bluuebunny/crossref_metadata_2025 huggingface dataset:
Control Strategies for a Dual AC Motor Pump System in Aircraft Hydraulic Power Packages
Authors: Trochelmann Nils , Thielecke Frank
Published: February 2022

Hydraulic power packages (HPP) integrate electric motor-driven pumps (EMP) and hydraulic equipment to supply (on demand) hydraulic power to specific functions. To achieve a high operational availability two redundant EMPs are installed per HPP. To produce maximum output power, the EMPs need to operate in parallel. In the first part of this paper a baseline pressure control strategy is developed that enables the parallel operating mode. It has to cover the performance requirements and it is crucial to avoid stability issues of today’s aircraft multi-pump hydraulic systems, induced by slightly differing pump characteristics. A central pressure controller, which calculates the total (cumulated) control effort and allocates it evenly to both EMPs, is selected as the basic controller structure. A loopshaping approach, where the requirements are mapped on target loop shapes, is applied. The control design is verified by nonlinear simulation and by experiments using representative aircraft prototype EMPs. Their slightly differing characteristics are utilized for an implicit proof of robustness. The second part of this paper makes use of the low utilization of the EMPs during most parts of the flight to achieve secondary objectives (efficiency, dynamic performance) and to improve the handling of operational constraints (e.g. electric input power limit). A model predictive control allocation (MPCA) algorithm flexibly allocates the total control effort to the EMP units. The allocation is derived from the solution of an optimization problem with the operational limits as constraints. Non-linear simulations of two exemplary scenarios show that the MPCA algorithm minimizes power losses by increasing the utilization of the more efficient unit. In addition, the MPCA algorithm improves the dynamic performance in case of an assymetric performance degradation by prioritizing the unit with better performance capability. The potential for improvement increases with the difference between the units and therefore offers advantages in dynamic allocation in particular for fault-tolerant operation.
Improving the Energy Efficiency of Single Actuators with High Energy Consumption
Authors: Fassbender David , Minav Tatiana , Brach Christine , Huhtala Kalevi
Published: February 2022

A load sensing (LS) supply in combination with control valves is one of the most common solutions for the actuation of implements on heavy-duty mobile machines (HDMMs). A major drawback of this approach is its relatively low energy efficiency due to metering losses—especially for multi-actuator operation and load braking. Several novel, more efficient concepts have already been proposed but involve high component costs for each actuator, which is not acceptable for HDMMs with many actuators that have a medium to low energy turnover. Therefore, this work proposes a novel system design which is based on a conventional LS system—for cheap operation of a high number of low-energy-consuming actuators—but allows to avoid metering losses for single high-energy-consuming actuators by replacing their metering valves with electric-generator-hydraulic-motor (EGHM) units that work similar to pump-controlled concepts. The benefits of the novel concept are explained in detail by looking at the three main throttling functions of an actuator in a typical valve-controlled LS systems, which the novel concept avoids by applying pressure in the actuator return lines and recuperating energy electrically instead of dissipating it by throttling. Furthermore, advantages and challenges for the novel concept are analyzed, and ways to address the latter are presented. Before the novel concept is simulated, the required control algorithms are presented. The simulation study in Amesim and Simulink focuses on a telehandler that utilizes the novel concept for the boom, extension and tilt actuators. Simulation results show that the novel system can decrease the required input energy for typical duty cycles by up to 34% compared to a conventional LS system. At the same time, simulations show that, from an economic perspective, it seems most reasonable to utilize the novel EGHM units only for the boom and extension actuators of the studied telehandler.
Load weight estimation on an excavator in static and dynamic motions
Authors: Ferlibas Mehmet , Ghabcheloo Reza
Published: February 2022

Excavators are one of the commonly used types of hydraulic machines in earth moving operations. The material handled is often transferred by dump trucks having a payload capacity that should not be exceeded. Payload monitoring systems are needed in order to prevent the possible problems during the delivery, increase the work efficiency, reduce the cost, and obtain the product information automatically without the requirement of truck scales. In this study, we propose a novel approach to estimate the load weight in the bucket of the excavator when the machine links are in motion. We consider the excavator as a three-revolute joint manipulator in vertical plane with the boom, the stick, and the bucket links. We rewrite the dynamic torque equations in a decoupled form as the linear combination of dynamic parameters and functions of joint angles, velocities, and accelerations. We perform least squares estimation to identify these parameters allowing us to predict the no load joint torques for any configuration of the links. We show that the most accurate torque prediction is the difference between the boom torque and the stick torque. We then derive the relation between the joint torques with and without the load, which are functions of the dynamic parameters. Using these equations, we can estimate the load weight. The relation becomes simpler when the links are stationary, since only the gravitational parameters remain present in the torque equations. The relation in dynamic case requires the parameters of the polar coordinates for the center of gravity of the bucket and we show that these parameters can be estimated with the knowledge of the empty bucket mass. We summarize our findings on load weight estimation for different cases including stationary poses and dynamic trajectories on free space and discuss the results. Although the friction is neglected throughout the modeling, the results obtained indicate that the effect of the static friction plays an important role in the accuracy of the estimated payload mass. We show that our dynamic model based solution is very promising, and exhibit only 2% error for high enough velocities.
The Evolution of Orbital Implants and Current Breakthroughs in Material Design, Selection, Characterization, and Clinical Use
Authors: Chen Xiao-Yi , Yang Xue , Fan Xing-Li
Published: February 2022

