bluuebunny/crossref_metadata_2025 huggingface dataset:
Automatic Selection of Four-Bar Linkage Designs for Path Generation Task
Authors: Kota S. , Gudapati R. B.
Published: April 2021

Often a simple mechanism to trace a desired path is sought. Coupler curves of linkages are generally difficult to determine, especially in the case that a certain shape or a type of curve is required for a particular application. Precision point techniques do not guarantee that the desired path will be generated. The design methodology presented in this paper is an indirect synthesis approach to design four-bar linkages that trace (approximately) a given desired path. Simple and yet extremely useful design charts for the initial selection of four-bar linkage candidate designs are presented in this paper. This is based on our philosophy that an arbitrary path (desired) can be viewed as an approximation to a known symmetrical path. Four-bar linkages that generate symmetrical paths are easier to design and exhibit a definite pattern of changes in their shape as the linkage parameters are varied. The first step in automating the design-selection process requires a satisfactory means to quantitatively compare the desired with the known (symmetrical) coupler curves. This paper addresses various issues involved in the comparison of two arbitrary curves. Based on curve parametrization, an effective algorithm for quantitative shape evaluation of arbitrary curves is developed. Finally, the design charts and design examples are presented.
Robot Accuracy Qualification: A Stochastic Differential Kinematic Monte Carlo Error Combination Approach
Authors: Sturm A. J. , Lee M.-Y.
Published: April 2021

This paper presents a stochastic model and a Monte Carlo computer simulation algorithm to combine all measurable non-linear kinematic and misalignment error components to predict the overall tooltip quasi-static robot spatial position accuracy for a gantry robot. These errors include joint position accuracies, joint misalignments, joint zero position offsets, axis directional straightness, squareness errors and kinematic coupling errors. All of these errors can be independently measured using a laser interferometer and/or other precision measuring instruments. The interation between robot joints and coupling between these error components are very complex making the determination of the overall robot spatial position accuracy difficult. In this paper a Monte Carlo computer simulation program for predicting overall robot spatial position accuracy based on a stochastic error model was developed. Finally, simulation results are compared with direct spatial accuracy test results using a computerized Theodolite system. This robot spatial accuracy qualification methodology has been accepted and recommended by RIA as part of American National Standard for robot accuracy evaluation.
A First Class of Computational Tools for Preliminary Engineering Design
Authors: Wood K. L. , Antonsson E. K.
Published: April 2021

Preliminary engineering design intrinsically consists of imprecise descriptions of the input parameters. We present new conceptual and algorithmic procedures for dealing with such imprecise descriptions. Specifically, a two-part method is outlined for performing design calculations on these “fuzzy” parameters, as well as determining a measure for the parameters’ coupling. By interpreting the input set of variables for preliminary design in terms of fuzzy sets, we demonstrate how the engineer may associate his subjective meaning with the input parameters and the output functional requirement, leading to the foundation of our approach. An example of the method highlights the primary issues and the implementation scheme as a computational tool.
Dutch studies bring back the fun—but are they good science?
Authors: de Vrieze Jop
Published: April 2021

Critics question protocols and ethics of experimental gatherings that rely on testing to keep people safe.
The sentinels
Authors: Grossman Dan
Published: April 2021

In Brazil, a team of scientists watches the world's largest rainforest for pathogens that could spill from animals to people.
Equids engineer desert water availability
Authors: Lundgren Erick J. , Ramp Daniel , Stromberg Juliet C. , Wu Jianguo , Nieto Nathan C. , Sluk Martin , Moeller Karla T. , Wallach Arian D.
Published: April 2021

Digging for water

Water is scarce in dryland ecosystems. Some larger animals in these regions dig wells that may provide water to other species. This behavior may have been common among megafauna that are now extinct, especially in North and South America, where megafaunal extinctions were the most severe. Lundgren
et al.
tested whether feral equids (horses and donkeys) reintroduced to desert regions in the North American southwest dig wells that provide ecosystem-level benefits. They found that equid-dug wells increased water availability, were used by a large number of species, and decreased distance between water sources. Abandoned wells also led to increased germination in key riparian tree species. Such equid-dug wells improve water availability, perhaps replacing a lost megafaunal function.

Science
, this issue p.
491
Toxin-antitoxin RNA pairs safeguard CRISPR-Cas systems
Authors: Li Ming , Gong Luyao , Cheng Feiyue , Yu Haiying , Zhao Dahe , Wang Rui , Wang Tian , Zhang Shengjie , Zhou Jian , Shmakov Sergey A. , Koonin Eugene V. , Xiang Hua
Published: April 2021

Small RNAs guard CRISPR-Cas

The microbial adaptive immunity system CRISPR-Cas benefits microbes by warding off genetic invaders, but it also inflicts a fitness cost because of occasional autoimmune reactions, rendering CRISPR loci evolutionarily unstable. Li
et al.
identified previously unnoticed toxin-antitoxin RNA pairs embedded within diverse CRISPR-Cas loci. The antitoxin RNA mimics a CRISPR RNA and repurposes the CRISPR immunity effector to transcriptionally repress a toxin RNA that would otherwise arrest cell growth by sequestering a rare transfer RNA. These small RNAs thus form a symbiosis with CRISPR, rendering CRISPR addictive to the host despite its fitness cost. These findings reveal how CRISPR-Cas can operate as a selfish genetic element.

