bluuebunny/crossref_metadata_2025 huggingface dataset:
Biological Calcification Rate and Species‐Specific Contributions of Coccolithophores to Total Calcite Inventory in the Eastern Indian Ocean
Authors: Liu Haijiao , Yun Misun , Zhang Xiaodong , Zhang Guicheng , Thangaraj Satheeswaran , Huang Ke , Sun Jun
Published: March 2020

Coccolithophores are calcifying protists that have a significant role in marine biological pump through calcite production (CP). We determined the biological calcification rate and ecologically key species (e.g., Gephyrocapsa oceanica) contribution to total calcite stocks in the eastern Indian Ocean (EIO) during spring intermonsoon; this region was quite undersampled compared to other oceanic regions. Our results indicated that the numerically dominant species are of great importance to cell calcite even with low cellular calcite. CP rate in EIO ranged from 0.148 to 85.017 μmol C·m−3·day−1 in the entire data set, which was lower than those in the global ocean. Coccolithophores contributed 8.5% of total phytoplankton carbon fixation. CP acted as a function of light irradiance in the euphotic zone, while a decoupling between CP and primary productivity was found in most of the bottom of euphotic zone. To some degree, this decoupling indicated calcification was more nitrate dependent and less light dependent than photosynthesis. CP/primary productivity ratios were highly variable in our database and were possibly influenced by photoacclimation across various coccolithophore species. As roughly estimated, the turnover rate of coccolith calcite took values around 0.02–0.05 day−1. The association between particulate organic carbon and calcite stocks implied a potential increasing ballast as depth increase. The current profiles of calcification and associated biogeochemical elements obtained from this field study helps our understanding about characteristics of biological pump in the EIO and are valuable for estimating calcification rate in the region using satellite data and numerical modeling.
Goldstein Receives 2019 Yoram J. Kaufman Outstanding Research and Unselfish Cooperation Award
Authors:   AGU
Published: March 2020

Allen H. Goldstein received the Yoram J. Kaufman Outstanding Research and Unselfish Cooperation Award at AGU’s Fall Meeting 2019, held 9–13 December in San Francisco, Calif. The award recognizes “broad influence in atmospheric science through exceptional creativity, inspiration of younger scientists, mentoring, international collaborations, and unselfish cooperation in research.”
Novick Receives 2019 Thomas Hilker Early Career Award for Excellence in Biogeosciences
Authors:   AGU
Published: March 2020

Kimberly Novick received the 2019 Thomas Hilker Early Career Award for Excellence in Biogeosciences at AGU’s Fall Meeting 2019, held 9–13 December in San Francisco, Calif. The award recognizes “a scientist whose research propels any discipline related to the field of biogeosciences.”
Deepwater Horizon and the Rise of the Omics
Authors: Kostka Joel , Joye Samantha , Colwell Rita
Published: March 2020

Microbial genomics techniques came of age following the Deepwater Horizon spill, offering researchers unparalleled insights into how ecosystems respond to such environmental disasters.
Past Seasons Hidden Underground
Authors: Fogerty Christian
Published: March 2020

Belgian paleoclimatologists study a fast-growing stalagmite to glean insight into seasonal climate from centuries past.
Earth’s Skies Transmitted Signs of Life During Lunar Eclipse
Authors: Cartier Kimberly
Published: March 2020

Using upcoming ground- and space-based telescopes, scientists hope to make similar observations of the skies of distant, Earth-like exoplanets.
It’s Time to Revise Estimates of River Flood Hazards
Authors: Sofia Giulia , Nikolopoulos E. , Slater L.
Published: March 2020

Accurately assessing flood hazards requires a better understanding of the feedbacks between natural and human influences on the characteristics of rivers.
River Deltas at the Top of the World
Authors: Thompson Elizabeth
Published: March 2020

The water that filters through river deltas has a large effect on the Arctic Ocean. A new study explores factors that shape Arctic river deltas and how delta form in turn changes water flow.
Six Years with JGR: Space Physics
Authors: Liemohn Mike
Published: March 2020

The outgoing Editor in Chief of JGR: Space Physics reflects on his tenure and expresses his appreciation to all those who contributed to the success of the journal over recent years.
Basalts Turn Carbon into Stone for Permanent Storage
Authors: Cartier Kimberly
Published: March 2020

Scientists have shown that mineral carbonation can permanently capture and store carbon quickly enough and safely enough to rise to the challenge of climate change.
Deepwater Horizon’s Legacy of Science
Authors: Goss Heather
Published: March 2020

The biggest oil spill in history resulted in billions of dollars in settlements—and a massive scientific movement.
Predicting Fast Moving Flash Droughts
Authors: Morton Mary
Published: March 2020

A cross-disciplinary consortium of scientists works to monitor droughts that develop in as little as 2 weeks—whose frequencies are predicted to increase with climate change.
Review of Go-To Iron Analysis Method Reveals Its Pros and Cons
Authors: Shultz David
Published: March 2020

Researchers validated some steps in the standard sequential chemical technique used to extract different forms of iron from rock samples but found inconsistencies in other steps.
Thirty Years, $500 Million, and a Scientific Mission in the Gulf
Authors: Goss Heather
Published: March 2020

Gulf Research Program executive director Lauren Alexander Augustine discusses the impact science can have on communities when given money and time.
The Double‐ITCZ Bias in CMIP3, CMIP5, and CMIP6 Models Based on Annual Mean Precipitation
Authors: Tian Baijun , Dong Xinyu
Published: March 2020

