bluuebunny/crossref_metadata_2025 huggingface dataset:
Activation of neutral sphingomyelinase 2 through hyperglycemia contributes to endothelial apoptosis via vesicle-bound intercellular transfer of ceramides
Authors: Zietzer Andreas , Jahnel Alina Lisann , Bulic Marko , Gutbrod Katharina , Düsing Philip , Hosen Mohammed Rabiul , Dörmann Peter , Werner Nikos , Nickenig Georg , Jansen Felix
Published: December 2021

Background

Pro-apoptotic and pro-inflammatory ceramides are crucially involved in atherosclerotic plaque development. Local cellular ceramide accumulation mediates endothelial apoptosis, especially in type 2 diabetes mellitus, which is a major cardiovascular risk factor. In recent years, large extracellular vesicles (lEVs) have been identified as an important means of intercellular communication and as regulators of cardiovascular health and disease. A potential role for lEVs as vehicles for ceramide transfer and inductors of diabetes-associated endothelial apoptosis has never been investigated.

Methods and Results

A mass-spectrometric analysis of human coronary artery endothelial cells (HCAECs) and their lEVs revealed C16 ceramide (d18:1–16:0) to be the most abundant ceramide in lEVs and to be significantly increased in lEVs after hyperglycemic injury to HCAECs. The increased packaging of ceramide into lEVs after hyperglycemic injury was shown to be dependent on neutral sphingomyelinase 2 (nSMase2), which was upregulated in glucose-treated HCAECs. lEVs from hyperglycemic HCAECs induced apoptosis in the recipient HCAECs compared to native lEVs from untreated HCAECs. Similarly, lEVs from hyperglycemic mice after streptozotocin injection induced higher rates of apoptosis in murine endothelial cells compared to lEVs from normoglycemic mice. To generate lEVs with high levels of C16 ceramide, ceramide was applied exogenously and shown to be effectively packaged into the lEVs, which then induced apoptosis in lEV-recipient HCAECs via activation of caspase 3. Intercellular transfer of ceramide through lEVs was confirmed by use of a fluorescently labeled ceramide analogue. Treatment of HCAECs with a pharmacological inhibitor of nSMases (GW4869) or siRNA-mediated downregulation of nSMase2 abrogated the glucose-mediated effect on apoptosis in lEV-recipient cells. In contrast, for small EVs (sEVs), hyperglycemic injury or GW4869 treatment had no effect on apoptosis induction in sEV-recipient cells.

Conclusion

lEVs mediate the induction of apoptosis in endothelial cells in response to hyperglycemic injury through intercellular transfer of ceramides.

Graphical abstract
Targeted deletion of keratin 8 in intestinal epithelial cells disrupts tissue integrity and predisposes to tumorigenesis in the colon
Authors: Stenvall Carl-Gustaf A. , Tayyab Mina , Grönroos Tove J. , Ilomäki Maria A. , Viiri Keijo , Ridge Karen M. , Polari Lauri , Toivola Diana M.
Published: December 2021

Keratin 8 (K8) is the main intestinal epithelial intermediate filament protein with proposed roles for colonic epithelial cell integrity. Here, we used mice lacking K8 in intestinal epithelial cells (floxed K8 and Villin-Cre1000 and Villin-CreERt2) to investigate the cell-specific roles of intestinal epithelial K8 for colonocyte function and pathologies. Intestinal epithelial K8 deletion decreased K8 partner proteins, K18–K20, 75–95%, and the remaining keratin filaments were located at the colonocyte apical regions with type II K7, which decreased 30%. 2-Deoxy-2-[18F]-fluoroglucose positron emission tomography in vivo imaging identified a metabolic phenotype in the lower gut of the conditional K8 knockouts. These mice developed intestinal barrier leakiness, mild diarrhea, and epithelial damage, especially in the proximal colon. Mice exhibited shifted differentiation from enterocytes to goblet cells, displayed longer crypts and an increased number of Ki67 + transit-amplifying cells in the colon. Significant proproliferative and regenerative signaling occurred in the IL-22, STAT3, and pRb pathways, with minor effects on inflammatory parameters, which, however, increased in aging mice. Importantly, colonocyte K8 deletion induced a dramatically increased sensitivity to azoxymethane-induced tumorigenesis. In conclusion, intestinal epithelial K8 plays a significant role in colonocyte epithelial integrity maintenance, proliferation regulation and tumor suppression.

Graphical abstract
A minimally invasive cerclage of the tibia in a modified Goetze technique: operative technique and first clinical results
Authors: Förch Stefan , Reuter Jan , von der Helm Franziska , Lisitano Leonard , Hartwig Christopher , Sandriesser Sabrina , Nuber Stefan , Mayr Edgar
Published: December 2021

Introduction

In spiral fractures of the tibia, the stability of an osteosynthesis may be significantly increased by additive cerclages and, according to biomechanical studies, be brought into a state that allows immediate full weight bearing. As early as 1933, Goetze described a minimally invasive technique for classic steel cerclages. This technique was modified, so that it can be used for modern cable cerclages in a soft part saving way.

Method

After closed reduction, an 8 Fr redon drain is first inserted in a minimally invasive manner, strictly along the bone and placed around the tibia via 1 cm incisions on the anterolateral and dorsomedial tibial edges using a curette and a tissue protection sleeve.

Via this drain, a 1.7 mm cable cerclage can be inserted. The fracture is then anatomically reduced while simultaneously tightening the cerclage. Subsequently, a nail or a minimally invasive plate osteosynthesis is executed using the standard technique.