Science
, this issue p.
eabe5601
Supplemental Material: Regional chronostratigraphic synthesis of the Cenomanian-Turonian Oceanic Anoxic Event 2 (OAE2) interval, Western Interior Basin (USA): New Re-Os chemostratigraphy and 40Ar/39Ar geochronology
Authors: Jones Matthew M. , al. et
Published: April 2021

(1) Complete Ar geochronology data, bentonite correlations, and collection in Kaiparowits Plateau, Cenomanian-Turonian boundary age calculations, core photos and description of hiatuses, and Angus Core depth scale alignment correction. (2) Time scale tables for cores.
Respectful care an added extra: a grounded theory study exploring intrapartum experiences in Zambia and Tanzania
Authors: Lavender Tina , Bedwell Carol , Kasengele Chowa Tembo , Kimaro Debora , Kuzenza Flora , Lyangenda Kutemba , Mills Tracey A , Nsemwa Livuka , Shayo Happiness , Tuwele Khuzuet , Wakasiaka Sabina , Laisser Rose
Published: April 2021

Background

Quality of maternal and newborn care is integral to positive clinical, social and psychological outcomes. Respectful care is an important component of this but is suboptimum in many low-income settings. A renewed energy among health professionals and academics is driving an international agenda to eradicate disrespectful health facility care around the globe. However, few studies have explored respectful care from different vantage points.

Methods

We used Strauss and Corbin’s grounded theory methodology to explore intrapartum experiences in Tanzania and Zambia. In-depth interviews were conducted with 98 participants (48 women, 18 partners, 21 health-providers and 11 key stakeholders), resulting in data saturation. Analysis involved constant comparison, comprising three stages of coding: open, axial and selective. The process involved application of memos, reflexivity and positionality.

Results

Findings demonstrated that direct and indirectsocial discriminationled to inequity of care. Health-providers were believed to displaymanipulative behavioursto orchestrate situations for their own or the woman’s benefit, and were oftencaring against the odds, in challenging environments. Emergent categories were related to the core category:respectful care, an added extra, which reflects the notion that women did not always expect or receive respectful care, and tolerated poor experiences to obtain services believed to benefit them or their babies. Respectful care was not seen as a component of good quality care, but a luxury that only some receive.

Conclusion

Both quality of care and respectful care were valued but were not viewed as mutually inclusive. Good quality treatment (transactional care) was often juxtaposed with disrespectful care; with relational care having a lower status among women and healthcare providers. To readdress the balance, respectful care should be a predominant theme in training programmes, policies and audits. Women’s and health-provider voices are pivotal to the development of such interventions.
Depression, anxiety and psychological distress in patients with pulmonary hypertension: a mixed-methods study
Authors: Takita Yuka , Takeda Yuko , Fujisawa Daisuke , Kataoka Masaharu , Kawakami Takashi , Doorenbos Ardith Z
Published: April 2021

Introduction

Pulmonary hypertension (PH) is a chronic and progressive disease. While prognoses have improved, PH patients still experience side effects and activity restrictions. Accordingly, the key questions asked by this study are ‘How many PH patients have depression/anxiety symptoms?’ and ‘Is there a difference in the symptoms and distress factors between pulmonary arterial hypertension (PAH) and chronic thromboembolic PH (CTEPH) patients, and how are they experiencing distress?’

Methods

A mixed-methods study was conducted to collect and analyse quantitative and qualitative data. We administered questionnaires (Patient Health Questionnaire (PHQ-9) and Generalised Anxiety Disorder-7) and then conducted interviews with participants who reported moderate to severe depressive symptoms (PHQ-9 ≥10).

Results

Seventy-four participants were enrolled in the study, 25 with idiopathic PAH and 49 with CTEPH. Their average age was 55.2 years (PAH 42.7 years, CTEPH 61.5 years). Overall, 44.6% of participants had mild or more severe depressive symptoms (PHQ-9 ≥5) and 17.6% had moderate or more severe depressive symptoms (PHQ-9 ≥10). PAH patients had particularly high depressive symptoms (PHQ-9 ≥5: PAH 64.0%, CTEPH 34.7%; PHQ-9 ≥10: PAH 24%, CTEPH 14.3%). We extracted four common themes from the qualitative interview data on participants’ experience of psychological distress: ‘Loss of myself,’ ‘Isolation from my surroundings,’ ‘Hassle associated with oxygen therapy,’ and ‘Fear of illness progression/deterioration.’ One theme— ‘Suffering from side effects’—was extracted only for PAH patients, while another—‘Rumination on illness due to breathlessness’—was extracted only for CTEPH patients.

Discussion and conclusion

The study found that PH patients are prone to depression. The identification of factors and themes that influence the psychological distress of PH patients is important information that can be used to improve the support for the physical and mental health of these patients. Interventions for these distress may contribute to improving the mental status of PH patients.
Image-guided placement of totally implanted vascular access device: retrospective analysis of the clinical outcomes and associated risk factors
Authors: Yoon So Yeon , Jeon Gyeong Sik , Jung Sanghoon
Published: April 2021

Objectives

To determine risk factors for catheter survival and complications after image-guided implantation of a totally implanted vascular access device (TIVAD).

Methods

A total of 2883 TIVADs (2735 patients, 63.5±13 years old, 1060 men, 1675 women) implanted under guidance by ultrasound and fluoroscopy in our institution from January 2010 to December 2019 were evaluated retrospectively. We used the log rank test and logistic regression to analyse risk factors associated with catheter survival and complications.

