bluuebunny/crossref_metadata_2025_split huggingface dataset:
Periphyton as an indicator of saltwater intrusion into freshwater wetlands: insights from experimental manipulations
Authors: Mazzei Viviana , Wilson Benjamin J. , Servais Shelby , Charles Sean P. , Kominoski John S. , Gaiser Evelyn E. 
Published: December 2019

AbstractSaltwater intrusion has particularly large impacts on karstic wetlands of the Caribbean Basin due to their porous, carbonate bedrock and low elevation. Increases in salinity and phosphorus (P) accompanying saltwater intrusion into these freshwater, P‐limited wetlands are expected to alter biogeochemical cycles along with the structure and function of plant and algal communities. Calcareous periphyton is a characteristic feature of karstic wetlands and plays a central role in trophic dynamics, carbon storage, and nutrient cycling. Periphyton is extremely sensitive to water quality and quantity, but the effects of saltwater intrusion on these microbial mats remain to be understood. We conducted an ex situ mesocosm experiment to test the independent and combined effects of elevated salinity and P on the productivity, nutrient content, and diatom composition of calcareous periphyton from the Florida Everglades. We measured periphyton total carbon, nitrogen, and P concentrations and used settlement plates to measure periphyton accumulation rates and diatom species composition. The light and dark bottle method was used to measure periphyton productivity and respiration. We found that exposure to ~1 g P·m−2·yr−1 significantly increased periphyton mat total P concentrations, but had no effect on any other response variable. Mats exposed to elevated salinity (~22 kg salt·m−2·yr−1) had significantly lower total carbon and tended to have lower biomass and reduced productivity and respiration rates; however, mats exposed to salinity and P simultaneously had greater gross and net productivity. We found strong diatom species dissimilarity between fresh‐ and saltwater‐treated periphyton, while P additions only elicited compositional changes in periphyton also treated with saltwater. This study contributes to our understanding of how the ecologically important calcareous periphyton mats unique to karstic, freshwater wetlands respond to increased salinity and P caused saltwater intrusion and provides a guide to diatom indicator taxa for these two important environmental drivers.
Signaling from below: rodents select for deeper fruiting truffles with stronger volatile emissions
Authors: Stephens Ryan B. , Trowbridge Amy M. , Ouimette Andrew P. , Knighton W. Berk , Hobbie Erik A. , Stoy Paul C. , Rowe Rebecca J. 
Published: December 2019

AbstractMany plant and fungal species use volatile organic compounds (VOCs) as chemical signals to convey information about the location or quality of their fruits or fruiting bodies to animal dispersers. Identifying the environmental factors and biotic interactions that shape fruit selection by animals is key to understanding the evolutionary processes that underpin chemical signaling. Using fourElaphomycestruffle species, we explored the role of fruiting depth, VOC emissions, and protein content in selection by five rodent species. We used stable isotope analysis of nitrogen (δ15N) in truffles to estimate fruiting depth, proton‐transfer‐reaction mass spectrometry to determine volatile emission composition, and nitrogen concentrations to calculate digestible protein of truffles. We coupled field surveys of truffle availability with truffle spore loads in rodent scat to determine selection by rodents. Despite presumably easier access to the shallow fruiting species,E. americanus(0.5‐cm depth) andE. verruculosus(2.5‐cm depth), most rodents selected for truffles fruiting deeper in the soil,E. macrosporus(4.1‐cm depth) andE. bartlettii(5.0‐cm depth). The deeper fruiting species had distinct VOC profiles and produced significantly higher quantities of odiferous compounds.Myodes gapperi(southern red‐backed vole), a fungal specialist, also selected for truffles with high levels of digestible protein,E. verruculosusandE. macrosporus. Our results highlight the importance of chemical signals in truffle selection by rodents and suggest that VOCs are under strong selective pressures relative to protein rewards. Strong chemical signals likely allow detection of truffles deep within the soil and reduce foraging effort by rodents. For rodents that depend on fungi as a major food source, protein content may also be important in selecting truffles.
Methodology for tDCS integration with fMRI
Authors: Esmaeilpour Zeinab , Shereen A. Duke , Ghobadi‐Azbari Peyman , Datta Abhishek , Woods Adam J. , Ironside Maria , O'Shea Jacinta , Kirk Ulrich , Bikson Marom , Ekhtiari Hamed 
Published: December 2019