Using the hospital documentation system, data of patients that were treated with additional cerclages for tibial fractures between 01/01/2014 and 06/30/2020 were subjected to a retrospective analysis for postoperative complications (wound-healing problems, infections and neurovascular injury). Inclusion criteria were: operatively treated tibial fractures, at least one minimally invasive additive cerclage, and age of 18 years or older. Exclusion criteria were: periprosthetic or pathological fractures and the primary need of reconstructive plastic surgery. SPSS was used for statistical analysis.

Results

96 tibial shaft spiral fractures were treated with a total of 113 additive cerclages. The foregoing resulted in 10 (10.4%) postoperative wound infections, 7 of which did not involve the cerclage. One lesion of the profundal peroneal nerve was detected, which largely declined after cerclage removal. In 3 cases, local irritation from the cerclage occurred and required removal of material.

Conclusion

In the described technique, cerclages may be inserted additively at the tibia in a minimally invasive manner and with a few complications, thus significantly increasing the stability of an osteosynthesis. How this ultimately affects fracture healing is the subject of an ongoing study.
Trends in inpatient care for psychiatric disorders in NHS hospitals across England, 1998/99–2019/20: an observational time series analysis
Authors: Degli Esposti Michelle , Ziauddeen Hisham , Bowes Lucy , Reeves Aaron , Chekroud Adam M. , Humphreys David K. , Ford Tamsin
Published: December 2021

Purpose

It is unclear how hospitals are responding to the mental health needs of the population in England, against a backdrop of diminishing resources. We aimed to document patterns in hospital activity by psychiatric disorder and how these have changed over the last 22 years.

Methods

In this observational time series analysis, we used routinely collected data on all NHS hospitals in England from 1998/99 to 2019/20. Trends in hospital admissions and bed days for psychiatric disorders were smoothed using negative binomial regression models with year as the exposure and rates (per 1000 person-years) as the outcome. When linear trends were not appropriate, we fitted segmented negative binomial regression models with one change-point. We stratified by gender and age group [children (0–14 years); adults (15 years +)].

Results

Hospital admission rates and bed days for all psychiatric disorders decreased by 28.4 and 38.3%, respectively. Trends were not uniform across psychiatric disorders or age groups. Admission rates mainly decreased over time, except for anxiety and eating disorders which doubled over the 22-year period, significantly increasing by 2.9% (AAPC = 2.88; 95% CI: 2.61–3.16; p < 0.001) and 3.4% (AAPC = 3.44; 95% CI: 3.04–3.85; p < 0.001) each year. Inpatient hospital activity among children showed more increasing and pronounced trends than adults, including an increase of 212.9% for depression, despite a 63.8% reduction for adults with depression during the same period.

Conclusion

In the last 22 years, there have been overall reductions in hospital activity for psychiatric disorders. However, some disorders showed pronounced increases, pointing to areas of growing need for inpatient psychiatric care, especially among children.
QCM-based assay designs for human serum albumin
Authors: Sudjarwo Wisnu Arfian A. , Dobler Mathias Thomas , Lieberzeit Peter A.
Published: December 2021

Solid-phase synthesis is an elegant way to create molecularly imprinted polymer nanoparticles (nano-MIPs) comprising a single binding site, i.e. mimics of antibodies. When using human serum albumin (HSA) as the template, one achieves nano-MIPs with 53 ± 19 nm diameter, while non-imprinted polymer nanoparticles (nano-NIPs) reach 191 ± 96 nm. Fluorescence assays lead to Stern–Volmer plots revealing selective binding to HSA with selectivity factors of 1.2 compared to bovine serum albumin (BSA), 1.9 for lysozyme, and 4.1 for pepsin. Direct quartz crystal microbalance (QCM) assays confirm these results: nano-MIPs bind to HSA immobilized on QCM surfaces. This opens the way for competitive QCM-based assays for HSA: adding HSA to nanoparticle solutions indeed reduces binding to the QCM surfaces in a concentration-dependent manner. They achieve a limit of detection (LoD) of 80 nM and a limit of quantification (LoQ) of 244 nM. Furthermore, the assay shows recovery rates around 100% for HSA even in the presence of competing analytes.
A cross-scanner and cross-tracer deep learning method for the recovery of standard-dose imaging quality from low-dose PET
Authors: Xue Song , Guo Rui , Bohn Karl Peter , Matzke Jared , Viscione Marco , Alberts Ian , Meng Hongping , Sun Chenwei , Zhang Miao , Zhang Min , Sznitman Raphael , El Fakhri Georges , Rominger Axel , Li Biao , Shi Kuangyu
Published: December 2021

Abstract

Purpose

A critical bottleneck for the credibility of artificial intelligence (AI) is replicating the results in the diversity of clinical practice. We aimed to develop an AI that can be independently applied to recover high-quality imaging from low-dose scans on different scanners and tracers.

Methods

Brain [18F]FDG PET imaging of 237 patients scanned with one scanner was used for the development of AI technology. The developed algorithm was then tested on [18F]FDG PET images of 45 patients scanned with three different scanners, [18F]FET PET images of 18 patients scanned with two different scanners, as well as [18F]Florbetapir images of 10 patients. A conditional generative adversarial network (GAN) was customized for cross-scanner and cross-tracer optimization. Three nuclear medicine physicians independently assessed the utility of the results in a clinical setting.

Results

The improvement achieved by AI recovery significantly correlated with the baseline image quality indicated by structural similarity index measurement (SSIM) (r = −0.71, p < 0.05) and normalized dose acquisition (r = −0.60, p < 0.05). Our cross-scanner and cross-tracer AI methodology showed utility based on both physical and clinical image assessment (p < 0.05).

