bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of layer thickness on the overhanging surface quality manufactured by selective laser melting
Authors: Duan Weipeng , Wu Meiping , Han Jitai , Ma Yiqing , Miao Xiaojin
Published: December 2021

With the increasing demand for the precision of lightweight part, overhanging surface quality has attracted more and more attentions in recent years. In this work, the relationship between overhanging surface quality and layer thickness was studied. The testing results revealed that with the increasing of the layer thickness, surface quality, especially the surface flatness, showed a significant decreasing trend due to the decreasing of the bending deformation. When layer thickness was ranged from 0.15 to 0.18, it reached a relative optimal condition while the sinking distance and flatness within 0.095 mm–0.1 mm and 0.076 mm–0.078 mm, respectively. With the further increasing of the layer thickness, both sinking distance and surface flatness had a quite significant decreasing due to the increasing gravity of the overhanging layer powder and bonded powder caused by the molten pool sinking. Combined to the experimental data and the analysis given above, the structure of the overhanging surface was optimized and the surface quality showed a further increase.
Numerical simulation method of submerged arc surfacing process of rollers
Authors: Li Chang , Huang Qingchun , Xu Yan , Han Xing
Published: December 2021

The submerged arc surfacing process involves complex behaviors such as metal heat transfer, melting, flow, phase transformation, and solidification and involves the interaction of electric field, thermal field, magnetic field, and flow field. At present, it is impossible to reveal the transient mechanism of multi-field coupling in submerged arc surfacing by experience or trial and error, which is not conducive to shorten the development cycle and save the cost. Moreover, it is difficult to measure the molten pool velocity, von Mises stress, and phase transformation zone in real-time. However, these factors are the key to obtain a high-quality surfacing layer. Therefore, a three-dimensional mathematical model of heat force flow multi-field coupling for roller submerged arc surfacing is established in this article. The distribution and variation of welding temperature, von Mises stress, molten pool flow field, and phase transformation zone are revealed by solving the model. The maximum von Mises stress of the rollers during submerged arc surfacing is 432 MPa. The depth of the phase transformation is 2.50 mm, and the width is 1.98 mm. Zeiss-IGMA HD FESEM was used to observe the welding microstructure. The results show that the main microstructure is martensite and a small amount of ferrite.
Numerical investigations on leakage performance and flow mechanism of spiral groove seal for shrouded blade in axial turbine
Authors: Xiong Jun , Zhu Yangli , Wang Xing , Chen Haisheng , Wang Junfeng
Published: December 2021

Flow field of shroud leakage flow for a single-stage axial turbine has been investigated in this article. The spiral groove seal (SGS) is adopted for shrouded rotor blade to reduce tip leakage and improve turbine aerodynamic performance. A series of three-dimensional (3D) computational fluid dynamics (CFD) simulations are performed to investigate leakage characteristics and flow mechanism of various configurations with different angle, depth, width, and grooves number of the SGS. The original staggered labyrinth seal (LS) is also calculated for comparison. The results illustrate that small spiral groove angle can create more axial flow resistance; meanwhile, it will increase grooves number existing in the axial direction. Groove depth and tooth width will influence the number, shape, and strength of vortex in the groove. The leakage mass flow can be reduced by 36% and isentropic efficiency of the turbine can be increased by 0.26% when spiral groove angle, depth, and width of the SGS are 1.5°, 1.8 mm, and 0.8 mm, respectively. Overall, the optimal SGS can influence vortex generation and enhance energy dissipation in shroud cavity to reduce the leakage and suppress mixing loss of leakage flow with the main flow to some extent. It can be attributed to the combination of throttling effect and pumping effect of the SGS that realize leakage reduction and efficiency improvement. As a result, the SGS can effectively improve tip leakage flow of shrouded blade in axial turbine.
Effect of brass interlayer on microstructure, mechanical and corrosion behaviour of friction stir welded AA6061-T6 alloy
Authors: Nagu Korra , Kumar Adepu
Published: December 2021

In this study, friction stir welding (FSW) was performed on AA6061-T6 with and without brass interlayer. The FSW with interlayer was performed for various tool rotational speeds (600–1000 r/min) and at constant travel speed (25 mm/min). The defect-free joint with uniform distribution of brass particles in the stir zone (SZ) and formation of the uniform composite structure was observed at an intermediate optimized tool rotational speed of 800 r/min due to the proper material flow. A strong metallurgical bond between brass particles with aluminium alloy resulted in the formation of Al2Cu and Al4Cu9 strengthening intermetallic compounds (IMCs). The average grain size obtained for the weld with interlayer is smaller than weld without interlayer. The presence of the interlayer enhanced the hardness and the tensile strength compared to the weld without interlayer. This improvement in mechanical properties with interlayer is attributed to the formation and uniform distribution of strengthening IMCs. The corrosion analysis was carried out in 3.5% NaCl solution using immersion test and electrochemical polarization test. The weld with interlayer showed enhanced corrosion resistance than the weld without interlayer which is attributed to the formation of major Al2Cu IMC which has less activation energy for the corrosion process.
In-depth analysis of crack area characteristics of fisheye failures influenced by the multiaxial stress condition in the tooth root fillet of high-strength gears
Authors: Fuchs Daniel , Rommel Sascha , Tobie Thomas , Stahl Karsten
Published: December 2021