Results

Female patients (n=1778; 61.7%; mean catheter survival days: 780.6 days) and those with a haematological malignancy (n=277; 10.1%; mean catheter survival days: 1019 days) had significantly better catheter survival than male patients (n=1105; 38.3%; mean catheter survival days: 645.9 days) and those with a solid organ malignancy (n=2447; 89.5%; mean catheter survival days: 701 days) (p<0.001 and p=0.003). Patients with haematological malignancies and benign vascular inflammatory disease (n=11; 0.4%) were vulnerable to infection (n=96; 3.3%) (p<0.001 and p=0.004). Thrombotic malfunction (n=38; 1.3%) was significantly more common in females than males (p=0.005). Non-thrombotic malfunction (n=16; 0.6%) showed a significant association with left positioning of the TIVAD (n=410; 14.2%) (p=0.043). Wound dehiscence (n=3; 0.1%) was significantly more frequent in punctured veins other (n=23; 0.8%) than the internal jugular vein (p<0.001).

Conclusions

Increased attention should be paid to patients with an underlying haematological malignancy, underlying vascular inflammatory disease, female patients, older patients, those accessed via a vein other than the IJV, those with left positioning of the TIVAD system or those with a prolonged TIVAD maintenance.
Time to get serious about the detection and monitoring of early lung disease in cystic fibrosis
Authors: Bayfield Katie J , Douglas Tonia A , Rosenow Tim , Davies Jane C , Elborn Stuart J , Mall Marcus , Paproki Anthony , Ratjen Felix , Sly Peter D , Smyth Alan R , Stick Stephen , Wainwright Claire E , Robinson Paul D
Published: April 2021

Structural and functional defects within the lungs of children with cystic fibrosis (CF) are detectable soon after birth and progress throughout preschool years often without overt clinical signs or symptoms. By school age, most children have structural changes such as bronchiectasis or gas trapping/hypoperfusion and lung function abnormalities that persist into later life. Despite improved survival, gains in forced expiratory volume in one second (FEV1) achieved across successive birth cohorts during childhood have plateaued, and rates of FEV1decline in adolescence and adulthood have not slowed. This suggests that interventions aimed at preventing lung disease should be targeted to mild disease and commence in early life. Spirometry-based classifications of ‘normal’ (FEV1≥90% predicted) and ‘mild lung disease’ (FEV170%–89% predicted) are inappropriate, given the failure of spirometry to detect significant structural or functional abnormalities shown by more sensitive imaging and lung function techniques. The state and readiness of two imaging (CT and MRI) and two functional (multiple breath washout and oscillometry) tools for the detection and monitoring of early lung disease in children and adults with CF are discussed in this article.

Prospective research programmes and technological advances in these techniques mean that well-designed interventional trials in early lung disease, particularly in young children and infants, are possible. Age appropriate, randomised controlled trials are critical to determine the safety, efficacy and best use of new therapies in young children. Regulatory bodies continue to approve medications in young children based on safety data alone and extrapolation of efficacy results from older age groups. Harnessing the complementary information from structural and functional tools, with measures of inflammation and infection, will significantly advance our understanding of early CF lung disease pathophysiology and responses to therapy. Defining clinical utility for these novel techniques will require effective collaboration across multiple disciplines to address important remaining research questions. Future impact on existing management burden for patients with CF and their family must be considered, assessed and minimised.

To address the possible role of these techniques in early lung disease, a meeting of international leaders and experts in the field was convened in August 2019 at the Australiasian Cystic Fibrosis Conference. The meeting entitiled ‘Shaping imaging and functional testing for early disease detection of lung disease in Cystic Fibrosis’, was attended by representatives across the range of disciplines involved in modern CF care. This document summarises the proceedings, key priorities and important research questions highlighted.
Beyond the COVID-19 crisis: building on lost opportunities in the history of public health
Authors: Jones Esyllt , MacDougall Heather , Monnais Laurence , Hanley James , Carstairs Catherine
Published: April 2021

The influenza pandemic of 1918–1920, which killed 50 000 Canadians, spurred the creation of a federal department of public health. But in the intervening century, public health at all levels has remained, as Marc Lalonde put it in 1988, the “poor cousin” in the health care system ( Lalonde 1988 , p. 77). Punctuated by sporadic investment during infectious disease crises, such as polio in the early 1950s, public health is less of a priority as the cost of tertiary health interventions rises. While public health potentially involves a broad range of interventions, this paper focuses on the history of public health interventions around infectious disease. COVID-19 has forced us to relearn the importance of maintaining basic infectious/communicable disease control capacity and revealed the cost of our failure to do so. It has also drawn our attention to the intersection between social inequality, racism, and colonialism and vulnerability to disease. In addition to investing in our capacity to contain disease outbreaks as they occur, we must plan now for how to achieve greater health equity in the future by addressing underlying economic and social conditions and providing meaningful access to preventive care for all. This is how we build a truly resilient society. Governments at all levels have recognized the importance of social factors in shaping health and illness for decades. But greater health equity will result only from genuine action on this knowledge. Action will arise from public advocacy in support of prevention, and a new level of engagement and collaboration between affected individuals and communities, public health experts, and governments.
An end-to-end statistical process with mobile network data for official statistics
Authors: Salgado David , Sanguiao Luis , Oancea Bogdan , Barragán Sandra , Necula Marian
Published: April 2021