The double‐intertropical convergence zone (ITCZ) bias is one of the most outstanding errors in all previous generations of climate models. Here, the annual double‐ITCZ bias and the associated precipitation bias in the latest climate models for Coupled Model Intercomparison Project (CMIP) Phase 6 (CMIP6) are examined in comparison to their previous generations (CMIP Phase 3 [CMIP3] and CMIP Phase 5 [CMIP5]). All three generations of CMIP models share similar systematic annual multi‐model ensemble mean precipitation errors in the tropics. The notorious double‐ITCZ bias and its big inter‐model spread persist in CMIP3, CMIP5, and CMIP6 models. Based on several tropical precipitation bias indices, the double‐ITCZ bias is slightly reduced from CMIP3 or CMIP5 to CMIP6. In addition, the annual equatorial Pacific cold tongue persists in all three generations of CMIP models, but its inter‐model spread is reduced from CMIP3 to CMIP5 and from CMIP5 to CMIP6.
Large‐Scale Crustal Structure Beneath Singapore Using Receiver Functions From a Dense Urban Nodal Array
Authors: Lythgoe Karen H. , Ong Su Qing Miranda , Wei Shengji
Published: March 2020

Geophysics has a role to play in the development of “smart cities”. This is particularly true for Singapore, one of the world's most densely populated countries. Imaging of Singapore's subsurface is required to identify geological faults, model shaking from future earthquakes, and provide a framework for underground development. A noninvasive geophysical technique that is well suited for urban areas is passive seismic surveys using compact seismic instruments called nodes. Here we image Singapore's crustal structure using receiver functions generated by a 40‐day deployment of a 88 station nodal array. We generate high resolution receiver functions, despite the noisy environment and short recording time and also create common‐conversion point images. Our results reveal a complex crustal structure, containing multiple discontinuities. Azimuthal variations indicate a distinct change in crustal structure on either side of the postulated Bukit Timah fault, which has implications for seismic hazard.
Determining Bathymetry of Shallow and Ephemeral Desert Lakes Using Satellite Imagery and Altimetry
Authors: Armon M. , Dente E. , Shmilovitz Y. , Mushkin A. , Cohen T. J. , Morin E. , Enzel Y.
Published: March 2020

Water volume estimates of shallow desert lakes are the basis for water balance calculations, important both for water resource management and paleohydrology/climatology. Water volumes are typically inferred from bathymetry mapping; however, being shallow, ephemeral, and remote, bathymetric surveys are scarce in such lakes. We propose a new, remote‐sensing‐based, method to derive the bathymetry of such lakes using the relation between water occurrence, during >30 year of optical satellite data, and accurate elevation measurements from the new Ice, Cloud, and Land Elevation Satellite‐2 (ICESat‐2). We demonstrate our method at three locations where we map bathymetries with ~0.3 m error. This method complements other remotely sensed, bathymetry‐mapping methods as it can be applied to: (a) complex lake systems with subbasins, (b) remote lakes with no in‐situ records, and (c) flooded lakes. The proposed method can be easily implemented in other shallow lakes as it builds on publically accessible global data sets.
Structural Variability Within the Kane Oceanic Core Complex From Full Waveform Inversion and Reverse Time Migration of Streamer Data
Authors: Xu Min , Zhao Xu , Canales J. Pablo
Published: March 2020

The origin and distribution of the gabbroic bodies provide crucial information to understand the formation and evolution processes of the oceanic core complexes (OCCs). Nevertheless, images of the shape of the gabbroic bodies across the domes and gabbroic intrusion into the mantle have remained elusive. High‐resolution acoustic early‐arrival full waveform inversion tomography models obtained along and across the Kane OCC characterize the detailed lateral variability in structure and composition of the upper ~2 km of this well‐developed OCC. Reverse time migration images show the gabbroic plutons embedded in mantle rocks are seismically transparent, while more reflective sections correspond to the layered magmatic crust. Lithological interpretation shows heterogeneous distribution of gabbroic bodies within the Kane OCC, indicating strong spatial and temporal variability in magmatism during fault exhumation. Our results will also be of high value for future scientific ocean drilling efforts in the area.
CSN6–TRIM21 axis instigates cancer stemness during tumorigenesis
Authors: Qin Baifu , Zou Shaomin , Li Kai , Wang Huashe , Wei Wenxia , Zhang Boyu , Xiao Lishi , Choi Hyun Ho , Tang Qin , Huang Dandan , Liu Qingxin , Pan Qihao , Meng Manqi , Fang Lekun , Lee Mong-Hong
Published: March 2020

Background

Cancer stem cells (CSCs) are responsible for tumour initiation, metastasis and recurrence. However, the mechanism of CSC formation, maintenance and expansion in colorectal cancer (CRC) remains poorly characterised.

Methods

The role of COP9 signalosome subunit 6 (CSN6) in regulating cancer stemness was evaluated by organoid formation and limited dilution analysis. The role of CSN6–TRIM21–OCT1–ALDH1A1 axis in CSC formation was evaluated in vitro and in vivo. The association of CSN6, TRIM21 and ALDH1A1 expression was validated by a tissue microarray with 267 CRC patients.

