bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of the effects of diabetes mellitus and metformin usage on serum vitamin B12 levels in cobalamin deficient subjects
Authors: AVCI Duygu Nurdan , ERSOY Canan
Published: April 2020

Abstract: Introduction:Although there are studies evaluating vitamin B12 levels in different patient groups, there is none encountered in Turkish adult patients with or without DM reported in the English literature.The aim of the study was to evaluate the possible additional effects of diabetes and metformin usage on serum levels of vitamin B12 in cobalamin deficient Turkish adult patients. Material and Methods:Medical records of subjects ≥18 years of age, having a vitamin B12 level <180 pg/mL were screened, consecutive 98 subjects were included in the study. Results:Among a total of 75 female and 23 male subjects with a mean age of 51.3±15.9 years and vitamin B12 level of 139.3±29.2 pg/mL, 34 had the diagnosis of type 2 diabetes mellitus and 64 had no diabetes diagnosis. Mean ages were 59.0±10.8 years for diabetics and 47.2±16.8 years for nondiabetics. Vitamin B12 levels were found to be insignificantly low in people with the diagnosis of diabetes compared to without diabetes (131.2±30.6 and 143.5±27.7 pg/mL, respectively, p=0.05). Vitamin B12 levels had no correlation with diabetes duration, presence of complications, metformin usage duration. Conclusions:In conclusion, our results demonstrated that people with diabetes had lower levels of vitamin B12 compared to nondiabetics but this fact could not solely be explained by the duration of disease, accompanying complications, metformin treatment duration. All patients with or without the diagnosis of diabetes should be encouraged for sufficient vitamin B12 intake and all possible factors that lead to deficiency should be eliminated.
A Case of Pituitary Insufficiency in a Patient Presenting with Hyponatremia: Might Be Slow-Progressing Lymphocytic Hypophysitis as a Possible Cause of Empty Sella?
Authors: ELBÜKEN Gülşah , BAYDAR Ece , KARA Sonat Pınar
Published: April 2020

Case: A 75-year-old female patient presented with complaints of nausea, weakness, fatigue and generalized pain all over her body. Her medical history included essential hypertension, type 2 Diabetes Mellitus, coronary artery disease and hypothyroidism.
She was hospitalized due to detecting a serum sodium (Na) concentration of 123 mmol/L. Although her diuretic medications were discontinued and fluid replacement with parenteral hypertonic saline infusion was instituted for approximately 6 days, Na level did not return to normal. Secondary hypothyroidism was considered due to laboratory test results showing low fT4 level and markedly suppressed TSH value. Since further laboratory workup showed that TSH, ACTH, PRL, GH and gonadotropins were also low, the diagnosis was confirmed as “panhypopituitarism”. Her obstetric history was not suggestive of Sheehan’s Syndrome and she did not have a history of head injury or cerebrovascular disease. She was started on parenteral 100 mg hydrocortisone and hormonal replacement therapy with oral levothyroxine. The clinical picture of the patient improved dramatically with resolution of hyponatremia.
Results and Discussion: Lymphocytic hypophysitis is an autoimmune disorder of the pituitary gland and it mostly affects middle-aged women. The fact that our patient was the age of 75 without having any clinical symptoms, since she had “panhypopituitarism” and a “partially empty sella” appearance in her pituitary MRI scans, “lymphocytic hypophysitis” was considered as the probably cause of pituitary insufficiency even if her age was older than the typical age of patients affected by the condition.
Conclusion: It suggests that slow-progressing primary hypophysitis (probably lymphocytic hypophysitis) can lead to pituitary insufficiency at a later age.
Introduction and contemporary condition of helicopter emergency medical services in Korea
Authors: Cho Jin-Seong , Yang Hyuk Jun
Published: April 2020

As most medical facilities in Korea have been concentrated in large cities, the need to improve emergency medical services in islands and mountainous areas has emerged. Consequently, the Ministry of Health and Welfare and local governments have introduced emergency medical helicopters (known as helicopter ambulances or air ambulances) with doctors in medically vulnerable areas. Having been introduced in two regions in 2011, air ambulances are operational in seven regions as of the end of 2019. The flight time is from sunrise to sunset, except in Gyeonggi province, which is open all day. Although the criteria for transport vary depending on whether an ambulance is available for operation, it is basically intended for emergency critical diseases, such as severe trauma, stroke, and acute myocardial infarction. From September 23, 2011 to December 31, 2018, a total of 10,367 transfer requests were received, which included 534 (5.2%) interruptions, 2,657 (25.6%) rejects, and 7,176 (69.2%) transfers. A total of 7,209 patients were transferred during this period, which included 1,693 (23.5%) patients of severe trauma, 1,149 (15.9%) patients of stroke, 802 (11.1%) patients of acute myocardial infarction, and 3,565 (49.5%) patients suffering from other emergency diseases. Some economic research on air ambulances in Korea has been reported to be cost-effective, but additional research should be performed. In the future, it is necessary to widen the area of operation of air ambulances and find alternative means of transporting patients during unfavorable conditions such as night or bad weather.
Future development of helicopter emergency medical services in Korea
Authors: Yeom Seok Ran , Kim Oh Hyun , Lee Kang Hyun
Published: April 2020