Conclusion

The deep learning development for extensible application on unknown scanners and tracers may improve the trustworthiness and clinical acceptability of AI-based dose reduction.
[177Lu]Lu-DOTA-TATE versus standard of care in adult patients with gastro-enteropancreatic neuroendocrine tumours (GEP-NETs): a cost-consequence analysis from an Italian hospital perspective
Authors: Spada Francesca , Campana Davide , Lamberti Giuseppe , Laudicella Riccardo , Dellamano Renato , Dellamano Luca , Leeuwenkamp Oscar , Baldari Sergio
Published: December 2021

Purpose

To assess and compare clinical outcomes and costs, to the Italian healthcare system, of three therapeutic options approved in the management of adult patients with gastro-enteropancreatic neuroendocrine tumours (GEP-NETs).

Methods

We compared the efficacy, safety, and costs of [177Lu]Lu-DOTA-TATE, everolimus (both originator and generic products), and sunitinib in patients with advanced GEP-NETs (NET G1 and G2) that had progressed following treatment with somatostatin analogs (SSAs). A cost-consequence model was developed and validated by a panel of clinical experts from three NET reference centres in Italy. The clinical outcomes included in the model were median progression-free survival and the incidence of grade 3 or 4 adverse events (AEs), as reported in pivotal clinical trials. The costs for acquisition and administration of each treatment, and of managing AEs, were calculated from the perspective of the Italian national health service. Treatment costs per progression-free month were calculated separately for patients with NETs of pancreatic (PanNETs; all three treatments) and gastrointestinal (GI-NETs; [177Lu]Lu-DOTA-TATE and everolimus only) origin.

Results

In patients with PanNETs, total costs per progression-free month were €2989 for [177Lu]Lu-DOTA-TATE, €4975 for originator everolimus, €3472 for generic everolimus, and €5337 for sunitinib. In patients with GI-NETs, total costs per progression-free month were €3189 for [177Lu]Lu-DOTA-TATE, €4990 for originator everolimus, and €3483 for generic everolimus.

Conclusions

[177Lu]Lu-DOTA-TATE was associated with lower costs per progression-free month versus relevant treatment options in patients with GI-NETs or PanNETs (NET G1–G2; progressed following SSA treatment), although acquisition and administration costs are higher. These findings provide further economic arguments in the overall context of treatment decision-making.
Impact of oral lipid and glucose tolerance tests on the postprandial concentrations of angiopoietin-like proteins (Angptl) 3 and 4
Authors: Schmid Andreas , Belikan Hannah , Höpfinger Alexandra , Schäffler Andreas , Karrasch Thomas
Published: December 2021

Background

The postprandial regulation of angiopoietin-like proteins (Angptls) and their expression in adipocytes is poorly characterized.

Objective

Circulating Angptl3 and 4 were analyzed in healthy individuals undergoing either an oral lipid tolerance test (OLTT; n = 98) or an oral glucose tolerance test (OGTT; n = 99). Venous blood was drawn after 0, 2, 4, and 6 h during OLTT and after 0, 1, and 2 h during OGTT. Anthropometric and laboratory parameters were assessed and concentrations of Angptls were quantified by enzyme-linked immunosorbent assay. Angptl gene expression in 3T3-L1 adipocytes and in murine adipose tissues and cellular fractions was analyzed by quantitative real-time PCR.

Results

Angptl3 concentrations significantly decreased while Angptl4 levels continuously increased during OLTT. Both proteins remained unaffected during OGTT. Angptl3 and Angptl4 were expressed in murine subcutaneous and visceral AT with higher mRNA levels in mature adipocytes when compared to the stroma-vascular cell fraction. Both proteins were strongly induced during 3T3-L1 adipocyte differentiation and they were unresponsive to glucose in mature fat cells. Adipocyte Angptl3 (but not Angptl4) mRNA expression was inhibited by the polyunsaturated fatty acids arachidonic acid and docosahexaenoic acid, whereas nine types of dietary fatty acids remained without any effect.

Conclusions

There is evidence of short-time regulation of Angptl3/4 levels upon metabolic stress. Angptl4 expression is high and Angptl3 expression is low in AT and restricted mainly to mature adipocytes without any differences concerning fat compartments. Whereas dietary fatty acids and glucose are without any effect, omega-3/-6-polyunsaturated fatty acids inhibited Anptl3 expression in adipocytes.
Seeking Horses: Allies, Clients and Exchanges in the Zhou Period (1045–221 BC)
Authors: Rawson Jessica , Huan Limin , Taylor William Timothy Treal
Published: December 2021

Horses and chariots—and the associated technology and expertise—derived from the steppe contributed to the success of the Zhou conquest of the Shang in c. 1045 BC and remained important throughout Zhou rule in ancient China. On the basis of material cultural patterns, including the style and material used in bridle cheek-pieces found in tombs of the late second and early first millennium BC, this paper points to a northern origin for Zhou horses. Important intermediaries, providing these horses, were the clans whose cemeteries have been identified on the northern edges of the Central Plains. The necessity for repeated exchanges bringing south horses from the north was a consequence of key environmental differences between the steppe and the Central Plains, including climate, geomorphology, essential soil nutrients, and land use. These created significant difficulties in sustainably breeding and pasturing horses of quality. As a result, the people of the Central Plains were bound, over millennia, to seek horses from the northwest, along a cultural corridor that also moved northern materials and technologies, such as gold-, iron- and some bronze-working, into the Central Plains from the steppes.
Identification of key gene networks controlling vernalization development characteristics of Isatis indigotica by full-length transcriptomes and gene expression profiles
Authors: Wang Pan , Liu Dong , Yang Fu-Hong , Ge Hui , Zhao Xin , Chen Hong-Gang , Du Tao
Published: December 2021