AbstractUnderstanding and reducing variability of response to transcranial direct current stimulation (tDCS) requires measuring what factors predetermine sensitivity to tDCS and tracking individual response to tDCS. Human trials, animal models, and computational models suggest structural traits and functional states of neural systems are the major sources of this variance. There are 118 published tDCS studies (up to October 1, 2018) that used fMRI as a proxy measure of neural activation to answer mechanistic, predictive, and localization questions about how brain activity is modulated by tDCS. FMRI can potentially contribute as: a measure of cognitive state‐level variance in baseline brain activation before tDCS; inform the design of stimulation montages that aim to target functional networks during specific tasks; and act as an outcome measure of functional response to tDCS. In this systematic review, we explore methodological parameter space of tDCS integration with fMRI spanning: (a) fMRI timing relative to tDCS (pre, post, concurrent); (b) study design (parallel, crossover); (c) control condition (sham, active control); (d) number of tDCS sessions; (e) number of follow up scans; (f) stimulation dose and combination with task; (g) functional imaging sequence (BOLD, ASL, resting); and (h) additional behavioral (cognitive, clinical) or quantitative (neurophysiological, biomarker) measurements. Existing tDCS‐fMRI literature shows little replication across these permutations; few studies used comparable study designs. Here, we use a representative sample study with both task and resting state fMRI before and after tDCS in a crossover design to discuss methodological confounds. We further outline how computational models of current flow should be combined with imaging data to understand sources of variability. Through the representative sample study, we demonstrate how modeling and imaging methodology can be integrated for individualized analysis. Finally, we discuss the importance of conducting tDCS‐fMRI with stimulation equipment certified as safe to use inside the MR scanner, and of correcting for image artifacts caused by tDCS. tDCS‐fMRI can address important questions on the functional mechanisms of tDCS action (e.g., target engagement) and has the potential to support enhancement of behavioral interventions, provided studies are designed rationally.
Modulating the global orientation bias of the visual system changes population receptive field elongations
Authors: Merkel Christian , Hopf Jens‐Max , Schoenfeld Mircea Ariel 
Published: December 2019

AbstractThe topographical structure of the visual system in individual subjects can be visualized using fMRI. Recently, a radial bias for the long axis of population receptive fields (pRF) has been shown using fMRI. It has been theorized that the elongation of receptive fields pointing toward the fovea results from horizontal local connections bundling orientation selective units mostly parallel to their polar position within the visual field. In order to investigate whether there is a causal relationship between orientation selectivity and pRF elongation the current study employed a global orientation adapter to modulate the orientation bias for the visual system while measuring spatial pRF characteristics. The hypothesis was that the orientation tuning change of neural populations would alter pRF elongations toward the fovea particularly at axial positions parallel and orthogonal to the affected orientation. The results indeed show a different amount of elongation of pRF units and their orientation at parallel and orthogonal axial positions relative to the adapter orientation. Within the lower left hemifield, pRF radial bias and elongation showed an increase during adaptation to a 135° grating while both parameters decreased during the presentation of a 45° adapter stimulus. The lower right visual field showed the reverse pattern. No modulation of the pRF topographies were observed in the upper visual field probably due to a vertical visual field asymmetry of sensitivity toward the low contrast spatial frequency pattern of the adapter stimulus. These data suggest a direct relationship between orientation selectivity and elongation of population units within the visual cortex.
Analysis of patterns and risk factors regarding the onset of nodules in the contralateral thyroid lobe during follow‐up ultrasonography among patients after unilateral lobectomy for the treatment of papillary thyroid carcinoma
Authors: Sun Chao , Wang Qian , Guo Qianqian , Chang Qing , Liang Xin , Wang Dong , Dai Hongbin , Hu Zhiguang , Xu Tianyu , Feng Wenqi , Li Zhengjiang , Niu Lijuan 
Published: December 2019

