bluuebunny/crossref_metadata_2025 huggingface dataset:
‘On behalf of the city’: wax and urban diplomacy in the late medieval Baltic and North Sea
Authors: Whelan Mark
Published: August 2021

Focusing on the largely unpublished ‘city accounts’ (‘Stadsrekeningen’) of Bruges, this article examines the city's giving of prestigious Baltic beeswax to their lords, the Valois and (later) Habsburg dukes of Burgundy. It sheds new light on urban government by analysing how civic leaders across north-western Europe used the apiary product to manage often fraught relationships with their rulers and reinforce their identities as trading centres or outposts of international repute. More broadly, the gifting of Baltic beeswax points to the political and diplomatic prestige associated with the trade and display of the commodity in the later medieval period and the desire of urban leaders and communities to extract symbolic and political capital from its exchange.
What Is to Be Done? A Look at Some Causes and Consequences of the African Brain Drain
Authors: Sefa Dei George J. , Asgharzadeh Alireza
Published: August 2021

Defined primarily in terms of the exodus of the highly talented from the Southern countries to the North, the phenomenon known as “brain drain” has gained in importance during recent decades and years. Changing global conditions, unprecedented developments in information and electronic technology, globalization, and widening of the gap between the South and the North have focused attention on the brain drain. We begin this article by discussing the nature of the brain drain, briefly noting that it occurs in three settings: internal, regional, and global. Our argument here is that brain drain occurs in almost all societies, initially from poorer and impoverished rural areas to relatively rich and developing urban centers within national boundaries and later (or sometimes concurrently) to more developed and wealthy regions and neighboring countries.
The Second Boat of Africa’s New Diaspora: Looking at the Other Side of the Global Divide with an Emphasis on Sudan
Authors: Elnur Ibrahim
Published: August 2021

“Even if you cannot relocate to Nigeria immediately, visit home to see in which way you can lend a hand in rebuilding the country,” said Nigeria’s first lady Stella Obasanjo, on a recent visit to Cape Town, South Africa.

“My dad thought I was crazy for coming back,” said Osifo with a hearty laugh. “People are looking for ways to get out.”

“Why are you coming back?” (Singer 2001).

The processes of globalization have accelerated the exodus of the highly skilled from the collapsing modernization project. This article suggests that the flight of the educated elite is linked to the relative strength of the nation-state and both the length and intensity of internal conflicts. It is also suggested that the “skills exodus” may represent a major disruption in the political and social development of Africa, leading to further marginalization and affecting Africa’s capacity to revive development or envision an alternative development path. The emphasis is on Sudan’s unprecedented massive skills exodus during the past three decades, suggesting that this one case is extremely relevant to the rest of the continent, given the country’s favorable situation at the time of its independence in 1956.
Affirmative Action versus Nonracialism in the New South Africa
Authors: Waddy Nicholas L.
Published: August 2021

Last year, a distant cousin, who also happens to be a white South African, sent me a fascinating article from her local newspaper. The article was about her husband’s family, the Moores, and specifically about a claim the family made recently with South Africa’s Commission on Restitution of Land Rights (see Segar 2003). The claim is remarkable, because it has been one of the few lodged by white South Africans to obtain compensation for land that was taken from them under the apartheid regime. It seems that in 1965, several trading stores that had been owned by the Moores since the 1880s were confiscated by the South African Bantu Trust because they stood on land that was to become part of the independent black homeland known as the Transkei. The confiscation and the family’s eviction from the area were deeply traumatic—they were uprooted from their home, separated from friends and loyal customers (including Xhosa), and forced to witness the end of a family tradition. But the Moores had no choice, and the government offered them only one-third of the real value of the property as compensation. Today the family is seeking restitution, but as with most of the injustices perpetrated under apartheid, there is little that can be done to restore a way of life that was destroyed long ago.
Executive Director’s Foreword
Authors: Jones Loree
Published: August 2021

At its spring 2000 meeting, the African Studies Association Board of Directors voted unanimously to change the name of this journal from Issue: A Journal of Opinion to African Issues, indicating that it is a serious, forward-thinking scholarly journal that is an information source for policy makers and a useful resource for teaching about Africa.
Study Abroad in Africa: A Survey
Authors: Pires Mark , Marajh Oumatie , Metzler John
Published: August 2021

The National Consortium for Study in Africa (NCSA), established in 1994 by the 15 Title VI National Resource Centers for African Language and Area Studies, with financial support from the Fund for the Improvement of Postsecondary Education, maintains as one of its primary goals the promotion of high-quality study-abroad programs in Africa for American students and faculty. Through its work, the NCSA hopes to enhance opportunities for a larger number of students to benefit from a study-abroad educational experience in an African setting. Special emphasis will be placed on increasing the participation of minority students who tend to be underrepresented in such programs.
Strengthening Reciprocity in Study-Abroad Programs
Authors: Metzler John
Published: August 2021

The National Consortium for Study in Africa (NCSA) was founded in 1994 by the then 15 National Resource Centers for African Language and Area Studies. The primary agenda of the NCSA is to promote high-quality and accessible study-abroad programs for North American students in Africa. In addressing this agenda the NCSA initial membership had a particular, but not exclusive, interest in programs at African universities for North American students. This particular bias develops out of a long-standing commitment on the part of National Resource Centers to work with peer institutions in Africa. African universities, their faculty, and their students are essential partners in collaborative initiatives in research, teaching, and project work, and in the continuing process of generating knowledge on Africa across the disciplines. Consequently, from its inception the NCSA has viewed its goal of expanding high-quality programming in Africa as a natural outgrowth and expansion of its members’ linkages with African universities.
Africa-to-Africa: A Responsible Alternative to Study Abroad for 21st-century African Scholarship
Authors: Camara Mohamed Saliou
Published: August 2021