Isatis indigotica Fort., as a common Chinese medicinal raw material, will lose its medicinal value if it blooms early, so it is highly valuable to clarify the induction mechanism of the vernalization of I. indigotica at low temperature. In this study, the concentrations of soluble sugar, proline, glutathione and zeatin in two germplasms of I. indigotica with different degrees of low temperature tolerance (Y1 and Y2) were determined at 10 days, 20 days and 30 days of low-temperature treatment, and the full-length transcriptome of 24 samples was sequenced by Nanopore sequencing with Oxford Nanopore Technologies (ONT). After that, the data of transcripts involved in the vernalization of I. indigotica at low temperature were obtained, and these transcripts were identified using weighted gene co-expression network analysis (WGCNA). The results revealed the massive accumulation of soluble sugar and proline in Y1 and Y2 after low temperature induction. A total of 18,385 new transcripts, 6168 transcription factors and 470 lncRNAs were obtained. Differential expression analysis showed that gibberellin, flavonoids, fatty acids and some processes related to low temperature response were significantly enriched. Eight key transcripts were identified by WGCNA, among which ONT.14640.1, ONT.9119.1, ONT.13080.2 and ONT.16007.1 encodes a flavonoid transporter, 9-cis-epoxycarotenoid dioxygenase 3 (NCED3), growth factor gene and L-aspartate oxidase in plants, respectively. It indicated that secondary metabolites such as hormones and flavonoids play an important role in the vernalization of I. indigotica. qRT-PCR proved the reliability of transcriptome results. These results provide important insights on the low-temperature vernalization of I. indigotica, and provide a research basis for analyzing the vernalization mechanism of I. indigotica.
Defect engineering of BCZT-based piezoelectric ceramics with high piezoelectric properties
Authors: Wang Xinjian , Huan Yu , Zhu Yixuan , Zhang Peng , Yang Wenlong , Li Peng , Wei Tao , Li Longtu , Wang Xiaohui
Published: December 2021

The intrinsic conduction mechanism and optimal sintering atmosphere of (Ba0.85Ca0.15)(Zr0.1Ti0.9)O3 (BCZT) ceramics were regulated by Mn-doping element in this work. By Hall and impedance analysis, the undoped BCZT ceramics exhibit a typical n-type conduction mechanism, and the electron concentration decreases with the increasing oxygen partial pressure. Therefore, the undoped ceramics exhibit best electrical properties (piezoelectrical constant d33 = 585 pC·N−1, electro-mechanical coupling factor kp = 56%) in O2. A handful of Mn-doping element would transfer the conduction mechanism from n-type into p-type. And the hole concentration reduces with the decreasing oxygen partial pressure for Mn-doped BCZT ceramics. Therefore, the Mn-doped ceramics sintered in N2 have the highest insulation resistance and best piezoelectric properties (d33 = 505 pC·N−1, kp = 50%). The experimental results demonstrate that the Mn-doping element can effectively adjust the intrinsic conduction mechanism and then predict the optimal atmosphere.
Effect of Vaginal Stretching and Photobiomodulation Therapy on Sexual Function in Women with Pelvic Floor Myofascial Pain - A Randomized Clinical Trial
Authors: Frederice Claudia Pignatti , de Mira Ticiana Aparecida Alves , Machado Helymar Costa , Brito Luiz Gustavo Oliveira , Juliato Cássia R.T.
Published: December 2021

Background

Spasm or increased tonus of the pelvic floor muscles (PFM) can cause myofascial pain (MP), which may result in painful intercourse and sexual dysfunction.

Aim

The effect of vaginal stretching (VS) with photobiomodulation therapy (PBMT) is compared to VS with sham PBMT in overall sexual function, rate and severity of painful intercourse at baseline and after treatment in women with pelvic floor MP.

Methods

A double-blind randomized clinical trial of 103 women with MP: 1 group received 10 sessions of VS with PBMT (4 Joules of near-infrared light-808 nm at 3 points), and the other group received VS with sham PBMT.

Outcomes

Impact of treatment was measured by the number of women experiencing painful intercourse, Pain severity was measured by Visual Analog Scale and sexual function was assessed by the FSFI questionnaire. Variables were assessed at baseline and after ten sessions in the intervention groups.

Results

After treatment, the number of women experiencing painful intercourse was significantly lower in both the VS with PBMT group (90.2–55%, P = .001), and VS with sham PBMT group (86.6–46.2%, P < .001). There was a significant reduction in pain measure by Visual Analog Scale (P < .001, [VS with PBMT group: P = .002; VS with sham PBMT group: P < .001]). There was a significant decrease in the number of participants with sexual dysfunction (FSFI score ≤26.55) after the treatment in the VS with PBMT group (92.2–74.5%, P = .003) and in the VS with sham PBMT group (90.4–76.9%, P = .035). Both groups showed improvement in the FSFI pain domain after treatment (P < .001, [VS with PBMT group: P = .038; VS with sham PBMT group: P = .005]). Only the VS with sham PBMT group had a significant increase in FSFI desire and total score (P < .001) after treatment.

Clinical Implications

We found that VS associated or not with PBMT may be effective in reducing complaints of painful intercourse, alleviating pain severity, and reducing the number of women with pelvic floor MP suffering from sexual dysfunction.