AbstractBackgroundThis study tries to find the patterns of new nodules in contralateral thyroid lobe among papillary thyroid carcinomas (PTCs) after lobectomy using ultrasonography.MethodsOf note, 456 PTCs were enrolled. Clinicopathological features of primary tumors and sonographic patterns of new nodules in contralateral lobe were documented. Logistic regression analysis was performed to identify risk factors for new nodules.ResultsThe overall incidence of new nodules was 41.9%. 96.3% of new nodules were no greater than 1 cm while only 10.5% of those were with high suspicion of malignancy. There was no difference in the incidence and sonographic patterns of new nodules between patients with an original tumor size <1 cm (n = 267) vs 1 to 4 cm (n = 189). Multivariate logistic regression analysis showed age (OR, 1.021; 95% CI, 1.001‐1.041; P = .036) played risk factor for new nodules while tumor size >1 cm did not.ConclusionNew nodules in the contralateral lobe were common, but usually small and benign by ultrasound features. Older age was found to be a risk factor to predict new nodules. This study supports lobectomy for 1‐4 cm PTC in terms of incidence of new nodules on the remnant lobe.
Model for End‐Stage Liver Disease With Additional Criteria to Predict Short‐Term Mortality in Severe Flares of Chronic Hepatitis B
Authors: Fung James , Mak Lung‐Yi , Chan Albert Chi‐Yan , Chok Kenneth Siu‐Ho , Wong Tiffany Cho‐Lam , Cheung Tan‐To , Dai Wing‐Chiu , Sin Sui‐Ling , She Wong‐Hoi , Ma Ka‐Wing , Seto Wai‐Kay , Lai Ching‐Lung , Lo Chung‐Mau , Yuen Man‐Fung 
Published: December 2019

Background and Aims
The prognosis in severe acute flares of chronic hepatitis B (AFOCHB) is often unclear. The current study aimed to establish the predictive value using the Model for End‐Stage Liver Disease (MELD) score for short‐term mortality for severe AFOCHB.

Approach and Results
Patients with severe AFOCHB with bilirubin > 50 µmol/L, alanine aminotransferase > 10× upper limit of normal, and international normalized ratio > 1.5 were included. All patients were commenced on entecavir and/or tenofovir. Laboratory results and MELD scores were pooled to calculate mortality at four time points (days 7, 14, 21, and 28). A total of 240 patients were included. Median hepatitis B virus DNA was 7.77 log IU/mL (range, 4.11‐10.06), and 49 (20.4%) were hepatitis B e antigen–positive. The 7, 14, 21, and 28‐day survival was 96.7%, 88.5%, 79.5%, and 72.8%, respectively. Using pooled results derived from 4,201 blood samples, the area under the receiver operating curve for the MELD score to predict day 7, 14, 21, and 28 mortality was 0.909, 0.892, 0.883, and 0.871, respectively. For MELD ≤ 28, mortality at day 28 was low (<25%) compared with > 50% mortality for MELD ≥ 32. For MELD = 28‐32, higher day‐28 mortality was observed for four criteria: age ≥52 years, alanine aminotransferase > 217 U/L, platelets < 127, and abnormal baseline imaging (all P < 0.001). In this MELD bracket, the 28‐day mortality was 0%, 12.1%, 23.8%, 59.4%, and 78.8% for the presence of zero, one, two, three, and four criteria, respectively.

Conclusions
MELD score at any time points can accurately predict the short‐term mortality. Patients with MELD ≥ 28 should be worked up for liver transplantation, and those with MELD = 28‐32 with three to four at‐risk criteria, or MELD ≥ 32 should be listed.
The development of liquid biopsy for research and clinical practice in lymphomas: Report of the 15‐ICML workshop on ctDNA
Authors: Rossi Davide , Kurtz David M. , Roschewski Mark , Cavalli Franco , Zucca Emanuele , Wilson Wyndham H. 
Published: December 2019

AbstractThis report summarizes a closed workshop cosponsored by the American Association for Cancer Research, the European School of Oncology, and the 15th‐International Conference on Malignant Lymphoma to discuss critical open questions on liquid biopsy in lymphoid malignancies, develops a roadmap for their analytical and clinical validation, and prioritizes research areas.
Impact of heat advection on the thermal regime of roads built on permafrost
Authors: Chen Lin , Fortier Daniel , McKenzie Jeffrey M. , Sliger Michel 
Published: December 2019