This paper discusses the future development of air ambulance operations in Korea. Helicopter emergency medical services are a useful means of transporting critically ill patients to the right hospital, at the right time. It is an important element of the emergency medical system to treat acute diseases at the scene, or in transit. For more efficient operations of the emergency medical helicopters (air ambulances or the so-called ‘Doctor Helgi’ in Korea), various challenges are faced. These include, the expansion of air ambulance bases, proper placement of rendezvous points (landing point), increase of field transport requests, and the operation of night missions. First, it is necessary to reduce the disparity in the benefits of emergency medical care for critically ill patients through the expansion of helicopter bases. Second, through the advancement of joint operations of the pan-ministerial emergency medical helicopters, the time from dispatch to helicopter take-off should be minimized, and a quality improvement program for air transportation should be carried out. Third, it is necessary to increase the number of insufficient rendezvous points and ensure the safety of the helicopters during takeoff and landing, to activate field transportation. Finally, the safety of patients and medical staff should be secured through the systematic preparation of the air transport system for future night missions. To solve these tasks, an appropriate legal system for helicopter emergency medical service is required. Based on the improved system, it is expected that everyone will enjoy equal rights for health, regardless of the regions.
Symptom-based selection of antidepressants
Authors: Park Seon-Cheol
Published: April 2020

Most evidence-based pharmacological guidelines recommend selective serotonin reuptake inhibitors, serotoninnorepinephrine reuptake inhibitors, norepinephrine-dopamine reuptake inhibitors or norepinephrine and specific serotonin antidepressants as the first-line treatment for major depression. Since the clinical factors associated with treating patients with depression are relatively complex, it can be challenging to apply the recommendations of evidence-based medicine verbatim. Furthermore, the diagnostic criteria of major depressive disorders, which are defined in a polythetic and operational manner, inevitably result in their heterogeneity. Studies have inferred that depressive syndrome may be connected with “family resemblance” rather than being shared with a neurobiological essence. Therefore, the symptom-based selection of antidepressants can be supported by a network analysis that provides a novel perspective on the symptom structure of major depression. The symptom-based treatment algorithm suggests treatment options that can be applied to the symptoms that are included in and excluded from the diagnosis criteria of major depressive disorder. The symptom-based selection of antidepressants and other psychotropic agents involves matching the deconstructed symptoms of depression to the specific neuroanatomical regions and neurotransmitters. This ensures timely and optimized treatment options for patients with depression.
Research for improvement of the national evaluation program for emergency medical center in Korea
Authors: Han Kap Su , Kim Won Young , Kim Su Jin , Jeong Jinwoo , Kang Hyunggoo , Lee Chulung , Lee Sung Woo
Published: April 2020

In Korea, the national evaluation program for emergency medical centers (EMCs) was introduced in 2003. EMCs in Korea have three levels of emergency centers including regional emergency centers, local emergency centers, and local emergency rooms. The evaluation system assesses the performance of EMCs at all three levels. The role of both regional emergency centers and local emergency centers administer the final treatment for severe emergency patients, although the definition of severe emergency patients is unclear. These factors may aggravate crowding at the emergency department. The national evaluation system aims to reduce the length of stay in the emergency department. However, reduction of the length of stay at emergency department may cause a conflict with the administration of final treatment for critically ill emergency patients owing to a lack of in-hospital beds. Crowding of the emergency department is not a problem of EMCs but that of the health system. In 2019, the Korean Society of Emergency Medicine performed a study to improve the national evaluation program for EMC and the performance of EMC. Here, we have summarized the results.
Cretaceous oceanic anoxic events prolonged by phosphorus cycle feedbacks
Authors: Beil Sebastian , Kuhnt Wolfgang , Holbourn Ann , Scholz Florian , Oxmann Julian , Wallmann Klaus , Lorenzen Janne , Aquit Mohamed , Chellai El Hassane
Published: April 2020

Abstract. Oceanic anoxic events (OAEs) document major perturbations
of the global carbon cycle with repercussions for the Earth's climate and
ocean circulation that are relevant to understanding future climate trends.
Here, we compare the onset and development of Cretaceous OAE1a and OAE2 in
two drill cores with unusually high sedimentation rates from the Vocontian
Basin (southern France) and Tarfaya Basin (southern Morocco). OAE1a and OAE2
exhibit remarkable similarities in the evolution of their carbon isotope
(δ13C) records, with long-lasting negative excursions preceding
the onset of the main positive excursions, supporting the view that both
OAEs were triggered by massive emissions of volcanic CO2 into the
atmosphere. However, there are substantial differences, notably in the
durations of individual phases within the δ13C positive
excursions of both OAEs. Based on analysis of cyclic sediment variations, we
estimate the duration of individual phases within OAE1a and OAE2. We
identify (1) a precursor phase (negative excursion) lasting ∼430 kyr for OAE1a and ∼130 kyr for OAE2, (2) an onset phase
of ∼390 and ∼70 kyr, (3) a peak phase of
∼600 and ∼90 kyr, (4) a plateau phase of
∼1340 and ∼200 kyr, and (5) a recovery phase of
∼380 and ∼440 kyr. The total duration of the
positive δ13C excursion is estimated at 2700 kyr for OAE1a and
790 kyr for OAE2, and that of the main carbon accumulation phase is estimated at 980 and
180 kyr. The long-lasting peak, plateau and recovery phases imply
fundamental changes in global nutrient cycles either (1) by submarine
basalt–seawater interactions, (2) through excess nutrient inputs to the
oceans by increasing continental weathering and river discharge, or (3) through nutrient recycling from the marine sediment reservoir. We
investigated the role of phosphorus in the development of carbon
accumulation by analysing phosphorus speciation across OAE2 and the
mid-Cenomanian Event (MCE) in the Tarfaya Basin. The ratios of organic
carbon and total nitrogen to reactive phosphorus (Corg∕Preact and
Ntotal∕Preact) prior to OAE2 and the MCE hover close to or below
the Redfield ratio characteristic of marine organic matter. Decreases in
reactive phosphorus resulting in Corg∕Preact and
Ntotal∕Preact above the Redfield ratio during the later phase of
OAE2 and the MCE indicate leakage from the sedimentary column into the water
column under the influence of intensified and expanded oxygen minimum zones.
These results suggest that a positive feedback loop, rooted in the benthic
phosphorus cycle, contributed to increased marine productivity and carbon
burial over an extended period of time during OAEs.
Monitoring of the reconstruction process in a high mountainous area affected by a major earthquake and subsequent hazards
Authors: Tang Chenxiao , Liu Xinlei , Cai Yinghua , Van Westen Cees , Yang Yu , Tang Hai , Yang Chengzhang , Tang Chuan
Published: April 2020