African scholars and activists often suggest that study-abroad programs to Africa be transformed to include an Africa-to-Africa exchange component. Their argument often includes discussion of the possibility that conventional study-abroad programs might perpetuate a colonial relationship between rich nations and those of the African continent rather that developing new relationships among African citizen diplomats. The following is an excellent overview of this debate.
American Study-Abroad Programs and the African University
Authors: Delehanty James M. , Raducha Joan A.
Published: August 2021

This article discusses the establishment of student-based linkages between U.S. and African universities, especially those based on study abroad. Specifically, it focuses on two dimensions of study-abroad linkages: the terms under which they are established and operate; and how to address, within the current structure of most African universities, the need that American programs have for an on-site support structure for their students. This article is part of a larger, ongoing project evaluating the development of study-abroad opportunities in Africa for U.S. students. A key focus of the study is to expand understanding of the support for such programs within African universities.
How to Support and Expand Strong, Existing Study-Abroad Programs: The Elon College Experience
Authors: Glaesel Heidi
Published: August 2021

Since the beginning of Elon College’s study-abroad program 30 years ago, it has been an ever-expanding part of the Elon academic program. Indeed, 46 percent of May 1999 Elon graduates participated in study abroad, ranking Elon second in the country among comprehensive colleges and universities for the percentage of students who study abroad. This short article summarizes some recent activities undertaken at Elon College that support its strong study-abroad program. Cost and time commitment vary by activity.
Study Abroad in Kenya: Now and in the Future
Authors: Kanani Simeon S.
Published: August 2021

As Kenya’s inbound tourism takes center stage as the country’s biggest income earner, study-abroad programs have emerged as the fastest growing subsector of the industry, making the country one of Africa’s most popular study-abroad destinations. In 1999 alone, a total of 22 credit-awarding academic study-abroad programs were operating in Kenya, an increase from 15 programs in 1998. Out of these 22 programs, 15 were from the United States, four were from Europe, and one was from Japan. In contrast, there were more than 80 noncredit study-abroad programs in 1999, most of which were short two-week study tours or field observation excursions. Of the noncredit study-abroad programs, 62 were from different African countries while 14 were from Europe and 12 were from the United States. This article describes the credit-awarding study-abroad programs and focuses on the University of Minnesota Studies in International Development (MSID) Kenya program.
Africanizing HBCUs: Problems and Prospects of International Education in Historically Black Institutions
Authors: Akomolafe Olusoji
Published: August 2021

Every projection indicates that minorities will represent a significant portion of the American labor force in the nearest future. Yet minority groups have historically represented segments of the population least capable of competing in the national and international marketplace. This is precisely why historically Black colleges and universities (HBCUs) need to rise to the challenge through an implicit mandate to internationalize their member institutions and the surrounding communities. This paper takes a critical look at how HBCUs ran the two most predominant components of international education, namely, the overseas and area studies programs. The main focus of the paper is Africa. It is indeed an attempt to assess the status of international education at HBCUs, particularly the problems they encounter as they struggle to internationalize. Although in the last few years, study abroad in Africa has become increasingly popular among HBCUs, the road ahead is still very long and sometimes tortuous. In the area of African studies, most of these institutions have a much bigger challenge to meet. The basic premise of my assumption is that despite all the good intentions of the government and private donor organizations, the fact remains that sustainable and qualitative international education in the area of African studies is in large part unaffordable and thus inaccessible to most HBCUs. Numerous factors are responsible for this phenomenon.
Experiencing Race and Class Social Structures
Authors: McCoy Molly
Published: August 2021

Spending time with a Senegalese family is essential to learn about life in Senegal. People in the family are happy to teach about their culture, lives, and language. Most important, they are willing to take their guests to places a foreigner may never be able to find on his or her own! This is what I encountered my first weekend in Dakar, Senegal. My three sisters asked me to go with them to Monaco Beach, and though I wasn’t really up to it, I decided that I should accept their offer. Little did I know how much of a growing experience it would be for me.
Kumusha Tales: Messages from Msengezi and Other Stories
Authors: Watkins John J.
Published: August 2021

On January 8, 1998—my birthday, as it happens—I greeted 24 tired and slightly scared undergraduates from the United States as they got off their British Airways flight from London and stood in line awaiting immigration and customs clearance at the airport in Harare. I had taken a semester off from my job as professor of mathematics at Colorado College to direct the ACM (Associated Colleges of the Midwest) Program in Zimbabwe and had no more idea what our joint experience in Zimbabwe would bring than they did. I too was nervous with anticipation.
THE STAGING OF MENANDER'SSIKYONIOI
Authors: Favi Federico
Published: August 2021

The aim of this article is twofold. First, it collects and discusses the evidence that supports A. M. Belardinelli's identification of the speakers in lines 150–271 of Menander'sSikyonioi; her reconstruction can also be strengthened and improved upon in some important details. Further, a re-examination of line 169 allows for a new interpretation of the staging of the play: three stage doors need to be active, and the third stage building is a shrine which Eleusinios enters to take part in the sacrifice.
Wildfires Are Threatening Municipal Water Supplies
Authors: Chow Alex , Karanfil Tanju , Dahlgren Randy
Published: August 2021

