bluuebunny/crossref_metadata_2025 huggingface dataset:
Diagnostic and management strategies for congenital H-type tracheoesophageal fistula: a systematic review
Authors: Sampat Keerthika , Losty Paul D.
Published: January 2021

Background

H type tracheoesophageal fistula (H-TEF) is a rare congenital anomaly. Management may be complicated by late diagnosis and variation(s) in the therapeutic strategy. A systematic review of published studies explores the utility of diagnostic studies, operations and postoperative complications.

Methods

Medline and PubMed database(s) were searched for ALL studies reporting H-TEF during 1997–2020. Using PRISMA methodology, manuscripts were screened for eligibility and reporting.

Results

Forty-seven eligible studies were analysed. Primary diagnosis varied widely with surgeons performing oesophagography and trachea-bronchoscopy. Preoperative localisation techniques included fluoroscopy, guidewire placement and catheterisation. A cervical approach (209 of 272 cases), as well as thoracotomy, thoracoscopy and endoscopic fistula ligation, were all described. Morbidity included fistula recurrence (1.7%), leak (2%), tracheomalacia (3.4%) and respiratory sequelae (1%). The major adverse complication in all studies was vocal cord palsy secondary to laryngeal nerve injury (18.5%) yet strikingly few centres routinely reported undertaking vocal cord screening pre or postoperatively.

Conclusion

This study shows that paediatric surgeons record low volume activity with H type tracheoesophageal fistula. Variation(s) in clinical practice are widely evident. Laryngeal nerve injury and its subsequent management warrant special consideration. Care pathways may offset attendant morbidity and define 'best practice.'
How to distinguish between different cell lineages sharing common markers using combinations of double in-situ-hybridization and immunostaining in avian embryos: CXCR4-positive mesodermal and neural crest-derived cells
Authors: Yahya Imadeldin , Böing Marion , Brand-Saberi Beate , Morosan-Puopolo Gabriela
Published: January 2021

Cell migration plays a crucial role in early embryonic development. The chemokine receptor CXCR4 has been reported to guide migration of neural crest cells (NCCs) to form the dorsal root ganglia (DRG) and sympathetic ganglia (SG). CXCR4 also plays an important part during the formation of limb and cloacal muscles. NCCs migration and muscle formation during embryonic development are usually considered separately, although both cell lineages migrate in close neighbourhood and have markers in common. In this study, we present a new method for the simultaneous detection of CXCR4, mesodermal markers and NCCs markers during chicken embryo developmental stages HH18–HH25 by combining double whole-mount in situ hybridization (ISH) and immunostaining on floating vibratome sections. The simultaneous detection of CXCR4 and markers for the mesodermal and neural crest cells in multiple labelling allowed us to compare complex gene expression patterns and it could be easily used for a wide range of gene expression pattern analyses of other chicken embryonic tissues. All steps of the procedure, including the preparation of probes and embryos, prehybridization, hybridization, visualization of the double labelled transcripts and immunostaining, are described in detail.
Visualisation of cholesterol and ganglioside GM1 in zebrafish models of Niemann–Pick type C disease and Smith–Lemli–Opitz syndrome using light sheet microscopy
Authors: Cook Sophie R. , Bladen Cerys , Smith Johanna , Maguire Emily , Copner Jordan , Fenn Gareth D. , Wager Kim , Waller-Evans Helen , Lloyd-Evans Emyr
Published: January 2021

Lysosomal storage diseases are the most common cause of neurodegeneration in children. They are characterised at the cellular level by the accumulation of storage material within lysosomes. There are very limited therapeutic options, and the search for novel therapies has been hampered as few good small animal models are available. Here, we describe the use of light sheet microscopy to assess lipid storage in drug and morpholino induced zebrafish models of two diseases of cholesterol homeostasis with lysosomal dysfunction: First, Niemann–Pick type C disease (NPC), caused by mutations in the lysosomal transmembrane protein NPC1, characterised by intralysosomal accumulation of cholesterol and several other lipids. Second, Smith–Lemli–Opitz syndrome (SLOS), caused by mutations in 7-dehydrocholesterol reductase, which catalyses the last step of cholesterol biosynthesis and is characterised by intralysosomal accumulation of dietary cholesterol. This is the first description of a zebrafish SLOS model. We find that zebrafish accurately model lysosomal storage and disease-specific phenotypes in both diseases. Increased cholesterol and ganglioside GM1 were observed in sections taken from NPC model fish, and decreased cholesterol in SLOS model fish, but these are of limited value as resolution is poor, and accurate anatomical comparisons difficult. Using light sheet microscopy, we were able to observe lipid changes in much greater detail and identified an unexpected accumulation of ganglioside GM1 in SLOS model fish. Our data demonstrate, for the first time in zebrafish, the immense potential that light sheet microscopy has in aiding the resolution of studies involving lysosomal and lipid disorders.
Voluntary activity reverses spermidine-induced myocardial fibrosis and lipid accumulation in the obese male mouse
Authors: Mühlfeld Christian , Pfeiffer Clara , Schneider Vanessa , Bornemann Melanie , Schipke Julia
Published: January 2021