Modern high-strength gears have to satisfy many requirements, such as improved tooth root bending strength. The process of shot-peening is correlated to the introduction of compressive residual stresses in the surface layer of a gear to achieve a higher tooth root bending strength. However, due to the compressive residual stresses fisheye failures can occur and can have a determining effect on the endurance of high-strength gears. By preventing such failures, it should be possible to increase further the tooth root bending strength of high-strength gears. However, this requires a deeper understanding of the crack initiation and propagation processes. Especially the unique multiaxial stress condition in the tooth root fillet of a gear could influence the crack area characteristics significantly. Though, in the literature there is no proper characterization of crack area characteristics in the tooth root fillet of gears in detail, so far. Furthermore, in previous work a model approach for the evaluation of the tooth root bending strength of gears was presented, which is based on the results of Murakami. A first comparison with experimental data showed a basic applicability of the model approach on gears. However, the derived model approach showed some room for improvement. Questions arose as to whether the approach is really fully applicable to gears, whether further modifications are needed, or whether further extension is even practical, since the fisheye fracture characteristics of gears might differ significantly from those of standard specimens. The aim of this paper is therefore to present an extensive in-depth analysis of the crack area characteristics in the event of tooth root fracture damages caused by a fisheye failure in high-strength gears. Furthermore, a case study is used to verify whether a detailed evaluation of the characteristics of non-metallic inclusions leads to more accurate results of the model approach.
Motivations and Barriers for Adult Learner Achievement: Recommendations for Institutions of Higher Education
Authors: Bellare Yamini , Smith Adam , Cochran Kelcee , Lopez Samuel Garcia
Published: December 2021

Recent trends in higher education indicate a steady increase in the number of adult and non-traditional learners returning to complete college degrees. Though higher education can provide numerous economic and career enhancement opportunities, adult learners experience several challenges when they return to college. The purpose of this qualitative research study was to gather and analyze data from employees from companies in the Midwest to determine the challenges and motivations of adult learners who plan to return to higher education. The results highlight that it is important for institutions of higher education to collaborate with employers to identify ways to modify their student recruitment methods to attract more adult student learners and identify supportive resources to help them complete their degrees successfully.
HIV and TB Workplace Program for Street Vendors: A Situational Analysis
Authors: Mlangeni Nosimilo , Du Preez Karen , Mokone Moses , Malotle Molebogeng , Kisting Sophia , Ramodike Jonathan , Zungu Muzimkhulu
Published: December 2021

In South Africa, 15 percent of informal economy workers are street vendors. The organization of occupational health services in the country is fragmented and does not cover informal workers. Conditions of work make informal workers extremely vulnerable to human immunodeficiency virus (HIV) and tuberculosis (TB) exposure. In this study, a qualitative risk assessment was conducted among street vendors, followed by focus group discussions. Interpretation of data was according to major themes extracted from discussions. Workers are exposed to several occupational health hazards identified during the risk assessment. There is a lack of workplace HIV and TB services and overall poor access to healthcare. Street vendors, especially females, are at higher risk of HIV, due to gender inequalities. Comprehensive gender-sensitive training on occupational health and safety, HIV, and TB should be prioritized. To reach Universal Health Coverage and achieve the Sustainable Developmental Goals’ targets, the health system should improve services for informal economy workers.
An Intrahepatic Cholangiocarcinoma with Focal Rhabdoid Features and SMARCA4-Deficiency
Authors: Minato Hiroshi , Yoshikawa Akane , Katayanagi Kazuyoshi , Kurumaya Hiroshi , Kato Kaichiro , Kitamura Hirotaka
Published: December 2021

Intrahepatic cholangiocarcinoma with rhabdoid morphology is rare, and only three case reports have been published to date, none of which discuss the genetic changes in the rhabdoid component. We present a case of intrahepatic cholangiocarcinoma with focal rhabdoid features and SMARCA4-deficiency detected using immunohistochemistry. A Japanese man in his 60s without viral hepatitis was diagnosed with an avascular tumor in the liver, measuring 4.4 cm in the greatest dimension. The tumor was mostly composed of moderately differentiated adenocarcinoma, focal poorly differentiated adenocarcinoma, and an undifferentiated rhabdoid component. Immunohistochemical analysis showed an inclusion-like staining pattern for keratin AE1/AE3 and vimentin in the rhabdoid component. BRG1/SMARCA4 was detected in the differentiated component but not in the poorly- and undifferentiated components. Our novel findings reflecting the morphological and genetic heterogeneity of intrahepatic cholangiocarcinoma and will aid the research on drugs targeting the aberrant SWItch/Sucrose NonFermentable complex.
Attrition of Police Officers With Immigrant Background
Authors: Fekjær Silje Bringsrud , Alecu Andreea Ioana
Published: December 2021