Results

The results showed that CSN6 is critical for sphere formation and maintaining the growth of patient-derived organoids (PDOs). We characterised the role of CSN6 in regulating cancer stemness, which involves the TRIM21 E3 ubiquitin ligase, transcription factor POU class 2 homeobox 1 (OCT1) and cancer stem cell marker aldehyde dehydrogenase 1 A1 (ALDH1A1). Our data showed that CSN6 facilitates ubiquitin-mediated degradation of TRIM21, which in turn decreases TRIM21-mediated OCT1 ubiquitination and subsequently stabilises OCT1. Consequently, OCT1 stabilisation leads to ALDH1A1expression and promotes cancer stemness. We further showed that the protein expression levels of CSN6, TRIM21 and ALDH1A1 can serve as prognostic markers for human CRC.

Conclusions

In conclusion, we validate a pathway for cancer stemness regulation involving ALDH1A1 levels through the CSN6–TRIM21 axis, which may be utilised as CRC molecular markers and be targeted for therapeutic intervention in cancers.
Smoking, alcohol consumption and colorectal cancer risk by molecular pathological subtypes and pathways
Authors: Amitay Efrat L. , Carr Prudence R. , Jansen Lina , Roth Wilfried , Alwers Elizabeth , Herpel Esther , Kloor Matthias , Bläker Hendrik , Chang-Claude Jenny , Brenner Hermann , Hoffmeister Michael
Published: March 2020

Background

Smoking and alcohol increase risk for colorectal malignancies. However, colorectal cancer (CRC) is a heterogenic disease and associations with the molecular pathological pathways are unclear.

Methods

This population-based case–control study includes 2444 cases with first-diagnosis CRC and 2475 controls. Tumour tissue was analysed for MSI (microsatellite instability), CIMP (CpG island methylator phenotype), BRAF (B-Raf proto-oncogene serine/threonine kinase gene) and KRAS (Kirsten rat sarcoma viral oncogene homologue gene) mutations. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were estimated for associations between alcohol and smoking and CRC molecular subtypes and pathways.

Results

Current smoking showed higher ORs for MSI-high (OR = 2.79, 95% CI: 1.86–4.18) compared to MSS (OR = 1.41, 1.14–1.75, p-heterogeneity (p-het) = 0.001), BRAF-mutated (mut) (OR = 2.40, 1.41–4.07) compared to BRAF-wild type (wt) (OR = 1.52, 1.24–1.88, p-het = 0.074), KRAS-wt (OR = 1.70, 1.36–2.13) compared to KRAS-mut (OR = 1.26, 0.95–1.68, p-het = 0.039) and CIMP-high (OR = 2.01, 1.40–2.88) compared to CIMP-low/negative CRC (OR = 1.50, 1.22–1.85, p-het=0.101). Current smoking seemed more strongly associated with sessile serrated pathway (CIMP-high + BRAF-mut; OR = 2.39, 1.27–4.52) than with traditional pathway CRC (MSS + CIMP-low/negative + BRAF-wt; OR = 1.50, 1.16–1.94) and no association was observed with alternate pathway CRC (MSS + CIMP-low/negative + KRAS-wt; OR = 1.08, 0.77–1.43). No heterogeneity was observed in alcohol consumption association by molecular subtypes.

Conclusions

In this large case–control study, smoking was more strongly associated with MSI-high and KRAS-wt CRC and with cases showing features of the sessile serrated pathway. Association patterns were less clear for alcohol consumption.
Lycium barbarum polysaccharides ameliorate intestinal barrier dysfunction and inflammation through the MLCK-MLC signaling pathway in Caco-2 cells
Authors: Li Wei , Gao Mingbo , Han Ting
Published: March 2020

Impairment of the intestinal barrier often occurs in inflammatory bowel diseases, and pro-inflammatory factors play a vital role in the pathogenesis of intestinal diseases.
Hydrothermal synthesis of NiFe2O4nanoparticles as an efficient electrocatalyst for the electrochemical detection of bisphenol A
Authors: Kesavan Ganesh , Nataraj Nandini , Chen Shen-Ming , Lin Li-Heng
Published: March 2020

In this study, the sensitive and selective detection of bisphenol A (BPA) was achieved using a screen-printed carbon electrode (NFO/SPCE) modified with hydrothermally synthesized NiFe2O4nanoparticles.
Hybrid granular hydrogels: combining composites and microgels for extended ranges of material properties
Authors: Wyss Céline Samira , Karami Peyman , Bourban Pierre-Etienne , Pioletti Dominique P.
Published: March 2020

This work presents a novel strategy that combines microgel and composite approaches in order to enhance some hydrogel's properties such as swelling, elastic modulus and processing ease as well as to decouple their interdependence.
Polymer nanocomposites with high energy density and improved charge–discharge efficiency utilizing hierarchically-structured nanofillers
Authors: Li Yushu , Zhou Yao , Zhu Yujie , Cheng Sang , Yuan Chao , Hu Jun , He Jinliang , Li Qi
Published: March 2020

A hierarchical nanostructure as a new design of nanofillers is demonstrated for high-energy-density dielectric polymer nanocomposites.
Fault phase selection method applied to tie line of renewable energy power stations
Authors: Xu Kehan , Zhang Zhe , Lai Qinghua , Yin Xianggen
Published: March 2020