Abstract. Recovering from major earthquakes is a challenge, especially in mountainous environments where postearthquake hazards may cause substantial impacts for prolonged periods of time. Although such impacts were reported in the 1923 Great Kantō earthquake and the 1999 Chi-Chi earthquake, careless reconstruction in hazard-prone areas and consequently huge losses were
witnessed following the 2008 Wenchuan earthquake in the Sichuan province of
China, as several reconstructed settlements were severely damaged by mass
movements and floods. In order to summarize experiences and identify
problems in the reconstruction planning, a monitoring of one of the
settlements, the town of Longchi, was carried out by image interpretation and field investigation. Seven inventories containing buildings, farmlands, roads and mitigation measures were made to study the dynamics of elements at risk and exposure over a period of 11 years. It was found that the total economic value of the newly reconstructed buildings was several times more than in the preearthquake situation in 2007, because of enormous governmental investment. Postseismic hazards were not sufficiently taken into consideration in the recovery planning before the catastrophic debris flow disaster in 2010. As a result, the direct economic loss from postseismic disasters was slightly more than the loss caused by the Wenchuan earthquake itself. The society showed an impact-adapt pattern, experiencing losses from disasters and then gaining resistance by abandoning buildings in hazard-prone areas and installing mitigation measures. The locations potentially exposed to postearthquake hazards were summarized, and a possible timetable for reconstruction was proposed. Problems might be encountered in hazard assessment, and possible solutions were discussed.
A comparison of anamorphs of some Pachyphlodes species and the type of Chromelosporium: are they congeneric?
Authors: Hennebert Grégoire L. , Decock Cony
Published: April 2020

There is a question of whether or not the name Chromelosporium competes with the name Pachyphlodes given that both genera exhibit similar conidiogenesis. We address here the question through a comparative study of their anamorphs. The type specimen of C. ochraceum
(generic type of Chromelosporium), has been studied and compared to newly collected specimens of two Pachyphlodes species, P. nemoralis and P. citrina (whose identity was confirmed through comparison of ITS DNA sequences) and an unidentified species from the
Pachyphlodes–Plicariella lineage. Comparison of the morphology of the Pachyphlodes–Plicariella lineage anamorphs with Chromelosporium ochraceum reveals discriminating characters that may support a generic distinction.
Reviewer Acknowledgements for International Journal of Statistics and Probability, Vol. 9, No. 3
Authors: Smith Wendy
Published: April 2020

Reviewer Acknowledgements for International Journal of Statistics and Probability, Vol. 9, No. 3, 2020
Mentoring Secondary Novice Teachers to Develop Academic Language of English Language Learners
Authors: O'Hara Susan , Bookmyer Joanne , Pritchard Robert , Martin Robin
Published: April 2020

This exploratory, qualitative study examines the foundational knowledge and instructional methods needed for academic language teaching of English language learners (ELLs). It also examines how mentoring practices can build secondary content-based novice teachers’ instructional capacity in this area. The study uses synthesized data from two independent studies to contextualize findings on essential instructional practices within the process of mentoring new teachers. Three themes emerged: novices need the foundational, theoretical and practical knowledge underlying essential practices for academic language development; essential practices must be articulated in detail for enactment by teachers; and balancing explicit and immersive academic language instruction is a major paradigm shift for novices. Implications for mentor and teacher professional development are discussed, as mentors are key to supporting the uptake of dynamic instructional methods needed to enact essential practices. While mentoring is a common strategy for supporting new teachers, few models exist for how mentors can support new teachers with building the academic language development of ELLs. Further, few studies examine mentoring exchanges that can promote teachers’ understanding and practices to support ELL students’ academic language development. Limitations of the study include sample size and use of varied respondent data sets.
Gymkhana Olímpica
Authors: Aguilera Díaz Juan Manuel
Published: April 2020

Su título hace referencia a las diversas gymkhanas matemáticas que organizamos en Alcalá la Real de forma anual y que nos dan un bagaje y tranquilidad organizativa en este tipo de pruebas y por supuesto, el término también se refiere a la prueba por equipos de la XXX Olimpiada Matemática para 2º ESO que el departamento de matemáticas del IES Alfonso XI organizó en Junio de 2019. A ambos aspectos haremos referencia en este texto escrito.
El vídeo post-evaluador como actividad didáctica personal
Authors: Delgado Pineda Miguel
Published: April 2020