Mobile network data has been proven to provide a rich source of information in multiple statistical domains such as demography, tourism, urban planning, etc. However, the incorporation of this data source to the routinely production of official statistics is taking many efforts since a diversity of highly entangled issues (access, methodology, IT tools, quality, skills) must be solved beforehand. To do this, one-off studies with concrete data sets are not enough and a standard statistical production process must be put in place. We propose a concrete modular process structured into evolvable modules detaching the strongly technological layer underlying this data source from the necessary statistical analysis producing outputs of interest. This architecture follows the principles of the so-called ESS Reference Methodological Framework for Mobile Network Data. Each of these modules deals with a different aspect of this data source. We apply hidden Markov models for the geolocation of mobile devices, use a Bayesian approach on this model to disambiguate devices belonging to the same individual, compute aggregate numbers of individuals detected by a telecommunication network using probability theory, and model hierarchically the integration of auxiliary information from the telco market and official data to produce final estimates of the number of individuals across different territorial regions in the target population. A first simple illustrative proposal has been applied to synthetic data providing preliminary software tools and accuracy indicators monitoring the performance of the process. Currently, this exercise has been applied to the estimation of present population and origin-destination matrices. We present an illustrative example of the execution of these production modules comparing results with the simulated ground truth, thus assessing the performance of each production module.
INVESTIGATION USING FINITE ELEMENT ANALYSIS OF EFFECT ON CRATER GEOMETRY OF DIFFERENT ABRASIVE TYPES IN ABRASIVE WATER JET MACHINING
Authors: GOK KADIR
Published: April 2021

Today, manufacturing methods are classified into two groups as conventional and non- conventional manufacturing methods. While turning, milling, and drilling are among the conventional manufacturing methods, processes such as laser, plasma, electro erosion, ultrasonic machining and water jet machining are among non-conventional, namely modern manufacturing methods. The cutting tool does not used in modern manufacturing methods. This situation is an advantage. There are some uncertainties on the machining performance of abrasive types, apart from the superior properties of the method. In this study, the effect of different abrasive types on machining performance in abrasive water jet machining (AWJM) was investigated by using computer aided finite element analysis.
Breaking of the Similarity Principle in Markov Generators of Low Density Limit Type and the Role of Degeneracies in the Landscape of Invariant States
Authors: Accardi L. , García-Corte J. C. , Guerrero-Poblete F. , Quezada R.
Published: April 2021

The similarity principle is an extension of the principle of thermal relaxation that naturally arises in the stochastic limit of quantum theory. We construct examples of Low Density Limit (LDL) generators, associated to an environment state in equilibrium at inverse temperature β, which admit non-(β, HS)-equilibrium states. We prove that in some cases, the attraction domain of the (β, HS)-equilibrium state is empty. This means that the similarity principle, in its original thermodynamical formulation, can be broken in the LDL limit. This result is obtained as a consequence of a more general phenomenon: the role of degeneracies in the spectrum of the Liouvillian of the system Hamiltonian associated to the generator. We start from the definition of LDL type generators given in [5] and we introduce a finer classification of these generators based on the above degeneracies. The simplest subclass, called 2-generic, is a nontrivial extension of the generators associated to the so-called Λ and V configurations, widely used in quantum optics and involving 2 levels of the system Hamiltonian. Since each 2-generic block involves 3 or 4 levels of the system Hamiltonian we expect that they can reveal some interesting new physical phenomenon, as it happened in the 2-level case. In the last section, we restrict our attention to a 3-level system with a Hamiltonian that is associated to a class of 2-generic LDL generators. Finally, we prove that, for some LDL generators in this class the statement formulated at the beginning holds true.
Real-Time Geometric Glint Anti-Aliasing with Normal Map Filtering
Authors: Chermain Xavier , Lucas Simon , Sauvage Basile , Dischler Jean-Michel , Dachsbacher Carsten
Published: April 2021

Real-time geometric specular anti-aliasing is required when using a low number of pixel samples and high-frequency specular lobes. Several methods have been proposed for mono-lobe bidirectional reflection distribution functions (BRDFs), but none for multi-lobe BRDFs, e.g., a glinty BRDF. We present the first method for real-time geometric glint anti-aliasing (GGAA). It eliminates most of the inconsistent appearing and disappearing of glints on surfaces with significant curvatures during animations. The technique uses the glinty BRDF of Chermain et al. [2020] and leverages hardware GPU-filtering of textures to filter slope distributions on the fly. We also improve this glinty BRDF by adding a correlation factor of slope. This BRDF parameter allows convergence to normal distribution functions that are not aligned on the surface's axes. Above all, this parameter makes glint rendering compatible with normal map filtering using LEAN mapping. Using GGAA increases the rendering time from 0.6 % to 4.2 % and it requires 1/3 more memory due to MIP mapping of tabulated slope distributions. The results are compared with references using a thousand samples per pixel.
FaceBlit
Authors: Texler Aneta , Texler Ondřej , Kučera Michal , Chai Menglei , Sýkora Daniel
Published: April 2021