It is occasionally essential to surgically remove the damaged eye of the patient in the case of serious oculoorbital injuries, intraocular cancers, and other life-threatening diseases. An orbital implant is placed into the anophthalmic socket after the eye is removed to provide adequate volume reinstatement and revamp the cosmetic look of a normal eye. In the previous few decades, implant design and material selection criteria have progressed from basic nonporous polymeric spheres to devices with more complicated shapes and functions to ensure improved long-term clinical results. Because of their highly interconnected porous design, ceramic and polymeric porous implants have found popularity as a passive framework for fibrovascular ingrowth, with lower obstacle rates and the option of setting to improve prosthetic eye mobility. These materials, however, are not without flaws. The danger of migration and extrusion, infections after surgery, and poor motility transferred to the cosmetic ocular prosthesis are important elements of orbital implants of today. As a result, the development of novel biomaterials with improved functionalities (i.e., antibacterial effect, angiogenesis, and in situ moldability) that allow better eye replacement is more desirable than ever, highlighting one of the most challenging aspects of research topics in the field of ocular implants. This study highlights the history of orbital implants. It gives an outline of current advancements in the area, over and above some essential observations for materials design, selection, characterization, and transformation to clinical applications.
Shape Memory Polymer Foams With Phenolic Acid-Based Antioxidant and Antimicrobial Properties for Traumatic Wound Healing
Authors: Du Changling , Liu Jingyi , Fikhman David Anthony , Dong Katheryn Shi , Monroe Mary Beth Browning
Published: February 2022

The leading cause of trauma-related death before arrival at a hospital is uncontrolled blood loss. Upon arrival at the hospital, microbial infections in traumatic wounds become an additional factor that increases mortality. The development of hemostatic materials with antimicrobial and antioxidant properties could improve morbidity and mortality in these wounds. To that end, phenolic acids (PAs) were successfully incorporated into the network of shape memory polymer (SMP) polyurethane foams by reacting them with isocyanates. Resulting PA-containing SMP foam shape memory properties, antimicrobial and antioxidant activity, and blood and cell interactions were characterized. Results showed that p-coumaric, vanillic, and ferulic acids were successfully incorporated into the SMP foams. The PA-containing SMP foams retained the antimicrobial and antioxidant properties of the incorporated PAs, with ∼20% H2O2 scavenging and excellent antimicrobial properties again E. coli (∼5X reduction in CFUs vs. control foams), S. aureus (∼4.5X reduction in CFUs vs. control foams, with comparable CFU counts to clinical control), and S. epidermidis (∼25–120X reduction in CFUs vs. control foams, with comparable CFU counts to clinical control). Additionally, appropriate thermal and shape memory properties of PA foams could enable stable storage in low-profile secondary geometries at temperatures up to ∼55°C and rapid expand within ∼2 min after exposure to water in body temperature blood. PA foams had high cytocompatibility (>80%), non-hemolytic properties, and platelet attachment and activation, with improved cytocompatibility and hemocompatibility in comparison with clinical, silver-based controls. The incorporation of PAs provides a natural non-antibiotic approach to antimicrobial SMP foams with antioxidant properties. This system could improve outcomes in traumatic wounds to potentially reduce bleeding-related deaths and subsequent infections.
Effects of Mechanical Stress Stimulation on Function and Expression Mechanism of Osteoblasts
Authors: Liu Pan , Tu Ji , Wang Wenzhao , Li Zheng , Li Yao , Yu Xiaoping , Zhang Zhengdong
Published: February 2022

Osteoclasts and osteoblasts play a major role in bone tissue homeostasis. The homeostasis and integrity of bone tissue are maintained by ensuring a balance between osteoclastic and osteogenic activities. The remodeling of bone tissue is a continuous ongoing process. Osteoclasts mainly play a role in bone resorption, whereas osteoblasts are mainly involved in bone remodeling processes, such as bone cell formation, mineralization, and secretion. These cell types balance and restrict each other to maintain bone tissue metabolism. Bone tissue is very sensitive to mechanical stress stimulation. Unloading and loading of mechanical stress are closely related to the differentiation and formation of osteoclasts and bone resorption function as well as the differentiation and formation of osteoblasts and bone formation function. Consequently, mechanical stress exerts an important influence on the bone microenvironment and bone metabolism. This review focuses on the effects of different forms of mechanical stress stimulation (including gravity, continuously compressive pressure, tensile strain, and fluid shear stress) on osteoclast and osteoblast function and expression mechanism. This article highlights the involvement of osteoclasts and osteoblasts in activating different mechanical transduction pathways and reports changings in their differentiation, formation, and functional mechanism induced by the application of different types of mechanical stress to bone tissue. This review could provide new ideas for further microscopic studies of bone health, disease, and tissue damage reconstruction.
Turning in Circles: Understanding Manual Wheelchair Use Towards Developing User-Friendly Steering Systems
Authors: Togni Reto , Kilchenmann Andrea , Proffe Alba , Mullarkey Joel , Demkó László , Taylor William R. , Zemp Roland
Published: February 2022