Strengths & Limitations

Strengths of this study are the randomized design and use of validated questionnaires. Limitation of the study is the lack of a long follow-up period and the lack of a usual care comparison group hampers generalizability of the results.

Conclusion

VS only and VS with PBMT have short-term efficacy in reducing painful intercourse and reducing a number of women with sexual dysfunction.
The Power of the People
Authors: Metinsoy Murat
Published: December 2021

Following the collapse of the Ottoman Empire and the founding of the Republic in 1923 under the rule of Atatürk and his Republican People's Party, Turkey embarked on extensive social, economic, cultural and administrative modernization programs which would lay the foundations for modern day Turkey. The Power of the People shows that the ordinary people shaped the social and political change of Turkey as much as Atatürk's strong spurt of modernization. Adopting a broader conception of politics, focusing on daily interactions between the state and society and using untapped archival sources, Murat Metinsoy reveals how rural and urban people coped with the state policies, local oppression, exploitation, and adverse conditions wrought by the Great Depression through diverse everyday survival and resistance strategies. Showing how the people's daily practices and beliefs survived and outweighed the modernizing elite's projects, this book gives new insights into the social and historical origins of Turkey's backslide to conservative and Islamist politics, demonstrating that the making of modern Turkey was an outcome of intersection between the modernization and the people's responses to it.
The Aura of Confucius
Authors: Murray Julia K.
Published: December 2021

The Aura of Confucius is a ground-breaking study that reconstructs the remarkable history of Kongzhai, a shrine founded on the belief that Confucius' descendants buried the sage's robe and cap a millennium after his death and far from his home in Qufu, Shandong. Improbably located on the outskirts of modern Shanghai, Kongzhai featured architecture, visual images, and physical artifacts that created a 'Little Queli,' a surrogate for the temple, cemetery, and Kong descendants' mansion in Qufu. Centered on the Tomb of the Robe and Cap, with a Sage Hall noteworthy for displaying sculptural icons and not just inscribed tablets, Kongzhai attracted scholarly pilgrims who came to experience Confucius's beneficent aura. Although Kongzhai gained recognition from the Kangxi emperor, its fortunes  declined with modernization, and it was finally destroyed during the Cultural Revolution. Unlike other sites, Kongzhai has not been rebuilt and its history is officially forgotten, despite the Confucian revival in contemporary China.
Purity and Pollution in the Hebrew Bible
Authors: Feder Yitzhaq
Published: December 2021

In this book, Yitzhaq Feder presents a novel and compelling account of pollution in ancient Israel, from its emergence as an embodied concept, rooted in physiological experience, to its expression as a pervasive metaphor in social-moral discourse. Feder aims to bring the biblical and ancient Near Eastern evidence into a sustained conversation with anthropological and psychological research through comparison with notions of contagion in other ancient and modern cultural contexts. Showing how numerous interpretive difficulties are the result of imposing modern concepts on the ancient texts, he guides readers through wide-ranging parallels to biblical attitudes in ancient Near Eastern, ethnographic, and modern cultures. Feder demonstrates how contemporary evolutionary and psychological research can be applied to ancient textual evidence. He also suggests a path of synthesis that can move beyond the polarized positions which currently characterize modern academic and popular debates bearing on the roles of biology and culture in shaping human behavior.
Seismic and Electrical Geophysical Characterization of an Incipient Coastal Open‐System Pingo: Lagoon Pingo, Svalbard
Authors: Hammock Craig P. , Kulessa Bernd , Hiemstra John F. , Hodson Andrew J. , Hubbard Alun
Published: December 2021

Whilst there has been a recent appreciation for the role of open‐system pingos in providing a fluid‐flow conduit through continuous permafrost that enables methane release, the formation and internal structure of these ubiquitous permafrost‐diagnostic landforms remains unclear. Here, we combine active‐source seismic measurements with electrical resistivity tomography to investigate the structural and subsurface characteristics of an incipient open‐system pingo actively emitting methane within the glacio‐isostatically uplifting fjord valley of Adventdalen, Svalbard. Wavefront inversion of seismic refractions delineate a spatially heterogeneous active layer, whilst deeper reflections identify the lithological boundaries between marine sediments and underlying shales at ∼68 m depth (p‐wave velocity of ∼1,790 ms−1). Low geometric mean inverted resistivities of 40–150 Ωm highlight the dominance of saline permafrost, whilst elevated resistivities (∼2 kΩm) occur close to the groundwater spring and in heaved areas around the pingo. Based on our results, we speculate that segregation ice dominates the pingo structure, given the absence of a notable resistivity contrast characteristic of injection ice that is typically expected within early open‐system pingo formation, and provides the most plausible geomorphic agent within the local fine‐grained sedimentology. Our results thereby indicate that sediment grain size and moisture availability can provide important controls on pingo formation. This study shows that open‐system pingos in coastal, saline permafrost environments may form differently, with implications for localized permafrost structure, its permeability to underlying gas reservoirs and consequent methane release.
The Perspective from Space Unlocks the Amazon Water Cycle
Authors: Sidder Aaron
Published: December 2021

Satellite imaging and remote sensing offer unique insights into the Amazon’s complex hydrology. A new review summarizes decades of findings and charts a path forward for new remote sensing missions.
A New Tectonic Model Between the Madagascar Ridge and Del Cano Rise in the Indian Ocean
Authors: Sato Taichi , Nogi Yoshifumi , Sato Hiroshi , Fujii Masakazu
Published: December 2021

