability of drugs and vaccines. The pathogenesis and complications of infection mainly involve hyperimmune‐inflammatory responses. Thus, therapeutic strategies rely on repurposing of drugs aimed at reducing infectivity and inflammation and modulate immunity favourably. Among, numerous therapeutic targets, the endocannabinoid system, particularly activation of cannabinoid type‐2 receptors (CB2R) emerged as an important one to suppress the hyperimmune‐inflammatory responses. Recently, potent antiinflammatory, antiviral and immunomodulatory properties of CB2R selective ligands of endogenous, plant, and synthetic origin were showed mediating CB2R selective functional agonism. CB2R activation appears to regulate numerous signaling pathways to control immune‐inflammatory mediators including cytokines, chemokines, adhesion molecules, prostanoids, and eicosanoids. Many CB2R ligands also exhibit off‐target effects mediating activation of PPARs, opioids, and TRPV, suggestive of adjuvant use with existing drugs that may maximize efficacy synergistically and minimize therapeutic doses to limit adverse/ side effects. We hypothesize that CB2R agonists, due to immunomodulatory, antiinflammatory, and antiviral properties may show activity against COVID‐19. Based on the organoprotective potential, relative safety, lack of psychotropic effects, and druggable properties, CB2R selective ligands might make available promising candidates for further investigation.
Centennial clonal stability of asexual Daphnia in Greenland lakes despite climate variability
Authors: Dane Maison , Anderson Nicholas John , Osburn Christopher L. , Colbourne John K. , Frisch Dagmar
Published: November 2020

Climate and environmental condition drive biodiversity at many levels of biological organization, from populations to ecosystems. Combined with paleoecological reconstructions, palaeogenetic information on resident populations provides novel insights into evolutionary trajectories and genetic diversity driven by environmental variability. While temporal observations of changing genetic structure are often made of sexual populations, little is known about how environmental change affects the long‐term fate of asexual lineages. Here, we provide information on obligately asexual, triploid Daphnia populations from three Arctic lakes in West Greenland through the past 200–300 years to test the impact of environmental change on the temporal and spatial population genetic structure. The contrasting ecological state of the lakes, specifically regarding salinity and habitat structure may explain the observed lake‐specific clonal composition over time. Palaeolimnological reconstructions show considerable regional environmental fluctuations since 1,700 (the end of the Little Ice Age), but the population genetic structure in two lakes was almost unchanged with at most two clones per time period. Their local populations were strongly dominated by a single clone that has persisted for 250–300 years. We discuss possible explanations for the apparent population genetic stability: (a) persistent clones are general‐purpose genotypes that thrive under broad environmental conditions, (b) clonal lineages evolved subtle genotypic differences unresolved by microsatellite markers, or (c) epigenetic modifications allow for clonal adaptation to changing environmental conditions. Our results motivate research into the mechanisms of adaptation in these populations, as well as their evolutionary fate in the light of accelerating climate change in the polar regions.
Generalized model‐based solutions to false‐positive error in species detection/nondetection data
Authors: Clare John D. J. , Townsend Philip A. , Zuckerberg Benjamin
Published: November 2020

Detection/nondetection data are widely collected by ecologists interested in estimating species distributions, abundances, and phenology, and are often imperfect. Recent model development has focused on accounting for both false‐positive and false‐negative errors given evidence that misclassification is common across many sampling protocols. To date, however, model‐based solutions to false‐positive error have largely addressed occupancy estimation. We describe a generalized model structure that allows investigators to account for false‐positive error in detection/nondetection data across a broad range of ecological parameters and model classes, and demonstrate that previously developed model‐based solutions are special cases of the generalized model. Simulation results demonstrate that estimators for abundance and migratory arrival time ignoring false‐positive error exhibit severe (20–70%) relative bias even when only 5–10% of detections are false positives. Bias increased when false‐positive detections were more likely to occur at sites or within occasions in which true positive detections were unlikely to occur. Models accounting for false‐positive error following the site‐confirmation or observation‐confirmation designs generally reduced bias substantially, even when few detections were confirmed as true or false positives or when the process model for false‐positive error was misspecified. Results from an empirical example focusing on gray fox (Urocyon cinereoargenteus) abundance in Wisconsin, USA reinforce concerns that biases induced by false‐positive error can also distort spatial predictions often used to guide decision making. Model sensitivity to false‐positive error extends well beyond occupancy estimation, but encouragingly, model‐based solutions developed for occupancy estimators are generalizable and effective across a range of models widely used in ecological research.