En este trabajo se presenta una forma de afrontar tener que explicar la forma de resolver cada uno de los problemas de las Pruebas Presenciales o exámenes que realiza un estudiante de la UNED. Esta forma es mediante vídeo digital, a los cuales se accede bajo demanda con lo cual el estudiante puede optar por ver cada uno de los vídeos de forma independiente sin tener que dedicarle nada más que unos pocos minutos, en general menos de 5 minutos. Una actuación docente dentro el márco didáctico que posee interes para el estudiante es constatar cómo se contestaban o resolvian las cuestiones y problemas a las que se hubiese enfrentado en una prueba o examen. En una universidad no presencial como UNED no podemos seguir la línea que entendemos acertada, por parte de los profesores presencial, consistente en dedicar una clase para explicar cada uno de los problemas que propuso en la prueba. Esto decisión estratágica resulta importante incluso antes de que el profesor hubiera evaluado la prueba, pues tiene que actuarse cuando el estudiante tiene fresco en la memoria todo aquello que escribió. De alguna forma estos vídeos intentan cubrir la distancia en la UNED entre el profesor y estudiante al menor en el momento postevaluación y emular esa trasmisión directa del profesor presencial. Estos vídeos no están diseñados para enseñar estratégias de resolución como la mayoría de los vídeos disponibles por la red, aunque puedieran ser utilizados de esta forma. Estos videos intentan que el estudiante aprenda la forma en la cual el profesor resuelve el problema al que el estudiante se enfrentó en un exámen. Además, son vídeos que el profesor facilita para que el estudiante se fije en aquello en lo que él se fina, y los resultados teóricos que utiliza. Con estos vídeos el profesor tiene la esperanza de que el estudiante adquiera una mayor competencia de exposición de sus conocimientos.
A perceção de divertimento em jovens, adultos e idosos: um estudo comparativo
Authors: Rodrigues Filipe , Cid Luís , Forte Pedro , Gonçalves Carlos , Machado Sérgio , Neiva Henrique , Teixeira Diogo , Monteiro Diogo
Published: April 2020

Objetivo: Este estudo teve como objetivo de analisar a perceção de divertimento em diferentes grupos etários, nomeadamente entre jovens, adultos e idosos. Acrescido, analisamos a validade preditiva do divertimento como preditor da intenção de continuar na prática de atividade física, e como consequência da motivação intrínseca. Métodos: Participaram ao todo 425 indivíduos portugueses praticantes de atividade física regular. Todos os participantes preencheram o questionário online tendo em consideração todas as variáveis em análise. Resultados: Os resultados da análise do modelo de medida evidenciam que este apresentou ser invariante entre as faixas etárias. Tal como teoricamente proposto, o divertimento demonstrou ser um preditor significativo da intenção e uma consequência de maiores níveis de motivação intrínseca. Conclusão: A escala utilizada na medição da perceção de divertimento demonstra ser um instrumento fiável, ao qual é equivalente tanto para jovens, como para adultos e idosos. O divertimento deve ser medido e considerado como variável chave na análise dos níveis de atividade física reportados por indivíduos em diferentes faixas etárias.
EDUCOMUNICAÇÃO COMO SUBSÍDIO AO RESGATE CULTURAL DA POPULAÇÃO DE SÃO ROQUE DE MINAS – MG
Authors: Zampieron Sônia Lúcia Modesto , Ricardino Luciana Grilo
Published: April 2020

O modelo de desenvolvimento atual vem exaurindo os recursos do planeta e comprometendo a vida humana e a do meio. A Educomunicação chega como uma ferramenta capaz de traduzir as relações entre homens e natureza, na medida em que resgata a cultura e a cidadania, através de mecanismos que promovem interação e expressão da comunidade. Neste trabalho experimentou-se a Educomunicação, por meio de oficinas de jornalismo e de produção audiovisual, envolvendo alunos e a população local. Disso resultou a produção de mini-documentários em audiovisual e criação do programa experimental de rádio-escola: “Bom dia, Canastra!”, um radiojornal que envolveu toda comunidade escolar e também atores da cidade, revelando sua eficiência no resgate cultural local, ao abrir espaço de divulgação de temas que enaltecem a cultura dos moradores locais
Policy Influence Citarum Harum against Aquaculturist on Floating Cage in Saguling Reservoir, West Bandung District
Authors: Ahmad Fadilah , Rizal Achmad , Dewanti Lantun P. , Handaka Asep Agus
Published: April 2020

This research aims to analyze the policy about Citarum Harum and analyze social economy condition fisheries resource from freshwater on floating cage Saguling Reservoir, West Bandung District. This research was conducted in Saguling Reservoir, West Bandung District, starting in August until November 2019. The method of data collection was carried out by survey methods, the technique of taking respondents using a purposive sampling technique. This research data consists of two types of data, namely primary data and secondary data. Analysis of the data used in this research includes the Likert Scale and business analysis. The result of the analysis policy influence use Likert Scale has an average index value at 8562%. This average index means the influence of policy citarum harum is considered very well by related stakeholders. Analysis of social-economic conditions The aquaculturist has good economic potential. Seen from the result of income and business analysis on each cultivator showing value Rp.17.125.000/3month and RCR value as big as 1,922.
Effect of Drying Temperature on the Quality of Dry Surimi Powder from Pangasius
Authors: Sarkar P. , Chowdhury S. , Nath S. , Murmu P. , Rahman F. H.
Published: April 2020