Climate change is driving an increase in catastrophic wildfires; consumers see, smell, and taste the effects in their water. Water utilities must prepare for worse times ahead.
Modeling the Viscosity of Anhydrous and Hydrous Volcanic Melts
Authors: Langhammer D. , Di Genova D. , Steinle‐Neumann G.
Published: August 2021

The viscosity of volcanic melts is a dominant factor in controlling the fluid dynamics of magmas and thereby eruption style. It can vary by several orders of magnitude, depending on temperature, chemical composition, and water content. The experimentally accessible temperature range is restricted by melt crystallization and gas exsolution. Therefore, modeling viscosity as a function of temperature and water content is central to physical volcanology. We present a model that describes these dependencies by combining a physically motivated equation for temperature dependence of viscosity and a glass transition temperature () model for the effects of water. The equation uses the viscosity at infinite temperature , , and the steepness factor as fitting parameters. We investigate the effect of leaving free as a parameter and fixing its value, by fitting anhydrous viscosity data of 45 volcanic melts using the temperature dependent model. Both approaches describe experimental data well. Using a constant therefore provides a viable route for extrapolating viscosity from data restricted to small temperature intervals. Our model describes hydrous data over a wide compositional range of terrestrial magmas (26 data sets) with comparable or better quality than literature fits. With constrained, we finally apply our model to viscosities derived by differential scanning calorimetry and find—by comparing to viscometry based data and models—that this approach can be used to reliably describe the dependence of viscosity on temperature and water content. This introduces important implications for modeling the effects of nanostructure formation on viscosity.
Earth's Energy Imbalance From the Ocean Perspective (2005–2019)
Authors: Hakuba M. Z. , Frederikse T. , Landerer F. W.
Published: August 2021

Earth's energy imbalance (EEI) represents the rate of global energy accumulation in response to radiative forcings and feedbacks. Ocean heat uptake (OHU) poses a vital constraint on EEI and its uncertainty. Considering recent geodetic observations, geophysical corrections, and new estimates of the ocean's expansion efficiency of heat, we translate steric sea‐level change, the difference of total sea‐level and ocean‐mass change, into an OHU of 0.86 [0.62, 1.10, 5%–95%] Wm−2 for the period 2005–2019. Adding components of non‐oceanic heat uptake, we obtain an EEI of 0.94 [0.70, 1.19] Wm−2, which is at the upper end of previous assessments, but agrees within uncertainty. Interannual geodetic OHU variability exhibits a higher correlation with top‐of‐the‐atmosphere net radiative flux than hydrographic‐only data, but has a three times larger standard deviation. The radiation fluxes and the geodetic approach suggest an increase in heat uptake since 2005, most markedly in recent years.
Non‐Negligible Contribution to Seasonally Thawing Depth of Active Layer From Extreme Warming Events in the Tanggula Permafrost Region of Qinghai‐Tibet Plateau
Authors: Zhu Xiaofan , Wu Tonghua , Hu Guojie , Ni Jie , Zou Defu , Chen Jie , Li Xiangfei , Wu Xiaodong , Li Ren
Published: August 2021

Despite rising interest in the impacts of long‐term gradual climate warming on permafrost changes, little is known about the changes in active‐layer thermal conditions after transient and abrupt extreme warming events. Here, we investigated the Tanggula permafrost region of the Qinghai‐Tibet Plateau using in situ meteorological and active‐layer hydrothermal data. The results showed that the magnitude of variation in the thermal condition of the active layer was positively correlated with the duration and intensity of extreme warming events. The average contribution rate of extreme warming events to seasonally thawing depth was 13.5% ± 4.9% from April to October, and higher rates occurred in the initial and final stages of the thawing process. The thawing process of the active layer was the main factor controlling the thermal responses of this layer to extreme warming events. Moreover, the interannual differences in active‐layer thermal conditions during the thawing period were likely related to the interannual differences in the frequency and intensity of extreme warming events.
Alien Aeolian Bedforms: A Comparative Sedimentary Analysis of the Dingo Gap Bedform and Hidden Valley Ripple Traverses, Gale Crater, Mars
Authors: Bretzfelder Jordan M. , Day Mackenzie
Published: August 2021

At the end of January 2014 (Sols 528–540), the Mars Science Laboratory rover Curiosity approached the valley opening known as Dingo Gap. Spanning this gap was an unusual bedform with a maximum height of 1.34 m and a maximum width of ∼8 m. Curiosity encountered, imaged, and successfully traversed this atypical bedform. In August of 2014, Curiosity began to traverse a field of ripples in Hidden Valley, but was forced to abort the attempt due to high wheel slip. The Hidden Valley ripples are ∼1/6 of the height of the Dingo Gap bedform, and yet posed a serious hazard to the rover. Here, we present a sedimentological analysis of the Dingo Gap bedform and the Hidden Valley ripples and discuss how their differences may have impacted rover traversability. The Dingo Gap and Hidden Valley bedforms are morphologically similar to many commonly observed bedforms on Mars that have few clear analogs on Earth, and Curiosity's encounters provide a framework for studying these bedforms in detail. Furthermore, the rover tracks across the bedforms have persisted for >5 Earth years, even through a global dust storm. The longevity of the tracks demonstrates that on multi‐year timescales (a) sediment transport on some Martian bedforms is inactive or slow enough that areas disturbed by the rover are not resurfaced, and (b) the rate of dust deposition on the Martian surface, even after a global dust storm, is too low to create an optically thick layer.
Socioeconomic inequalities in the food environment and body composition among school-aged children: a fixed-effects analysis
Authors: Mölenberg Famke J. M. , Mackenbach Joreintje D. , Poelman Maartje P. , Santos Susana , Burdorf Alex , van Lenthe Frank J.
Published: August 2021

Background

There is limited evidence regarding socioeconomic inequalities of exposure to the food environment and its contribution to childhood obesity.