Obesity due to high calorie intake induces cardiac hypertrophy and dysfunction, thus contributing to cardiovascular morbidity and mortality. Recent studies in aging suggest that oral supplementation with the natural polyamine spermidine has a cardioprotective effect. Here, the hypothesis was tested that spermidine or voluntary activity alone or in combination protect the heart from adverse effects induced by obesity. Therefore, C57Bl/6 mice (n = 8–10 per group) were subjected to control or high fat diet (HFD) and were left untreated, or either received spermidine via drinking water or were voluntarily active or both. After 30 weeks, the mice were killed and the left ventricle of the hearts was processed for light and electron microscopy. Design-based stereology was used to estimate parameters of hypertrophy, fibrosis, and lipid accumulation. HFD induced cardiac hypertrophy as demonstrated by higher volumes of the left ventricle, cardiomyocytes, interstitium, myofibrils and cardiomyocyte mitochondria. These changes were not influenced by spermidine or voluntary activity. HFD also induced myocardial fibrosis and accumulation of lipid droplets within cardiomyocytes. These HFD effects were enhanced in spermidine treated animals but not in voluntarily active mice. This was even the case in voluntarily active mice that received spermidine. In conclusion, the data confirm the induction of left ventricular hypertrophy by high-fat diet and suggest that—under high fat diet—spermidine enhances cardiomyocyte lipid accumulation and interstitial fibrosis which is counteracted by voluntary activity.
Tools of the trade: studying actin in zebrafish
Authors: Pinto Clyde Savio , Mishima Masanori , Sampath Karuna
Published: January 2021

Actin is a conserved cytoskeletal protein with essential functions. Here, we review the state-of-the-art reagents, tools and methods used to probe actin biology and functions in zebrafish embryo and larvae. We also discuss specific cell types and tissues where the study of actin in zebrafish has provided new insights into its functions.
Thioredoxin 1 is upregulated in the bone and bone marrow following experimental myocardial infarction: evidence for a remote organ response
Authors: Godoy José R. , Pittrich Sarah , Slavic Svetlana , Lillig Christopher Horst , Hanschmann Eva-Maria , Erben Reinhold G.
Published: January 2021

Ischemia and reperfusion events, such as myocardial infarction (MI), are reported to induce remote organ damage severely compromising patient outcomes. Tissue survival and functional restoration relies on the activation of endogenous redox regulatory systems such as the oxidoreductases of the thioredoxin (Trx) family. Trxs and peroxiredoxins (Prxs) are essential for the redox regulation of protein thiol groups and for the reduction of hydrogen peroxide, respectively. Here, we determined whether experimental MI induces changes in Trxs and Prxs in the heart as well as in secondary organs. Levels and localization of Trx1, TrxR1, Trx2, Prx1, and Prx2 were analyzed in the femur, vertebrae, and kidneys of rats following MI or sham surgery. Trx1 levels were significantly increased in the heart (P = 0.0017) and femur (P < 0.0001) of MI animals. In the femur and lumbar vertebrae, Trx1 upregulation was detected in bone-lining cells, osteoblasts, megakaryocytes, and other hematopoietic cells. Serum levels of Trx1 increased significantly 2 days after MI compared to sham animals (P = 0.0085). Differential regulation of Trx1 in the bone was also detected by immunohistochemistry 1 month after MI. N-Acetyl-cysteine treatment over a period of 1 month induced a significant reduction of Trx1 levels in the bone of MI rats compared to sham and to MI vehicle. This study provides first evidence that MI induces remote organ upregulation of the redox protein Trx1 in the bone, as a response to ischemia–reperfusion injury in the heart.
Protein expression pattern of calcium-responsive transactivator in early postnatal and adult testes
Authors: Du Ana , Li Li , Jiao Zhaoshuang , Zhu Gaochun , Peng Ting , Li He
Published: January 2021

Calcium-responsive transactivator (CREST), a nuclear protein highly expressed in postmitotic neurons, is involved in the regulation of cell cycle, differentiation and dendritic development of neuronal cells. Its mRNA has been detected in the testis of adult rat, whilst its protein expression and distribution pattern in the testis remain to be elucidated. In this study, we examined the distribution of CREST in the adult testes of both rats and human as well as the expression pattern of CREST in the testes of postnatal developing rats. In the adult testes of both human and rats, immunohistochemical analysis revealed that CREST was selectively distributed in the mature Sertoli cells but not in the spermatogenic cells. In the testes of postnatal developmental rats, CREST was expressed not only in Sertoli cells but also in the gonocytes and spermatogenic cells at the initial stage of spermatogenic cell differentiation. CREST immunoreactivity continued to increase in Sertoli cells during differentiation, reaching its peak in adulthood. However, CREST immunostaining intensity dramatically decreased as the spermatogenic cells differentiate, disappearing in the post-differentiation stage. Furthermore, Brg1 and p300, two CREST-interacting proteins ubiquitously expressed in the body, are found to be colocalized with CREST in the spermatogenic epithelial cells including Sertoli cells. The unique expression pattern of CREST in developing testis suggests that CREST might play regulatory roles in the differentiation of spermatogenic epithelial cells. The Sertoli cell-specific expression of CREST in the adulthood hints that CREST might be a novel biomarker for the mature Sertoli cells.
A combinatorial method to visualize the neuronal network in the mouse spinal cord: combination of a modified Golgi-Cox method and synchrotron radiation micro-computed tomography
Authors: Jiang Liyuan , Cao Yong , Yin Xianzhen , Ni Shuangfei , Li Miao , Li Chengjun , Luo Zixiang , Lu Hongbin , Hu Jianzhong
Published: January 2021