The southern Indian Ocean has several prominent aseismic ridges recognized as oceanic large igneous provinces (i.e., the Madagascar Ridge, Del Cano Rise, Crozet Plateau, and Conrad Rise) in the off‐axis areas of the Southwest Indian Ridge (SWIR). However, previously obtained magnetic survey lines are sparse and not correctly aligned with the seafloor spreading direction; thus, the detailed spreading history, including the formation of these aseismic ridges, remains an open question. We reconstructed the tectonic history of two segments between the Discovery II and Gallieni fracture zones in the SWIR using newly obtained magnetic data (total and vector magnetic field) and an open‐source magnetic data set. We revealed that the southern Madagascar Ridge and the Del Cano Rise once formed a single bathymetric high and separated by at least Chron 30y, which is quite different from the global age model. In addition, the rises may have formed before Chron 34y, assuming an extinct ridge south of the Del Cano Rise. The two rises have been recognized as having formed by Marion hotspot plume‐induced excess volcanism around the active spreading ridge of the SWIR, which can explain locally isostatically compensated thicker‐than‐normal crust. However, linear magnetic anomalies have not been observed across the main part of these rises, suggesting that magmatic activity controlled by seafloor spreading is unlikely. Like other aseismic ridges in the southern Indian Ocean, these two rises may possibly have been formed partly by continental fragments rather than plume‐induced excess volcanism.
On the Origin of Seismic Anisotropy in the Shallow Crust of the Northern Volcanic Zone, Iceland
Authors: Bacon C. A. , Johnson J. H. , White R. S. , Rawlinson N.
Published: December 2021

The Icelandic crust is a product of its unique tectonic setting, where the interaction of an ascending mantle plume and the Mid‐Atlantic Ridge has caused elevated mantle melting, with the melt accreted and cooled in the crust to form an oceanic plateau. We investigate the strength and orientation of seismic anisotropy in the upper crust of the Northern Volcanic Zone using local earthquake shear‐wave splitting, with a view to understanding how the contemporary stress field may influence sub‐wavelength structure and processes. This is achieved using a data set comprising 50,000 earthquakes located in the top 10 km of the crust, recorded by up to 70 stations over a 9 year period. We find that anisotropy is largely confined to the top 3–4 km of the crust, with an average delay time of 0.10 ± 0.05 s, and an average orientation of the fast axis of anisotropy of N014°E ± 27°, which is perpendicular to the spreading direction of the Eurasian and North American plates (N106°E). These results are consistent with the presence of rift‐parallel cracks that gradually close with depth, the preferential opening of which is controlled by the regional stress field. Lateral variations in the strength of shear wave anisotropy (SWA) reveal that regions with the highest concentrations of earthquakes have the highest SWA values (∼10%), which reflects the presence of significant brittle deformation. Disruption of the orientation of the fast axis of anisotropy around Askja volcano can be related to local stress changes caused by underlying magmatic processes.
A Reference Section Through Fast‐Spread Lower Oceanic Crust, Wadi Gideah, Samail Ophiolite (Sultanate of Oman): Petrography and Petrology
Authors: Koepke J. , Garbe‐Schönberg D. , Müller T. , Mock D. , Müller S. , Nasir S.
Published: December 2021

In the absence of a complete profile through fast‐spreading modern oceanic crust, we established a reference profile through the whole paleo crust of the Samail ophiolite (Sultanate of Oman), which is regarded as the best analogue for fast‐spreading oceanic crust on land. To establish a coherent data set, we sampled the Wadi Gideah in the Wadi‐Tayin massif from the mantle section up to the sheeted dikes and performed different analytical and structural investigations on the same suite of samples. This paper reports our studies of the lower crust, a 5 km thick pile of gabbros, focusing on petrographic features and on the results of mineral analyses. Depth profiles of mineral compositions combined with petrological modeling reveal insights into the mode of magmatic formation of fast‐spreading lower oceanic crust, implying a hybrid accretion mechanism. The lower two thirds of the crust, mainly consisting of layered gabbros, formed via the injection of melt sills and in situ crystallization. Here, upward moving fractionated melts mixed with more primitive melts through melt replenishments, resulting in a slight but distinct upward differentiation trend. The upper third of the gabbroic crust is significantly more differentiated, in accord with a model of downward differentiation of a primitive parental melt originated from the axial melt lens located at the top of the gabbroic crust. Our hybrid model for crustal accretion requires a system to cool the deep crust, which was established by hydrothermal fault zones, initially formed on‐axis at very high temperatures.
A High‐Resolution Whole‐Atmosphere Model With Resolved Gravity Waves and Specified Large‐Scale Dynamics in the Troposphere and Stratosphere
Authors: Becker Erich , Vadas Sharon L. , Bossert Katrina , Harvey V. Lynn , Zülicke Christoph , Hoffmann Lars
Published: December 2021