Demands for fish protein including dried fish protein to develop functional food are gradually growing in the world. Surimi, the concentrated myofibrillar protein extracted from fish flesh by washing minced meat, separated from bones, skin, and guts with added cryoprotectants such as sugar or alcohol (most commonly used cryoprotectant in the surimi industry is 1:1 mixture of sucrose and sorbitol at a concentration of 8%), finally stored in frozen condition in block form, is used as a raw material for preparation of number of value-added products. The dried form of surimi can be prepared from frozen surimi blocks by adopting different drying technologies and it offers many advantages such as ease of handling, lower distribution costs and more convenient storage. The present work is aimed to study the effect of drying temperature on the quality of dry surimi powder, prepared from Pangasius meat. A significantly higher (p<0.05) value of ash (1.83±0.47%) was recorded in surimi powder dried at 60°C than at 50°C and 70°C. The moisture content significantly (p<0.05) reduced at 60° (9.05±0.22%) and 70°C (9.55±0.51%) as compared to 50°C. The quality parameters such as TVB-N, PV, pH and TPC were all found to be well within the recommended level of acceptability except for the surimi powder dried at 50°C, wherein the TVBN (36.24±1.26 mg/100 g) crossed the limit of acceptability. Drying temperature was found to affect the colour of the surimi powder with the optimum acceptable colour score achieved at 60°C (6.38±0.52). At higher temperature of 70°C darkening was observed with consequent decrease in the colour scores (5.75±0.46). Therefore, the optimal temperature for drying of Pangasius surimi into its powdered form was achieved during its exposure at temperature of 60°C.
Differential Pulse Polarography Method for the Determination of Trace Fe, Ni, Pb, Zn, Se and Cu in Black Tea Leaves
Authors: Kalayc Sukru , Somer Guler
Published: April 2020

In this work a new and simple polarographic method has been established for the determination of trace elements present in tea. After digestion with acids, tea samples were analyzed using various electrolytes such as acetate and ammonia at different pH values in the presence or absence of EDTA. Thus, it was possible tochoosethe best medium for the determination of6 trace elements in one tea sample. Polarographic peaks of copper and iron could be separated in HAc at about pH =7 in the presence of EDTA and their quantities were determined. Ni and Zn peaks could be separated and determined in ammonia buffer at about pH= 10. Lead could be determined at pH= 2HAc electrolyte. Selenite, was determined from its hydrogen catalytic peak in KCl, pH= 2 medium in the presence of Mo (VI). The LOD was found as 2.4x10-7 for instead of (S/N=3).The trace element ranges in black tea were found as, Fe 35 μg/g, Cu 45 μg/g, Ni 19 μg/g, Zn  22 μg/g, Pb 28 μg/g and Se 77  μg/g.
Health-Related Quality of Life among University Healthcare Academics
Authors: Iqbal Muhammad Shahid , Al-Saikhan Fahad I. , Iqbal Muhammad Zahid
Published: April 2020

Introduction: Having a good health-related quality of life (HRQoL) is important to ensure good job performance. However, it is subjective and it cannot be measured easily. This study aimed  to evaluate HRQoL among universityhealthcare academics in public andprivate  universities.

Method: In this study,a stratified random sampling approach was employed. The strata were created based on departments in the universities. A random sample from each stratum was taken in a number proportional to the stratum's size when compared to the overall target population. A validated questionnaire comprising two sections was administered online to collect the data. Descriptive and inferential statistical analysis (Mann-Whitney U test and Kruskal Wallis H test) were applied using SPSS version 22.

Results: Out of all the total 130 respondents, 57 (43.8%) were from a private university and the other 73 (56.2%) were from a public university. There were 61 (46.9%) male respondents and 69 (53.1%) female respondents. HRQoL according to the studied domains of the DUKE health profile was associated with various demographic and socioeconomic variables such as type of institution, department/faculty, age, gender, number of children, and years of experience.

Conclusion:The demographic and socioeconomic variables were strongly associated with the HRQoL among university healthcare academics.
A Novel Al‐Rich/Ti–6Al–4V Layered Composite with Superior Wear and Electrochemical Behavior
Authors: Liu Shaopeng , Zhang Zhong , Tang Yongbo , Chen Yungui
Published: April 2020

By adding a certain amount of Al to the surface of Ti–6Al–4V (TC4) alloy, a novel layered composite composed of TC4 alloy matrix and Al‐rich alloy is designed and successfully fabricated by a blended elemental powder metallurgy (BE PM) method. The results demonstrated that after the addition of 1 wt% Al, the layered composite exhibits superior wear and electrochemical behavior over powder metallurgy Ti–6Al–4V (PM TC4) alloy, which indicates that a wear‐resistant and corrosion‐resistant layer can be in situ synthesized on the sample surface. Moreover, the volume fraction of α phase, the thickness of α colonies, porosity, Rockwell hardness, and wear resistance of the layered composites increase significantly with Al addition, resulting in the decrease in area, width, and depth of wear tracks, and the reduction of average friction coefficients (COFs). Furthermore, with the addition of Al, the galvanic effect at the interface of α/β phase reduces, whereas the porosity of the layered composites, the chemical activity, and the corrosion rate of α phase increase significantly. Therefore, the corrosion resistance of the layered composites increases first and then decreases with Al addition, and the optimum value can be achieved when the added amount of Al is 1 wt%.
A Conditionally Releasable “Do not Eat Me” CD47 Signal Facilitates Microglia‐Targeted Drug Delivery for the Treatment of Alzheimer's Disease
Authors: Zhang Lun , Liu Xiao‐ge , Liu Dong‐qun , Yu Xiao‐lin , Zhang Ling‐xiao , Zhu Jie , Lu Shuai , Liu Rui‐tian
Published: April 2020