Exploring the three-dimensional (3D) morphology of neurons is essential to understanding spinal cord function and associated diseases comprehensively. However, 3D imaging of the neuronal network in the broad region of the spinal cord at cellular resolution remains a challenge in the field of neuroscience. In this study, to obtain high-resolution 3D imaging of a detailed neuronal network in the mass of the spinal cord, the combination of synchrotron radiation micro-computed tomography (SRμCT) and the Golgi-cox staining were used. We optimized the Golgi-Cox method (GCM) and developed a modified GCM (M-GCM), which improved background staining, reduced the number of artefacts, and diminished the impact of incomplete vasculature compared to the current GCM. Moreover, we achieved high-resolution 3D imaging of the detailed neuronal network in the spinal cord through the combination of SRμCT and M-GCM. Our results showed that the M-GCM increased the contrast between the neuronal structure and its surrounding extracellular matrix. Compared to the GCM, the M-GCM also diminished the impact of the artefacts and incomplete vasculature on the 3D image. Additionally, the 3D neuronal architecture was successfully quantified using a combination of SRμCT and M-GCM. The SRμCT was shown to be a valuable non-destructive tool for 3D visualization of the neuronal network in the broad 3D region of the spinal cord. Such a combinatorial method will, therefore, transform the presentation of Golgi staining from 2 to 3D, providing significant improvements in the 3D rendering of the neuronal network.
An introduction to perfect and imperfect competition via bilateral oligopoly
Authors: Dickson Alex , Tonin Simone
Published: January 2021

This paper explores the study of bilateral oligopoly, in which both sellers and buyers have substantial influence on the market. We lead readers coherently through the key results that emerge from the literature on bilateral oligopoly by means of worked examples based on the same underlying two commodity exchange economy, along with broader consideration of the relevant literature. This allows us to concisely compare the different equilibrium outcomes when agents act simultaneously vs sequentially, and when some/all agents are assumed to behave competitively, giving the reader much-needed straightforward access to the results of this challenging literature.
Maxillary expansion or contraction and occlusal contact adjustment: effectiveness of current aligner treatment
Authors: Riede Ulrike , Wai Sandra , Neururer Sabrina , Reistenhofer Bärbel , Riede Gregor , Besser Katharina , Crismani Adriano
Published: January 2021

Objectives

To evaluate the precision of aligner (Invisalign®) treatment with the current material (SmartTrack®) in achieving expansion or contraction of the maxilla and occlusal contacts as simulated in the proprietary planning software (ClinCheck®, CC).

Materials and methods

Thirty patients thus treated were retrospectively evaluated. Four maxillary models were analyzed per patient: a pretreatment model, a scan-based CC model, a posttreatment clinical model, and a CC model reflecting the treatment outcome as initially simulated. Thirteen transverse parameters were measured on each model separately by two investigators. Occlusal contacts were also analyzed.

Results

The measuring method was validated by both investigators arriving at similar results for the effectiveness by which the simulated treatment goals had been clinically achieved. Significant differences (p < 0.05; Wilcoxon signed-rank test) were observed for transfer precision from the casts to the planning software and between the simulated and clinical outcomes. Intense occlusal contacts in the simulations materialized less common (≈ 2%) than ideal contacts (≈ 60%) in the clinical outcomes.

Conclusions

The effectiveness of achieving the simulated transverse goals was 45% and was generally not found to be better with SmartTrack® than with the previously used Ex30® material. Out of 100 simulated occlusal contacts, 40 will never materialize, and achieving around 60 will adequately ensure a clinically favorable contact pattern.

Clinical relevance

With the caveat that any overcorrection will to some extent reduce the precision, it seems perfectly possible to make deliberate use of overcorrection in current aligner therapies for transverse maxillary expansion or contraction.
Reversible severe glycogenic hepatopathy in type 1 diabetes
Authors: de Laffolie Jan , Kamrath Clemens , Burchert Diana , Böttcher Claudia , Wudy Stefan Alexander , Zimmer Klaus-Peter
Published: January 2021

Case presentation

We report a case of severe glycogenic hepatopathy in a 17-year-old boy with poorly controlled type 1 diabetes. On presentation, major findings included unexplained pronounced hepatomegaly and increased liver enzymes, ferritin, and triglycerides. Histology and electron microscopy evaluation showed severe glycogen storage, steatosis, and signs of fibrosis, resembling the histomorphological findings of Mauriac syndrome. After information about the nature of the disease and intensification of insulin therapy with insulin pump, liver enzymes, ferritin, and triglycerides normalized within 1 month.