The short‐circuit current characteristics fed by the renewable energy source are quite different from those of the synchronous generator, which may lead to the phase selection error or failure of the traditional fault phase selection component, and then affect the operating reliability of the distance protection and the automatic reclosing. This study analyses the existing issues in the application of traditional phase selection components to the tie‐line of renewable energy power, according to the fault characteristics of different renewable energy sources such as photovoltaic power source, direct‐drive wind turbine and doubly‐fed wind turbine. Furthermore, the sequence voltage expressions in the case of different types of faults, which takes account of the influence of the renewable energy type and the transition resistance, are theoretically derived. Hereby, a novel phase selection method by using sequence‐voltage phase comparison and phase‐voltage amplitude comparison is proposed. This method is applicable to the tie line of different types of renewable energy power station, and possesses the superiorities of high reliability and strong tolerance towards large fault transition resistance. Digital simulation results verify the favourable performance of the proposed method.
Filtering rat‐race couplers with impedance transforming characteristics based on terminated coupled line structures
Authors: Dong Gaoya , Wang Weimin , Wu Yongle , Liu Yuanan , Tentzeris Manos M.
Published: March 2020

In this study, a series of rat‐race couplers with bandpass filtering responses and impedance transforming characteristics are presented based on novel coupled‐line structures. Firstly, a novel filtering rat‐race coupler core circuit is proposed by introducing coupled‐line structures into conventional rat‐race coupler. Then, a series of rat‐race couplers with enhanced filtering responses and stopband rejections are constructed by employing various types of impedance transformers. The even‐ and odd‐mode methods are adopted to explain the operating mechanisms. Finally, a filtering rat‐race coupler prototype with a fractional bandwidth of 35.2% is designed and measured. The measured results show high passband selectivity, good out‐of‐band rejection and isolation performances, which is attractive for practical application.
Four‐hundred gigahertz broadband multi‐branch waveguide coupler
Authors: Zhang Bo , Niu Zhongqian , Wang Jiale , Ji Dongfeng , Zhou Tianchi , Liu Yang , Feng Yinian , Hu Yi , Zhang Jicong , Fan Yong
Published: March 2020

Terahertz technology is a hotspot in the current academic research. In this study, a 400 GHz broadband multi‐branch waveguide hybrid coupler is designed, but it is very difficult to fabricate. In order to release the processing difficulty, a modified five‐branch hybrid coupler has also been designed, fabricated and measured. The hybrid coupler consists of five modified branches and has been optimised to a great performance, which increases the operation bandwidth. Compared to the traditional five‐branch hybrid coupler design, this structure has a wider operation bandwidth and the bandwidth is almost the same as traditional seven‐branch hybrid coupler. Based on this model, the performance of the coupler is optimised by HFSS software. The measurement results show good performance that >18 dB return loss (S11) and isolation (S23), 90° ± 2° phase difference and 0.3 dB amplitude imbalance are obtained in the frequency range of 380–460 GHz, agreeing well with the simulation results.
Dynamic characteristics of a hydro‐turbine governing system considering draft tube pressure pulsation
Authors: Guo Pengcheng , Zhang Hao , Gou Dongming
Published: March 2020

Hydropower takes on many tasks such as peak regulation and frequency modulation in the power system. In the actual operation process of the hydro‐turbine governing system, there is a certain degree of pressure pulsation in the draft tube. When the system is under unrated operating conditions, the draft tube pressure pulsation is more intense, and its dynamic behaviour becomes more complicated. In this study, the draft tube pressure pulsation is introduced into the dynamic model of the hydro‐turbine governing system, and its influences on the transient characteristics of the system are analysed under unrated conditions and rated conditions. The authors find that compared with the rated conditions, the draft tube pressure pulsation under unrated conditions has more significant effects on the transient characteristics of the system. A damped frequency of pressure pulsation is proposed in this study which provides an efficient method of regulating the dynamic behaviour of the system in real operation. All these findings are expected to be helpful for further study of the influence of pressure pulsation on transient characteristics of hydropower systems and improving their dynamic characteristics under operating conditions.
Highly reliable DC voltage control strategy for modular multilevel converter based‐UPFC
Authors: Lu Dongsheng , Wang Zhenquan , Lou Yue , Guo Xueying , Zong Liu , Wei Xiaojing
Published: March 2020

The DC bus voltage of the unified power flow controller (UPFC) is closely related to the active power balance between the series and the shunt sides. In this study, a highly reliable modular multilevel converter (MMC)‐UPFC DC bus voltage control strategy is proposed to ensure the continuous and stable operation of the MMC‐UPFC. The DC voltage coordinated control strategy of dual converters in the shunt side, which combines the constant DC voltage control, droop control and margin control, is based on the topology configuration of the main converter and the standby converter. The DC voltage coordinated control strategy is adopted for different control targets under conditions of small‐range adjustment of active power flow, wide‐range adjustment, and the shunt‐side converter failure, to achieve reliable and stable operation of UPFC under different operating conditions. Finally, a simulation model was established under the MATLAB/Simulink environment to verify the feasibility of this control strategy.
New ultracool dwarf neighbours within 20 pc fromGaiaDR2
Authors: Scholz R.-D.
Published: March 2020

Aims.TheGaiadata release 2 (DR2) contains > 6000 objects with parallaxes (Plx + 3 × e_Plx) > 50 mas, placing them within 20 pc from the Sun. Because the expected numbers based on extrapolating the well-known 10 pc census are much lower, nearbyGaiastars need a quality assessment. The 20 pc sample of white dwarfs (WDs) has been verified and completed withGaiaDR2. We here confirm and complete the 20 pc sample of ultracool dwarfs (UCDs) with spectral types ≳M7 and givenGaiaDR2 parallaxes.