For people with physical disabilities, manual wheelchairs are essential enablers of mobility, participation in society, and a healthy lifestyle. Their most general design offers great flexibility and direct feedback, but has been described to be inefficient and demands good coordination of the upper extremities while critically influencing users’ actions. Multiple research groups have used Inertial Measurement Units (IMUs) to quantify physical activities in wheelchairs arguing that knowledge over behavioural patterns in manual wheelchair usage can guide technological development and improved designs. The present study investigates turning behaviour among fulltime wheelchair users, laying the foundation of the development of novel steering systems that allow directing kinetic energy by means other than braking. Three wearable sensors were installed on the wheelchairs of 14 individuals for tracking movement over an entire week. During detected “moving windows”, phases where the velocities of the two rear wheels differed by more than 0.05 m/s were considered as turns. Kinematic characteristics for both turns-on-the-spot as well as for moving turns were then derived from the previously reconstructed wheeled path. For the grand total of 334 km of recorded wheelchair movement, a turn was detected every 3.6 m, which equates to about 900 turns per day on average and shows that changing and adjusting direction is fundamental in wheelchair practice. For moving turns, a median turning radius of 1.09 m and a median turning angle of 39° were found. With a median of 89°, typical turning angles were considerably larger for turns-on-the-spot, which accounted for roughly a quarter of the recognised turns and often started from a standstill. These results suggest that a frequent pattern in daily wheelchair usage is to initiate movement with an orienting turn-on-the-spot, and cover distances with short, straightforward sections while adjusting direction in small and tight moving turns. As large bends often require simultaneous pushing and breaking, this is, perhaps, the result of users intuitively optimising energy efficiency, but more research is needed to understand how the design of the assistive devices implicitly directs users’ movement.
Mitochondrial Inorganic Polyphosphate (polyP) Is a Potent Regulator of Mammalian Bioenergetics in SH-SY5Y Cells: A Proteomics and Metabolomics Study
Authors: Guitart-Mampel Mariona , Urquiza Pedro , Carnevale Neto Fausto , Anderson James R. , Hambardikar Vedangi , Scoma Ernest R. , Merrihew Gennifer E. , Wang Lu , MacCoss Michael J. , Raftery Daniel , Peffers Mandy J. , Solesio Maria E.
Published: February 2022

Inorganic polyphosphate (polyP) is an ancient, ubiquitous, and well-conserved polymer which is present in all the studied organisms. It is formed by individual subunits of orthophosphate which are linked by structurally similar bonds and isoenergetic to those found in ATP. While the metabolism and the physiological roles of polyP have already been described in some organisms, including bacteria and yeast, the exact role of this polymer in mammalian physiology still remains poorly understood. In these organisms, polyP shows a co-localization with mitochondria, and its role as a key regulator of the stress responses, including the maintenance of appropriate bioenergetics, has already been demonstrated by our group and others. Here, using Wild-type (Wt) and MitoPPX (cells enzymatically depleted of mitochondrial polyP) SH-SY5Y cells, we have conducted a comprehensive study of the status of cellular physiology, using proteomics and metabolomics approaches. Our results suggest a clear dysregulation of mitochondrial physiology, especially of bioenergetics, in MitoPPX cells when compared with Wt cells. Moreover, the effects induced by the enzymatic depletion of polyP are similar to those present in the mitochondrial dysfunction that is observed in neurodegenerative disorders and in neuronal aging. Based on our findings, the metabolism of mitochondrial polyP could be a valid and innovative pharmacological target in these conditions.
The Applications of Metabolic Glycoengineering
Authors: Ying Liwei , Xu Junxi , Han Dawei , Zhang Qingguo , Hong Zhenghua
Published: February 2022

Mammalian cell membranes are decorated by the glycocalyx, which offer versatile means of generating biochemical signals. By manipulating the set of glycans displayed on cell surface, it is vital for gaining insight into the cellular behavior modulation and medical and biotechnological adhibition. Although genetic engineering is proven to be an effective approach for cell surface modification, the technique is only suitable for natural and genetically encoded molecules. To circumvent these limitations, non-genetic approaches are developed for modifying cell surfaces with unnatural but functional groups. Here, we review latest development of metabolic glycoengineering (MGE), which enriches the chemical functions of the cell surface and is becoming an intriguing new tool for regenerative medicine and tissue engineering. Particular emphasis of this review is placed on discussing current applications and perspectives of MGE.
Yeast Vps13 is Crucial for Peroxisome Expansion in Cells With Reduced Peroxisome-ER Contact Sites
Authors: Yuan Wei , Akşit Arman , de Boer Rinse , Krikken Arjen M. , van der Klei Ida J.
Published: February 2022