Conclusion

Glycogenic hepatopathy is a rare but important potential complication in poorly controlled juvenile diabetic patients. With improved metabolic control, it is fully reversible.
Vacuum-Assisted Hot-Forming Using Tailored Laminate Temperature
Authors: Grankäll Tommy , Hallander Per , Åkermo Malin
Published: January 2021

A non-isothermal vacuum assisted hot-forming process using tailored laminate temperature is introduced. By using process simulation and manufacturing experiments, improved laminate quality is achieved compared to the standard hot-forming process. Furthermore, it is also shown that the manufacturing time in the clean room can be reduced to one tenth of the standard process time. In this study 8.4 mm thick quasi-isotropic laminates from unidirectional prepreg were laid up flat with an automatic tape laying machine and hot-formed to a U-shaped laminate. The laminates were then cured in a concave mould with standard bag on the inside. A complete tailored temperature hot-forming cycle of 7.5 min produced a very good final laminate quality with a total thickness variation as low as 4.0% and without wrinkles or indications of porosity. With a 4 min hot-forming cycle the thickness variation was also acceptable at 8%.
Sol–gel based synthesis and biological properties of zinc integrated nano bioglass ceramics for bone tissue regeneration
Authors: Paramita Pragyan , Ramachandran Murugesan , Narashiman Srinivasan , Nagarajan Selvamurugan , Sukumar Dinesh Kumar , Chung Tze-Wen , Ambigapathi Moorthi
Published: January 2021

Bone is a flexible and electro active tissue that is vulnerable to various traumatic injuries. The self-healing of damaged bone tissue towards reconstruction is limited due to the lack of proper niche compliances. Nevertheless, the classical grafting techniques like autograft/allograft for bone repair pose challenges like bacterial infections and donor-site morbidity with unsatisfactory outcomes. The use of appropriate biomaterial with osteogenic potential can meet these challenges. In this regard, bioactive glass ceramics is widely used as a bone filler or graft material because of its bonding affinity to bone leading towards bone reconstruction applications without the challenge of post implant infections. Hence, the current study is aimed at addressing this potentiality of zinc (Zn) for doped the bioglass at nano-scale advantages for bone tissue repair. Since, Zn has been demonstrated to have not only antibacterial property but also the stimulatory effect on osteoblasts differentiation, mineralization by enhancing the osteogenic genes expression. In view of these, the present study is focused on sol–gel synthesis and pysico-chemical characterization of Zinc-doped bioglass nanoparticles (Zn-nBGC) and also analyzing its biological implications. The surface morphological and physiochemical characterizations using SEM, EDX, FT-IR and XRD analysis has shown the increased surface area of Zn-nBGC particles providing a great platform for biomolecular interaction, cytocompatibility, cell proliferation and osteogenic differentiation. The obtaining hydroxy apatite groups have initiated in vitro mineralization towards osteogenic lineage formation. Zn has not only involved in enhancing cellular actions but also strengthen the ceramic nanoparticles towards antibacterial application. Hence the finding suggests a biomaterial synthesis of better biomaterial for bone tissue engineering application by preventing post-operative bacterial infection.
Characterization and cytocompatibility of 3D porous biomimetic scaffold derived from rabbit nucleus pulposus tissue in vitro
Authors: Zhang Yu , Tan Wei , Wu Mingxin , Sun Jin , Cao Wei , Zhou Chu-Song , Wu You
Published: January 2021

Intervertebral disc (IVD) degeneration is one of the most important causes of lower back pain. Tissue engineering provides a new method for the experimental treatment of degenerative disc diseases. This study aims to develop a natural, acellular, 3D interconnected porous scaffold derived from the extracellular matrix (ECM) of nucleus pulposus. The nucleus pulposus (NP) was decellularized by sequential detergent-nuclease methods, including physical crushing, freeze-drying and cross-linking. These 3D porous scaffolds were fabricated with a high porosity of (81.28 ± 4.10)%, an ideal pore size with appropriate mechanical properties. Rabbit bone marrow mesenchymal stem cells (rBMSCs) were seeded and cultured on the scaffolds. And the mechanical tests showed the compressive elastic modulus of the scaffolds cultured for 4 weeks reached 0.12 MPa, which was better than that of the scaffolds cultured for 2 weeks (0.07 MPa) and that of the control group (0.04 MPa). Scanning electron microscopy (SEM), histological assays, molecular biology assays revealed that the scaffolds could provide an appropriate microstructure and environment for the adhesion, proliferation, migration and secretion of seeded cells in vitro. As assays like histology, immunohistochemistry and the real-time qRT-PCR showed, NP-like tissues were preliminarily formed. In conclusion, the 3D porous scaffold derived from NP ECM is a potential biomaterial for the regeneration of NP tissues.
Inhomogeneous Distribution of Polytetrafluorethylene in Gas Diffusion Layers of Polymer Electrolyte Fuel Cells
Authors: Froning Dieter , Reimer Uwe , Lehnert Werner
Published: January 2021

Polymer electrolyte fuel cells require gas diffusion layers that can efficiently distribute the feeding gases from the channel structure to the catalyst layer on both sides of the membrane. On the cathode side, these layers must also allow the transport of liquid product water in a counter flow direction from the catalyst layer to the air channels where it can be blown away by the air flow. In this study, two-phase transport in the fibrous structures of a gas diffusion layer was simulated using the lattice Boltzmann method. Liquid water transport is affected by the hydrophilic treatment of the fibers. Following the assumption that polytetrafluorethylene is preferably concentrated at the crossings of fibers, the impact of its spatial distribution is analyzed. Both homogeneous and inhomogeneous distribution is investigated. The concentration of polytetrafluorethylene in the upstream region is of advantage for the fast transport of liquid water through the gas diffusion layer. Special attention is given to the topmost fiber layer. Moreover, polytetrafluorethylene covering the fibers leads to large contact angles.
Efficient simultaneous removal of heavy metals and polychlorobiphenyls from a polluted industrial site by washing the soil with natural humic surfactants
Authors: Piccolo Alessandro , De Martino Antonio , Scognamiglio Francesco , Ricci Roberto , Spaccini Riccardo
Published: January 2021