We present FaceBlit---a system for real-time example-based face video stylization that retains textural details of the style in a semantically meaningful manner, i.e., strokes used to depict specific features in the style are present at the appropriate locations in the target image. As compared to previous techniques, our system preserves the identity of the target subject and runs in real-time without the need for large datasets nor lengthy training phase. To achieve this, we modify the existing face stylization pipeline of Fišer et al. [2017] so that it can quickly generate a set of guiding channels that handle identity preservation of the target subject while are still compatible with a faster variant of patch-based synthesis algorithm of Sýkora et al. [2019]. Thanks to these improvements we demonstrate a first face stylization pipeline that can instantly transfer artistic style from a single portrait to the target video at interactive rates even on mobile devices.
N-Doped Carbon Nanosheets from Biomass for Ultra Long-Cycling and High Energy Density Symmetric Supercapacitors
Authors: Kesavan Thangaian , Raaju Sundhar Arul Saravanan , Dharaneshwar Sasidharan , Prabu Natarajan , Manickam Sasidharan
Published: April 2021

The demand for high performance energy storage devices has stimulated much interests in developing high-energy density supercapacitors. Herein, we report N-doped peanut hull derived activated carbon (PHAC) nanosheets as high-performance supercapacitor electrode by low-cost approach. Electron microscope and physiochemical characterization of PHAC confirm multi-layered sheet like nanostructures with self-doped nitrogen. Tuning of KOH activation temperature in a narrow range between 700 °C and 750 °C has a significant effect over specific surface area which increases up to ∼2300 m2g−1for 720 °C activated PHAC compared to 501 m2g−1for 700 °C treated sample. Investigation of PHACs as supercapacitor electrode in 1.0 M H2SO4electrolyte delivers high capacitance of 195 Fg−1at an applied current density of 1 Ag−1with superior capacitance retention of 98.6% after 15000 cycles. More importantly, PHACs electrode shows high stability even at a current density of 50 Ag−1with an impressive capacitive retention of 49.2%. In a symmetric cell configuration, the PHAC constructed electrode shows a maximum power density of 25 KW kg−1with energy density of 8.96 Wh kg−1. Such an exquisite charge storage performance of N-doped peanut hull based carbon nanosheets is attributed to very large surface area, porosity, high N-content vis-ẚ-vis electrical conductivity.
The Role of Endothelial Mesenchymal Transformation on Infantile Hemangioma
Authors: Zhong Xin , Zheng Gang , Ding Min , Li Jing-Bing , Qian Qi-Hong
Published: April 2021

Objective. Infantile hemangioma (IH) is the most common infantile benign tumor derived from endothelial cells (ECs). The mechanism of IH degeneration into fibroadipose tissue is still unclear. We aimed to explore the effects of endothelial mesenchymal transformation (EndMT) on IH and explore its underlying mechanism. Methods. HemECs were treated with different concentrations of transforming growth factor-β1 (TGF-β1) as in vitro models. The CCK-8 assay was utilized to explore the effect of TGF-β1 on cell proliferation. Scratch test was conducted to determine the role of TGF-β1 in cell invasion. The influence of TGF-β1 on the E-cadherin, vimentin, N-cadherin, and LC3B expression in HemECs was detected by Western blot analysis. Expression of TGF-β1, E-cadherin, vimentin, N-cadherin, and LC3B in IH was determined by immunohistochemistry. Results. After TGF-β1 treatment, HemECs lost pebble-like morphology and presented fusiform or fibroblast-like appearance; the proliferation activity decreased significantly, endothelial cell markers decreased; interstitial markers increased, and autophagy protein expression increased. Immunohistochemical staining demonstrated higher positive expression rate of TGF-β1 and N-cadherin and poorer positive expression rate of E-cadherin related to proliferative tissues. In addition, compared with proliferative cells, the positive expression rate of E-cadherin in degenerated tissues was significantly increased, while the positive expression rate of N-cadherin was markedly reduced. Interestingly, the immunohistochemical results indicated that LC3B expression in the proliferative phase was lower than that in the regressive phase, whereas the expression of LC3B was significantly upregulated after hemangioma endothelial cells transformed into endothelial mesenchyme. Conclusion. TGF-β1 could induce EndMT in HemECs. TGF-β1 inhibited cell proliferation in a concentration-dependent manner and promoted autophagy and migration. Our investigation demonstrated that EndMT plays a significant role in the degradation of hemangioma, which provides an insight for the treatment of hemangioma.
Kernel Regression Residual Decomposition Method to Detect Rolling Element Bearing Faults
Authors: Wang Xiaoqian , Sheng Dali , Deng Jinlian , Zhang Wei , Cai Jie , Zhao Weisheng , Xiang Jiawei
Published: April 2021

The raw vibration signal carries a great deal of information representing the mechanical equipment's health conditions. However, in the working condition, the vibration response signals of faulty components are often characterized by the presence of different kinds of impulses, and the corresponding fault features are always immersed in heavy noises. Therefore, signal denoising is one of the most important tasks in the fault detection of mechanical components. As a time-frequency signal processing technique without the support of the strictly mathematical theory, empirical mode decomposition (EMD) has been widely applied to detect faults in mechanical systems. Kernel regression (KR) is a well-known nonparametric mathematical tool to construct a prediction model with good performance. Inspired by the basic idea of EMD, a new kernel regression residual decomposition (KRRD) method is proposed. Nonparametric Nadaraya–Watson KR and a standard deviation (SD) criterion are employed to generate a deep cascading framework including a series of high-frequency terms denoted by residual signals and a final low-frequency term represented by kernel regression signal. The soft thresholding technique is then applied to each residual signal to suppress noises. To illustrate the feasibility and the performance of the KRRD method, a numerical simulation and the faulty rolling element bearings of well-known open access data as well as the experimental investigations of the machinery simulator are performed. The fault detection results show that the proposed method enables the recognition of faults in mechanical systems. It is expected that the KRRD method might have a similar application prospect of EMD.
Hypercalcemia in Small Lymphocytic Lymphoma with an Elevated Parathyroid Hormone-Related Peptide Associated with Early Richter Transformation
Authors: Bains Ashish , Covas Pedro , Timofeeva Olga , Bromberg Michael
Published: April 2021