Methods

We used data from 4235 children from the Generation R Study, a large birth-cohort conducted in the city of Rotterdam, The Netherlands. We included 11,277 person-observations of body mass index (BMI) and 6240 person-observations of DXA-derived fat mass index (FMI) and fat-free mass index (FFMI) when children were between 4 and 14 years. We applied linear regression models to evaluate changes in the relative and absolute exposure of fast-food outlets, and the healthiness of the food environment within 400 m from home by maternal education. Furthermore, we used individual-level fixed-effects models to study changes in the food environment to changes in BMI, FMI and FFMI.

Results

Children from lower educated mothers were exposed to more fast-food outlets at any time-point between the age of 4 and 14 years. Over a median period of 7.1 years, the absolute (0.6 fast-food outlet (95% CI: 0.4–0.8)) and relative (2.0%-point (95% CI: 0.7–3.4)) amount of fast-food outlets increased more for children from lower as compared to higher educated mothers. The food environment became more unhealthy over time, but no differences in trends were seen by maternal education level. Changes in the food environment were not associated with subsequent changes in BMI, FMI and FFMI. For children from lower educated mothers not exposed to fast-food at first, we found some evidence that the introduction of fast-food was associated with small increases in BMI.

Conclusions

Our findings provide evidence of widening inequalities in exposure to fast-food in an already poor food environment. Access to more fast-food outlets does not seem to have an additional impact on BMI in contemporary contexts with ubiquitous fast-food outlets.
Acoustofluidic localization of sparse particles on a piezoelectric resonant sensor for nanogram-scale mass measurements
Authors: Qian Jingui , Begum Habiba , Lee Joshua E.-Y.
Published: August 2021

The ability to weigh microsubstances present in low concentrations is an important tool for environmental monitoring and chemical analysis. For instance, developing a rapid analysis platform that identifies the material type of microplastics in seawater would help evaluate the potential toxicity to marine organisms. In this study, we demonstrate the integration of two different techniques that bring together the functions of sparse particle localization and miniaturized mass sensing on a microelectromechanical system (MEMS) chip for enhanced detection and minimization of negative measurements. The droplet sample for analysis is loaded onto the MEMS chip containing a resonant mass sensor. Through the coupling of a surface acoustic wave (SAW) from a SAW transducer into the chip, the initially dispersed microparticles in the droplet are localized over the detection area of the MEMS sensor, which is only 200 µm wide. The accreted mass of the particles is then calibrated against the resulting shift in resonant frequency of the sensor. The SAW device and MEMS chip are detachable after use, allowing the reuse of the SAW device part of the setup instead of the disposal of both parts. Our platform maintains the strengths of noncontact and label-free dual-chip acoustofluidic devices, demonstrating for the first time an integrated microparticle manipulation and real-time mass measurement platform useful for the analysis of sparse microsubstances.
Mapping the biosynthetic pathway of a hybrid polyketide-nonribosomal peptide in a metazoan
Authors: Feng Likui , Gordon Matthew T. , Liu Ying , Basso Kari B. , Butcher Rebecca A.
Published: August 2021

Polyketide synthase (PKS) and nonribosomal peptide synthetase (NRPS) hybrid systems typically use complex protein-protein interactions to facilitate direct transfer of intermediates between these multimodular megaenzymes. In the canal-associated neurons (CANs) of Caenorhabditis elegans, PKS-1 and NRPS-1 produce the nemamides, the only known hybrid polyketide-nonribosomal peptides biosynthesized by animals, through a poorly understood mechanism. Here, we use genome editing and mass spectrometry to map the roles of individual PKS-1 and NRPS-1 enzymatic domains in nemamide biosynthesis. Furthermore, we show that nemamide biosynthesis requires at least five additional enzymes expressed in the CANs that are encoded by genes distributed across the worm genome. We identify the roles of these enzymes and discover a mechanism for trafficking intermediates between a PKS and an NRPS. Specifically, the enzyme PKAL-1 activates an advanced polyketide intermediate as an adenylate and directly loads it onto a carrier protein in NRPS-1. This trafficking mechanism provides a means by which a PKS-NRPS system can expand its biosynthetic potential and is likely important for the regulation of nemamide biosynthesis.
Facile access to C-glycosyl amino acids and peptides via Ni-catalyzed reductive hydroglycosylation of alkynes
Authors: Liu Yan-Hua , Xia Yu-Nong , Gulzar Tayyab , Wei Bingcheng , Li Haotian , Zhu Dapeng , Hu Zhifei , Xu Peng , Yu Biao
Published: August 2021

C-Glycosyl peptides/proteins are metabolically stable mimics of the native glycopeptides/proteins bearing O/N-glycosidic linkages, and are thus of great therapeutical potential. Herein, we disclose a protocol for the syntheses of vinyl C-glycosyl amino acids and peptides, employing a nickel-catalyzed reductive hydroglycosylation reaction of alkyne derivatives of amino acids and peptides with common glycosyl bromides. It accommodates a wide scope of the coupling partners, including complex oligosaccharide and peptide substrates. The resultant vinyl C-glycosyl amino acids and peptides, which bear common O/N-protecting groups, are amenable to further transformations, including elongation of the peptide and saccharide chains.
A transcription-based mechanism for oncogenic β-catenin-induced lethality in BRCA1/2-deficient cells
Authors: Dagg Rebecca A. , Zonderland Gijs , Lombardi Emilia Puig , Rossetti Giacomo G. , Groelly Florian J. , Barroso Sonia , Tacconi Eliana M. C. , Wright Benjamin , Lockstone Helen , Aguilera Andrés , Halazonetis Thanos D. , Tarsounas Madalena
Published: August 2021