AbstractIn northern regions, transportation infrastructure can experience severe structural damages due to permafrost degradation. Water infiltration and subsurface water flow under an embankment affect the energy balance of roadways and underlying permafrost. However, the quantification of the processes controlling these changes and a detailed investigation of their thermal impacts remain largely unknown due to a lack of available long‐term embankment temperature data in permafrost regions. Here, we report observations of heat advection linked to surface water infiltration and subsurface flow based on a 9‐year (from 2009 to 2017) thermal monitoring at an experimental road test site built on ice‐rich permafrost conditions in southwestern Yukon, Canada. Our results show that snowmelt water infiltration in the spring rapidly increases temperature in the upper portion of the embankment. The earlier disappearance of snow deposited at the embankment slope increases the thawing period and the temperature gradient in the embankment compared with the natural ground. Infiltrated summer rainfall water lowered the near‐surface temperatures and subsequently warmed embankment fill materials down to 3.6‐m depth. Heat advection caused by the flow of subsurface water produced warming rates at depth in the embankment subgrade up to two orders of magnitude faster than by atmospheric warming (heat conduction). Subsurface water flow promoted permafrost thawing under the road embankment and led to an increase in active layer thickness. We conclude that the thermal stability of roadways along the Alaska Highway corridor is not maintainable in situations where water is flowing under the infrastructure unless mitigation techniques are used. Severe structural damages to the highway embankment are expected to occur in the next decade.
Post‐Last Glacial Maximum evolution of a “fjord‐type” lake based on high‐resolution seismic data: the Lago Roca/Acigami (southern Tierra del Fuego, Argentina/Chile)
Authors: Bran Donaldo Mauricio , Lozano Jorge Gabriel , Civile Dario , Lodolo Emanuele , Cerredo María E. , Tassone Alejandro , Baradello Luca , Grossi Maurizio , Vilas Juan 
Published: December 2019

ABSTRACTLago Roca/Acigami is a “fjord‐type” lake located in the southernmost part of South America, in the proximity of the Beagle Channel. A high‐resolution seismic survey was carried out to analyse the seismic stratigraphy of the lake and to shed some light on the post‐Last Glacial Maximum history of the area. Six seismic units were recognised, and their nature and depositional context were interpreted using seismic stratigraphy and acoustic facies analysis. A buried large ridge was identified within the glacial unit (SU1), interpreted as a frontal moraine that indicates a stabilisation phase. After retreat of the glacier from the basin, the trough was flooded by meltwater and a lake developed (SU2). The seismic facies, from bottom to top, depict a transition from ice‐contact (SU2; SU3) to ice‐distal proglacial conditions (SU4). A thick draping unit (SU5) marks a marine transgressive event and the instauration of a fjord environment in the basin. The marine transgression was a rapid event preceded by a fall in the lake level that caused an erosional unconformity. During the fjord phase the sedimentation remained controlled by meltwater discharge. Sea level fall, and subsequent disconnection from the Beagle Channel was accompanied by a progradation of the glaciofluvial deltaic sediments and the occurrence of several mass‐wasting deposits (SU6). © 2019 John Wiley & Sons, Ltd.
Are All Deep Learning Architectures Alike for Point‐of‐Care Ultrasound?: Evidence From a Cardiac Image Classification Model Suggests Otherwise
Authors: Blaivas Michael , Blaivas Laura 
Published: December 2019

ObjectivesLittle is known about optimal deep learning (DL) approaches for point‐of‐care ultrasound (POCUS) applications. We compared 6 popular DL architectures for POCUS cardiac image classification to determine whether an optimal DL architecture exists for future DL algorithm development in POCUS.MethodsWe trained 6 convolutional neural networks (CNNs) with a range of complexities and ages (AlexNet, VGG‐16, VGG‐19, ResNet50, DenseNet201, and Inception‐v4). Each CNN was trained by using images of 5 typical POCUS cardiac views. Images were extracted from 225 publicly available deidentified POCUS cardiac videos. A total of 750,018 individual images were extracted, with 90% used for model training and 10% for cross‐validation. The training time and accuracy achieved were tracked. A real‐world test of the algorithms was performed on a set of 125 completely new cardiac images. Descriptive statistics, Pearson R values, and κ values were calculated for each CNN.ResultsAccuracy ranged from 96% to 85.6% correct for the 6 CNNs. VGG‐16, one of the oldest and simplest CNNs, performed best at 96% correct with 232 minutes to train (R = 0.97; κ = 0.95; P < .00001). The worst‐performing CNN was the newer DenseNet201, with 85.6% accuracy and 429 minutes to train (R = 0.92; κ = 0.82; P < .00001).ConclusionsSix common image classification DL algorithms showed considerable variability in their accuracy and training time when trained and tested on identical data, suggesting that not all will perform optimally for POCUS DL applications. Contrary to well‐established accuracies for CNNs, more modern and deeper algorithms yielded poorer results.
At‐sea intercomparison of three underway pCO2 systems
Authors: Arruda Ricardo , Atamanchuk Dariia , Cronin Margot , Steinhoff Tobias , Wallace Douglas W. R. 
Published: December 2019