In the yeast Hansenula polymorpha the peroxisomal membrane protein Pex11 and three endoplasmic reticulum localized proteins of the Pex23 family (Pex23, Pex24 and Pex32) are involved in the formation of peroxisome-ER contact sites. Previous studies suggested that these contacts are involved in non-vesicular lipid transfer and important for expansion of the peroxisomal membrane. The absence of Pex32 results in a severe peroxisomal phenotype, while cells lacking Pex11, Pex23 or Pex24 show milder defects and still are capable to form peroxisomes and grow on methanol. We performed transposon mutagenesis on H. polymorpha pex11 cells and selected mutants that lost the capacity to grow on methanol and are severely blocked in peroxisome formation. This strategy resulted in the identification of Vps13, a highly conserved contact site protein involved in bulk lipid transfer. Our data show that peroxisome formation and function is normal in cells of a vps13 single deletion strain. However, Vps13 is essential for peroxisome biogenesis in pex11. Notably, Vps13 is also required for peroxisome formation in pex23 and pex24 cells. These data suggest that Vps13 is crucial for peroxisome formation in cells with reduced peroxisome-endoplasmic reticulum contact sites and plays a redundant function in lipid transfer from the ER to peroxisomes.
Heart in a Dish: From Traditional 2D Differentiation Protocols to Cardiac Organoids
Authors: Ramirez-Calderon Gustavo , Colombo Giovanni , Hernandez-Bautista Carlos A. , Astro Veronica , Adamo Antonio
Published: February 2022

Human pluripotent stem cells (hPSCs) constitute a valuable model to study the complexity of early human cardiac development and investigate the molecular mechanisms involved in heart diseases. The differentiation of hPSCs into cardiac lineages in vitro can be achieved by traditional two-dimensional (2D) monolayer approaches or by adopting innovative three-dimensional (3D) cardiac organoid protocols. Human cardiac organoids (hCOs) are complex multicellular aggregates that faithfully recapitulate the cardiac tissue’s transcriptional, functional, and morphological features. In recent years, significant advances in the field have dramatically improved the robustness and efficiency of hCOs derivation and have promoted the application of hCOs for drug screening and heart disease modeling. This review surveys the current differentiation protocols, focusing on the most advanced 3D methods for deriving hCOs from hPSCs. Furthermore, we describe the potential applications of hCOs in the pharmaceutical and tissue bioengineering fields, including their usage to investigate the consequences of Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS-CoV2) infection in the heart.
Antagonistic Coevolution Limits the Range of Host Defense in C. elegans Populations
Authors: Lewis Jordan A. , Penley McKenna J. , Sylla Hannan , Ahumada Sebastián Durán , Morran Levi T.
Published: February 2022

Host populations often evolve defenses against parasites due to the significant fitness costs imposed by infection. However, adaptation to a specific parasite may alter the effectiveness of the host’s defenses in general. Consequently, the specificity of host defense may be influenced by a host population’s evolutionary history with parasites. Further, the degree of reciprocal change within an interaction may profoundly alter the range of host defense, given that antagonistic coevolutionary interactions are predicted to favor defense against specific parasite genotypes. Here, we examined the effect of host evolutionary history on host defense range by assessing the mortality rates of Caenorhabditis elegans host populations exposed to an array of Serratia marcescens bacterial parasite strains. Importantly, each of the host populations were derived from the same genetic background but have different experimental evolution histories with parasites. Each of these histories (exposure to either heat-killed, fixed genotype, or coevolving parasites) carries a different level of evolutionary reciprocity. Overall, we observed an effect of host evolutionary history in that previously coevolved host populations were generally the most susceptible to novel parasite strains. This data demonstrates that host evolutionary history can have a significant impact on host defense, and that host-parasite coevolution can increase host susceptibility to novel parasites.
Age-Associated Changes of Nasal Bacterial Microbiome in Patients With Chronic Rhinosinusitis
Authors: Chen Fang , Gao Wenxiang , Yu Chaosheng , Li Junzheng , Yu Feng , Xia Meng , Liang Jiajian , Shi Jianbo , Lai Yinyan
Published: February 2022

Age-related changes in nasal bacterial microbiota of patients with chronic rhinosinusitis (CRS) remains unclear. In this study, we aimed to identify distinct characteristics of nasal bacterial microbiota between aged and younger patients with CRS through 16S rDNA gene sequencing. Patients with CRS undergoing endoscopic sinus surgery were recruited and separated into aged (≥60 years, median age = 66 years, N = 17) and younger (<60 years, median age = 35.5 years, N = 14) patients. Diversity, bacterial composition and metabolic activities of nasal microbiota between aged and younger patients were compared. Results have shown that levels of OTUs (p = 0.0173) and microbiota diversity (all p < 0.05) decreased significantly in aged patients. The abundance of phylum Actinobacteria, and genus Corynebacterium were significantly higher in aged patients, while the abundance of phylum Bacteroidetes, Fusobacteria, and genus Fusobacterium, Peptoniphilus were significantly higher in younger patients. In addition, predicted functional profiles have revealed that 41 KEGG pathways involving in 12 metabolic pathways, 4 genetic information processing, 3 environmental information processing, 4 cellular processes, 8 organismal systems, 6 human diseases, and 4 unclassified pathways were identified. Among which, the vast majority of metabolic activities are involved in replication and repair, membrane transport, translation, and the metabolism of amino acid, carbohydrate, energy, cofactors and vitamins, and nucleotide. On the level of the thirdly bacterial metabolic pathways, purine metabolism, glycine, serine and threonine metabolism, valine, leucine and isoleucine biosynthesis, glycolysis/gluconeogenesis and phenylalanine, tyrosine and tryptophan biosynthesis are significantly up-regulated while carbon fixation pathways in prokaryotesand methane metabolism are significantly down-regulated in aged patients. Overall, our analysis revealed that age-related physiological and pathological changes on the nasal mucosal surface may alter the host immune response and be highly associated with the nasal bacterial microbiota of patients with CRS. However, future studies are needed to elucidate the causal relationship.
Midwall Fibrosis and Cardiac Mechanics: Rigid Body Rotation Is a Novel Marker of Disease Severity in Pediatric Primary Dilated Cardiomyopathy
Authors: Al-Wakeel-Marquard Nadya , Seidel Franziska , Kühnisch Jirko , Kuehne Titus , Berger Felix , Messroghli Daniel R. , Klaassen Sabine
Published: February 2022