Hypercalcemia in malignancy is associated with multiple mechanisms and occurs in up to 20–30% of cancer patients. We report a case of small lymphocytic lymphoma/chronic lymphocytic leukemia (SLL/CLL) associated with hypercalcemia and an elevation in parathyroid hormone-related peptide (PTHrP) in the setting of a Richter transformation. Real-time reverse transcriptase PCR on lymph node biopsy specimens obtained before and after transformation showed an 8-fold increase in PTHrP mRNA levels and about 2-fold decrease in the levels of its cognate receptor PTHR1. The findings of this case suggest that parathyroid hormone-related peptide might be useful in monitoring a specific group of patients with SLL/CLL who develop hypercalcemia during the course of their disease and could suggest an autocrine-like mechanism involving PTHrP in Richter transformation.
2D Quasi-Static Accurate Solutions for Isotropic Thermoelastic Materials with Applications
Authors: Xiao Wen-Ying , Tong Jie , Liu Ying-Jie , Su Jiang , Li Jian-Ping
Published: April 2021

Thermally induced stress is an important scientific problem in engineering applications. In this paper, an accurate and efficient method for the two-dimensional quasi-static thermal elastic problem is established to explore the thermal stress problem. First, the compact quasi-static two-dimensional general solution is derived in terms of simple potential functions. The general solution is simple in form and can be derived for arbitrary boundary problems subjected to a line heat load. This is completely new to the literature. Second, Green’s function solutions of an infinite plane under the line pulse heat source based on the general solutions are presented to analyze the thermal stress field. Lastly, numerical results are taken into account to study the temperature and stress field induced by the dynamic heat source load. The corresponding analysis can constitute to reveal the mechanism of thermal elastic problems and provide some guidance for experiments or engineering structural design in the future work.
Safety and Efficacy of Anticoagulation in Patients with Cirrhosis: A Meta-Analysis
Authors: Chen Huan , Lei Jiaming , Liang Sicheng , Luo Gang , Deng Mingming , Lü Muhan
Published: April 2021

Background and Aims. Portal vein thrombosis is a serious adverse event that occurs during liver cirrhosis. We performed a meta-analysis to evaluate the safety and efficacy of anticoagulant therapy and prophylactic anticoagulant therapy in cirrhosis patients with (/without) portal vein thrombosis. Methods. Eligible comparative studies were identified by searching the following electronic databases: PubMed, Embase, Cochrane Library, Web of Science, and CNKI. A meta-analysis was performed to calculate odds ratios and 95% confidence intervals using fixed-effects models. Recanalization and thrombus progression were defined as the primary outcomes. Secondary outcomes included adverse events and death mortality. Results. A total of 3479 patients were included in this analysis. Compared with the control group, the recanalization rate in the anticoagulant therapy group was increased

P
<
0.00001

in patients with cirrhosis and portal vein thrombosis without increasing adverse events. Multiple use of enoxaparin in small doses is safer than single large doses

P
=
0.004

. Direct oral anticoagulants are more effective

P
<
0.00001

and safer than traditional anticoagulants. Prophylactic anticoagulant therapy can effectively prevent portal vein thrombosis formation

P

<

0.00001

. Conclusions. Anticoagulation therapy can treat or prevent portal vein thrombosis in patients with liver cirrhosis and is a relatively safe treatment.
Magnetic Resonance Imaging Classifications of Rotator Cuff Tear Are Associated with Different Shoulder Outcome Scores
Authors: Hu Xingzhen , Wang Xiaoxing , Mao Weisi , Ying Lingling , Huang Zongzhang
Published: April 2021

Objective. Rotator cuff tear (RCT) accounts for 50% of shoulder injuries, leading to chronic pain and disability in the upper extremity. The study is conducted to investigate the association between resonance imaging (MRI) classifications of patients with RCT and different shoulder outcome scores. Methods. From September 2018 to October 2019, 112 patients underwent shoulder MRI at our institution and selected as eligible study subjects according to inclusion and exclusion criteria. Among these 112 patients, 69 cases had confirmed history of shoulder trauma and 43 cases were due to chronic shoulder joint pain. The shoulder function of patients was evaluated by University of California Los Angeles Shoulder (UCLA) score, Constant-Murley score, Shoulder Pain and Disability Index (SPADI), and simple shoulder test (SST). Results. Among the 112 patients, there were 34 cases, 58 cases, and 20 cases with MRI classifications at grades I, II, and III, respectively. There was no significant difference in the injured tendons in patients with different MRI classifications (

P
>
0.05

). The injury at the supraspinatus was more common. The scores of UCLA, Constant-Murley, and SST in patients with MRI grading at grade I were significantly higher than those at grades II and III (