We evaluated the effectiveness of natural organic surfactants such as humic acids (HA) from lignite to simultaneously wash heavy metals (HM) and polychlorobiphenyls (PCB) from a heavily contaminated industrial soil of northern Italy. Supramolecular HA promote in solution a micelle-like structure, where recalcitrant apolar organic xenobiotics are repartitioned from surfaces of soil particles during soil washing process. Concomitantly, the HA acidic functional groups enable a simultaneous complexation of HM. A single soil washing with HA removed 68 and 75% of PCB congeners for 1:1 and 10:1 solution/soil ratios, respectively. The same HA washing simultaneously and efficiently removed a cumulative average of 47% of total HM, with a maximum of 57 and 67% for Hg and Cu, respectively. We showed that washing a highly polluted soil with HA solution not only is an effective and rapid soil remediation technique but also simultaneously removes both HM and persistent organic pollutants (POP). Soil washing by humic biosurfactants is also a sustainable and eco-friendly technology, since, contrary to synthetic surfactants and solvents used in conventional washing techniques, it preserves soil biodiversity, promotes natural attenuation of unextracted POP, and accelerates further soil reclamation techniques such as bio- or phytoremediation.
Discrete element analysis of the punching behaviour of a secured drapery system: from laboratory characterization to idealized in situ conditions
Authors: Pol Antonio , Gabrieli Fabio , Brezzi Lorenzo
Published: January 2021

In this work, the mechanical response of a steel wire mesh panel against a punching load is studied starting from laboratory test conditions and extending the results to field applications. Wire meshes anchored with bolts and steel plates are extensively used in rockfall protection and slope stabilization. Their performances are evaluated through laboratory tests, but the mechanical constraints, the geometry and the loading conditions may strongly differ from the in situ conditions leading to incorrect estimations of the strength of the mesh. In this work, the discrete element method is used to simulate a wire mesh. After validation of the numerical mesh model against experimental data, the punching behaviour of an anchored mesh panel is investigated in order to obtain a more realistic characterization of the mesh mechanical response in field conditions. The dimension of the punching element, its position, the anchor plate size and the anchor spacing are varied, providing analytical relationships able to predict the panel response in different loading conditions. Furthermore, the mesh panel aspect ratio is analysed showing the existence of an optimal value. The results of this study can provide useful information to practitioners for designing secured drapery systems, as well as for the assessment of their safety conditions.
Prioritising Targets for School-Based ADHD Interventions: A Delphi Survey
Authors: Perry Roisin Carlotta , Ford Tamsin Jane , O’Mahen Heather , Russell Abigail Emma
Published: January 2021

Many studies have investigated the effectiveness of school-based ADHD interventions at modifying different social, emotional and behavioural target outcomes. However, there is a lack of evidence about which targets stakeholders perceive to be most important. This study sought to obtain consensus on which outcomes are perceived to be most important. A total of 114 people with ADHD, educational professionals, parents of children with ADHD, clinicians and researchers participated in a Delphi survey with 3 rounds. The importance of 52 intervention targets was rated on a scale from 0 to 8 (8 being extremely important). Consensus was reached if >70% of a stakeholder group rated a target as between 6–8 and <15% rated it as 0–2. Targets were dropped from subsequent rounds if more than 50% of stakeholder groups rated it as 0–5. Targets that all four stakeholder groups reached consensus on in any round were automatically included in our final outcome set. Comments were analysed using Thematic Analysis. All four stakeholder groups reached consensus on the importance of seven targets: ability to pay attention, conflict with teachers and peers, executive functioning, global functioning and quality of life, inattention symptoms, organisation skills and self-esteem. Four overarching themes were identified: Complexity of ADHD, Relationships, School Context, and What ADHD means to me. School-based ADHD interventions should target outcomes identified as most important to those who stand to benefit from such interventions. Some outcomes prioritised by our participants have not yet been targeted in school-based ADHD interventions. Implications of our findings for intervention and research design are discussed.
Climate Change Projection in the Twenty-First Century Simulated by NIMS-KMA CMIP6 Model Based on New GHGs Concentration Pathways
Authors: Sung Hyun Min , Kim Jisun , Shim Sungbo , Seo Jeong-byn , Kwon Sang-Hoon , Sun Min-Ah , Moon Hyejin , Lee Jae-Hee , Lim Yoon-Jin , Boo Kyung-On , Kim Youngmi , Lee Johan , Lee Jiwoo , Kim Jun-su , Marzin Charline , Byun Young-Hwa
Published: January 2021

