bluuebunny/crossref_metadata_2025_split huggingface dataset:
Does conventional specimen radiography after neoadjuvant chemotherapy of breast cancer help to reduce the rate of second surgeries?
Authors: Schaefgen Benedikt , Funk Annika , Sinn H.-P. , Bruckner Thomas , Gomez Christina , Harcos Aba , Stieber Anne , Haller Annabelle , Nees Juliane , Togawa Riku , Pfob André , Hennigs André , Hederer Johanna , Riedel Fabian , Fastner Sarah , Sohn Christof , Heil Jörg , Golatta Michael 
Published: December 2021

Abstract
Purpose
This is the first study to systematically evaluate the diagnostic accuracy of intraoperative specimen radiography on margin level and its potential to reduce second surgeries in patients treated with neoadjuvant chemotherapy.

Methods
This retrospective study included 174 cases receiving breast conserving surgery (BCS) after neoadjuvant chemotherapy (NACT) of primary breast cancer. Conventional specimen radiography (CSR) was performed to assess potential margin infiltration and recommend an intraoperative re-excision of any radiologically positive margin. The histological workup of the specimen served as gold standard for the evaluation of the accuracy of CSR and the potential reduction of second surgeries by CSR-guided re-excisions.

Results
1044 margins were assessed. Of 47 (4.5%) histopathological positive margins, CSR identified 9 correctly (true positive). 38 infiltrated margins were missed (false negative). This resulted in a sensitivity of 19.2%, a specificity of 89.2%, a positive predictive value (PPV) of 7.7%, and a negative predictive value (NPV) of 95.9%. The rate of secondary procedures was reduced from 23 to 16 with a number needed to treat (NNT) of CSR-guided intraoperative re-excisions of 25.
In the subgroup of patients with cCR, the prevalence of positive margins was 10/510 (2.0%), PPV was 1.9%, and the NNT was 85.

Conclusion
Positive margins after NACT are rare and CSR has only a low sensitivity to detect them. Thus, the rate of secondary surgeries cannot be significantly reduced by recommending targeted re-excisions, especially in cases with cCR. In summary, CSR after NACT is inadequate for intraoperative margin assessment but remains useful to document removal of the biopsy site clip.
Rigorous Upper Bound for the Discrete Bak–Sneppen Model
Authors: Volkov Stanislav 
Published: December 2021

AbstractFix some $$p\in [0,1]$$

p
∈
[
0
,
1
]

and a positive integer n. The discrete Bak–Sneppen model is a Markov chain on the space of zero-one sequences of length n with periodic boundary conditions. At each moment of time a minimum element (typically, zero) is chosen with equal probability, and it is then replaced alongside both its neighbours by independent Bernoulli(p) random variables. Let $$\nu ^{(n)}(p)$$

ν

(
n
)

(
p
)

be the probability that an element of this sequence equals one under the stationary distribution of this Markov chain. It was shown in Barbay and Kenyon (in Proceedings of the Twelfth Annual ACM-SIAM Symposium on Discrete Algorithms (Washington, DC, 2001), pp. 928–933, SIAM, Philadelphia, PA, 2001) that $$\nu ^{(n)}(p)\rightarrow 1$$

ν

(
n
)

(
p
)

→
1

as $$n\rightarrow \infty $$

n
→
∞

when $$p>0.54\dots $$

p
>
0.54
⋯

; the proof there is, alas, not rigorous. The complimentary fact that $$\displaystyle \limsup _{n\rightarrow \infty } \nu ^{(n)}(p)< 1$$

lim sup

n
→
∞

ν

(
n
)

(
p
)

<
1

for $$p\in (0,p')$$

p
∈
(
0
,

p
′

)

for some $$p'>0$$

p
′

>
0

is much harder; this was eventually shown in Meester and Znamenski (J Stat Phys 109:987–1004, 2002). The purpose of this note is to provide a rigorous proof of the result from Barbay and Kenyon (in Proceedings of the Twelfth Annual ACM-SIAM Symposium on Discrete Algorithms (Washington, DC, 2001), pp. 928–933, SIAM, Philadelphia, PA, 2001), as well as to improve it, by showing that $$\nu ^{(n)}(p)\rightarrow 1$$