BRCA1orBRCA2germline mutations predispose to breast, ovarian and other cancers. High-throughput sequencing of tumour genomes revealed that oncogene amplification andBRCA1/2mutations are mutually exclusive in cancer, however the molecular mechanism underlying this incompatibility remains unknown. Here, we report that activation of β-catenin, an oncogene of the WNT signalling pathway, inhibits proliferation of BRCA1/2-deficient cells. RNA-seq analyses revealed β-catenin-induced discrete transcriptome alterations in BRCA2-deficient cells, including suppression ofCDKN1Agene encoding the CDK inhibitor p21. This accelerates G1/S transition, triggering illegitimate origin firing and DNA damage. In addition, β-catenin activation accelerates replication fork progression in BRCA2-deficient cells, which is critically dependent on p21 downregulation. Importantly, we find that upregulated p21 expression is essential for the survival of BRCA2-deficient cells and tumours. Thus, our work demonstrates that β-catenin toxicity in cancer cells with compromised BRCA1/2 function is driven by transcriptional alterations that cause aberrant replication and inflict DNA damage.
Hyperleptinemia in obese state renders luminal breast cancers refractory to tamoxifen by coordinating a crosstalk between Med1, miR205 and ErbB
Authors: Nagalingam Arumugam , Siddharth Sumit , Parida Sheetal , Muniraj Nethaji , Avtanski Dimiter , Kuppusamy Panjamurthy , Elsey Justin , Arbiser Jack L. , Győrffy Balázs , Sharma Dipali
Published: August 2021

Obese women with hormone receptor-positive breast cancer exhibit poor response to therapy and inferior outcomes. However, the underlying molecular mechanisms by which obesity/hyperleptinemia may reduce the efficacy of hormonal therapy remain elusive. Obese mice with hyperleptinemia exhibit increased tumor progression and respond poorly to tamoxifen compared to non-obese mice. Exogenous leptin abrogates tamoxifen-mediated growth inhibition and potentiates breast tumor growth even in the presence of tamoxifen. Mechanistically, leptin induces nuclear translocation of phosphorylated-ER and increases the expression of ER-responsive genes, while reducing tamoxifen-mediated gene repression by abrogating tamoxifen-induced recruitment of corepressors NCoR, SMRT, and Mi2 and potentiating coactivator binding. Furthermore, in silico analysis revealed that coactivator Med1 potentially associates with 48 (out of 74) obesity-signature genes. Interestingly, leptin upregulates Med1 expression by decreasing miR-205, and increases its functional activation via phosphorylation, which is mediated by activation of Her2 and EGFR. It is important to note that Med1 silencing abrogates the negative effects of leptin on tamoxifen efficacy. In addition, honokiol or adiponectin treatment effectively inhibits leptin-induced Med1 expression and improves tamoxifen efficacy in hyperleptinemic state. These studies uncover the mechanistic insights how obese/hyperleptinemic state may contribute to poor response to tamoxifen implicating leptin-miR205-Med1 and leptin-Her2-EGFR-Med1 axes, and present bioactive compound honokiol and adipocytokine adiponectin as agents that can block leptin’s negative effect on tamoxifen.
Aqueous alteration of silicate glass: state of knowledge and perspectives
Authors: Gin Stéphane , Delaye Jean-Marc , Angeli Frédéric , Schuller Sophie
Published: August 2021

The question of silicate glass chemical durability is at the heart of many industrial and environmental issues, with certain glasses, such as bioglasses, needing to transform rapidly, while others, like nuclear glasses, extremely slowly. Due to the wide diversity of the chemical composition for these types of materials and their metastability—no thermodynamic equilibrium can be reached between glass and solution—the evaluation of chemical durability remains a scientific challenge. In this article, we review the current state of knowledge on glass alteration mechanisms and kinetics, and point to some perspectives for glasses for which no direct experimental validation is currently possible. Thanks to the development of novel techniques and international collaborations, a better understanding of the mechanisms involved has been achieved. Mechanistic models have been developed at some specific scales, although holistic models still need further development to link the various scales and perform reliable predictions.
Tailored synbiotic powder (functional food) to prevent hyperphosphataemia (kidney disorder)
Authors: Anand Ajeeta , Yoshida Shigeki , Aoyagi Hideki
Published: August 2021

Hyperphosphataemia is treated with phosphate binders, which can cause adverse effects. Spray-dried synbiotic powder (SP) composed of Lactobacillus casei JCM1134 (a phosphate-accumulating organism; PAO) and Aloe vera is potentially a safer alternative for efficient phosphate removal. In this study, a novel strategy was developed; lysine-derivatized deacetylated A. vera (DAVK) was synthesised and fabricated on phosphate-deficient PAO (PDP) for efficient phosphate transfer and then spray-dried with the supernatant of DAV centrifugation to form a sacrificial layer on PDP for SP integrity during gastric passage. In vitro experiments revealed that PAO removed only 1.6% of the phosphate from synthetic media, whereas SP removed 89%, 87%, and 67% (w/v) of the phosphate from milk, soft drink, and synthetic media, respectively, confirming the protective role of A. vera and efficient phosphate transport. Compared with commercial binders, SP effectively removed phosphate from synthetic media, whereas SP and CaCO3 exhibited comparative results for milk and soft drink. Importantly, CaCO3 caused hypercalcaemia. Thus, the described SP presents a promising tool to prevent hyperphosphataemia. This study also revealed a novel factor: diets of patients with chronic kidney disease should be monitored to determine the optimal phosphate binders, as phosphate removal performance depends on the accessible phosphate forms.
Strong association of type 2 diabetes with degenerative lumbar spine disorders
Authors: Park Chul-Hyun , Min Kyoung-Bok , Min Jin-Young , Kim Du Hwan , Seo Kyung Mook , Kim Don-Kyu
Published: August 2021