Recruiting police officers with immigrant backgrounds has a limited effect if many of these recruits leave the police service. The dropout and attrition rates among officers with immigrant backgrounds are also an important indicator of the challenges this group faces when joining the police profession. We investigated police education dropout patterns and attrition rates among police students and officers with immigrant backgrounds. Our study is based on detailed longitudinal data with total coverage of the population, which were previously unavailable for police career studies. Using logistic regression and coarsened exact matching, we analysed administrative registry data covering all individuals admitted to the Norwegian police university college (1995–2010, N = 6570) and all police-educated staff employed in the Norwegian police (1995–2014, N = 7001). Students and police officers with non-Western immigrant backgrounds have a greater tendency to both dropout of education and leave the police service. Prior academic performance can only partly explain these higher educational dropout rates. Female and males with non-Western immigrant backgrounds have similar dropout patterns. Our results provide a rationale for developing policy aimed at not only recruiting, but also retaining police officers with immigrant backgrounds.
Algorithm for real-time colour mixing of a five-channel LED system while optimising spectral quality parameters
Authors: Eissfeldt A , Khanh TQ
Published: December 2021

Multichannel LED luminaires with more than three channels offer the advantage to vary the spectrum and keeping the chromaticity steady. However, the optimisation calculations of various quality metrics are a challenge for real-time implementation, especially for the limited resources of a luminaire’s microcontroller. Here, we present a method in which a five-channel system is simulated with a quickly solvable 3-channel system by defining virtual channels, each consisting of two LED channels. An analysis of the influence of the parameterisation of the virtual valences on various quality metrics is presented. It shows how these parameters must be set at the time of the mixing calculation, in order to optimise the desired quality aspect. The mixing calculation can thus be carried out in real-time without high hardware requirements and is suitable for further developments, for example, to compensate for colour drift of the LEDs through sensor feedback.
Mortality and Major Adverse Events Improve With Increased Institutional Experience for Fenestrated and Branched Endovascular Aortic Repair
Authors: Doonan Robert-James , Bin-Ayeed Saad , Charbonneau Philippe , Hongku Kiattisak , Mackenzie Kent , Steinmetz Oren , Bayne Jason , Abraham Cherrie , Obrand Daniel , Girsowicz Elie , Gill Heather L.
Published: December 2021

Objective:

Our objective was to evaluate temporal trends in outcomes at our institution in the context a more heterogenous application of fenestrated/branched endovascular aneurysm repair (F/BEVAR).

Methods:

Patient and aneurysm characteristics, procedure details, and postoperative outcomes were collected for consecutive patients undergoing F/BEVAR between 2002 and February 2019 at our institution. Outcomes were compared between tertile 1 (T1, 2002–2010, n=47), T2 (2011–2014, n=47), and T3 (2015-February 2019, n=47).

Results:

We included 141 patients (74.8 ± 8.1 years, 83% male) with a mean follow-up of 28.0 ± 31.6 months. Proportion of patients with hypertension (63.8% T1, 85.1% T3, p=0.009), diabetes (6.4% T1, 29.7% T3, p=0.005), chronic obstructive pulmonary disease (COPD; 27.6% T1, 42.5% T3, p=0.07), and history of stroke (4.2% T1, 17% T3, p=0.07) increased over time. Aneurysm diameter (65.3±11.4mm) and extent (56.0% juxtarenal/pararenal, 22.0% type IV, 22.0% type I-III) did not differ between groups. Custom made devices were implanted in 96.5% of cases with 3.4 ± 0.7 vessels reimplanted/case. There was a trend toward increased history of aortic surgery (p=0.008) and less custom made devices (p=0.007) in T3. Total procedure time (383.5±119.2 minutes T1, 316.2±88.4 T3, p=0.02), contrast volume (222.8±109.1 mL T1, 139.2±62.7ml T3, p<0.0001), and estimated blood loss (601.3±458.1 mL T1, 413.3±317.7 mL T3, p=0.02) decreased over time. Overall 30-day mortality was 6.3%, 10.6%-T1, 6.3%-T2, and 2.1%-T3 (p=0.09). We noted significant improvement in survival over time; 1- and 3-year survival was 79% and 56%, 89% and 83%, and 90% and 90%, for T1, T2, and T3, respectively (p=0.007). In all, 467 of 480 target vessels were revascularized (97.3% success). Reintervention rate (30-day: 13.5%, follow-up: 34.7%) and reintervention free survival was not significantly different between groups. Any major adverse event (MAE) occurred in 36.9% of patients overall with a significant decrease from early (51.1%), mid (34.9%), to late in our experience (25.5%, p=0.03). In multivariate analyses, increasing institutional experience (T3), procedure time, age, and sex were independent predictors of major adverse events.