Background

Midwall fibrosis (MWF) detected by late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) predicts adverse outcome in adults with dilated cardiomyopathy (DCM). Its relevance in children and adolescents is relatively unknown. Left ventricular (LV) strain, rotation and twist are important parameters of cardiac function; yet, their role in pediatric heart failure is understudied. This study aimed to evaluate MWF and cardiac mechanics in pediatric DCM.

Methods

Patients ≤21 years with primary DCM were prospectively enrolled and underwent standardized CMR including LGE. All participants were categorized according to the presence or absence of MWF (MWF+ vs. MWF–). Cardiac mechanics were assessed using CMR feature tracking. Impaired LV twist with apex and base rotating in the same direction was termed rigid body rotation (RBR).

Results

In total, 17 patients (median age 11.2 years) were included. MWF was present in seven patients (41%). Median N-terminal pro brain natriuretic peptide (NT-proBNP) was higher (5,959 vs. 242 pg/ml, p = 0.887) and LV ejection fraction (LVEF) lower (28 vs. 39%, p = 0.536) in MWF+ vs. MWF– patients, yet differences were not statistically significant. MWF+ patients had reduced global longitudinal (GLS), circumferential (GCS) and radial strain (GRS), again without statistical significance (p = 0.713, 0.492 and 1.000, respectively). A relationship between MWF and adverse outcome was not seen (p = 0.637). RBR was more common in MWF+ (67 vs. 50%), and was associated with the occurrence of adverse events (p = 0.041). Patients with RBR more frequently were in higher New York Heart Association classes (p = 0.035), had elevated NT-proBNP levels (p = 0.002) and higher need for catecholamines (p = 0.001). RBR was related to reduced GLS (p = 0.008), GCS (p = 0.031), GRS (p = 0.012), LV twist (p = 0.008), peak apical rotation (p < 0.001), and LVEF (p = 0.001), elevated LV end-diastolic volume (p = 0.023) and LV end-systolic volume (p = 0.003), and lower right ventricular stroke volume (p = 0.023).

Conclusions

MWF was common, but failed to predict heart failure. RBR was associated with clinical and biventricular functional signs of heart failure as well as the occurrence of adverse events. Our findings suggest that RBR may predict outcomes and may serve as a novel marker of disease severity in pediatric DCM.

Clinical Trial Registration:https://clinicaltrials.gov/, identifier: NCT03572569.
A Concomitant Cancer Diagnosis Is Associated With Poor Cardiovascular Outcomes Among Acute Myocardial Infarction Patients
Authors: Peng Xiang , Wang Zhuozhong , Cao Muhua , Zheng Yuqi , Tian Ya'nan , Yu Li , Ni Wenjun , Wang Shanjie , Qin Zhifeng , Zhao Suhong , Tian Jinwei , Yu Bo
Published: February 2022

Background and Aims

With the increasing coexistence of cardiovascular disease and cancer in contemporary clinical practice, studies on the outcomes in acute myocardial infarction (AMI) patients with cancer has not been systematically investigated. This study sought to investigated the effect of coexisting cancer on the treatment and clinical outcomes among AMI patients.

Methods

We retrospectively integrated and analyzed cardiovascular data of 6,607 AMI patients between June 2016 and December 2019. Patients with cancer were compared with pair-matched cancer-naive patients. Cox proportional hazards models were constructed to compare the differences in outcomes.

Results

Of 6,607 patients, 2.3% (n = 150) had been diagnosed with cancer. Patients with cancer were older (70.3 ± 10.0 vs. 63.9 ± 11.5 years, P < 0.001) and had a higher burden of comorbidities. Moreover, patients with cancer tended to receive clopidogrel (52.0 vs. 40.0%, P = 0.004) rather than ticagrelor (45.6 vs. 58.2%, P = 0.003) than those without cancer. After pairwise matching, patients with cancer were less likely to undergo in-hospital percutaneous coronary intervention (61.3 vs. 70.0%, P = 0.055). And after 3-year follow-up, the cumulative incidence of cardiovascular death (14.0 vs. 8.3%; adjusted HR, 1.93; 95% CI, 1.11–3.39; P = 0.021) among patients with cancer was significantly higher than that among the matched controls, a similar pattern was observed for the composite outcome of cardiovascular death, non-fatal myocardial infarction, and non-fatal stroke (16.0 vs. 10.3%; adjusted HR, 1.98; 95% CI, 1.21–3.26; P = 0.007). Moreover, patients with a historical cancer diagnosis within 5 years had a higher risk of cardiovascular ischemic events.