ν

(
n
)

(
p
)

→
1

when $$p>0.45$$

p
>
0.45

. (Our method, in fact, shows that with some finer tuning the same is true for $$p>0.419533$$

p
>
0.419533

.)
Peopling Prehistoric Coastlines: Identifying Mid-Holocene Forager Settlement Strategies in Northern Norway
Authors: Damm Charlotte Brysting , Skandfer Marianne , Jordan Peter D. 
Published: December 2021

AbstractIn circumpolar regions, coastlines offer rich constellations of diverse resources and have long been a focus of human habitation. Despite the rich archaeological records that are located along many northern coastlines, there is a relatively limited understanding of the range of factors that informed local settlement strategies. Northern Norway has one of the world’s longest and best-preserved archaeological records of coastal habitation due to post-glacial uplift. Occupation begins in the early Holocene and appears to peak in the mid-Holocene. Our aim in this paper is to investigate the constraints and opportunities that informed the mid-Holocene settlement patterns, between c. 5000 and 0 BC. We present new data that were generated by intensive field surveys and undertake a qualitative multi-scalar analysis of site-locational choices, evaluating the influences of geography, topography and seasonal resource availability. Having identified stretches of the rugged coast as uninhabitable, we proceeded with analyses of the rest of the coastline. Our results indicate that all major settlements were sited to provide safe boat landing, good vantage points and shelter from storms. From these habitation sites, boat technology would have provided flexible access to diverse resources that were available throughout the year, and within a limited travel radius. We also demonstrate that these settlement strategies contrast with the way that the same coastlines were inhabited by pioneering groups in the early Holocene but appear to have some similarities with mid-Holocene coastal settlement patterns in Newfoundland and the Aleutian Islands. Overall, our results suggest that the multiple resources available along northern coastlines often enabled populations to occupy relatively localized areas for long periods. Longer-range mobility and interaction may instead have been primarily driven by socio-political factors rather than subsistence needs.
Effective prediction of lost circulation from multiple drilling variables: a class imbalance problem for machine and deep learning algorithms
Authors: Wood David A. , Mardanirad Sajjad , Zakeri Hassan 
Published: December 2021

AbstractMultiple machine learning (ML) and deep learning (DL) models are evaluated and their prediction performance compared in classifying five wellbore fluid-loss classes from a 20-well drilling dataset (Azadegan oil field, Iran). That dataset includes 65,376 data records with seventeen drilling variables. The dataset fluid-loss classes are heavily imbalanced (> 95% of data records belong to the less significant loss classes 1 and 2; only 0.05% of the data records belong to the complete-loss class 5). Class imbalance and the lack of high correlations between the drilling variables and fluid-loss classes pose challenges for ML/DL models. Tree-based and data matching ML algorithms outperform DL and regression-based ML algorithms in predicting the fluid-loss classes. Random forest (RF), after training and testing, makes only 35 prediction errors for all data records. Consideration of precision recall and F1-scores and expanded confusion matrices show that the RF model provides the best predictions for fluid-loss classes 1 to 3, but that for class 4 Adaboost (ADA) and class 5 decision tree (DT) outperform RF. This suggests that an ensemble of the fast to execute RF, ADA and DT models may be the best way to practically achieve reliable wellbore fluid-loss predictions. DL models underperform several ML models evaluated and are particularly poor at predicting the least represented classes 4 and 5. The DL models also require much longer execution times than the ML models, making them less attractive for field operations that require prompt information regarding rapid real-time decision responses to pending class-4 and class-5 fluid-loss events.
Fishermen’s perceptions and experiences toward the impact of climate change and anthropogenic activities on freshwater fish biodiversity in Côte d’Ivoire
Authors: Amoutchi Amien Isaac , Mehner Thomas , Ugbor Ogechi Nnabuchi , Kargbo Alpha , Paul Kouamelan Essetchi 
Published: December 2021