The National Institute of Meteorological Sciences-Korea Meteorological Administration (NIMS-KMA) has participated in the Coupled Model Inter-comparison Project (CMIP) and provided long-term simulations using the coupled climate model. The NIMS-KMA produces new future projections using the ensemble mean of KMA Advanced Community Earth system model (K-ACE) and UK Earth System Model version1 (UKESM1) simulations to provide scientific information of future climate changes. In this study, we analyze four experiments those conducted following the new shared socioeconomic pathway (SSP) based scenarios to examine projected climate change in the twenty-first century. Present day (PD) simulations show high performance skill in both climate mean and variability, which provide a reliability of the climate models and reduces the uncertainty in response to future forcing. In future projections, global temperature increases from 1.92 °C to 5.20 °C relative to the PD level (1995–2014). Global mean precipitation increases from 5.1% to 10.1% and sea ice extent decreases from 19% to 62% in the Arctic and from 18% to 54% in the Antarctic. In addition, climate changes are accelerating toward the late twenty-first century. Our CMIP6 simulations are released to the public through the Earth System Grid Federation (ESGF) international data sharing portal and are used to support the establishment of the national adaptation plan for climate change in South Korea.
Uncertainty analysis of discharge coefficient of circular crested weirs
Authors: Parsaie Abbas , Haghiabi Amir Hamzeh
Published: January 2021

The circular crested weir (CCW) has been introduced as weirs having a high discharge coefficient (Cd). The ratio of flow head to the radius of the crest (H/R) is the most important parameter affecting the Cd, that the $${\text{Cd}} \approx a\left( {H/R} \right)^{b}$$

Cd
≈
a

H
/
R

b

can mathematical model their relation. In this study, the parameters of the Cd formula (i.e., a and b) were uncertainty analyzed using Monte Carlo (MC) and Bootstrap methods (BM). To perform these methods, some of the built-in functions of Excel software were utilized. The results declared that the average values of a and b were 1.187 and 0.140. The outcome of the MC method showed that the range of a and b at 95% confidence interval changed between 1.179 to 1.194 and 0.134 to 0.146, respectively, while at the same confidence interval the BM ranged from 1.187 to 1.200 and 0.133 to 0.147.
Enhancement strategies for transdermal drug delivery systems: current trends and applications
Authors: Ramadon Delly , McCrudden Maeliosa T. C. , Courtenay Aaron J. , Donnelly Ryan F.
Published: January 2021

Transdermal drug delivery systems have become an intriguing research topic in pharmaceutical technology area and one of the most frequently developed pharmaceutical products in global market. The use of these systems can overcome associated drawbacks of other delivery routes, such as oral and parenteral. The authors will review current trends, and future applications of transdermal technologies, with specific focus on providing a comprehensive understanding of transdermal drug delivery systems and enhancement strategies. This article will initially discuss each transdermal enhancement method used in the development of first-generation transdermal products. These methods include drug/vehicle interactions, vesicles and particles,stratum corneummodification, energy-driven methods andstratum corneumbypassing techniques. Through suitable design and implementation of activestratum corneumbypassing methods, notably microneedle technology, transdermal delivery systems have been shown to deliver both low and high molecular weight drugs. Microneedle technology platforms have proven themselves to be more versatile than other transdermal systems with opportunities for intradermal delivery of drugs/biotherapeutics and therapeutic drug monitoring. These have shown that microneedles have been a prospective strategy for improving transdermal delivery systems.

Graphical abstract
Public Actors Without Public Values: Legitimacy, Domination and the Regulation of the Technology Sector
Authors: Taylor Linnet
Published: January 2021

The scale and asymmetry of commercial technology firms’ power over people through data, combined with the increasing involvement of the private sector in public governance, means that increasingly, people do not have the ability to opt out of engaging with technology firms. At the same time, those firms are increasingly intervening on the population level in ways that have implications for social and political life. This creates the potential for power relations of domination, and demands that we decide what constitutes the legitimacy to act on the public. Business ethics and private law are not designed to answer these questions, which are primarily political. If people have lost the right to disengage with commercial technologies, we may need to hold the companies that offer them to the same standards to which we hold the public sector. This paper first defines the problem and demonstrates that it is significant and widespread, and then argues for the development of an overarching normative framework for what constitutes non-domination with regard to digital technologies. Such a framework must involve a nuanced idea of political power and accountability that can respond not only to the legality of corporate behaviour, but to its legitimacy.
Comparative study of hard X-ray undulator beamline performance in the Korean 4GSR and the PLS-II
Authors: Cho Byeong-Gwan , Kim Yongsam , Shin Seunghwan , Koo Tae-Yeong
Published: January 2021