Methods.Dividing theGaiaDR2 20 pc sample into subsamples of various astrometric and photometric quality, we studied their distribution on the sky, in theMGversusG − RPcolour-magnitude diagram (CMD), and as a function ofGmagnitude and total proper motion. After excluding 139 known WDs and 263 known UCDs from the CMD, we checked all remaining ≈3500 candidates withMG >  14 mag (used to define UCDs in this study) for the correctness of theirGaiaDR2 proper motions by visual inspection of finder charts, comparison with proper motion catalogues, and comparison with our own proper motion measurements. For confirmed UCD candidates we estimated spectral types photometrically usingGaiaand near-infrared absolute magnitudes and colours.

Results.We failed to confirm new WDs, but found 50 new UCD candidates that are not mentioned in three previous studies usingGaiaDR2. They have relatively small proper motions and low tangential velocities and are concentrated towards the Galactic plane. Half of them have spectral types in SIMBAD and/or previous non-Gaiadistance estimates that placed them already within 20 pc. For 20 of the 50 objects, we estimated photometric spectral types of M6−M6.5, slightly below the classical UCD spectral type limit. However, seven L4.5−L6.5, four L0−L1, five M8.5−M9.5, and three M7−M8 dwarfs can be considered as completely new UCDs discoveries within 20 pc based onGaiaDR2. Four M6.5 and two L4.5 dwarfs have high membership probabilities (64%−99%) in the ARGUS, AB Doradus, or Carina Near young moving groups.
An acceptability index based approach for solving shortest path problem on a network with interval weights
Authors: Ebrahimnejad Ali
Published: March 2020

Based on the acceptability index for comparison of any two imprecise values, efficient algorithms have been proposed in the literature for solving shortest path (SP) problem when the weights of connected arcs in a transportation network are represented as interval numbers. In this study, a generalized Dijkstra algorithm is proposed to handle the SP problem with interval weights. Here it is shown that once the acceptability index is chosen, the interval SP problem is converted into crisp one, which is easily solved by the standard SP algorithms. The main contribution here is the reduction of the computational complexity of the existing algorithm for solving interval SP problem. To show the advantages of the proposed algorithm over existing algorithm the numerical example presented in literature is solved using the proposed algorithm and the obtained results are discussed. Moreover, an small sized telecommunication network is provided to illustrate the potential application of the proposed method. Finally, the practical relevance of the proposed algorithm is evaluated by means of a large scale pilot case where a pharmaceutical shipment between the cities in Iran should be transported.
Innere Bilder in der Arzt-Patienten-Beziehung
Authors: Hauler Barbara
Published: March 2020

Innere Bilder tauchen oft spontan im Gespräch zwischen Patient und Arzt auf. Der Beitrag möchte vermitteln, wie diese Bilder das Kommunikationsgeschehen bereichern. Sie können zu Imaginationen weiter entwickelt werden, die das Verständnis der Arzt-Patienten-Beziehung und des Krankheitsgeschehens vertiefen.
Intraoperative Neurophysiologic Monitoring Correlates with Neurologic Outcome After Endovascular and Surgical Treatment of a Cervical Arteriovenous Malformation
Authors: Sánchez Roldán M. Angeles , Tellez Maria J. , Mora Francisco , Ghatan Saadi , Roonprapunt Chanland , Ulkatan Sedat
Published: March 2020

Background The treatment of spinal intramedullary arteriovenous malformations (AVMs) presents the risk of spinal cord ischemia because of the vascular nidus and their feeding arteries involving and supplying the spinal cord parenchyma. The multimodal approach includes endovascular embolization and microsurgical excision, both benefiting from intraoperative neurophysiologic monitoring. We present a case study of a patient who underwent several staged embolizations and open surgery for microsurgical excision.

Patient A 32-year-old man who presented with a recurrent glomus-type intramedullary AVM in the cervical spinal cord, located at the C5–C6 segment, with progressive neurologic deterioration.

Methods Somatosensory evoked potentials (SEPs) and transcranial motor evoked potentials (MEPs) were performed during three embolizations, a provocative test, and surgery, in addition to D-wave during microsurgical excision.

Results Abolished hand MEP and drop in SEP during a provocative test guided the surgeon to embolize from a safer vessel with no acute neurologic deficit after three embolizations. Before surgery, an angiography showed the left posterior spinal artery supplying the AVM. After resecting the vascular nidus from the spinal parenchyma, left-hand MEP decreased in amplitude and later abolished, and SEP decreased. Interestingly, no D-wave or distal MEPs were affected. Weakness in the left hand immediately and 2 weeks postoperatively advocates for metameric spinal cord ischemia with preservation of long spinal cord pathways.

Conclusions Intraoperative neurophysiologic monitoring correlates with neurologic outcome after endovascular and surgical treatment of a cervical AVM. Intraoperative monitoring provides continuous functional information of long and metameric spinal cord pathways, which is critical when deciding on the vessel to be embolized and during microsurgical excision where the surgeon is in less control of the AVM hemodynamic flow.
Case Report of Cerebellar Endometriosis
Authors: Meggyesy Michael , Friese Michael , Gottschalk Joachim , Kehler Uwe
Published: March 2020