Conclusion:

We have shown improvement in F/BEVAR outcomes including mortality, MAEs, and procedural metrics with increasing institutional experience. We postulate that a combination of advancements in technique, surgical team and postoperative care experience, graft design and stent technologies, and patient selection contributed to improvement in outcomes.
Resilience and Turnover Intention: The Role of Mindful Leadership, Empathetic Leadership, and Self-Regulation
Authors: Wibowo Amin , Paramita Widya
Published: December 2021

This study investigates the impact of mindful and empathetic leadership on resilience and turnover intention, with self-regulation as a mediating variable. A quantitative survey was administered to 188 nurses dealing with COVID-19’s patients in Indonesia. Data were analyzed using Process v3.5 Andrew F. Hayes in SPSS. This study revealed that mindful leadership reduces turnover intention, and empathetic leadership increases resilience, while mindful leadership does not increase resilience, and empathetic leadership does not lessen turnover intention. We also conclude that self-regulation mediates the relationship between mindful leadership/empathetic leadership and turnover intention/resilience. Despite being limited to the Indonesian context, this research offers several contributions from both theoretical and practical perspectives. First, this research established the importance of mindful and empathetic leadership to promote resilience and reduce the turnover intention of nurses in the time of crisis. Second, we confirmed self-regulation as the mediating variable for those relationships. Practically, we suggest that having empathetic and mindful leaders is effective in supporting nurses to deal with COVID-19 patients.
A cross-sectional study on the tea consumption effects of ankle–brachial index
Authors: Gu Lishuang , Liu Xuemei , Wu Shouling , Chu Kaiyun , Bao Jing-jing
Published: December 2021

Objectives

This thesis aims to explore the relationship between tea consumption and ankle–brachial index (ABI) and further studies the relationship between tea consumption and lower extremity atherosclerosis.

Methods

This is a cross-sectional, epidemiological survey of 17,373 subjects selected from the staff of Kailuan Group who had come to Kailuan General Hospital for a health examination from January 2016 to December 2017. Tea consumption was obtained by questionnaires. ABI was measured using an automated analyzer. The other data, such as age, gender, body mass index (BMI), and so on, was collected on the same day of the health examination results. The relationship between tea drinking habits and ABI was studied using logistic regression and multivariate linear regression analysis.

Results

Among the 17,373 analyzed subjects, the difference in age, gender, BMI, heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), uric acid (UA), C-reactive protein (CRP), fasting blood-glucose (Fbg), and ABI was statistically significant in the tea-drinking group and the nontea-drinking group ( p < 0.05). Multiple logistic regression models revealed that tea consumption was a positive predictor for ABI (odds ratio (OR) = 0.782, confidence interval (CI), 0.615–0.994) ( p < 0.05). Multivariate linear regression analysis of the ABI value showed that frequent tea-drinking has a positive correlation with the ABI value ( p < 0.05).

Conclusions

The higher tea consumption is significantly associated with higher ABI which means less risk for lower extremity atherosclerosis.
The usage and outcomes of dextran in the treatment of acute deep venous thrombosis
Authors: Turhan Soysal , Karaarslan Kemal , Abud Burcin
Published: December 2021

Objectives

In this study, we retrospectively compared the outcomes of patients with acute deep vein thrombosis treated with dextran 40 infusion and unfractionated heparin with those of patients treated with unfractionated heparin alone.

Methods

We evaluated 104 patients with the diagnosis of acute deep vein thrombosis. The pain complaints of the patients at the time of admission and the pain complaints in the calf with dorsiflexion of the foot were evaluated with the visual analogue pain scale, and the calf diameter of affected limbs was measured. Fifty five patients had dextran 40 infusion and unfractionated heparin treatment concomitantly (Group HD), while 49 patients had unfractionated heparin treatment (Group H). Heparin dose was adjusted to obtain 1.5- to 2.5-fold of normal activated partial thromboplastin time in both groups. Oral anticoagulant, warfarin sodium, was administered in the first day and resumed. Unfractionated heparin infusion therapy was resumed until international normalized ratio values of 2–2.5 were obtained. Dextran 40 infusion therapy was administered for 3 days. Calf diameters, current pain, and calf pain at foot dorsiflexion were recorded at 48 h and 72 h. 65 patients were distal, and 39 patients were proximal and popliteal acute DVT. None of the patients had phlegmasia. All were acute DVT.

Results

At 48 and 72 h of therapy, it was determined that the decrease of the calf diameter and the pain were more significant both at 48th and 72nd hours in the Group HD. The calf circumference change, especially at 72 h, was 2.58 ± 0.39 cm in the group receiving heparin + dextran, while it was 1.76 ± 0.56 cm in the group receiving only heparin. ( p = 0.000). While there were only 1.24 ± 1.02 people in the group that received dextran at 72 h, leg pain persisted in 3.35 ± 1.11 people in the other group. ( p = 0.000). Evaluation was made only with calf vein diameter measurement. When patients with Homan’s sign were evaluated for their calf pain at foot dorsiflexion; both groups had decreased pain at 48th and 72nd hours.