A new light source based on the electron storage ring, dubbed the “diffraction-limited storage ring” (DLSR) to keep the full intrinsic wave nature of X-rays had been proposed since the early stage of storage ring history and has finally been developed successfully, and an upgrade and a new construction programs have now chosen in the worldwide synchrotron facilities. The construction of the so-called “4th generation storage ring” (4GSR), which is a newly-coined term aiming in the same direction, was decided in Korea. The Korean 4GSR is expected to be 10–100 times brighter than the Pohang Light Source-II (PLS-II). Hard X-ray undulator beamlines will benefit from the 4GSR due to its low emittance approaching the diffraction limit. In the PLS-II, more than 10 hard X-ray undulator beamlines are currently in operation. We present a comparative study of the representative hard X-ray undulator beamlines by using the cutting-edge diffraction-spectroscopy techniques in the PLS-II and the 4GSR for better understanding the upcoming light source in Korea. The figures-of-merit of the two specific experimental techniques, resonant inelastic X-ray scattering (RIXS) and resonant X-ray emission spectroscopy (RXES), are discussed for comparison of the two light sources. Both RIXS and RXES are sometimes referred to as a “renaissance” in X-ray science and are, therefore, strongly expected to be adopted in the 4GSR beamlines.
Development of a Remote Online Collaborative Medical School Pathology Curriculum with Clinical Correlations, across Several International Sites, through the Covid-19 Pandemic
Authors: Guiter Gerardo E. , Sapia Sandra , Wright Alexander I. , Hutchins Gordon G. A. , Arayssi Thurayya
Published: January 2021

Introduction

Due to the Covid-19 social distancing restrictions, in March 2020, Weill Cornell Medicine-Qatar decided to replace students’ clinical instruction with novel online electives. Hence, we implemented an innovative online and remote pathology curriculum, anchored on virtual microscopy and Zoom videoconferencing: ideal tools to support online teaching.

Objective

To assess a new curriculum implementation at Weill Cornell Medicine-Qatar.

Materials and Methods

This for-credit, 2-week elective included 6 synchronous Zoom sessions where complex clinicopathological cases were discussed in small groups. We used open access digital microscopy slides from the University of Leeds’ Virtual Pathology Library (http://www.virtualpathology.leeds.ac.uk/slides/library/). Students independently prepared for these sessions by reviewing cases, slides, readings, and questions in advance (asynchronous self-directed learning anchored on a flipped classroom model), and wrote a final review of a case. An assessment and feedback were given to each student.

Results

Four elective iterations were offered to a total of 29 students, with learners and faculty spread over 4 countries. During the Zoom sessions, students controlled the digital slides and offered their own diagnoses, followed by group discussions to strengthen autonomy and confidence. We surveyed learners about the elective’s performance (program evaluation). Students conveyed high levels of satisfaction about the elective’s overall quality, their pathology learning and online interactions, with minimal challenges related to the remote nature of the course.

Discussion and Conclusions

Technological innovations mitigate sudden disruptions in medical education. A remote curriculum allows instructionat any distance, at any time, from anywhere,enhancing educational exchanges, flexibility and globalization in medical education.
Directional correlation coefficient measures for Pythagorean fuzzy sets: their applications to medical diagnosis and cluster analysis
Authors: Lin Mingwei , Huang Chao , Chen Riqing , Fujita Hamido , Wang Xing
Published: January 2021

Compared to the intuitionistic fuzzy sets, the Pythagorean fuzzy sets (PFSs) can provide the decision makers with more freedom to express their evaluation information. There exist some research results on the correlation coefficient between PFSs, but sometimes they fail to deal with the problems of disease diagnosis and cluster analysis. To tackle the drawbacks of the existing correlation coefficients between PFSs, some novel directional correlation coefficients are put forward to compute the relationship between two PFSs by taking four parameters of the PFSs into consideration, which are the membership degree, non-membership degree, strength of commitment, and direction of commitment. Afterwards, two practical examples are given to show the application of the proposed directional correlation coefficient in the disease diagnosis, and the application of the proposed weighted directional correlation coefficient in the cluster analysis. Finally, they are compared with the previous correlation coefficients that have been developed for PFSs.
Neutrosophic fuzzy goal programming approach in selective maintenance allocation of system reliability
Authors: Kamal Murshid , Modibbo Umar Muhammad , AlArjani Ali , Ali Irfan
Published: January 2021

Selective maintenance problem plays an essential role in reliability optimization decision-making problems. Systems are a configuration of several components, and there are situations the system needs small intervals or break for maintenance actions, during the intervals expert carried out the maintenance actions to replace or repair the deteriorated components of the systems. Because of the uncertainty associated with the component’s operational time, failure, and next mission duration create a new challenge in determining optimal components allocation and evaluating future missions successfully. In this paper, a multi-objective selective maintenance allocation problem is formulated with fuzzy parameters under neutrosophic environment. A new defuzzification technique is introduced based on beta distribution to convert fuzzy parameters into crisp values. The neutrosophic goal programming technique is used to determine the compromise allocation of replaceable and repairable components based on the system reliability optimization. A numerical illustration is used to validate the model and ascertain its effectiveness. The result is compared with two other approaches and found to be better. The method is flexible and straightforward and can be solved using any available commercial packages. The extension of the concept can be useful to other complex system reliability optimization.
An Informal Education Intervention in Response to the Covid-19 Pandemic: Homework Mentorships in a Berlin Refugee Shelter
Authors: O’Connell Courtney , Lucić Luka
Published: January 2021