Endometriosis is a disorder in women which is characterized by extrauterine manifestations. We describe a case of cerebellar endometriosis in a 39-year-old woman who underwent posterior fossa decompression multiple times without establishing a correct diagnosis. Her neurologic status progressively worsened due to chronic hydrocephalus and brainstem compression by cysts. Late in the clinical course, histology from the cyst wall was taken that revealed endometriosis with clear cells and positive immunohistology for progesterone and estrogen receptors. Treatment with gestagens was started but did not improve the patient's status. In patients with chronic recurring intracranial cysts and hydrocephalus, cerebral endometriosis should be considered.
Comparison of Outcomes of End-to-End versus End-to-Side Anastomoses in Lower Extremity Free Flap Reconstructions
Authors: Broer Peter Niclas , Moellhoff Nicholas , Mayer Julius M. , Heidekrueger Paul I. , Ninkovic Milomir , Ehrl Denis
Published: March 2020

Background Whether to perform an end-to-end (ETE) versus end-to-side (ETS) arterial anastomosis is an integral part of preoperative planning and intraoperative decision making in free flap-based reconstructions. This study evaluated the impact of microsurgical anastomotic technique on outcomes of lower extremity reconstructions, with a focus on patients with peripheral arterial disease (PAD).

Methods Over a 6-year period, 425 patients underwent 437 microvascular lower extremity free flap reconstructions with fasciocutaneous anterolateral thigh- or gracilis muscle flaps at a single surgical center. The cases were divided into an ETE (n = 297 patients) versus ETS (n = 128 patients) group according to the anastomotic technique. A retrospective analysis of patients' demographics, perioperative details, surgical complications, free flap types, recipient sites, flap survival, and the potential impact of PAD on outcomes was performed. Patient groups were comparable regarding comorbidities, American Society of Anesthesiologists scores, types of performed free flaps and recipient sites.

Results We found no significant differences between the ETE versus ETS groups regarding the rate of major or minor complications (p > 0.05). Specifically, in patients suffering from PAD (n = 64) the type of arterial anastomosis had no effect on the outcome.

Conclusion Overall, no significant differences in outcomes were observed when comparing the types of performed arterial anastomosis. This observation also held true for the subgroup of patients with PAD. Given that an ETS anastomosis did not increase the risk to encounter complications while preserving distal perfusion, we believe that this technique is the method of choice, especially in patients with impaired vascular status.
Bilateral Sudden Sensorineural Hearing Loss in Waldenström’s Macroglobulinemia: Case Report and Review of the Literature
Authors: Shoman Nael M. , Aldahmashi Thamir
Published: March 2020

Objective Waldenström’s macroglobulinemia (WM) is a rare indolent B-cell lymphoproliferative disorder, representing 1 to 2% of all hematological malignancies. Involvement of the inner ear is rare with only case reports published over the past six decades.

Methods The occurrence of bilateral sudden sensorineural hearing loss is exceeding rare, with limited published data in the literature. We present a case of a 62-year-old man diagnosed with WM who presented with bilateral sequential sudden sensorineural hearing loss.

Results A few months following his WM diagnosis, he experienced sudden hearing loss in his left ear. He was treated with a course of oral steroids with no improvement. Three months following this incident, he experienced a similar sudden loss of hearing in his right ear. Treatment for WM was initiated. A repeat hearing test, done 1 week later, did not show any significant improvement in his right hearing.

Conclusion The clinical course of WM is highly variable, with relatively infrequent involvement of lymph nodes, spleen, or liver. The inner ear is rarely involved. In this article, otologic clinical presentation is discussed, along with a review of the literature on hearing loss in WM.
Etiology, Pathology, and Classification of Atrial Fibrillation
Authors: Nayak Srishti , Natarajan Balaji , Pai Ramdas G.
Published: March 2020

Atrial fibrillation (AF) is a disorganized tachyarrhythmia with significant public health importance due to high morbidity, mortality, and health-care costs. Incidence rate of AF is on the rise and there are several modifiable and nonmodifiable risk factors that are responsible. Exact mechanisms and pathogenesis of AF are still poorly understood, yet they still have great implications in management. The aim of this article is to summarize the epidemiology, major risk factors, and their role in the pathogenesis of AF. Finally, we have reviewed the classification of AF as per professional society guidelines.
Risk and Consequences of Postoperative Delirium in Cardiac Surgery
Authors: Sugimura Yukiharu , Sipahi Nihat Firat , Mehdiani Arash , Petrov Georgi , Awe Mareike , Minol Jan Philipp , Boeken Udo , Korbmacher Bernhard , Lichtenberg Artur , Dalyanoglu Hannan
Published: March 2020

Background Delirium is a common complication after cardiac surgery that leads to increased costs and worse outcomes. This retrospective study evaluated the potential risk factors and postoperative impact of delirium on cardiac surgery patients.

Methods One thousand two hundred six patients who underwent open-heart surgery within a single year were included. Uni- and multivariate analyses of a variety of pre, intra-, and postoperative parameters were performed according to differences between the delirium (D) and nondelirium (ND) groups.

Results The incidence of delirium was 11.6% (n = 140). The onset of delirium occurred at 3.35 ± 4.05 postoperative days with a duration of 5.97 ± 5.36 days. There were two important risk factors for postoperative delirium: higher age (D vs. ND, 73.1 ± 9.04 years vs. 69.0 ± 11.1 years, p < 0.001) and longer aortic cross-clamp time (D vs. ND, 69.8 ± 49.9 minutes vs. 61.6 ± 53.8 minutes, p < 0.05). We found that delirious patients developed significantly more frequent postoperative complications, such as myocardial infarction (MI) (D vs. ND, 1.43% [n = 3] vs. 0.28% [n = 2], p = 0.05), cerebrovascular accident (D vs. ND, 10.7% [n = 15] vs. 3.75% [n = 40], p < 0.001), respiratory complications (D vs. ND, 16.4% [n = 23] vs. 5.72% [n = 61], p < 0.001), and infections (D vs. ND, 36.4% [n = 51] vs. 16.0% [n = 170], p < 0.001). The hospital stay was longer in cases of postoperative delirium (D vs. ND, 23.2 ± 13.6 days vs. 17.4 ± 12.8 days, p < 0.001), and fewer patients were discharged home (D vs. ND, 56.0% [n = 65] vs. 66.8% [n = 571], p < 0.001).