Conclusion

In this study, we observed that the use of dextran 40 infusion therapy concomitantly with unfractionated heparin accelerates recovery substantially and decreases patient complaints significantly in early stages. In particular, reduction in leg pain and calf circumference reduction were more adequate in the dextran group. The early decrease in the calf circumference will have clinical consequences such as less heparin intake, earlier return to normal life, and a decrease in the total cost of treatment. Since the antithrombotic and anticoagulant effects of dextran are well known, we think that its use in this treatment as well as venous thromboembolism prophylaxis should be discussed.
How external and internal focus are used in the field: A review
Authors: Yamada Masahiro , Higgins Lauren Q. , Raisbeck Louisa
Published: December 2021

The external focus and internal focus effects on motor performance and skill acquisition have been extensively examined and reviewed in laboratory research. However, the use of attentional focus in the field has not been summarized. Therefore, the present study conducted a systematic review of literature regarding the use of external/internal focus by practitioners (therapists and coaches) and recipients (patients and athletes). From 1999 to 2020, twelve studies examined how external/internal focus were used in the field. Results showed both therapists and coaches predominantly used internal focus; athletes tended to use more internal focus but varied by sports; and attentional focus varied between practice and competition. Additionally, the present review also consistently found that external/internal focus accounted for a small proportion relative to other foci outside the external/internal focus paradigm. Importantly, the differences in results were largely dependent upon the type of assessment ( e.g. closed-ended and open-ended questionnaires). Future research needs to investigate the relative importance of external/internal focus as opposed to other foci, as well as that affect a shift of attentional focus from one type to another.
The importance of perioperative optimisation to facilitate safe regional anaesthesia and their improved outcomes in fracture neck of femur patients
Authors: Gowers Benjamin Thomas Vincent , Greenhalgh Michael Sean , Dyson Kathryn , Iyengar Karthikeyan P , Jain Vijay K , Adam Riad F
Published: December 2021

Background:

Hip fractures are common presentations to orthopaedic departments, and their surgical management often results in blood transfusions. Compared with general anaesthesia, regional anaesthesia reduces the need for transfusions and mortality in the wider surgical population.

Aims:

In hip fracture patients, our primary outcome measure was to examine any relationship between anaesthetic modality and transfusion rates. The secondary outcome measure was to assess the relationship between anaesthetic modality and one-year mortality.

Methods:

A retrospective cohort study of 280 patients was carried out in 2017 and 2018. Data were collected from patient records, local transfusion laboratory and the national hip fracture database.

Results:

A total of 59.6% had regional and 40.4% general anaesthesia. Regional anaesthesia patients were younger with fewer comorbidities (p < .05). About 19.8% regional and 34.5% general anaesthesia patients received transfusions (odds ratio (OR) = 0.47, p < .05); 13.6% were taking anticoagulants and were less likely to receive a regional anaesthetic (31.6% versus 64%, OR = 0.26, p < .05). One-year mortality was 27% for regional and 37% for general anaesthetic patients (OR = 0.64, p = .09).

Conclusion:

Regional anaesthesia halved the risk of blood transfusion. Anticoagulated patients were 74% less likely to receive regional anaesthetics, but had no additional transfusion risk. With optimisation, a larger proportion of patients could have regional anaesthesia.
The democratic deficit of the EU: Breaking the spell of a false analogy
Authors: Malinov Svetoslav
Published: December 2021

The article contains a critique of the concept of the democratic deficit of the EU. Its logical unsustainability is revealed by demonstrating that it is based on the ‘fallacy of false analogy’. Several of the numerous implications of this assertion are elaborated, with a special emphasis on the ‘no-demos thesis’. The article does not treat the idea of the democratic deficit of the EU merely as an analytical concept that is based on a false analogy and thus logically incorrect. For the concept has been persistently used in political debates as one of the most destructive tools against the EU. The concluding section contains a radical proposal for a counter-offensive in favour of European integration.
Delayed Thrombus on Carotid Web: Case Report With Escalation of Treatment
Authors: Kodankandath Thomas V.
Published: December 2021

Carotid artery web is an underrecognized source and is found in about 1-2% of patients with acute ischemic stroke. Although, first described four decades ago, optimal therapy for carotid web is not yet known. Carotid stenting and endarterectomy are increasingly used for carotid web treatment, given its definitive treatment and avoiding the complications associated with anticoagulation. The case reported here is of an ischemic stroke secondary to a mobile thrombus on a carotid web evident on CT angiography and successful definitive treatment with delayed carotid wall stent placement. In young patients who have a diagnosis of ischemic stroke, the carotid web should be on the differential and adequate neuroimaging with either CTA or DSA should be pursued.
Solar power for some? Energy transition injustices in Kerala, India
Authors: Bedi Heather Plumridge
Published: December 2021