AbstractOcean surface partial pressure of carbon dioxide (pCO2) is a key factor controlling air–sea CO2 fluxes. Most surface pCO2 data are collected with relatively large and complex air–water equilibrators coupled to stand‐alone infrared analyzers installed on Ships of OPportunity (SOOP‐CO2). This approach has proven itself through years of successful deployments, but expansion and sustainability of the future measurement network faces challenges in terms of certification, autonomy, and maintenance, which motivates development of new systems. Here, we compare performance of three underway pCO2 measurement systems (General Oceanics, SubCtech, and Pro‐Oceanus), including a recently developed compact flow‐through, sensor‐based system. The systems were intercompared over a period of 34 days during two crossings of the subpolar North Atlantic Ocean. With a mean difference from the General Oceanics system of −5.7 ± 4.0 μatm (Pro‐Oceanus) and −4.7 ± 2.9 μatm (SubCtech) during the 1st crossing, our results indicate potential for good agreement between the systems. The study highlighted the challenge of assuring accuracy over long periods of time, particularly seen in a worse agreement during the 2nd crossing, and revealed a number of sources of systematic errors. These can influence accuracy of the measurements, agreement between systems and include slow response of membrane‐based systems to pCO2 changes, “within‐ship” respiration due to biofouling, and bias in measurement of the temperature of equilibration. These error sources can be controlled or corrected for, however, if unidentified, their magnitude can be significant relative to accuracy criteria assigned to the highest‐quality data in global databases. The advantages of the compact flow‐through system are presented along with a discussion of future solutions for improving data quality.
Posttransplant Complications Predict Alcohol Relapse in Liver Transplant Recipients
Authors: Kitajima Toshihiro , Nagai Shunji , Segal Antu , Magee Michelle , Blackburn Shaundra , Ellithorpe Donna , Yeddula Siri , Qadeer Yusuf , Yoshida Atsushi , Moonka Dilip , Brown Kimberly , Abouljoud Marwan S. 
Published: December 2019

Alcohol relapse after liver transplantation (LT) in patients with alcohol‐related liver disease (ALD) is a major challenge. Although its association with pretransplant psychosocial factors was extensively studied, the impacts of posttransplant courses on alcohol relapse have not been well investigated. The aim of this study is to analyze peritransplant factors associated with posttransplant alcohol relapse in patients with ALD. This study evaluated 190 adult LT patients with ALD from 2013 to 2019. Risk factors for alcohol relapse were analyzed, focusing on posttransplant chronic complications, which were classified as Clavien‐Dindo classification 3a or higher that lasted over 30 days. The posttransplant alcohol relapse rate was 13.7% (26/190) with a median onset time of 18.6 months after transplant. Multivariate Cox regression analysis revealed that posttransplant chronic complications were an independent risk factor for posttransplant alcohol relapse (hazard ratio [HR], 5.40; P = 0.001), along with psychiatric comorbidity (HR, 3.93; P = 0.001), history of alcohol relapse before LT (HR, 3.00; P = 0.008), and an abstinence period <1.5 years (HR, 12.05; P = 0.001). A risk prediction model was created using 3 pretransplant risk factors (psychiatric comorbidity, alcohol relapse before LT, and abstinence period <1.5 years). This model clearly stratified the risk of alcohol relapse into high‐, moderate‐, and low‐risk groups (P < 0.001). Of the 26 patients who relapsed, 11 (42.3%) continued drinking, of whom 3 died of severe alcoholic hepatitis, and 13 (50.0%) achieved sobriety (outcomes for 2 patients were unknown). In conclusion, posttransplant chronic complications increased the risk of alcohol relapse. Recognition of posttransplant chronic complications in conjunction with the risk stratification model by pretransplant psychosocial factors would help with the prediction of posttransplant alcohol relapse.