Efficient brain drug delivery has been a challenge in the treatment of Alzheimer's disease (AD) and other brain disorders as blood‐brain barrier (BBB) impedes most drugs to reach brain. To overcome this obstacle, a novel poly(lactic‐co‐glycolic acid) (PLGA) nanoparticle conjugated with CD47 extracellular domain via reactive oxygen species (ROS)‐responsive phenylborate ester bond exhibiting “do not eat me” signal and BBB penetrating peptide CRTIGPSVC (CRT) and microglia modulation agent Nec‐1s encapsulated in it is developed. The experimental results show that the designed nanoparticle efficiently increases its half‐life in blood circulation by preventing engulfment via phagocytes, and enhances its brain distribution by synergistic effect of CD47 and CRT. The high level of ROS in mouse brain releases CD47 from the nanoparticles and the resultant particles are effectively phagocytized by resident microglia. The engulfed Nec‐1s modulates pathological microglia to a beneficial state, which reduces Aβ burden, microgliosis and astrocytosis, decreases cytokine production and oxidative stress in the brains of AD mice, and finally attenuates cognition deficits and synapse loss. The results first demonstrate that the conditionally releasable “do not eat me” CD47 signal remarkably facilitates microglia‐targeted drug delivery and warrants further study to develop therapeutic agent for AD treatment.
Programmable Liquid Metal Microstructures for Multifunctional Soft Thermal Composites
Authors: Haque A. B. M. Tahidul , Tutika Ravi , Byrum Rachael L. , Bartlett Michael D.
Published: April 2020

Soft, elastically deformable composites can enable new generations of multifunctional materials for electronics, robotics, and reconfigurable structures. Liquid metal (LM) droplets dispersed in elastomer matrices represent an emerging material architecture that has shown unique combinations of soft mechanical response with exceptional electrical and thermal functionalities. These properties are strongly dependent on the material composition and microstructure. However, approaches to control LM microdroplet morphology to program mechanical and functional properties are lacking. Here, this limitation is overcome by thermo‐mechanically shaping LM droplets in soft composites to create programmable microstructures in stress‐free materials. This enables LM loadings up to 70% by volume with prescribed particle aspect ratios and orientation, enabling control of microstructure throughout the bulk of the material. Through this microstructural control in soft composites, a material which simultaneously achieves a thermal conductivity as high as 13.0 W m−1 K−1 (>70 × increase over polymer matrix) with low modulus (<1.0 MPa) and high stretchability (>750% strain) is demonstrated in stress‐free conditions. Such properties are required in applications that demand extreme mechanical flexibility with high thermal conductivity, which is demonstrated in soft electronics, wearable robotics, and electronics integrated into 3D printed materials.
Stoichiometry Control for the Tuning of Grain Passivation and Domain Distribution in Green Quasi‐2D Metal Halide Perovskite Films and Light‐Emitting Diodes
Authors: Cheng Tai , Qin Chuanjiang , Watanabe Satoru , Matsushima Toshinori , Adachi Chihaya
Published: April 2020

Quasi‐2D metal halide perovskite films are promising for efficient light‐emitting diodes (LEDs), because of their efficient radiative recombination and suppressed trap‐assisted quenching compared with pure 3D perovskites. However, because of the multidomain polycrystalline nature of solution‐processed quasi‐2D perovskite films, the composition engineering always impacts the emitting properties with complicated mechanisms. Here, defect passivation and domain distribution of quasi‐2D perovskite films prepared with various precursor compositions are systematically studied. As a result, in perovskite films prepared from stoichiometric quasi‐2D precursor compositions, large organic ammonium cations function well as passivators. In comparison, precursor compositions of simply adding large organic halide salt into a 3D perovskite precursor ensure not only the defect passivation but also the effective formation of quasi‐2D perovskite domains, avoiding unfavorable appearance of low‐order domains. Quasi‐2D perovskite films fabricated with a well‐designed precursor composition achieve a high photoluminescence quantum yield of 95.3% and an external quantum efficiency of 14.7% in LEDs.
Synergy of Ion Doping and Spiral Array Architecture on Ti2Nb10O29: A New Way to Achieve High‐Power Electrodes
Authors: Deng Shengjue , Zhu He , Liu Bo , Yang Liang , Wang Xiuli , Shen Shenghui , Zhang Yan , Wang Jiaao , Ai Changzhi , Ren Yang , Liu Qi , Lin Shiwei , Lu Yangfan , Pan Guoxiang , Wu Jianbo , Xia Xinhui , Tu Jiangping
Published: April 2020