Tantalizing connections between type 2 diabetes and degenerative lumbar spine disorders have become increasingly evident. However, the association of type 2 diabetes with degenerative lumbar spine disorders remains unclear. We sought to clarify the association between type 2 diabetes and lumbar spine disorders using nationwide data in Korea. Furthermore, we explored the association of diabetes with the prevalence of spinal procedures. The data in this study was obtained from Korean health claim database. Between 2016 and 2019, totals of 479,680 diabetes and 479,680 age- and sex-matched control subjects were enrolled. Patients with diabetes had more likely to have degenerative lumbar spine disorders and spinal procedures than controls. Using multivariate-adjusted analysis, patients with diabetes were at increased risk of being concomitantly affected by lumbar disc disorder [adjusted odds ratio 1.11 (95% confidence interval 1.10–1.12)], lumbar spondylotic radiculopathy [1.12 (1.11–1.13)], spondylolisthesis [1.05 (1.02–1.08)] and spinal stenosis [1.16 (1.15–1.18)], compared to controls. Furthermore, diabetic patients had an increased risk of undergoing lumbar spinal injection [1.13 (1.12–1.14)], laminectomy [1.19 (1.15–1.23)], and fusion surgery [1.35 (1.29–1.42)]. We demonstrated that type 2 diabetes was significantly associated with lumbar spine disorders and frequent spinal procedures. Our results suggest diabetes as a predisposing factor for lumbar spine disorders.
Genetic and phenotypic analysis of the pathogenic potential of two novel Chlamydia gallinacea strains compared to Chlamydia psittaci
Authors: Heijne Marloes , Jelocnik Martina , Umanets Alexander , Brouwer Michael S. M. , Dinkla Annemieke , Harders Frank , van Keulen Lucien J. M. , Roest Hendrik Jan , Schaafsma Famke , Velkers Francisca C. , van der Goot Jeanet A. , Pannekoek Yvonne , Koets Ad P.
Published: August 2021

Chlamydia gallinacea is an obligate intracellular bacterium that has recently been added to the family of Chlamydiaceae. C. gallinacea is genetically diverse, widespread in poultry and a suspected cause of pneumonia in slaughterhouse workers. In poultry, C. gallinacea infections appear asymptomatic, but studies about the pathogenic potential are limited. In this study two novel sequence types of C. gallinacea were isolated from apparently healthy chickens. Both isolates (NL_G47 and NL_F725) were closely related to each other and have at least 99.5% DNA sequence identity to C. gallinacea Type strain 08-1274/3. To gain further insight into the pathogenic potential, infection experiments in embryonated chicken eggs and comparative genomics with Chlamydia psittaci were performed. C. psittaci is a ubiquitous zoonotic pathogen of birds and mammals, and infection in poultry can result in severe systemic illness. In experiments with embryonated chicken eggs, C. gallinacea induced mortality was observed, potentially strain dependent, but lower compared to C. psittaci induced mortality. Comparative analyses confirmed all currently available C. gallinacea genomes possess the hallmark genes coding for known and potential virulence factors as found in C. psittaci albeit to a reduced number of orthologues or paralogs. The presence of potential virulence factors and the observed mortality in embryonated eggs indicates C. gallinacea should rather be considered as an opportunistic pathogen than an innocuous commensal.
ICAM-1-carrying targeted nano contrast agent for evaluating inflammatory injury in rabbits with atherosclerosis
Authors: Li Ping , Jin Lin , Feng Lan , Wang Yingchun , Yang Rong
Published: August 2021

To investigate the feasibility of using ICAM-1-targeted nano ultrasonic contrast to evaluate the degree of inflammatory injury at different stages in the abdominal aorta of rabbits with atherosclerosis (AS). Twenty-five experimental rabbits were assigned to five groups: the control group (A); the week-4 after modeling group (B); the week-8 after modeling group (C); the week-12 after modeling group (D); the week-16 after modeling group (E). All groups were given 2D ultrasonography, conventional ultrasonic contrast (SonoVue), and ICAM-1-targeted nano ultrasonic contrast, respectively. Signal intensity of vascular perfusion was evaluated. Signal intensity of ICAM-1-targeted nano ultrasonic contrast was substantially enhanced and prolonged in the vascular wall of the abdominal bubble aorta increased in B, C, D, and E groups (all P < 0.05). A positive linear correlation between intensity and the expression of ICAM-1 (r = 0.895, P < 0.001). The intensity of outer membrane was enhanced from week 4 to week 12, and both the intima-media membrane and outer membrane were enhanced with double-layer parallel echo at week 16, which was in line with the progression of atherosclerotic plaque inflammatory injury. ICAM-1-targeted nano contrast agent would be possibly a novel non-invasive molecular imaging method for plaque inflammatory injury and site high expression of specific adhesion molecules in early atherosclerotic lesions.
Early decompressive hemicraniectomy in thrombolyzed acute ischemic stroke patients from the international ENCHANTED trial
Authors: Xia Chao , Wang Xia , Lindley Richard I. , Delcourt Candice , Chen Xiaoying , Zhou Zien , Guo Rui , Carcel Cheryl , Malavera Alejandra , Calic Zeljka , Mair Grant , Wardlaw Joanna M. , Robinson Thompson G. , Anderson Craig S.
Published: August 2021