The Indian government advocates for a major shift from national reliance on coal to more renewable energy sources. While these aspirations are laudable, a political ecology review reveals the uneven power relations associated with the introduction of renewable energy in the southern Indian state of Kerala. Drawing from fieldwork, research traces how Kerala government solar projects, including schemes to promote rooftop solar, prioritize middle- and upper-class consumers. Historically marginalized communities, including people living below the poverty level and Adivasis (indigenous peoples), are not a priority for the state agency implementing renewable energy and thus are not beneficiaries of cleaner energy. This disconnected approach builds from and exacerbates historical political and resource inequalities and enables the persistence of social and environmental injustices, even while moving towards a lower-carbon future. This model does not allow for all residents to actively engage in decision-making about energy processes and proves to be a missed opportunity to think holistically about development and energy in tandem. Energy democracy provides ideas to disturb this uneven power structure, with cooperatives being one possible way to implement this change. As the case of Kerala underscores, India may undergo an energy transition, but it will not be a just energy transition without significant changes.
Suppression of fibrin(ogen)-driven pathologies in disease models through controlled knockdown by lipid nanoparticle delivery of siRNA
Authors: Juang Lih Jiin , Hur Woosuk S. , Silva Lakmali M. , Strilchuk Amy W. , Francisco Brenton , Leung Jerry , Robertson Madelaine K. , Groeneveld Dafna J. , La Prairie Bridget , Chun Elizabeth M. , Cap Andrew P. , Luyendyk James P. , Palumbo Joseph S. , Cullis Pieter R. , Bugge Thomas H. , Flick Matthew J. , Kastrup Christian J.
Published: December 2021

Fibrinogen plays a pathologic role in multiple diseases. It contributes to thrombosis and modifies inflammatory and immune responses, supported by studies in mice expressing fibrinogen variants with altered function or with a germline fibrinogen deficiency. However, therapeutic strategies to safely and effectively tailor plasma fibrinogen concentration are lacking. Here, we developed a strategy to tune fibrinogen expression by administering lipid nanoparticle (LNP)-encapsulated small interfering RNA (siRNA) targeting the fibrinogen α chain (siFga). Three distinct LNP-siFga reagents reduced both hepatic Fga messenger RNA and fibrinogen levels in platelets and plasma, with plasma levels decreased to 42%, 16%, and 4% of normal within 1 week of administration. Using the most potent siFga, circulating fibrinogen was controllably decreased to 32%, 14%, and 5% of baseline with 0.5, 1.0, and 2.0 mg/kg doses, respectively. Whole blood from mice treated with siFga formed clots with significantly decreased clot strength ex vivo, but siFga treatment did not compromise hemostasis following saphenous vein puncture or tail transection. In an endotoxemia model, siFga suppressed the acute phase response and decreased plasma fibrinogen, D-dimer, and proinflammatory cytokine levels. In a sterile peritonitis model, siFga restored normal macrophage migration in plasminogen-deficient mice. Finally, treatment of mice with siFga decreased the metastatic potential of tumor cells in a manner comparable to that observed in fibrinogen-deficient mice. The results indicate that siFga causes robust and controllable depletion of fibrinogen and provides the proof-of-concept that this strategy can modulate the pleiotropic effects of fibrinogen in relevant disease models.
Characteristics of N400 component elicited in patients who have migraine with aura
Authors: Petrusic Igor , Jovanovic Vojislav , Kovic Vanja , Savic Andrej
Published: December 2021

Background

This study aimed to examine the N400 effect and event-related potentials (ERPs) elicited from congruent and incongruent stimuli in patients who have migraines with aura (MwA).

Methods

A total of 33 MwA patients and 20 healthy controls (HCs) were studied. They were balanced in age (35.12 ± 8.94 vs 34.70 ± 9.59 years, p = 0.872) and sex (69.7 vs 75.0% females, p = 0.761). ERPs were measured in response to both stimuli, where pictures were preceded with an object name that either matched or mismatched with the object. Averaged amplitudes, peaks, peak latencies, difference waves and topography were compared between MwA and HCs.

Results

MwA patients had significantly lower averaged amplitudes at the Fz and F4 sites during incongruent stimuli, as well as reduced peaks at the C3 and Pz sites. Topography showed a more widespread N400 effect over scalp relative to HCs. The difference ERP waveforms did not differ in the N400 effect between groups, but the P600 effect was significantly stronger in the HCs group relative to the MwA group at the Pz (6.52 ± 2.57 vs. 3.50 ± 3.15, p = 0.001) and P4 (5.86 ± 2.79 vs. 3.95 ± 3.64, p = 0.040) sites.

Conclusions

Picture-word matching tasks could serve as a potential new method for the investigation of semantic processing in MwA patients.
Prolonged viral shedding of SARS-CoV-2 and related factors in symptomatic COVID-19 patients: a prospective study
Authors: Long Hui , Zhao Jing , Zeng Hao-Long , Lu Qing-Bin , Fang Li-Qun , Wang Qiang , Wu Qing-Ming , Liu Wei
Published: December 2021

Background

The temporal relationship between SARS-CoV-2 and antibody production and clinical progression remained obscure. The aim of this study was to describe the viral kinetics of symptomatic patients with SARS-CoV-2 infection and identify factors that might contribute to prolonged viral shedding.

Methods

Symptomatic COVID-19 patients were enrolled in two hospitals in Wuhan, China, from whom the respiratory samples were collected and measured for viral loads consecutively by reverse transcriptase quantitative PCR (RT-qPCR) assay. The viral shedding pattern was delineated in relate to the epidemiologic and clinical information.