P
<
0.05

), which were significantly higher in patients at grade II than those at grade III (

P
<
0.05

). SPADI score in patients with MRI grading at grade I was significantly lower than that at grades II and III (

P
<
0.05

), while there was no significant difference in SPADI score between patients at grades II and III (

P
>
0.05

). MRI classifications were negatively correlated with scores of UCLA, Constant-Murley, and SST (

P
>
0.05

). There was no significant correlation between MRI grade and SPADI scores (

P
>
0.05

). Conclusion. The supraspinatus tendon injury is more common in patients with RCT. MRI classifications were negatively correlated with scores of UCLA, Constant-Murley, and SST.
Solid Organ Transplantation and Survival among Individuals with a History of Cancer
Authors: Engels Eric A. , Haber Gregory , Hart Allyson , Lynch Charles F. , Li Jie , Pawlish Karen S. , Qiao Baozhen , Yu Kelly J. , Pfeiffer Ruth M.
Published: April 2021

Background:

The success of immunotherapy highlights a possible role for immunity in controlling cancer during remission for patients with cancer in the general population. A prior cancer diagnosis is common among solid organ transplant candidates, and immunosuppressive medications administered to transplant recipients may increase recurrence risk.

Methods:

Using linked data from the United States solid organ transplant registry and 13 cancer registries, we compared overall and cancer-specific survival among patients with cancer who did versus did not receive subsequent transplantation. We used Cox regression in cohort and matched analyses, controlling for demographic factors, cancer stage, and time since cancer diagnosis.

Results:

The study included 10,524,326 patients with cancer, with 17 cancer types; 5,425 (0.05%) subsequently underwent solid organ transplantation. The median time from cancer diagnosis to transplantation was 5.7 years. Transplantation was associated with reduced overall survival for most cancers, especially cervical, testicular, and thyroid cancers [adjusted hazard ratios (aHR) for overall mortality, 3.43–4.88]. In contrast, transplantation was not associated with decreased cancer-specific survival for any cancer site, and we observed inverse associations for patients with breast cancer (aHRs for cancer-specific mortality, 0.65–0.67), non-Hodgkin lymphoma (0.50–0.51), and myeloma (0.39–0.42).

Conclusions:

Among U.S. patients with cancer, subsequent organ transplantation was associated with reduced overall survival, likely due to end-stage organ disease and transplant-related complications. However, we did not observe adverse associations with cancer-specific survival, partly reflecting careful candidate selection.

Impact:

These results do not demonstrate a detrimental effect of immunosuppression on cancer-specific survival and support current management strategies for transplant candidates with previous cancer diagnoses.
A Low Tumor Mutational Burden and PTEN Mutations Are Predictors of a Negative Response to PD-1 Blockade in MSI-H/dMMR Gastrointestinal Tumors
Authors: Chida Keigo , Kawazoe Akihito , Kawazu Masahito , Suzuki Toshihiro , Nakamura Yoshiaki , Nakatsura Tetsuya , Kuwata Takeshi , Ueno Toshihide , Kuboki Yasutoshi , Kotani Daisuke , Kojima Takashi , Taniguchi Hiroya , Mano Hiroyuki , Ikeda Masafumi , Shitara Kohei , Endo Itaru , Yoshino Takayuki
Published: April 2021

Purpose:

This study performed a comprehensive molecular characterization of microsatellite instability–high (MSI-H)/mismatch repair–deficient (dMMR) gastrointestinal (GI) tumors to elucidate predictors of response to PD-1 blockade.

Experimental Design:

Forty-five patients with MSI-H/dMMR GI tumors, including gastric cancer, colorectal cancer, cholangiocarcinoma, small intestine cancer, pancreatic cancer, and duodenal cancer, receiving PD-1 blockade were analyzed. We conducted the genomic profiling of GI tumors by whole-exome sequencing or targeted next-generation sequencing. The tumor microenvironment was evaluated by transcriptomic analysis and multiplex fluorescence IHC.

Results:

Patients with low tumor mutational burdens (TMBs) had lower objective response rates (ORRs; 0% vs. 48.8%) and a significantly shorter progression-free survival (PFS; 2.3 vs. 15.6 months; HR, 6.20; P = 0.002) than those with high TMBs. Among common gene alterations in GI tumors, only PTEN mutations, which were mutually exclusive with a low TMB, were significantly associated with a lower ORRs than wild-type PTEN (21.4 vs. 54.8%; odds, 4.45; P = 0.045). Compared with wild-type PTEN, PTEN mutations in the phosphatase domain were associated with significantly lower ORRs (12.5 vs. 54.8%; P = 0.049), shorter PFS (2.6 vs. 15.6 months; HR, 5.04; P < 0.001), lower intratumoral CD8+ T-cell levels, higher intratumoral CD204+ macrophage levels, and PI3K/AKT/mTOR pathway enrichment, whereas PTEN mutations in the C2 domain were not.

