Search results for "Classification"

Alleviating Class Imbalance Problem in Automatic Sleep Stage Classification

2022

For real-world automatic sleep-stage classification tasks, various existing deep learning-based models are biased toward the majority with a high proportion. Because of the unique sleep structure, most of the current polysomnography (PSG) datasets suffer an inherent class imbalance problem (CIP), in which the number of each sleep stage is severely unequal. In this study, we first define the class imbalance factor (CIF) to describe the level of CIP quantitatively. Afterward, we propose two balancing methods to alleviate this problem from the dataset quantity and the relationship between the class distribution and the applied model, respectively. The first one is to employ the data augmentati…

Partially disarticulated new Miocene burrower bug (Hemiptera: Heteroptera: Cydnidae) from Cerová (Slovakia) documents occasional preservation of terr…

2015

The state of preservation of the bug Sehirus carpathiensis J.A. Lis, Vršanský & Schlögl, sp. n. (Hemiptera: Heteroptera: Cydnidae) from the Lakšárska Nová Ves Formation at Cerová (Slovakia) supports extremely rapid sinking and burial in upper bathyal Early Miocene sediments. The specimen originated from land at most a few kilometers away, but transport via a river can be excluded as the head and wings are still attached. Its most likely source based on fossil flora and the habitat of several living representatives of the genus is a riparian habitat in an adjacent area of land. Phylogenetically the new species is closely related to both Oligocene and living representatives of the genus, thus…

Low‐Valent Germanylidene Anions: Efficient Single‐Site Nucleophiles for Activation of Small Molecules

2021

Abstract Rare mononuclear and helical chain low‐valent germanylidene anions supported by cyclic (alkyl)(amino)carbene and hypermetallyl ligands were synthesised by stepwise reduction from corresponding germylene precursors via stable and isolable germanium radicals. The electronic structures of the anions can be described with ylidene and ylidone resonance forms with the Ge−C π‐electrons capable of binding even weak electrophiles. The germanylidene anions reacted with CO2 to give μ‐CO2‐κC:κO complexes, a rare coordination mode for low‐valent germanium and inaccessible for the related neutral germylones. These results implicate low‐valent germanylidene anions as efficient single‐site nucleop…

Assessing the quality of dissolved organic matter in forest soils using ultraviolet absorption spectrophotometry

2007

Abbreviations: DOC, dissolved organic carbon; SUVA, specifi c ultraviolet absorbance; UV, ultraviolet. Ultraviolet spectrophotometry was used to investigate the effects, 30 yr after planting, of tree species substitution on the aromatic C content and related properties of dissolved organic carbon (DOC). Precautions were taken to correct measurements for the absorbance of NO 3 and dissolved Fe. In litter leachates, a signifi cant reduction in the aromatic content of DOC was found in the Douglas-fi r [Pseudotsuga menziesii (Mirb.) Franco] plantation but not in the beech (Fagus sylvatica L.) plantation. The disturbance of short-term C dynamics thus revealed agreed well with fi eld observations…

Synthesis and Biological Evaluation of a Multiantigenic Tn/TF-Containing Glycopeptide Mimic of the Tumor-Related MUC1 Glycoprotein

2006

Combined Use of Structure Analysis, Studies of Molecular Association in Solution, and Molecular Modelling to Understand the Different Propensities of…

2021

The arrangement of hydroxyl groups in the benzene ring has a significant effect on the propensity of dihydroxybenzoic acids (diOHBAs) to form different solid phases when crystallized from solution. All six diOHBAs were categorized into distinctive groups according to the solid phases obtained when crystallized from selected solvents. A combined study using crystal structure and molecule electrostatic potential surface analysis, as well as an exploration of molecular association in solution using spectroscopic methods and molecular dynamics simulations were used to determine the possible mechanism of how the location of the phenolic hydroxyl groups affect the diversity of solid phases formed…

bbFISH-ing in the sonication fluid

2019

Abstract By 2030, the annual number of combined total hip and knee arthroplasty is estimated to reach 3.5 to 4 million in the US alone. In the context of a constant increase of the number of primary and revision total hip and knee arthroplasty, an increased risk of complication is expected. Prosthetic joint infections (PJIs) represent major cause of healthcare expenditure and morbidity. PJI still remain the most common and feared arthroplasty complication. A rapid and correct diagnosis of infection is decisive for a correct therapeutical management. In this setting, the Academic Emergency Hospital Sibiu adopted and implemented, with the beginning of September 2016, a new strategy for the di…

Sonication-Induced Modification of Carbon Nanotubes: Effect on the Rheological and Thermo-Oxidative Behaviour of Polymer-Based Nanocomposites.

2018

The aim of this work is the investigation of the effect of ultrasound treatment on the structural characteristics of carbon nanotubes (CNTs) and the consequent influence that the shortening induced by sonication exerts on the morphology, rheological behaviour and thermo-oxidative resistance of ultra-high molecular weight polyethylene (UHMWPE)-based nanocomposites. First, CNTs have been subjected to sonication for different time intervals and the performed spectroscopic and morphological analyses reveal that a dramatic decrease of the CNT's original length occurs with increased sonication time. The reduction of the initial length of CNTs strongly affects the nanocomposite rheological behavio…

Evaluation of the Behavior of Phenolic Compounds and Steviol Glycosides of Sonicated Strawberry Juice Sweetened with Stevia (Stevia rebaudiana Berton…

2019

In this study, the influence of stevia addition and sonication processing parameters on the phenolic content and profile as well as the steviol glycosides of strawberry juice-based samples was investigated. For this purpose, three matrices&mdash

The adaptations to tube-dwelling life of Propsilocerus akamusi (Diptera: Chironomidae) larvae and its eutrophication-tolerant mechanisms

2019

Propsilocerus akamusi (Diptera: Chironomidae) is a dominant macroinvertebrate species in many eutrophic lakes in subtropical and temperate zones. P. akamusi larvae can migrate deep into the sediment (>30 cm) during summer where is no oxygen. However, to our knowledge, the specific adaptive tactics of its tube-dwelling life (>30 cm) and underlying mechanisms why this species is favored by nutrient-rich lakes remain limited. With the understanding above-mentioned issues, we can provide important information for the development of sensitive biomonitoring. We examined monthly morphological dynamics and physiological adaptations of P. akamusi to anoxic conditions, and environmental relationships…