Results

Totally 2726 respiratory samples collected from 703 patients were quantified. The SARS-CoV-2 viral loads were at the highest level during the initial stage after symptom onset, which subsequently declined with time. The median time to SARS-CoV-2 negativity of nasopharyngeal test was 28 days, significantly longer in patients with older age (> 60 years old), female gender and those having longer interval from symptom onset to hospital admission (> 10 days). The multivariate Cox regression model revealed significant effect from older age (HR 0.73, 95% CI 0.55–0.96), female gender (HR 0.72, 95% CI 0.55–0.96) and longer interval from symptom onset to admission (HR 0.44, 95% CI 0.33–0.59) on longer time to SARS-CoV-2 negativity. The IgM antibody titer was significantly higher in the low viral loads group at 41–60 days after symptom onset. At the population level, the average viral loads were higher in early than in late outbreak periods.

Conclusions

The prolonged viral shedding of SARS-CoV-2 was observed in COVID-19 patients, particularly in older, female and those with longer interval from symptom onset to admission.
Case Report : Li-Fraumeni Syndrome with Central Nervous System Tumors in Two Siblings
Authors: Fang Zishi , Su Yan , Sun Hailang , Ge Ming , Qi Zhan , Hao Chanjuan , Qian Suyun , Ma Xiaoli
Published: December 2021

Background

Li-Fraumeni syndrome (LFS) is a rare autosomal dominant cancer predisposition syndrome caused by germline TP53 gene mutations. It is characterized by high risk of early-onset cancer, and has been confirmed as associated with multiple tumors clinically. So pediatricians should be more alert to LFS in children with tumors. Choroid plexus carcinoma (CPC) is a rare, malignant tumor which account for less than 1% of all central nervous system (CNS) tumors. However, when such tumorigenesis occurs, it is important to be vigilant for the presence of LFS.

Case presentation

The first patient is a 32-month-old boy admitted for convulsions and then was found intracranial space-occupying lesion. Underwent operation, he was diagnosis as choroid plexus carcinoma (WHO Grade III). After 5 months, his elder sister, a 13-year-old girl, was brought to emergency department for confusion and intermittent convulsions. Surgery was performed immediately after head CT examination found the lesion. The pathology result indicated glioblastoma. Because the siblings of the same family have successively suffered from malignant tumors, we performed genetic testing on this family. TP53 gene mutation occurred in both children of these two cases from their father, and their other brother was not spared either. So the two siblings both met the diagnostic criteria of LFS. Then they all received systematic anti-tumor therapy, and follow-up hitherto.

Conclusion

Here we reported a rare LFS case that two siblings were inherited the same TP53 germline mutations from their father. They suffered from choroid plexus carcinoma and glioblastoma and were finally diagnosed with LFS. In this LFS family, the primary tumors of the two children were both central nervous system tumors, which were not reported in the previous literature. It is suggested that clinicians should be alert to LFS related tumors, which is helpful for early diagnosis. Timely detection of TP53 gene is an important way for early diagnosis of LFS, especially in children with tumor. The incidence of secondary tumor in LFS patients is significantly higher, and other family members of the LFS patient also have an increased risk of suffering from the tumors. Therefore, early diagnosis and timely tumor surveillance can obtain better therapeutic effect and prognosis for both proband and their family.
Long-term endoscopic submucosal dissection with postoperative lung injury: a case report
Authors: Zhu Qian-Mei , Tu Hong , Hu Bing , Wang Xiao
Published: December 2021

Background

Endoscopic submucosal dissection (ESD) has been recognized as a safe and minimally invasive technique for the removal of early gastric cancer. Here, we describe a case of extended-duration ESD for a gastric tumor associated with intraoperative perforation and bleeding. Unfortunately, the patient developed acute lung injury (ALI) after the operation.

Case presentation:

A 72-year-old woman received ESD for a gastric tumor under general anesthesia. Preoperatively, endoscopic ultrasonography (EUS) showed a 3.1 × 3.5 cm hypoechoic, well-defined mass at the junction of the antrum and body of the stomach on the greater curvature, originating in the muscularis propria layer. During the ESD procedure, when the submucosal mass was stripped, it was found to be closely adhered to the muscular layer and serosa layer, and a full-thickness incision was performed. The abdominal cavity was gradually filled with carbon dioxide gas, and abdominal puncture was performed to reduce intra-abdominal hypertension (IAH). Because the mass adhered to the greater omentum and there was more bleeding during the operation, a long duration of hemostasis and suturing of the wound was required. The whole operation lasted nearly 9 h, and total blood loss was 800 ml. After surgery, acute lung injury was suspected, and the patient was sent to the intensive care unit (ICU) for further treatment.

Conclusions

The operation time of ESD and IAH caused by perforation are closely related to a poor prognosis. We should pay attention to the impact of operation time on patients and improve awareness regarding protecting important organ functions.
The efficacy of systemic antibiotics as an adjunct to surgical treatment of peri-implantitis: a systematic review
Authors: Øen Malene , Leknes Knut N. , Lund Bodil , Bunæs Dagmar F.
Published: December 2021

Background

Microbial biofilm accumulation is the main cause of peri-implantitis. The majority of surgical peri-implantitis treatment protocols suggests adjunctive use of systemic antibiotics to target specific putative bacteria. The aim of this systematic review was to critically evaluate the adjunctive use of systemically administered antibiotics in surgical treatment of peri-implantitis by reviewing previously published systematic reviews and primary studies.