Conclusions Because the propensity for delirium-related complications is high after cardiac surgery, a practical, preventative strategy should be developed for patients with perioperative risk factors, including higher age and a longer cross-clamp time.
Thrombocytopenia and Absent Radii Syndrome with Tetralogy of Fallot and Hypothyroidism
Authors: Sahu Manoj Kumar , Singh Dharmraj , Saurav Gaind , Singh Sarvesh Pal , Rajashekar Palleti
Published: March 2020

Thrombocytopenia and absent radii (TAR) syndrome is a rare genetic disorder characterized by congenital absence of both radii, presence of both the thumbs, and severe thrombocytopenia which resolves spontaneously in childhood. The incidence is 0.5 to 1 per 100,000 live births and this syndrome may be associated with anomalies of other organs like gastrointestinal (milk protein allergy), genitourinary, cerebral, cardiac, renal, and so forth. Involvement of endocrine system is not reported in the literature. We describe a case of TAR syndrome with tetralogy of Fallot and newly diagnosed hypothyroidism.
Psychological Stress in Myocardial Infarction Patients
Authors: Vaswani Daya
Published: March 2020

Background The interplay between mental and physical health is an area of inadequate research and hence poorly understood. However, decades of research have made surprising revelations—that both may actually cause each other—but the precise nature of these links is not clearly defined. Hence, the aim of this paper is to determine the prevalence of undiagnosed depressive and anxiety symptoms in patients presenting with Acute Myocardial Infarction (MI) in the Intensive Care Unit (ICU) of our hospital.

Materials and Methods This is a cross-sectional study conducted on 100 patients admitted with acute MI in the cardiology ICU of our tertiary hospital. A detailed history was obtained, including socioeconomic history and complete medical history. The Perceived Stress Scale (PSS) was used to assess subjective psychological stress. Patient Health Questionnaire-9 (PHQ9) was used to diagnose unrecognized depression, and Generalized Anxiety Disorder-7 (GAD7) was used to identify anxiety disorder among patients.

Results Out of total study population, 35% (n = 35) were females (mean age: 57.44 ± 13.54 years) and 65% (n = 65) were males (mean age: 55.90 ± 10.81 years). 82% (n = 82) of the patients were found to have subjective psychological distress, among which 70.73% (n = 58) patients had depressive symptoms, with 5.17% (n = 3) having major depression. Of the total patients diagnosed to have depression, 68.96% (n = 40) patients were males and 31.03% (n = 18) were females, with two out of three patients with major depression being females. Among the total study patients, 24% (n = 24) had anxiety symptoms, out of which 58.3% (n = 14) were males and 41.6% (n = 10) were females, with only two patients categorized as having severe anxiety disorder, both being females. Univariate analysis of study variables with depression showed that increased incidence of subjective psychological stress and lesser physical activity were strongly associated with depressive symptoms (P value: 0.04 and 0.01 respectively). Among the total study patients, 24% (n = 24) had anxiety symptoms out of which 58.3% (n = 14) were males and 41.6% (n = 10) were females, with only two patients categorized as having severe anxiety disorder, both being females. Univariate analysis of study variables with anxiety disorder showed significant association of older age > 60 years (P value 0.002), hypertension (HTN) (P value 0.001), T2DM (P value 0.02), and coexisting T2DM and HTN (P value 0.05), with anxiety disorder. Smoking and alcoholism also demonstrated an independent association with anxiety disorder (P value 0.04 and 0.01 respectively). Lesser physical activity demonstrated a strong association with anxiety (P value 0.0001).

Conclusion The prevalence of psychological stress among MI patients is high, with depression existing in 70.7% of patients, notably, major depression was more in females. Of the total study population, 24% of patients had anxiety, where a severe degree of anxiety was more in female patients.
To Evaluate the Influence of Different Implant Thread Designs on Stress Distribution of Osseointegrated Implant: A Three-Dimensional Finite-Element Analysis Study–An In Vitro Study
Authors: Sharma Chhavi , Kalra Tarun , Kumar Manjit , Bansal Ajay , Chawla Anupreet Kaur
Published: March 2020

Introduction Dental implants are common treatment modality for tooth loss which leads to unaesthetic appearance and may also cause deterioration of mastication and speech. The aim of implant therapy in dentistry is to restore tissue contour, function, comfort, aesthetic, and speech. Dental implant role is to transfer the mechanical force created during chewing to the supporting osseous tissues within the mandible and maxilla. The importance of biomechanical factors such as the bone-implant interface, implant thread design, the length and diameter of implants, type of loading, the quality and quantity of surrounding bone have been strained by various authors. The selection of implant thread design plays an important role in the outcome of the treatment. This study was done to evaluate the influence of different thread designs on stress distribution of osseointegrated implant using three-dimensional (3D) finite-element analysis.