Ameliorating electronic/ionic transport and structural stability of electrode materials is important to the development of power‐intensive lithium ion batteries. Despite its great potential as a high‐power anode, titanium niobium oxide (Ti2Nb10O29, TNO) still underperforms due to its unsatisfactory electronic/ionic conductivity. In this work, a powerful synergistic strategy by combining ion doping and spiral array architecture to boost high‐rate performance of TNO is reported. Cr3+ doped TNO nanoparticles (Cr‐TNO) of 5–10 nm intimately grow on a conductive vertical graphene@TiC‐C (VGTC) skeleton, forming novel Cr‐TNO@VGTC spiral arrays. The unique spiral growth of TNO is achieved due to the confinement effect of VGTC skeleton. Meanwhile, a more open TNO crystal structure with faster ion transfer paths and enhanced structural stability is realized by Cr3+ doping, demonstrated via density functional theory calculation and in situ synchrotron X‐ray diffraction technique. Benefiting from the superior conductive network, enhanced intrinsic electronic/ionic conductivity of Cr‐TNO and reinforced structural stability, the Cr‐TNO@VTC arrays show prominent high‐power performance with a large capacity of 220 mAh g−1 at 40 C (power density of ≈11 kW kg−1) and superior durability (91% retention after 500 cycles). This work provides a new path for the construction of widespread high‐power electrodes for fast energy storage.
Multifunctional Pacemaker Lead for Cardiac Energy Harvesting and Pressure Sensing
Authors: Dong Lin , Closson Andrew B. , Jin Congran , Nie Yuan , Cabe Andrew , Escobedo Danny , Huang Shicheng , Trase Ian , Xu Zhe , Chen Zi , Feldman Marc D. , Zhang John X. J.
Published: April 2020

Biomedical self‐sustainable energy generation represents a new frontier of power solution for implantable biomedical devices (IMDs), such as cardiac pacemakers. However, almost all reported cardiac energy harvesting designs have not yet reached the stage of clinical translation. A major bottleneck has been the need of additional surgeries for the placements of these devices. Here, integrated piezoelectric‐based energy harvesting and sensing designs are reported, which can be seamlessly incorporated into existing IMDs for ease of clinical translation. In vitro experiments validate the energy harvesting process by simulating the bending and twisting motion during heart cycle. Clinical translation is demonstrated in four porcine hearts in vivo under various conditions. Energy harvesting strategy utilizes pacemaker leads as a means of reducing the reliance on batteries and demonstrates the charging ability for extending the lifetime of a pacemaker battery by 20%, which provides a promising self‐sustainable energy solution for IMDs. The additional self‐powered blood pressure sensing is discussed, and the reported results demonstrate the potential in alerting arrhythmias by monitoring the right ventricular pressure variations. This combined cardiac energy harvesting and blood pressure sensing strategy provides a multifunctional, transformative while practical power and diagnosis solution for cardiac pacemakers and next generation of IMDs.
A New Microengineered Platform for 4D Tracking of Single Cells in a Stem‐Cell‐Based In Vitro Morphogenesis Model
Authors: Samal Pinak , Maurer Philipp , van Blitterswijk Clemens , Truckenmüller Roman , Giselbrecht Stefan
Published: April 2020

Recently developed stem‐cell‐based in vitro models of morphogenesis can help shed light on the mechanisms involved in embryonic patterning. These models are showcased using traditional cell culture platforms and materials, which allow limited control over the biological system and usually do not support high‐content imaging. In contrast, using advanced microengineered tools can help in microscale control, long‐term culture, and real‐time data acquisition from such biological models and aid in elucidating the underlying mechanisms. Here, a new culturing, manipulation and analysis platform is described to study in vitro morphogenesis using thin polycarbonate film‐based microdevices. A pipeline consisting of open‐source software to quantify 3D cell movement using 4D image acquisition is developed to analyze cell migration within the multicellular clusters. It is shown that the platform can be used to control and study morphogenesis in non‐adherent cultures of the P19C5 mouse stem cell line and mouse embryonic stem cells (mESCs) that show symmetry breaking and axial elongation events similar to early embryonic development. Using the new platform, it is found that localized cell proliferation and coordinated cell migration result in elongation morphogenesis of the P19C5 aggregates. Further, it is found that polarization and elongation of mESC aggregates are dependent on directed cell migration.
Defect‐Enhanced Polarization Switching in the Improper Ferroelectric LuFeO3
Authors: Barrozo Petrucio , Småbråten Didrik René , Tang Yun‐Long , Prasad Bhagwati , Saremi Sahar , Ozgur Rustem , Thakare Vishal , Steinhardt Rachel A. , Holtz Megan E. , Stoica Vladimir Alexandru , Martin Lane W. , Schlom Darrel G. , Selbach Sverre Magnus , Ramesh Ramamoorthy
Published: April 2020

Results of switching behavior of the improper ferroelectric LuFeO3 are presented. Using a model set of films prepared under controlled chemical and growth‐rate conditions, it is shown that defects can reduce the quasi‐static switching voltage by up to 40% in qualitative agreement with first‐principles calculations. Switching studies show that the coercive field has a stronger frequency dispersion for the improper ferroelectrics compared to a proper ferroelectric such as PbTiO3. It is concluded that the primary structural order parameter controls the switching dynamics of such improper ferroelectrics.
Controlling Preosteoblast Behavior through Manganese Vacancy‐Rich Birnessite with Enhanced Divalent Cation Modulation of Fibronectin–Integrin Interactions
Authors: Liu Shiwei , Li Kai , Hu Tao , Wu Xiaodong , Ao Haiyong , Xie Youtao , Zheng Xuebin
Published: April 2020