AbstractAfrica’s freshwater ecosystems are impacted by many threats due to climate change and several anthropogenic activities. In Côte d’Ivoire, the economy relies mostly on agriculture, which covers around 64% of the land surface. The study aimed to investigate Côte d’Ivoire fishermen’s perception of climate change, its drivers and other anthropogenic activities impacting freshwater fish biodiversity. The fish species locally threatened in the Ivorian freshwater ecosystems were also investigated. Face to face interviews and a structured questionnaire were used. The data obtained were analysed using descriptive statistics such as frequency, percentage, means, and standard deviation, minimum and maximum. The multinomial logit regression was also applied to test factors that influence fishermen’s awareness and perception of climate change and their perception of change in fish abundance. The results show that around 72.7% of fishermen were aware of climate change. Decreases of precipitation (87.9%) and increases of temperature (76.1%) were observed by fishermen. Also, a significant decrease in fish quantity was observed by respondents. Climate change and anthropogenic activities such as gold mining, water withdrawal, use of small-mesh fishing nets, overfishing, industrial waste pollution, pesticides use for agricultural purposes along watersheds, obnoxious fishing practices and population growth, were highlighted as the main reasons for this decline. Species such as Lates niloticus, Heterotis niloticus, Parachanna obscura, Malapterurus electricus, Sarotherodon galilaeus, Tilapia zillii, Polpyterus endlicheri and Labeo coubie were listed by fishermen as locally threatened within Ivorian freshwater ecosystems. Actions and policies are needed to be taken by local authorities to ensure the sustainability of fisheries resources. The information obtained from this study constitutes a prerequisite for developing and implementing studies or policies aimed at mitigating and combating the negative effect of climate change and anthropogenic activities on the Ivorian freshwater ecosystem.
The association between falls and autonomy in older adults is mediated by self-efficacy
Authors: Imani Hadis , Godde Ben 
Published: December 2021

Abstract
Objective
Falling has various physical and psychological consequences in older adults. We aimed at replicating previous findings that reported autonomy is associated with a history of falls and that this association is moderated by self-efficacy. We further assumed that cognitive function would moderate this relationship.

Method
We analyzed data from the German Ageing Survey (“Deutscher Alterssurvey,” DEAS, year 2017, n = 6626), a longitudinal cohort-based survey of individuals living in private households aged 40 and over in Germany.

Results
Linear regression confirmed that perceived autonomy was negatively associated with a history of falls. With higher self-efficacy, the association between falls and autonomy was less substantial. Further, we extend previous findings in that self-efficacy also mediated the effect of falls on perceived autonomy. Against our assumptions, cognition as measured with the digit-symbol substitution test predicted perceived autonomy but did not moderator this association.

Discussion
We conclude that interventions facilitating self-efficacy might ameliorate negative effects of falling on autonomy of older adults.
Water flow through sediments and at the ice-sediment interface beneath Sermeq Kujalleq (Store Glacier), Greenland
Authors: Doyle Samuel H. , Hubbard Bryn , Christoffersen Poul , Law Robert , Hewitt Duncan R. , Neufeld Jerome A. , Schoonman Charlotte M. , Chudley Thomas R. , Bougamont Marion 
Published: December 2021

AbstractSubglacial hydrology modulates basal motion but remains poorly constrained, particularly for soft-bedded Greenlandic outlet glaciers. Here, we report detailed measurements of the response of subglacial water pressure to the connection and drainage of adjacent water-filled boreholes drilled through kilometre-thick ice on Sermeq Kujalleq (Store Glacier). These measurements provide evidence for gap opening at the ice-sediment interface, Darcian flow through the sediment layer, and the forcing of water pressure in hydraulically-isolated cavities by stress transfer. We observed a small pressure drop followed by a large pressure rise in response to the connection of an adjacent borehole, consistent with the propagation of a flexural wave within the ice and underlying deformable sediment. We interpret the delayed pressure rise as evidence of no pre-existing conduit and the progressive decrease in hydraulic transmissivity as the closure of a narrow (< 1.5 mm) gap opened at the ice-sediment interface, and a reversion to Darcian flow through the sediment layer with a hydraulic conductivity of ≤ 10−6m s−1. We suggest that gap opening at the ice-sediment interface deserves further attention as it will occur naturally in response to the rapid pressurisation of water at the bed.
Three Solar Irradiance Proxies for Aperture Photoelectron Detections in Top‐Hat ESAs Coated With Ebonol‐C
Authors: da Silva D. , Gershman D. , Barrie A. , Elkington S. , Li X. , Kirk M. , Giles B. , Avanov L. , Shuster J. , Paterson B. , Schiff C. , Chen L. J. 
Published: December 2021