Conclusions:

Low TMBs and PTEN mutations, especially mutations in the phosphatase domain associated with an immunosuppressive environment, were mutually exclusive and might be negative predictors of PD-1 blockade responses in patients with MSI-H/dMMR GI tumors.
Insights on critical energy efficiency approaches in internet-of-things application
Authors: S. M. Sharath , P. Manjunatha , H. R. Shwetha
Published: April 2021

Internet-of-things (IoT) is one of the proliferated technologies that result in a larger scale of connection among different computational devices. However, establishing such a connection requires a fault-tolerant routing scheme. The existing routing scheme results in communication but does not address various problems directly linked with energy consumption. Cross layer-based scheme and optimization schemes are frequently used scheme for improving the energy efficiency performance in IoT. Therefore, this paper investigates the approaches where cross-layer-based schemes are used to retain energy efficiencies among resource-constrained devices. The paper discusses the effectivity of the approaches used to optimize network performance in IoT applications. The study outcome of this paper showcase that there are various open-end issues, which is required to be addressed effectively in order to improve the performance of application associated with the IoT system.
Application of BaY2F8:Er3+,Yb3+ and Mg8Ge2O11F2:Mn4+ in improving the lighting quality of phosphor-in-glass based white light-emitting diodes with the dual-convex design
Authors: Dang Huu Phuc , That Phung Ton
Published: April 2021

Although the luminous of the remote phosphor structure tends to be better than that of the in-cup or conformal phosphor structures, the poor light quality prevents this lighting method from being widely used. It is recognized through experiments that the two-layer remote phosphorus structure should be used to improve color rendering index (CRI) and color quality ratio (CQS) for WLEDs. In the experiments, WLED structures containing green BaY2F8:Er3+,Yb3+ or red Mg8Ge2O11F2:Mn4+ phosphor on the yellow YAG:Ce3+ phosphor were performed at 8500 K.. After that, Mg8Ge2O11F2:Mn4+ and BaY2F8:Er3+,Yb3+ concentrations in each WLED structure is adjusted until chromatic performance reached the finest quality. As a result, Mg8Ge2O11F2:Mn4+is proved to bring great benefits to the increase of CRI and CQS. Specifically, the greater the concentration of Mg8Ge2O11F2:Mn4+, the better CRI and CQS because of the additional red-light material from this phosphor. The other phosphor material, green BaY2F8:Er3+,Yb3+ phosphor, is beneficial for the expansion of luminous flux. However, if the concentration of Mg8Ge2O11F2:Mn4+ or BaY2F8:Er3+,Yb3+ is over the limit, the decrease in lumen output and chromatic quality will occur. While doing the experiment, Mie-scattering theory and the Beer’s law are great tools to verify the accuracy of results. The results of this article can serve the purpose of improving WLEDs fabrication to produce higher quality product.
One input voltage and three output voltage universal biquad filters with orthogonal tune of frequency and bandwidth
Authors: Pwint Wai May Phu , Chaichana Amornchai , Jaikla Winai , Siripongdee Surapong , Suwanjan Peerawut
Published: April 2021

This research paper contributes the one input three output voltage mode universal biquad filters with linear and electronic control of the natural frequency (w0), using two commercially available ICs, LT1228s as active device with two grounded capacitors, five resistors. The presented universal biquad filters can simultaneously provide three voltage-mode filtering functions, low-pass (LP), high-pass (HP) and band-pass (BP) without changing the circuit architecture. Furthermore, the first presented biquad filter provides low impedance at HP, BP voltage output nodes and LP, BP output voltage nodes are low impedance for the second proposed filter which is easy cascade ability with other voltage mode circuits without the employment of buffer circuits. The quality factor (Q) of both proposed filters is orthogonally adjusted from the passband voltage gain and w0. The proposed filters are simulated and experimented with commercially accessible ICs, LT1228. The simulated and experimental results demonstrate the filtering performances.
Bayesian learning scheme for sparse DOA estimation based on maximum-a-posteriori of hyperparameters
Authors: K. Raghu , Kumari N. Prameela
Published: April 2021

In this paper, the problem of direction of arrival estimation is addressed by employing Bayesian learning technique in sparse domain. This paper deals with the inference of sparse Bayesian learning (SBL) for both single measurement vector (SMV) and multiple measurement vector (MMV) and its applicability to estimate the arriving signal’s direction at the receiving antenna array; particularly considered to be a uniform linear array. We also derive the hyperparameter updating equations by maximizing the posterior of hyperparameters and exhibit the results for nonzero hyperprior scalars. The results presented in this paper, shows that the resolution and speed of the proposed algorithm is comparatively improved with almost zero failure rate and minimum mean square error of signal’s direction estimate.
Purging of silence for robust speaker identification in colossal database
Authors: Koteswara Rao P. Rama , Ravi Sunitha , Haritha Thotakura
Published: April 2021

The aim of this work is to develop an effective speaker recognition system under noisy environments for large data sets. The important phases involved in typical identification systems are feature extraction, training and testing. During the feature extraction phase, the speaker-specific information is processed based on the characteristics of the voice signal. Effective methods have been proposed for the silence removal in order to achieve accurate recognition under noisy environments in this work. Pitch and Pitch-strength parameters are extracted as distinct features from the input speech spectrum. Multi-linear principle component analysis (MPCA) is is utilized to minimize the complexity of the parameter matrix. Silence removal using zero crossing rate (ZCR) and endpoint detection algorithm (EDA) methods are applied on the source utterance during the feature extraction phase. These features are useful in later classification phase, where the identification is made on the basis of support vector machine (SVM) algorithms. Forward loking schostic (FOLOS) is the efficient large-scale SVM algorithm that has been employed for the effective classification among speakers. The evaluation findings indicate that the methods suggested increase the performance for large amounts of data in noise ecosystems.