Materials and Methods Three implants with different thread designs, namely V-thread, buttress, and reverse buttress thread designs were considered and dimensions were standardized. The site considered was the mandibular molar region with cortical and cancellous bone assuming to be isotropic and homogeneous. The implant modeling was done with the ANSYS 18.1 software. Axial load (100N) and buccolingual load (50N) were applied. The stresses were calculated as Von Mises stress criterion.

Results Minimum von mises Stress concentration was seen for tapered implant body with reverse buttress thread design under axial load 100N and tapered implant body with V-thread under buccolingual load of 50N at cortical bone which signifies bone preservation. Stress levels were observed maximum at implant and minimum at the cancellous bone.

Conclusion Hence, within the limitations of this study the results obtained can be applied clinically for appropriate selection of implant thread design for a predictable success of implant therapy.
Introduction
Authors: Comrie Bernard
Published: March 2020

This Introduction highlights some of the recurrent themes of the volume, in particular two diachronic
paths: (i) resultative > perfect > perfective past; (ii) relaxation of an initial constraint restricting the perfect to
results attributed to the patient. The latter leads to a discussion of be and have perfects, including
English and Dutch data that point to important methodological caveats.
The development of the perfect within IE verbal systems
Authors: Kümmel Martin Joachim
Published: March 2020

This paper gives an overview of the development of perfect forms in the branches of Indo-European. It
begins with a discussion of the perfect in Proto-Indo-European and problems with its reconstruction. Special attention is paid
to the formal and functional discrepancies between the Common Indo-European perfect and related forms in the Anatolian branch.
The paper then traces the continuation of the Proto-Indo-European perfect form and gives an overview of various new
constructions which take the place of the original form. It concludes with a short discussion of the semantic shifts which
take place in the different Indo-European branches.
Celtic past tenses past and present
Authors: Wigger Arndt
Published: March 2020

Past tense marked for perfective aspect, resultative, or other typical features of grammatical perfect
forms is clearly in evidence in all of the modern Celtic languages, although not normally listed in the standard paradigms. An
overview of usages in the modern languages will be given here, the major structures being of fairly recent origin. The formal
structure is periphrastic throughout, divided between an older type employing the preposition ‘after’, and a newer one which
shows some resemblance to the have-perfects in many other European languages. In agreement with previous authors,
these major formal types will be referred to as p1 and p2 respectively. As the question of active vs.
passive is crucial here, this side of the matter will be discussed to some extent, as will be the issue of syntactically
reduced structures containing traces of a perfect tense. Questions of contact-induced change will not be addressed in this
descriptive overview, except on some minor points. Given the grammatical and semantic complexity of this matter, with
different developments over six literary languages and a multitude of dialectal varieties, the early (pre)history will not be
discussed in much detail here.
Paradigmatisation of the perfect and resultative in Tocharian
Authors: Seržant Ilja A.
Published: March 2020

In this chapter I consider a periphrastic construction based on the resultative participle and the
auxiliary. The semantics are those typical of a perfect grammaticalized from a resultative construction. The combination with
time adverbials as well as contextual information show that the reference time coincides with the moment of speech and is not
prior to it. In addition to the inherited meaning of the resultative perfect, other meanings typical of a perfect are also
found, e.g., the experiential perfect. Finally, there are no selectional input restrictions: all Vendler classes are found in
this construction – a situation that may not be found with early resultatives. Even though, these properties suggest an
advanced grammaticalisation degree of the construction, there are also indications for its recent development. For example,
there is no evidence for a non-compositional interpretation of the auxiliary such as remote past – a meaning facet typical of
pluperfects.
The perfect in Middle and New Iranian languages
Authors: Jügel Thomas
Published: March 2020

This paper is the first step towards a description of the category ‘perfect’ in Middle and New Iranian
languages. It attempts a comprehensive overview of the various forms that developed in the course of the past 2000 years,
arriving at a typological classification of the Iranian languages. The comparison of perfects with their paradigmatic
counterparts helps delimit the functional range that the perfect covered or covers, which, owing to lack of information, is as
much as can be achieved for the majority of the Iranian languages. The diachronic perspective provides insight into the
functional development of the perfect, which began with a resultative construction, and which in turn developed via a perfect
into a simple past or past perfective (in some cases more than once). The paper concludes with a brief overview of some
special perfect constructions such as double perfects, evidentials and perfect continuous forms.
The perfect in North-Eastern Neo-Aramaic
Authors: Khan Geoffrey
Published: March 2020

This paper describes the form and function of the perfect in the North-Eastern Neo-Aramaic (NENA) dialects,
a highly diverse subgroup of Neo-Aramaic originally spoken east of the Tigris river. After a short description of the
expression of the perfective in § 1, a detailed classification of the various forms of
the perfect is presented in § 2. Many of these forms have developed under the
influence of the verbal system of Iranian languages of the area (§ 3). The perfect in
NENA has a wide range of functions, some of them not commonly documented elsewhere, such as the use of the perfect to express
the remote past and its use in presuppositional contexts (§ 4). Some of these
functions have parallels in the function of the perfect in Iranian languages in contact with NENA (§ 5). Finally, an analysis is given of the NENA perfect within a Reichenbachian framework (§ 6). The common denominator of the diverse functions of the NENA perfect is the fact
that the event is viewed from an indirect reference point and as a result the event is defocalized. The separation between the
event and the reference point (e < r), which is the hallmark of the perfect, need not be temporal distance, but may be
cognitive distance from the focus of attention due to the presuppositional information status of the event.