AbstractDecades after the introduction of top‐hat electrostatic analyzers (ESAs) to experimental space plasma physics, photoelectron noise in apertures of low‐energy electron instruments continues to be an issue in instrument performance. The photoelectrons at each portion of measured phase space distribution can be mapped through laboratory and in‐flight testing, and have been for many missions. In flight, the photoelectrons are a response to dynamic solar EUV spectral intensities which vary over the course of a solar cycle and even within a solar rotation. This paper outlines three solar irradiance proxies that can be used to scale a map of photo‐electron locations in phase space in order to account for dynamic solar activity. These proxies apply to top‐hat ESAs coated with Ebonol‐C (the most common coating) used by missions such as MMS, Solar Orbiter, the Van Allen Probes, and Juno. These proxies are discovered by searching possible wavelengths for correlation with an independent algorithm for MMS/FPI (Magnetospheric Multiscale Mission/Fast Plasma Instrument) which automatically determines the scaling factor. The three wavelengths that serve as viable proxies are found to be: 17.5, 30.5, and 37.5 nm.
Effects of Electron Precipitation on E‐Region Instabilities: Theoretical Analysis
Authors: Dimant Y. S. , Khazanov G. V. , Oppenheim M. M. 
Published: December 2021

AbstractDuring periods of strong geomagnetic activity, intense currents and electric fields originating in the magnetosphere inundate the high‐latitude E‐region ionosphere. These strong electric fields drive plasma instabilities, including the Farley‐Buneman instability (FBI). These instabilities give rise to small‐scale plasma turbulence that modifies the large‐scale ionospheric conductance that, in turn, affects the evolution of the magnetosphere‐ionosphere‐thermosphere system. Also, during geomagnetic storms, high‐energy precipitating electrons, ≳5 keV, frequently penetrate down to the same regions where the intense currents and electric fields exist. This research examines the effects of precipitating electrons on the generation of the FBI and shows that, under many common conditions, it can easily suppress the FBI in a predictable manner. We demonstrate that the plasma pressure of superthermal electrons may significantly exceed the regular plasma pressure of the cold ionospheric plasma. This effect will increase the FBI threshold and suppress the instability in auroral regions. However, our detailed theoretical analysis shows that the effect of the superthermal precipitating electrons on the FBI threshold is much stronger than the pressure effect. The energy dependence of the electron‐N2 collision frequency can greatly enhance the effect of this additional pressure, further suppressing the FBI, even at a moderate precipitation level. Therefore, we expect that precipitation will exert an additional significant feedback on the magnetosphere by preventing the elevated conductivity caused by FBI driven turbulence. Both the turbulence‐enhanced conductivities and this suppression should be taken into account in global modeling of the magnetosphere‐ionosphere coupling.
The Jovian Ionospheric Alfvén Resonator and Auroral Particle Acceleration
Authors: Lysak R. L. , Song Y. , Elliott S. , Kurth W. , Sulaiman A. H. , Gershman D. 
Published: December 2021

AbstractThe ionospheric Alfvén resonator (IAR) is a structure formed by the rapid decrease in the plasma density above a planetary ionosphere. This results in a corresponding increase in the Alfvén speed that can provide partial reflection of Alfvén waves. At Earth, the IAR on auroral field lines is associated with the broadband acceleration of auroral particles, sometimes termed the Alfvénic aurora. This arises since phase mixing in the IAR reduces the perpendicular wavelength of the Alfvén waves, which enhances the parallel electric field due to electron inertia. This parallel electric field fluctuates at frequencies of 0.1–20.0 Hz, comparable to the electron transit time through the acceleration region, leading to the broadband acceleration. The prevalence of such broadband acceleration at Jupiter suggests that a similar process can occur in the Jovian IAR. A numerical model of Alfvén wave propagation in the Jovian IAR has been developed to investigate these interactions, indicating that the IAR resonant frequencies are in the same range as those at Earth. This model describes the evolution of the electric and magnetic fields in the low‐altitude region close to Jupiter that is sampled during Juno's perijove passes. In particular, the model relates measurement of magnetic fields below the ion cyclotron frequency from the MAG and Waves instruments on Juno and electric fields from Waves to the associated parallel electric fields that can accelerate auroral particles.
Centennial‐ and Orbital‐Scale Erosion Beneath the Greenland Ice Sheet Near Jakobshavn Isbræ
Authors: Balter‐Kennedy A. , Young N. E. , Briner J. P. , Graham B. L. , Schaefer J. M. 
Published: December 2021