We present a new version of the HIgh Altitude Mechanistic general Circulation Model (HIAMCM) with specified dynamics. We utilize a spectral method that nudges only the large‐scale flow to MERRA‐2 reanalysis. The nudged HIAMCM simulates gravity waves (GWs) down to horizontal wavelengths of about 200 km from the troposphere to the thermosphere like the free‐running model, including the generation of secondary and tertiary GWs. Case studies show that the simulated large‐scale GWs are consistent with those in the reanalysis, while the medium‐scale GWs compare well with observations in the northern winter 2016 stratosphere from the Atmospheric InfraRed Sounder (AIRS). GWs having wavelengths larger than about 1,350 km can be described with the nonlinear balance equation. The GWs relevant in the stratosphere, however, have smaller scales and require a different approach. We propose that the GW amplification due to kinetic energy transfer from the large‐scale flow combined with GW potential energy flux convergence helps to identify the mesoscale GW sources due to spontaneous emission. The GW amplification is strongest in the region of maximum large‐scale vertical wind shear in the mid‐stratosphere. Maps of the time‐averaged stratospheric GW activity simulated by the HIAMCM and computed from AIRS satellite data show a persistent hot spot over Europe during January 2016. At about 40 km, the average GW amplitudes are maximum in the region of fastest large‐scale flow. We argue that refraction of GWs originating in the troposphere, as well as GWs from spontaneous emission in the stratosphere contribute to this effect.
Increases in Future AR Count and Size: Overview of the ARTMIP Tier 2 CMIP5/6 Experiment
Authors: O’Brien T. A. , Wehner M. F. , Payne A. E. , Shields C. A. , Rutz J. J. , Leung L.‐R. , Ralph F. M. , Collow A. , Gorodetskaya I. , Guan B. , Lora J. M. , McClenny E. , Nardi K. M. , Ramos A. M. , Tomé R. , Sarangi C. , Shearer E. J. , Ullrich P. A. , Zarzycki C. , Loring B. , Huang H. , Inda‐Díaz H. A. , Rhoades A. M. , Zhou Y.
Published: December 2021

The Atmospheric River (AR) Tracking Method Intercomparison Project (ARTMIP) is a community effort to systematically assess how the uncertainties from AR detectors (ARDTs) impact our scientific understanding of ARs. This study describes the ARTMIP Tier 2 experimental design and initial results using the Coupled Model Intercomparison Project (CMIP) Phases 5 and 6 multi‐model ensembles. We show that AR statistics from a given ARDT in CMIP5/6 historical simulations compare remarkably well with the MERRA‐2 reanalysis. In CMIP5/6 future simulations, most ARDTs project a global increase in AR frequency, counts, and sizes, especially along the western coastlines of the Pacific and Atlantic oceans. We find that the choice of ARDT is the dominant contributor to the uncertainty in projected AR frequency when compared with model choice. These results imply that new projects investigating future changes in ARs should explicitly consider ARDT uncertainty as a core part of the experimental design.
Spatial and Temporal Variations of Incision Rate of the Middle Yellow River and Its Tributaries
Authors: Zhong Yuezhi , Willett Sean D. , Picotti Vincenzo , Xiong Jianguo , Zhang Huiping
Published: December 2021

We present a model to reconstruct spatiotemporal variation of uplift along the Jinshan Gorge of the Yellow River of Northern China based on quantitative analysis of the river channel profiles. We focus on the tributaries along the gorge that drain from the Loess Plateau on the Ordos crustal block. Base level fall on a tributary is genetically related to its trunk channel incision through the incision rate of the confluence point. We leverage this relationship to reconstruct a scaled incision history at each confluence point from an inversion analysis of tributary networks governed by the stream power law. In this way, we create an artificial geomorphic marker, that we refer to as a “pseudo‐terrace.” These metrics provide information on the incision history of the Yellow River. Our result shows a recent acceleration of river incision along the southern Jinshan Gorge, including spatial variations indicative of tectonic activity. The northern gorge exhibits more uniform and steady incision rates. This pattern can be attributed to on‐going lithospheric mantle upwelling beneath the southern Ordos Block.
Radar Derived Subglacial Properties and Landforms Beneath Rutford Ice Stream, West Antarctica
Authors: Schlegel Rebecca , Murray Tavi , Smith Andrew M. , Brisbourne Alex M. , Booth Adam D. , King Edward C. , Clark Roger A.
Published: December 2021

Basal properties beneath ice streams and glaciers are known to be a control for ice flow dynamics, hence knowledge of them is crucial for predicting sea level due to changes in glacial dynamics. Basal properties, processes and topography also drive the formation of subglacial landforms. Bed properties beneath Rutford Ice Stream (West Antarctica) have previously been described using seismic acoustic impedance measurements at a sparse spatial coverage. Here, we derive bed properties in a 15 × 17 km grid of surface radar data with coverage and sampling much higher than previous seismic studies. Bed reflection amplitudes in surface radar data were calibrated using sediment porosities (ranging from 0.4–0.5) derived from seismic acoustic impedance. We find the bed properties are spatially variable, consisting of low porosity material in some areas and soft sediment in other areas. Comparison of seismic and surface radar data imply the low porosity material to be a consolidated sediment or sedimentary rock. Mega‐scale glacial lineations (MSGLs) are ubiquitous on the bed and consist of soft, high porosity, probably deforming sediment, consistent with previous interpretations of MSGLs. We find some MSGLs have high reflectivity on their crest, interpreted as water bodies overlying high porosity sediment, whereas the trough around and the upstream end of some landforms consist of low porosity material. Integrating these different observations, we place constraints on possible explanations for the occurrence of water on the crest of landforms.
Riparian Cottonwood Trees and Adjacent River Sediments Have Different Microbial Communities and Produce Methane With Contrasting Carbon Isotope Compositions
Authors: Smits Kristian M. , Grant Daniel S. , Johnston Sara Ellen , Bogard Matthew J. , Rood Stewart B. , Selinger L. Brent , Flanagan Lawrence B.
Published: December 2021