Conclusions

AMI patients with a concomitant diagnosis of cancer tended to be treated with conservative therapies and were at substantially higher risk for adverse cardiovascular outcomes.
Risk Factors for the Comorbidity of Hypertension and Renal Cell Carcinoma in the Cardio-Oncologic Era and Treatment for Tumor-Induced Hypertension
Authors: Ba Zhengqing , Xiao Ying , He Ming , Liu Dong , Wang Hao , Liang Hanyang , Yuan Jiansong
Published: February 2022

Advances in tumor diagnosis and treatment, especially the use of targeted therapies, have remarkably improved the survival rate of patients with renal cell carcinoma (RCC), accompanied by higher hypertension (HTN) incidence among patients with RCC, reflecting the coming of a cardio-oncologic era. Therefore, for patients with RCC and HTN simultaneously, finding risk factors for the comorbidity and giving better clinical treatment have been urgent problems. In this review, we thoroughly investigated risk factors for the comorbidity of HTN and RCC based on preclinical and clinical studies. Firstly, RCC and HTN may have common risk factors, such as obesity, smoking, and other modifiable lifestyles. Secondly, RCC and HTN may lead to each other directly or indirectly by their therapies. We then discussed measures of reducing the comorbidity and treatment of HTN in patients with RCC. We also discussed the deficiency of current studies and pointed out future directions. In conclusion, this review aims to deepen the understanding of cardio-oncology and bring benefit to the population who are at high risk of getting or have already got RCC and HTN simultaneously.
Value of the Systemic Immune-Inflammatory Index (SII) in Predicting the Prognosis of Patients With Peripartum Cardiomyopathy
Authors: Zhang Yuan , Liu Wenzhao , Yu Huaitao , Chen Zhen , Zhang Chunmei , Ti Yun , Bu Peili
Published: February 2022

Background

Peripartum cardiomyopathy (PPCM) is a potentially life-threatening complication of pregnancy. The identification of early prognostic markers in patients diagnosed with PPCM is very important. The systemic immune-inflammation index (SII) is a new inflammatory biomarker, and the aim of this study was to evaluate the prognostic value of SII in patients with PPCM.

Methods

A total of 61 patients with PPCM who were admitted in our hospital from 2015 to 2020 were retrospectively analyzed in this study. The follow-up period of all patients was at least 6 months after diagnosis. Recovery of left ventricular (LV) systolic function was defined as the presence of left ventricular ejection fraction > 45%. The second endpoint was defined as composite adverse cardiac events, including cardiac death or hospitalization due to worsening heart failure. Univariate and multivariate logistic regression analysis were used to determine the independent predictors of non-recovery of LV systolic function. The receiver operating characteristic (ROC) curve analysis was used to establish a cut-off level of SII value to predict persistent LV systolic dysfunction.

Results

The follow-up duration was 40.5 ± 16.3 months. Among the 61 patients, 43 patients showed left ventricular recovery and 18 patients did not at the last follow-up visit. The baseline SII levels were significantly higher in the non-recovery group (P < 0.05). Multivariate logistic regression showed that the SII and left ventricular end-diastolic dimension (LVEDD) were independent predictors of persistent LV systolic dysfunction (OR: 1.177, 95% CI: 1.038–1.335, P = 0.011 and OR: 1.148, 95% CI: 1.011–1.304, P = 0.033, respectively). A SII value of 876 was the best cut-off value (the area under the curve was 0.791, 95% CI: 0.667–0.915, P < 0.05), and the sensitivity and specificity were 73 and 71%, respectively.

Conclusions

The SII and LVEDD are independent prognostic factors for persistent LV systolic dysfunction in patients with PPCM. The SII may be a useful tool for identifying high-risk PPCM patients.
A Testing Apparatus for Gas-Driven Coal and Gas Outbursts and its Application
Authors: Zou Yunlong , Peng Bo , Liu Rong , Fan Jinyang
Published: February 2022

In this study, a multi-physics coal and gas outburst experimental apparatus is developed to allow investigating the gas-driven mechanism behind the disaster caused by coal and gas outbursts in tectonic regions. The apparatus can simulate the coal and gas outbursts under different initial geo-stresses, gas pressures and temperatures. By integrating acoustic emission sensors in the holes on axial platens, acoustic signals from coal samples during the whole test can be monitored. A series of testability experiments were conducted on the developed apparatus to verify its performance. The damage characteristics and outburst occurrence of raw coal under different gas pressures were experimentally studied and that provided a more complete theoretical basis for coal and gas outburst. The degree of fragmentation of coal samples and the mass proportion distributions of the outburst pulverized coal after outbursts under different gas pressures were analyzed, as a reference for exploring the evolutionary characteristics of coal and gas outburst with gas-driven action.
Biological Nitrogen Fixation and Nitrogen Accumulation in Peatlands
Authors: Yin Tianya , Feng Maoyuan , Qiu Chunjing , Peng Shushi
Published: February 2022