Methods

A systematic literature search was conducted in four electronic databases (MEDLINE, The Cochrane Library, EMBASE, and Web of Science) for randomised controlled trials, cohort studies, case–control studies, and systematic reviews reporting surgical treatment of peri-implantitis with and without adjunctive systemically administered antibiotic therapy. The included systematic reviews and primary studies were qualitatively assessed using AMSTAR and GRADE, respectively. No restrictions were set for date of publication, journal, or language.

Results

The literature search identified 681 papers. Only seven systematic reviews and two primary studies met the inclusion criteria. Four out of seven included systematic reviews concluded that no evidence exists for use of systemic antibiotics to improve the clinical outcomes in surgical treatment of peri-implantitis. One review did not estimate the level of evidence, one did not clearly state any beneficial effect, whereas one reported a limited adjunctive effect. Further, the two included primary studies did not show a long-term significant benefit of adjunctive use of systemically administrated antibiotics. However, one study reported a short-term adjunctive effect in patients with modified surface implants. Due to heterogeneity in study design, low number of included primary studies, and grade of bias, no meta-analysis was performed.

Conclusion

The use of systemically administered antibiotics as an adjunct to surgical interventions of peri-implantitis cannot be justified as a part of a standard treatment protocol. A pervasive problem is the lack of uniform diagnosis criteria for peri-implantitis, deficient information about patient characteristics, absence of high quality long-term randomised controlled trials, and authors’ declaration on conflict of interest.
Nomogram based on clinical characteristics and serological inflammation markers to predict overall survival of oral tongue squamous cell carcinoma patient after surgery
Authors: Lin Yi-Wei , Kang Wei-Piao , Huang Bin-Liang , Qiu Zi-Han , Wei Lai-Feng , Zhang Biao , Ding Tian-Yan , Luo Yun , Liu Can-Tong , Chu Ling-Yu , Guo Hai-Peng , Xu Yi-Wei , Peng Yu-Hui
Published: December 2021

Background

Oral tongue squamous cell carcinoma (OTSCC) is a prevalent malignant disease that is characterized by high rates of metastasis and postoperative recurrence. The aim of this study was to establish a nomogram to predict the outcome of OTSCC patients after surgery.

Methods

We retrospectively analyzed 169 OTSCC patients who underwent treatments in the Cancer Hospital of Shantou University Medical College from 2008 to 2019. The Cox regression analysis was performed to determine the independent prognostic factors associated with patient’s overall survival (OS). A nomogram based on these prognostic factors was established and internally validated using a bootstrap resampling method.

Results

Multivariate Cox regression analysis revealed the independent prognostic factors for OS were TNM stage, age, lymphocyte-to-monocyte ratio and immunoglobulin G, all of which were identified to create the nomogram. The Akaike Information Criterion and Bayesian Information Criterion of the nomogram were lower than those of TNM stage (292.222 vs. 305.480; 298.444 vs. 307.036, respectively), indicating a better goodness-of-fit of the nomogram for predicting OS. The bootstrap-corrected of concordance index (C-index) of nomogram was 0.784 (95% CI 0.708–0.860), which was higher than that of TNM stage (0.685, 95% CI 0.603–0.767,P = 0.017). The results of time-dependent C-index for OS also showed that the nomogram had a better discriminative ability than that of TNM stage. The calibration curves of the nomogram showed good consistency between the probabilities and observed values. The decision curve analysis also revealed the potential clinical usefulness of the nomogram. Based on the cutoff value obtained from the nomogram, the proposed high-risk group had poorer OS than low-risk group (P < 0.0001).

Conclusions

The nomogram based on clinical characteristics and serological inflammation markers might be useful for outcome prediction of OTSCC patient.
Composition-driven symptom phrase recognition for Chinese medical consultation corpora
Authors: Gu Xuan , Sun Zhengya , Zhang Wensheng
Published: December 2021

Background

Symptom phrase recognition is essential to improve the use of unstructured medical consultation corpora for the development of automated question answering systems. A majority of previous works typically require enough manually annotated training data or as complete a symptom dictionary as possible. However, when applied to real scenarios, they will face a dilemma due to the scarcity of the annotated textual resources and the diversity of the spoken language expressions.

Methods

In this paper, we propose a composition-driven method to recognize the symptom phrases from Chinese medical consultation corpora without any annotations. The basic idea is to directly learn models that capture the composition, i.e., the arrangement of the symptom components (semantic units of words). We introduce an automatic annotation strategy for the standard symptom phrases which are collected from multiple data sources. In particular, we combine the position information and the interaction scores between symptom components to characterize the symptom phrases. Equipped with such models, we are allowed to robustly extract symptom phrases that are not seen before.

Results

Without any manual annotations, our method achieves strong positive results on symptom phrase recognition tasks. Experiments also show that our method enjoys great potential with access to plenty of corpora.

Conclusions

Compositionality offers a feasible solution for extracting information from unstructured free text with scarce labels.