Decompressive hemicraniectomy (DHC) can improve outcomes for patients with severe forms of acute ischemic stroke (AIS), but the evidence is mainly derived from non-thrombolyzed patients. We aimed to determine the characteristics and outcomes of early DHC in thrombolyzed AIS participants of the international Enhanced Control of Hypertension and Thrombolysis Stroke Study (ENCHANTED). Post-hoc analyses of ENCHANTED, an international, partial-factorial, open, blinded outcome-assessed, controlled trial in 4557 thrombolysis-eligible AIS patients randomized to low- versus standard-dose intravenous alteplase (Arm A, n = 2350), intensive versus guideline-recommended blood pressure control (Arm B, n = 1280), or both (Arms A + B, n = 947). Logistic regression models were used to identify baseline variables associated with DHC, with inverse probability of treatment weights employed to eliminate baseline imbalances between those with and without DHC. Logistic regression was also used to determine associations of DHC and clinical outcomes of death/disability, major disability, and death (defined by scores 2–6, 3–5, and 6, respectively, on the modified Rankin scale) at 90 days post-randomization. There were 95 (2.1%) thrombolyzed AIS patients who underwent DHC, who were significantly younger, of non-Asian ethnicity, and more likely to have had prior lipid-lowering treatment and severe neurological impairment from large vessel occlusion than other patients. DHC patients were more likely to receive other management interventions and have poor functional outcomes than non-DHC patients, with no relation to different doses of intravenous alteplase. Compared to other thrombolyzed AIS patients, those who received DHC had a poor prognosis from more severe disease despite intensive in-hospital management.
Chemical analysis of the human brain by imaging mass spectrometry
Authors: Ajith Akhila , Sthanikam Yeswanth , Banerjee Shibdas
Published: August 2021

Imaging mass spectrometry enables visualization of the neuroanatomical distribution of thousands of biochemicals in the human brain, providing a wealth of information for diagnostic, prognostic, and therapeutic developments for neuro diseases.
Quantification of molecular weight discrimination in grafting to reactions from ultrathin polymer films by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry
Authors: Chiarcos Riccardo , Antonioli Diego , Ospina Viviana , Laus Michele , Perego Michele , Gianotti Valentina
Published: August 2021

A reliable and robust method was developed to quantify the molecular weight discrimination that can occur in grafting to reactions via indirect MALDI-TOF quantification of the molecular weights of grafted chains.
Hydrolysis of methylphosphonic anhydride solid to methylphosphonic acid probed by Raman and infrared reflectance spectroscopies
Authors: Myers Tanya L. , Saunders Danielle L. , Szecsody James E. , Tonkyn Russell G. , Mo Kai-For , Cappello Benjamin F. , Banach Catherine A. , Fraga Carlos G. , Johnson Timothy J.
Published: August 2021

Much is still unknown about the mechanisms and rates of environmental degradation of organophosphorous pesticides and agents.
Aptamer–gold nanoparticle-signal probe bioconjugates amplify electrochemical signal for the detection of prostate specific antigen
Authors: Li Mengyao , Zhang Wenjuan , Zhang Yuzhong
Published: August 2021

A simple and sensitive electrochemical immunosensor for the detection of PSA was reported.
Recent advancements in the detection of organophosphate pesticides: a review
Authors: Bhattu Monika , Verma Meenakshi , Kathuria Deepika
Published: August 2021

The colorimetric, fluorescence and electrochemical methods, working principles and the limit of detection of organophosphorus pesticides have been discussed from the period 2015–2021.
Delivery of miR-320a-3p by gold nanoparticles combined with photothermal therapy for directly targeting Sp1 in lung cancer
Authors: Peng Jiefei , Wang Ranran , Sun Wanru , Huang Minhua , Wang Rong , Li Youjie , Wang Pingyu , Sun Guangbin , Xie Shuyang
Published: August 2021

A new and promising anticancer strategy via the use of Au-RGD-miR-320a nanoparticles, and identify miR-320a/Sp1 as a potential target for future systemic therapy against lung cancer.
NIR emissive light-harvesting systems through perovskite passivation and sequential energy transfer for third-level fingerprint imaging
Authors: Zhong Kaipeng , Lu Siyu , Guo Wenting , Su Junxia , Sun Shihao , Hai Jun , Wang Baodui
Published: August 2021

An efficient perovskite quantum dot light-harvesting system with NIR emission was fabricated for NIR fluorescence imaging of sweat pores in fingerprints.
Inducing molecular reactions by selective vibrational excitation of a remote antenna with near-infrared light
Authors: M. Nunes Cláudio , Pereira Nelson A. M. , Viegas Luís P. , Pinho e Melo Teresa M. V. D. , Fausto Rui
Published: August 2021

Ring-expansion of a benzazirine by IR-light tuned at the overtone stretching frequency of its OH remote antenna. Proof-of-principle demonstration for harnessing the power of IR vibrational excitation to guide reactions in unprecedented selective way.
Covalent photofunctionalization and electronic repair of 2H-MoS2via nitrogen incorporation
Authors: Osthues Helena , Schwermann Christian , Preuß Johann A. , Deilmann Thorsten , Bratschitsch Rudolf , Rohlfing Michael , Doltsinis Nikos L.
Published: August 2021