Peatlands cover about 3% of the Earth’s surface and are regarded as a vital carbon (C) pool and sink. The formation of peatland is supported by continuously supplied nitrogen (N) but the sources of this N remain unclear. Here, we first review N stocks and the rate they accumulate in peatlands, then we present the sources of N, especially through biological nitrogen fixation (BNF). We found that global peatlands store 5.9–25.9 Gt N. In the past millennia, northern peatlands have a lower N accumulated rate than tropical undisturbed peatlands. BNF rate is approximately 1.9 ± 2.7 g m−2 yr−1 in northern peatlands, higher than the rate of N deposition, 0.5 ± 0.4 g m−2 yr−1. For tropical peatlands, BNF observation has hardly been reported yet and needs further investigation. This review provides a broad picture of peatland N cycling and suggests that there are large uncertainties, due to limited observations of BNF and N fluxes by inflow and outflow runoff. Therefore, we call for more efforts contributing to field observations and modelling of the N budget in peatlands.
Spatial Distribution of Unique Biological Communities and Their Control Over Surface Reflectivity of the Stanley Glacier, Uganda
Authors: Uetake Jun , Samyn Denis , Anguma Simon , Takeuchi Nozomu
Published: February 2022

Diverse microbes have been revealed to live in glaciers worldwide, but only a few biological studies were dedicated to glaciers in tropical Africa. These glaciers are shrinking rapidly and are expected to disappear shortly. In this study, we carried out biological and glaciological field observations on Stanley Glacier, the largest remaining glacier in the Rwenzori Mountains, Uganda, Africa. Microbial aggregates ranging from micrometer to centimeter in size were found on the glacier surface and contained moss and various types of Chlorophyta, among which a new endemic species of green alga. Concentrations of total impurities on the glacier surface, including microbial aggregates, varied spatially and decreased as altitude increased. The large microbial aggregates (larger than 4 cm in diameter) were found only at the glacier surface near the terminus and side margins, where the surface was less frequently covered with snow. It is also shown that the total organic matter on the glacier surface is determined by the timing of snow cover, which affects the quantity of solar radiation reaching the glacier ice surface. Furthermore, the total impurity content was negatively correlated with surface reflectivity, revealing their potential role in albedo reduction at the glacier surface through positive feedback between enhanced meltwater and increased biological growth.
Tectonic and Climatic Control on Quaternary Exhumation in the Eastern Pamir Domes, Western China: Insights From Geomorphic Approaches
Authors: Cao Kai , Mai Hongtao , Chevalier Marie-Luce , Wang Guocan
Published: February 2022

The Kongur Shan and Muztaghata massifs, bounded by the Kongur Shan extensional system (KES), represent tectonic and topographic anomalies in the eastern Pamir region. They are ideal examples to study how normal faulting and surface erosion influence Quaternary exhumation of the dome system. We apply multiple geomorphic parameters, including hypsometric integral, stream length-gradient index, drainage basin shape, drainage basin asymmetry and ratio of valley floor width to valley height, for the catchments on both sides of the range. We first evaluated the validity of various indices and chose three active tectonic-sensitive indices to establish a newly-integrated parameter (Iat) that is used to measure relative intensities of tectonic activity in active orogens. Results suggest stronger tectonic activity west of the domes along the Kongur Shan normal fault (KSF) and Muji dextral strike-slip fault, compared to the eastern side, along the Ghez and Kalagile faults. This first-order observation reflects tectonic control on the topographic development of the domal structure, consistent with eastward crustal tilting, attested by older thermochronology ages to the east. On the western flank of the range, stronger tectonic activity occurs mostly on the Muji fault, Kingata Tagh - Kongur Shan fault segment, as well as along the western and southern Muztaghata segments of the Kongur Shan fault. This is consistent with field investigations of Quaternary offsets of landforms, which suggest continuous activity of the Muji fault and KSF since the late Miocene. Average basin-wide erosion rates derived from stream power models are highest near the Kongur Shan dome, and gradually decrease southwards and northwards, in agreement with the spatial pattern of long-term exhumation rates in the footwall of the KSF obtained by low-temperature thermochronology data. Positive correlation between exhumation/erosion rates and extensional rates along the active faults located west of the domes indicates that extensional deformation likely plays a dominant role in controlling focused dome exhumation/erosion. However, considering peaked exhumation/erosion rates, stronger rock resistivity and steeper glacial landforms, attest to the important role of glacial buzz-saw in reshaping the recent dome’s landscape.
pH-Responsive Drilling Fluid With High-Temperature and High-Density Performance
Authors: Li Daqi , Jin Junbin , Zhang Dujie , Li Fan , Wang Xianguang , Liu Lu
Published: February 2022