Rivers and their adjacent riparian forests are intimately linked by the exchange of water, nutrients, and organic matter. Both riparian cottonwood trees and adjacent river sediments host microbial communities including archeal methanogens, supporting methane production and emission to the atmosphere. Here we combine microbial community and in vitro stable isotope analyses to characterize the drivers of methane cycling in distinct anoxic habitats (river sediments vs. riparian cottonwood stems) associated with the Oldman River, southern Alberta (Canada). We demonstrate that, differences in the chemical characteristics of organic matter support divergent microbial communities that generate methane from distinct metabolic pathways. Organic matter in river sediments had C/N ratios approximately 50‐fold lower than in tree stems and had more diverse dissolved organic components. Contrasting substrate availability between river sediment and tree stems was likely the primary mechanism for the greater microbial diversity in river sediments than in tree stems, the significantly different bacterial communities, and the trend toward differing abundance of methanogen orders. The methane carbon isotope composition (δ13C values) differed for the tree stem (−103.6‰ to −70.6‰) and river sediment (−55.1‰ to −48.4‰) environments, suggesting that methane was primarily produced via CO2‐reduction in tree stems by Methanobacteriales, while river sediments produced more methane through acetate fermentation primarily by Methanosarcinales. This study demonstrates the importance of organic matter quality and microbial community composition in driving metabolic processes contributing to methane production and emission in rivers and adjacent riparian forests.
Elimination of negative feedback in TLR signalling allows rapid and hypersensitive detection of microbial contaminants
Authors: Seumen Clovis H. T. , Tomasiunaite Urte , Legler Daniel F. , Hauck Christof R.
Published: December 2021

The exquisite specificity of Toll-like receptors (TLRs) to sense microbial molecular signatures is used as a powerful tool to pinpoint microbial contaminants. Various cellular systems, from native human blood cells to transfected cell lines exploit TLRs as pyrogen detectors in biological preparations. However, slow cellular responses and limited sensitivity have hampered the replacement of animal-based tests such as the rabbit pyrogen test or lipopolysaccharide detection by Limulus amoebocyte lysate. Here, we report a novel human cell-based approach to boost detection of microbial contaminants by TLR-expressing cells. By genetic and pharmacologic elimination of negative control circuits, TLR-initiated cellular responses to bacterial molecular patterns were accelerated and significantly elevated. Combining depletion of protein phosphatase PP2ACA and pharmacological inhibition of PP1 in the optimized reporter cells further enhanced the sensitivity to allow detection of bacterial lipoprotein at 30 picogram/ml. Such next-generation cellular monitoring is poised to replace animal-based testing for microbial contaminants.
In-situ detoxification of schedule-I chemical warfare agents utilizing Zr(OH)4@W-ACF functional material for the development of next generation NBC protective gears
Authors: Imran Mohammad , Singh Virendra V. , Garg Prabhat , Mazumder Avik , Pandey Lokesh K. , Sharma Pushpendra K. , Acharya Jyotiranjan , Ganesan Kumaran
Published: December 2021

Chemical warfare agents (CWAs) have become a pivotal concern for the global community and spurred a wide spectrum of research for the development of new generation protective materials. Herein, a highly effective self-detoxifying filter consisting of in-situ immobilized Zirconium hydroxide [Zr(OH)4] over woven activated carbon fabric [Zr(OH)4@W-ACF] is presented for the removal of CWAs. It was prepared to harness the synergistic effect of high surface area of W-ACF, leads to high dispersion of CWAs and high phosphilicity and reactivity of [Zr(OH)4]. The synthesized materials were characterized by ATR-FTIR, EDX, SEM, TEM, XPS, TGA, and BET surface area analyzer. The kinetics of  in-situ degradation of CWAs over Zr(OH)4@W-ACF were studied and found to be following the first-order reaction kinetics. The rate constant was found to be 0.244 min−1 and 2.31 × 10−2 min−1 for sarin and soman, respectively over Zr(OH)4@W-ACF. The potential practical applicability of this work was established by fabricating Zr(OH)4@W-ACF as reactive adsorbent layer for protective suit, and found to be meeting the specified criteria in terms of air permeability, tearing strength and nerve agent permeation as per TOP-08-2-501A:2013 and IS-17380:2020. The degradation products of CWAs were analyzed with NMR and GC–MS. The combined properties of dual functional textile with reactive material are expected to open up new exciting avenues in the field of CWAs protective clothing and thus find diverse application in defence and environmental sector.
Provocation of dry eye disease symptoms during COVID-19 lockdown
Authors: Neti Nutnicha , Prabhasawat Pinnita , Chirapapaisan Chareenun , Ngowyutagon Panotsom
Published: December 2021

To assess the impact of COVID-19 lockdown measures on dry-eye symptoms in a community-based population, a cross-sectional study was conducted during the first wave of the COVID-19 outbreak in Thailand. An online survey was distributed via social media between June and July 2020. The questionnaire elicited information on demographics, dry-eye symptoms, use of visual display terminals, and mental health status. There were 535 respondents. Thirty-seven percent reported having been diagnosed with dry-eye disease (DED). During the lockdown, the mean dry-eye symptom score (DESS) of overall participants dropped significantly from 81.6 ± 15.9 to 79.8 ± 17.4 (P < 0.001). The mean, daily, visual display terminal (VDT) usage increased from 10.55 ± 5.16 to 13.08 ± 5.65 h (P < 0.001). A negative correlation between age and VDT usage was observed in both the normal and lockdown situations. One-quarter of all participants had an abnormal mental health status. The female gender (OR 1.86; 95% CI 1.14–3.04) and increased VDT usage during the lockdown (OR 5.68; 95% CI 3.49–9.23) were independently associated with worsening dry-eye symptoms. The lockdown measures abruptly altered the behaviors and lifestyles of the overall population. Excessive exposure to VDTs were associated with deteriorated dry-eye symptoms, and it possibly contributed to the increased DED incidence in the surveyed population.