The Covid-19 pandemic and resulting damage is often portrayed in staggering numbers and statistics. This article offers, by contrast, a personal and qualitative account of employees, volunteers, and young residents at a refugee home in Berlin, Germany. Through the story of a boy who has spent the past 4 years in several of Berlin’s 84 remaining refugee accommodations, we examine the inequalities that already existed in Germany and how the pandemic has exacerbated them. To provide ample context, we critically assess the so-called Welcome Classes that children and teens have been attending since their arrival to the country in or around 2015 and argue that the segregation experienced at school mirrors the isolation from the host society that refugees and people seeking asylum are subjected to residentially. We then present an emergency response to school closures: A digital homework mentorship program designed to mitigate the heightened barriers to social interaction and access to education brought about by the pandemic. We explore the sociocultural theory underpinning the program, describe its methods, and offer a qualitative evaluation of the results. Finally, we discuss how the informal education intervention helps fill gaps in the system, offering an approach that can be used going forward to promote learning, social-emotional development, and inclusion of young people with migration and refugee backgrounds.
Surface treatment-controlled solvothermal synthesis of highly active reduced 1D titania with heterojunctioned carbon allotrope
Authors: Badreldin Ahmed , Zakaria Yahya , Mansour Said , Abdel-Wahab Ahmed
Published: January 2021

One-dimensional (1D) nanowire black titania heterojunctioned with multi-wall carbon nanotube (bTiO2 NW/MWCNT) structures were successfully synthesized via a facile single-step hydrothermal procedure, coupled with succeeding surface treatments and a solid-state physiochemical mode of reduction. Paramagnetic SiO2-coated Fe3O4 microspheres were fabricated and used as cores for the seeding and growth of the bTiO2 NW/MWCNT photocatalyst. The as-prepared photocatalysts were characterized via X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoemission spectroscopy, Fourier transform infrared spectroscopy, and UV-vis diffuse reflectance spectroscopy. The results of materials characterization confirmed formation of 1D bTiO2 NW structure with chemically bound MWCNT atop the reduced Ti3+ propagated lattice of the predominantly (101) exposed facets of anatase TiO2. Controlling the surface treatment process and NW growth time to maintain the anatase phase and stability of surface morphology upon reduction allowed for superior visible light-driven photoactivity. The visible light-driven photocatalytic degradation of 10 mg/L methylene orange was recorded at 97.4% in 20 min of 0.7 Sun intensity. The apparent reaction rate constant (k) of the as-prepared photocatalyst (0.1439 min−1) is ~ 18 times higher than that of pristine TiO2. Utilization of paramagnetic cores for in situ photocatalyst collection upon water treatment is highly recommended for newly developed materials. Further, performing surface treatment procedures of prepared titania-based photocatalysts has been proven to have a notable advantageous effect on photoactivity and is thus suggested for similar materials.
Analysis of gold nanoparticles in a hydrocarbon solvent by single particle-inductively coupled plasma mass spectrometry (spICP-MS) and TEM
Authors: Nelson Jenny , Saunders Aaron , Poirier Laura , Lopez-Linares Francisco
Published: January 2021

Single-particle inductively coupled plasma mass spectrometry (spICP-MS) is used increasingly to characterize element-containing nanoparticles (NPs) in various samples, providing data on the number, concentration, size of particles, as well as the dissolved element concentration. Because there are currently only three examples of spICP-MS analysis of NPs in hydrocarbons in the literature. There is a clear need for hydrocarbon-based NP reference materials (RMs), available for analysts to develop and validate new methods. Here, an analysis of spICP-MS data is presented for two custom-developed gold NP RMs in toluene. The particle size data obtained by spICP-MS is compared with the total particle diameter obtained by transmission electron microscopy (TEM) and shows the excellent agreement among both techniques.

Graphical abstract
Postoperative Outcomes after Index vs Interval Cholecystectomy for Perforated Cholecystitis
Authors: Krecko Laura K. , Gomez Tatiana Hoyos , Scarborough John E. , Jung Hee Soo
Published: January 2021

BACKGROUND:

Gallbladder perforation is a known morbid sequela of acute cholecystitis, yet evidence for its optimal management remains conflicting. This study compares outcomes in patients with perforated cholecystitis who underwent cholecystectomy at the time of index hospital admission with those in patients who underwent interval cholecystectomy.

STUDY DESIGN:

A retrospective analysis was conducted of 654 patients from the American College of Surgeons NSQIP database who underwent cholecystectomy for perforated cholecystitis (2006-2018). Primary outcomes were 30-day postoperative major and minor morbidity, 30-day mortality, and need for prolonged hospitalization. Patient and procedure characteristics and outcomes were compared using Mann-Whitney rank sum test for continuous variables and Pearson chi-square tests for categorical variables. A subset analysis was conducted of patients matched on propensity for undergoing interval cholecystectomy.

RESULTS:

The 30-day postoperative mortality rate of matched cohort patients undergoing index cholecystectomy was 7% vs 0% of patients undergoing interval cholecystectomy (p = 0.01). The 30-day minor morbidity rates were 2% for index and 8% for interval patients (p = 0.06), and the major morbidity rates were 33% for index and 14% for interval patients (p = 0.003). Of the index patients, 27% required prolonged hospitalization compared with 6% of interval patients (p < 0.001). Results showed similar trends in the unmatched analysis.

CONCLUSIONS:

Patients who underwent index cholecystectomy had significantly longer postoperative hospitalizations and higher 30-day postoperative major morbidity and mortality. There were no differences in 30-day minor morbidity. Selected patients with perforated cholecystitis can benefit from operative management on an interval, rather than urgent, basis.