AbstractErosion beneath glaciers and ice sheets is a fundamental Earth‐surface process dictating landscape development, which in turn influences ice‐flow dynamics and the climate sensitivity of ice masses. The rate at which subglacial erosion takes place, however, is notoriously difficult to observe because it occurs beneath modern glaciers in a largely inaccessible environment. Here, we present (a) cosmogenic‐nuclide measurements from bedrock surfaces with well constrained exposure and burial histories in front of Jakobshavn Isbræ in western Greenland to quantify centennial‐scale erosion rates since ∼1850 CE, and (b) a new method combining cosmogenic‐nuclide measurements in a shallow bedrock core with cosmogenic‐nuclide modeling to determine orbital‐scale erosion rates across the same landscape. Twenty‐seven 10Be measurements in surficial bedrock constrain the erosion rate during historical times to 0.4–0.8 mm yr−1. Seventeen 10Be measurements in a 4‐m‐long bedrock core yield a centennial‐scale erosion rate of 0.3–0.6 mm yr−1, corroborating the results from our surface samples, and reveal that 10Be concentrations below ∼2 m depth are greater than what is predicted by an idealized production‐rate depth profile. We utilize this excess 10Be at depth to constrain orbital‐scale erosion rates at Jakobshavn Isbræ to 0.1–0.3 mm yr−1. The broad similarity between centennial‐ and orbital‐scale erosion rates suggests that subglacial erosion rates have remained relatively uniform throughout the Pleistocene adjacent to Jakobshavn Isbræ.
Leakages suppression by isolating the desired quantum levels for high-temperature terahertz quantum cascade lasers
Authors: Wang Li , Lin Tsung-Tse , Chen Mingxi , Wang Ke , Hirayama Hideki 
Published: December 2021

AbstractThe key challenge for terahertz quantum cascade lasers (THz-QCLs) is to make it operating at room-temperature. The suppression of thermally activated leakages via high lying quantum levels is emphasized recently. In this study, we employ the advanced self-consistent method of non-equilibrium Green’s function, aiming to reveal those kinds of leakages in the commonly used THz-QCL designs based on 2-, 3- and 4-quantum well. At the high temperature of 300 K, if all the confined high lying quantum levels and also the continuums are included within three neighboring periods, leakages indeed possess high fraction of the total current (21%, 30%, 50% for 2-, 3- and 4-quantum well designs, respectively). Ministep concept is introduced to weaken those leakage channels by isolating the desired levels from high lying ones, thus the leakages are well suppressed, with corresponding fractions less than 5% for all three designs.
Novel cancer subtyping method based on patient-specific gene regulatory network
Authors: Nakazawa Mai Adachi , Tamada Yoshinori , Tanaka Yoshihisa , Ikeguchi Marie , Higashihara Kako , Okuno Yasushi 
Published: December 2021

AbstractThe identification of cancer subtypes is important for the understanding of tumor heterogeneity. In recent years, numerous computational methods have been proposed for this problem based on the multi-omics data of patients. It is widely accepted that different cancer subtypes are induced by different molecular regulatory networks. However, only a few incorporate the differences between their molecular systems into the identification processes. In this study, we present a novel method to identify cancer subtypes based on patient-specific molecular systems. Our method realizes this by quantifying patient-specific gene networks, which are estimated from their transcriptome data, and by clustering their quantified networks. Comprehensive analyses of The Cancer Genome Atlas (TCGA) datasets applied to our method confirmed that they were able to identify more clinically meaningful cancer subtypes than the existing subtypes and found that the identified subtypes comprised different molecular features. Our findings also show that the proposed method can identify the novel cancer subtypes even with single omics data, which cannot otherwise be captured by existing methods using multi-omics data.