Conventional drilling fluids experience the problems of a low cleanup efficiency and oily drilled cutting disposal. To resolve these problems, a type of pH-responsive drilling fluid with a temperature resistance of up to 150°C resistance a density of 1.5 g/cm3 was prepared using mixed emulsifiers. Stable reversion from a water-in-oil (W/O) emulsion to an oil-in-water (O/W) and vice versa was realized. The results of light backscattering and sag stability suggested that the W/O and O/W emulsion-based drilling fluids showed excellent resistance to coalescence or sedimentation. There was no demulsification or barite sedimentation during emulsion reversion. W/O and O/W emulsions exhibited small droplet sizes and uniform distributions. The properties of the W/O and O/W emulsion-based drilling fluids were similar even after hot rolling at 150°C for 16 h. The reversible drilling fluid showed excellent resistance to contamination by saline water and drilled cuttings. The residual W/O emulsion-based drilling fluid was cleaned with acids at a high efficiency. The oil content of the drill cuttings generated by the W/O emulsion-based drilling fluid was reduced using simple acids. The improved reversion stability with high temperature and density resistance makes it possible for applicable reversible drilling fluid in deep or ultra-deep wells required by different geological formation.
Predictors of Central Student Learning Outcomes in Times of COVID-19: Students’, Parents’, and Teachers’ Perspectives During School Closure in 2020—A Multiple Informant Relative Weight Analysis
Authors: Helm Christoph , Huber Stephan Gerhard
Published: February 2022

School closures associated with the COVID-19 pandemic very quickly led to many studies on distance education. Currently, there are only studies available that explored the importance of different features of distance education for student learning during school lockdowns in 2020 relying on a single perspective—student, parent, or teacher data. Thus, we present results from a multiple informant study in which we compared prediction models based on the different perspectives of relevant actors in the school system. Against the background of the context, input, process, and output model, we explored the impact of a broad range of features of distance education on central student learning outcomes using data from students (N = 315), parents (N = 518), and teachers (N = 499) in German and Austrian secondary schools. Although findings from relative weight analysis portray a relatively similar pattern of relevant predictors for students’ learning outcomes (i.e., self-rated achievement, learning effort, and intrinsic motivation) across the three respondent groups, some predictors largely differ between the groups. While students’ ability to self-organize emerged as the most significant predictor across all three informant groups, predictors, such as the lack of parental support during school closure, turned out to be relevant only from parents’ perspective. We discuss the implications of these findings for future educational practice and research.
Nurturing Ubuntu, the African Form of Human Flourishing Through Inclusive Home Based Early Childhood Education
Authors: Ejuu Godfrey , Opiyo Rose Atieno
Published: February 2022

Human flourishing has recently gained more attention in the world as a prerequisite safety net for better human resilience in uncertain times. While most Western authors believe that human flourishing is an individual issue, gained in later life, African communities that are largely communal may not have the same view. Communalism as opposed to individualism as a key pillar in African Ubuntu thinking makes it a possibility that there is a departure in the contextualisation of human flourishing and its pathways. This explores the African conceptualisation of flourishing in the Ubuntu lens and how communities are coming together to cultivate it by implementing home based early childhood learning centres. Desk review was used to learn the contextual meaning of human flourishing and different pathways to it in African community settings. Home based early learning centres operated by parents was seen as a core activity to nurture Ubuntu, as each family and community member becomes useful in provide a service that helps others to flourish at different stages of life. The paper concludes that the use of the home-based early childhood model as a flourishing intervention helps to engage every member of the community for the good of their children, bringing live the Ubuntu saying “I am a person because of other persons.” This study is significant in that it proposes home-based early learning as a more viable pathway way to human flourishing and redirects the focus of flourishing to a younger age group.
Effect of Moderate Aerobic Exercise on Complement Activation Pathways in Polycystic Ovary Syndrome Women
Authors: Ramanjaneya Manjunath , Abdalhakam Ibrahem , Bettahi Ilham , Bensila Milin , Jerobin Jayakumar , Aye Myint Myint , Alkasem Meis , Sathyapalan Thozhukat , Atkin Stephen Lawrence , Abou-Samra Abdul-Badi
Published: February 2022

Background

The complement system is pivotal in host defense mechanisms, protecting against pathogenic infection by regulating inflammation and cell immunity. Complement-related protein activation occurs through three distinct pathways: classical, alternative, and lectin-dependent pathways, which are regulated by cascades of multiple proteins. Complement activation is recognized in polycystic ovary syndrome (PCOS) to be associated with obesity and insulin sensitivity. Exercise reduces insulin resistance and may help reduce obesity, and therefore, this study was undertaken to determine the effect of exercise on the activation of complement-related proteins in PCOS and control women.

Subjects and Measurements

In this study, 10 controls and 11 PCOS subjects who were age- and weight-matched underwent an 8-week supervised exercise program at 60% maximal oxygen consumption. Weight was unchanged though insulin sensitivity was increased in PCOS subjects and controls. Fasting baseline and post-exercise samples were collected and 14 complement-related proteins belonging to classical, alternative, and lectin-dependent pathways were measured.

Results

Baseline levels of complement C4b and complement C3b/iC3b were higher in PCOS (P < 0.05) compared with controls. Exercise reduced complement C1q (P < 0.05), C3 (P < 0.001), C4 (P < 0.01), factor B (P < 0.01), factor H (P < 0.01), and properdin (P < 0.05) in controls, but not in PCOS women.

Conclusion

Exercise induced complement changes in controls that were not seen in PCOS subjects, suggesting that these pathways remain dysregulated even in the presence of improved insulin sensitivity and not improved by moderate aerobic exercise.

Clinical Trial Registration

ISRCTN registry, ISRCTN42448814.