Ab initio calculations are used to study defect-free attachment of functional molecules via nitrogen incorporation at sulfur vacancies. This approach allows for stable modification while keeping the extraordinary properties of MoS2 monolayers.
Unveiling the effect of the crystalline phases of iron oxyhydroxide for highly sensitive and selective detection of dopamine
Authors: Moolayadukkam Sreejesh , Vishwanathan Savithri , Jun Byeongsun , Lee Sang Uck , Matte H. S. S. Ramakrishna
Published: August 2021

Electrochemical dopamine sensors: The impact of different crystalline phases (α-, β-, and γ-) of iron oxyhydroxide (FeOOH) on its dopamine sensing ability has been explored through experimental and theoretical studies.
Chemical reduction of Ag+ to Ag employing organic electron donors: evaluation of the effect of Ag+-mediated cytosine–cytosine base pairing on the aggregation of Ag nanoparticles
Authors: Dairaku Takenori , Kawai Rika , Nozawa-Kumada Kanako , Yoshida Kentaro , Ono Tetsuya , Kondo Yoshinori , Kondo Jiro , Ono Akira , Tanaka Yoshiyuki , Kashiwagi Yoshitomo
Published: August 2021

The formation of C–Ag+–C base pairing inhibits the aggregation of AgNPs in solution. The total concentration of the obtained AgNP solution can be controlled by the degree of the reduction activity of the organic electron donors.
Approaching a high-rate and sustainable production of hydrogen peroxide: oxygen reduction on Co–N–C single-atom electrocatalysts in simulated seawater
Authors: Zhao Qinglan , Wang Yian , Lai Wei-Hong , Xiao Fei , Lyu Yuxiang , Liao Caizhi , Shao Minhua
Published: August 2021

Sustainable production of H2O2 is boosted by oxygen reduction reaction on Co–N5 sites in a flow cell in simulated seawater.
A glucose tolerant β-glucosidase from Thermomicrobium roseum that can hydrolyze biomass in seawater
Authors: Sinha Sushant K. , Datta Maithili , Datta Supratim
Published: August 2021

A β-Glucosidase B9L147 from Thermomicrobium roseum can tolerate high concentration of glucose, ionic liquids, salts and metal ions and can hydrolyse substrate in seawater.
Phthalimide analogs for antimalarial drug discovery
Authors: Bansal Meenakshi , Upadhyay Charu , Poonam  , Kumar Sumit , Rathi Brijesh
Published: August 2021

Potent phthalimide-based antiplasmodial compounds are active at different stages of the Plasmodium falciparum life cycle.
All-optical tunable slow-light based on an analogue of electromagnetically induced transparency in a hybrid metamaterial
Authors: Ma Chengju , Zhang Yuebin , Zhang Yao , Bao Shiqian , Jin Jiasheng , Li Mi , Li Dongming , Liu Yinggang , Xu Yiping
Published: August 2021

Based on an analogue of EIT in a proposed hybrid metamaterial, we theoretically demonstrate an all-optical tunable slow-light effect, and show the possibility of designing novel all-optical tunable chip-scale slow-light devices.
Quantitative activity–activity relationship (QAAR) driven design to develop hydroxamate derivatives of pentanoic acids as selective HDAC8 inhibitors: synthesis, biological evaluation and binding mode of interaction studies
Authors: Amin Sk. Abdul , Trivedi Prakruti , Adhikari Nilanjan , Routholla Ganesh , Vijayasarathi Dhanya , Das Sanjib , Ghosh Balaram , Jha Tarun
Published: August 2021

Histone deacetylase 8 (HDAC8) has been implicated as a potential drug target of many diseases including cancer.
A serendipitous self-assembly synthesis of CNN–Pt pincer complexes
Authors: Sánchez-Pérez Eva , Santos-Escobar Fernando , Gutiérrez-Corona J. Félix , Wrobel Kazimierz , Wrobel Katarzyna , Serrano Oracio
Published: August 2021

A serendipitous one pot self-assembly synthesis of hydride CNN–Pt(iv) pincer complexes was achieved, which involves a formal C–H bond activation, with an earlier C–N bond formation via C–Br bond excision, instead of the expected rollover complex.
A novel fluorescent probe for the detection of sulfur dioxide derivatives and its application in biological imaging
Authors: Yang Qing-Qing , Tian Qin-Qin , Ji Nan , Duan Xiao-Hong , Zhu Xiao-Hong , Zhang Yan-Li , He Wei
Published: August 2021

A new probe CA-SO2 to efficiently and specifically detect SO2 was designed. The probe showed a fast response time (<50 s), low detection limit (LOD = 75 nM), large Stokes shift (129 nm) and was applied to detect SO2 in living cells and zebrafish.
Enantioselective vinylogous aldol reaction of acylphosphonates with 3-alkylidene oxindoles
Authors: Jaiswal Manish K. , Singh Sanjay , Singh Ravi P.
Published: August 2021

A simple strategy for yielding chiral tertiary α-hydroxy phosphonates that integrates two highly biologically relevant scaffolds namely 3-alkylidene-2-oxindoles and phosphonates has been described.
A new tunnel-type V4O9 cathode for high power density aqueous zinc ion batteries
Authors: Wang Qiaoran , Sun Tianjiang , Zheng Shibing , Li Lin , Ma Tao , Liang Jing
Published: August 2021

A mixed-valence vanadium oxide V4O9 with a tunnel structure was synthesized as a cathode material for aqueous zinc ion batteries. A Zn//V4O9 battery displays high specific capacity and excellent rate performance.