The osteoblast‐function associated integrin–ligand interactions are known to be dependent on divalent cations, but there is scarce information about the effect of Ca2+ and Mg2+ adsorption properties of an implant surface on integrin α5β1–fibronectin interactions and the subsequent osteoblast behavior. Cation adsorption properties are closely associated with the extent of structural defects in materials. Here, the birnessite‐type MnO2 coatings with different amounts of manganese vacancy (VMn) are prepared on Ti substrates via hydrothermal treatment (denoted as 1M100‐Ti, 5M100‐Ti, and 5M120‐Ti). The 5M120‐Ti surface with hierarchical flower‐like structure and the most stacked [MnO6] layers possess the highest VMn content, which is determined by the ratios of Mn3+/Mn4+ and K/Mn. The increased VMn content enhances the Ca2+ and Mg2+ adsorption properties of the birnessite coatings. When immersed in Ca2+/Mg2+ aqueous solution, the birnessite coatings significantly promote fibronectin adsorption and the exposure of cell‐binding domains on adsorbed fibronectin with 5M120‐Ti showing the greatest enhancement. Accordingly, the 5M120‐Ti surface provides more α5β1‐integrin‐specific instructions to MC3T3‐E1 preosteoblasts capable of enhancing spreading and osteoblastic differentiation compared to two other samples. This study may provide a prospective approach of modulation of integrin–ligand interactions for controlling cell behavior by adjusting metal vacancies in metal oxides coatings.
Self‐Cleaned Photonic‐Enhanced Solar Cells with Nanostructured Parylene‐C
Authors: Centeno Pedro , Alexandre Miguel F. , Chapa Manuel , Pinto Joana V. , Deuermeier Jonas , Mateus Tiago , Fortunato Elvira , Martins Rodrigo , Águas Hugo , Mendes Manuel J.
Published: April 2020

Photonic front‐coatings with self‐cleaning properties are presented as means to enhance the efficiency and outdoor performance of thin‐film solar cells, via optical enhancement while simultaneously minimizing soiling‐related losses. This is achieved by structuring parylene‐C transparent encapsulants using a low‐cost and highly‐scalable colloidal‐lithography methodology. As a result, superhydrophobic surfaces with broadband light‐trapping properties are developed. The optimized parylene coatings show remarkably high water contact angles of up to 165.6° and extremely low adhesion, allowing effective surface self‐cleaning. The controlled nano/micro‐structuring of the surface features also generates strong anti‐reflection and light scattering effects, corroborated by numeric electromagnetic modeling, which lead to pronounced photocurrent enhancement along the UV–vis–IR range. The impact of these photonic‐structured encapsulants is demonstrated on nanocrystalline silicon solar cells, that show short‐circuit current density gains of up to 23.6%, relative to planar reference cells. Furthermore, the improvement of the devices' angular response enables an enhancement of up to 35.2% in the average daily power generation.
A Review on Functionally Graded Materials and Structures via Additive Manufacturing: From Multi‐Scale Design to Versatile Functional Properties
Authors: Li Yan , Feng Zuying , Hao Liang , Huang Lijing , Xin Chenxing , Wang Yushen , Bilotti Emiliano , Essa Khamis , Zhang Han , Li Zheng , Yan Feifei , Peijs Ton
Published: April 2020

Functionally graded materials (FGMs) and functionally graded structures (FGSs) are special types of advanced composites with peculiar features and advantages. This article reviews the design criteria of functionally graded additive manufacturing (FGAM), which is capable of fabricating gradient components with versatile functional properties. Conventional geometrical‐based design concepts have limited potential for FGAM and multi‐scale design concepts (from geometrical patterning to microstructural design) are needed to develop gradient components with specific graded properties at different locations. FGMs and FGSs are of great interest to a larger range of industrial sectors and applications including aerospace, automotive, biomedical implants, optoelectronic devices, energy absorbing structures, geological models, and heat exchangers. This review presents an overview of various fabrication ideas and suggestions for future research in terms of design and creation of FGMs and FGSs, benefiting a wide variety of scientific fields.
Silicon‐Based Integrated Label‐Free Optofluidic Biosensors: Latest Advances and Roadmap
Authors: Wang Jiawei , Sanchez Mariana Medina , Yin Yin , Herzer Raffael , Ma Libo , Schmidt Oliver G.
Published: April 2020

By virtue of the well‐developed micro‐ and nanofabrication technologies and rapidly progressing surface functionalization strategies, silicon‐based devices have been widely recognized as a highly promising platform for the next‐generation lab‐on‐a‐chip bioanalytical systems with a great potential for point‐of‐care medical diagnostics. Herein, an overview of the latest advances in silicon‐based integrated optofluidic label‐free biosensing technologies relying on the efficient interactions between the evanescent light field at the functionalized surface and specifically bound analytes is presented. State‐of‐the‐art technologies demonstrating label‐free evanescent wave‐based biomarker detection mainly encompass three device configurations, including on‐chip waveguide‐based interferometers, microring resonators, and photonic‐crystal‐based cavities. Moreover, up‐to‐date strategies for elevating the sensitivities and also simplifying the sensing processes are discussed. Emerging laboratory prototypes with advanced integration and packaging schemes incorporating automatic microfluidic components or on‐chip optoelectronic devices lead to one significant step forward in real applications of decentralized diagnostics. Besides, particular attention is paid to currently commercialized label‐free optical bioanalytical models on the market. Finally, the prospects are elaborated with several research routes toward chip‐scale, low‐cost, highly sensitive, multi‐functional, and user‐friendly bioanalytical systems benefiting to global healthcare.