bluuebunny/crossref_metadata_2025 huggingface dataset:
Vapochromic Luminescent π‐Conjugated Systems with Reversible Coordination‐Number Control of Hypervalent Tin(IV)‐Fused Azobenzene Complexes
Authors: Gon Masayuki , Tanaka Kazuo , Chujo Yoshiki
Published: March 2021

The dynamic and reversible changes of coordination numbers between five and six in solution and solid states, based on hypervalent tin(IV)‐fused azobenzene (TAz) complexes, are reported. It was found that the TAz complexes showed deep‐red emission owing to the hypervalent bond composed of an electron‐donating three‐center four‐electron (3c–4e) bond and an electron‐accepting nitrogen–tin (N–Sn) coordination. Furthermore, hypsochromic shifts in optical spectra were observed in Lewis basic solvents because of alteration of the coordination number from five to six. In particular, vapochromic luminescence was induced by attachment of dimethyl sulfoxide (DMSO) vapor to the coordination point at the tin atom accompanied with a crystal–crystal phase transition. Additionally, the color‐change mechanism and degree of binding constants were well explained by theoretical calculation. To the best of our knowledge, this is the first example of vapochromic luminescence by using stable and variable coordination numbers of hypervalent bonds.
Ibuprofen enantiomers in premature neonates with patent ductus arteriosus: Preliminary data on an unexpected pharmacokinetic profile of S(+)‐ibuprofen
Authors: Padrini Roberto , Ancora Caterina , Nardo Daniel , De Rosa Giovanni , Salvadori Sabrina , Bonadies Luca , Frigo Anna Chiara , Lago Paola
Published: March 2021

S(+)‐ibuprofen (S‐IBU) and R(−)‐ibuprofen (R‐IBU) concentrations were measured in 16 neonates with patent ductus arteriosus during a cycle of therapy (three intravenous doses of 10–5–5 mg kg−1 at 24‐h intervals), at the end of the first infusion and 6, 24, 48, and 72 h later. Data were analyzed with a PK model that included enantiomer elimination rate constants and the R‐ to S‐IBU conversion rate constant. The T½ of S‐IBU in the newborn was much longer than in adults (41.8 vs. ≈2 h), whereas the T½ of R‐IBU appeared to be the same (2.3 h). The mean fraction of R‐ to S‐IBU conversion was much the same as in adults (0.41 vs. ≈0.60). S‐IBU concentrations measured 6 h after the first dose were higher than at the end of the infusion in 10 out of 16 cases, and in five cases, they remained higher even after 24 h. This behavior is unprecedented and may be attributable to a rapid R‐to‐S conversion overlapping with a slow S‐IBU elimination rate. In 13 of the 16 neonates, S‐IBU concentrations at 48 and/or 72 h were lower than expected, probably due to the rapid postnatal maturation of the newborn's liver metabolism.
Cancer diagnoses and survival rise as 65‐year‐olds become Medicare‐eligible
Authors: Patel Deven C. , He Hao , Berry Mark F. , Yang Chi‐Fu Jeffrey , Trope Winston L. , Wang Yoyo , Lui Natalie S. , Liou Douglas Z. , Backhus Leah M. , Shrager Joseph B.
Published: March 2021

Background

A Medicare effect has been described to account for increased health care utilization occurring at the age of 65 years. The existence of such an effect in cancer care, where it would be most likely to reduce mortality, has been unclear.

Methods

Patients aged 61 to 69 years who were diagnosed with lung, breast, colon, or prostate cancer from 2004 to 2016 were identified with the Surveillance, Epidemiology, and End Results database and were dichotomized on the basis of eligibility for Medicare (61‐64 vs 65‐69 years). With age‐over‐age (AoA) percent change calculations, trends in cancer diagnoses and staging were characterized. After matching, uninsured patients who were 61 to 64 years old (pre‐Medicare group) were compared with insured patients who were 65 to 69 years old (post‐Medicare group) with respect to cancer‐specific mortality.

Results

In all, 134,991 patients were identified with lung cancer, 175,558 were identified with breast cancer, 62,721 were identified with colon cancer, and 238,823 were identified with prostate cancer. The AoA growth in the number of cancer diagnoses was highest at the age of 65 years in comparison with all other ages within the decade for all 4 cancers (P < .01, P < .001, P < .01, and P < .001, respectively). In a comparison of diagnoses at the age of 65 years with those in the 61‐ to 64‐year‐old cohort, the greatest difference for all 4 cancers was seen in stage I. In matched analyses, the 5‐year cancer‐specific mortality was worse for lung (86.3% vs 78.5%; P < .001), breast (32.7% vs 11.0%; P < .001), colon (57.1% vs 35.6%; P < .001), and prostate cancer (16.9% vs 4.8%; P < .001) in the uninsured pre‐Medicare group than the insured post‐Medicare group.

Conclusions

The age threshold of 65 years for Medicare eligibility is associated with more cancer diagnoses (particularly stage I), and this results in lower long‐term cancer‐specific mortality for all cancers studied.

Lay Summary

Contributing to the current debate regarding Medicare for all, this study shows that the expansion of Medicare would improve cancer outcomes for the near elderly.
Li8Si8, Li10Si9, and Li12Si10: Assemblies of Lithium‐Silicon Aromatic Units
Authors: Manrique‐de‐la‐Cuba María Fernanda , Leyva‐Parra Luis , Inostroza Diego , Gomez Badhin , Vásquez‐Espinal Alejandro , Garza Jorge , Yañez Osvaldo , Tiznado William
Published: March 2021

We report the global minima structures of Li8Si8, Li10Si9, and Li12Si10 systems, in which silicon moieties maintain structural and chemical bonding characteristics similar to those of their building blocks: the aromatic clusters Td−Li4Si4 and C2v−Li6Si5. Electron counting rules, chemical bonding analysis, and magnetic response properties verify the silicon unit‘s aromaticity persistence. This study demonstrates the feasibility of assembling silicon‐based nanostructures from aromatics clusters as building blocks.
Reducing persecution is more effective for restoring large carnivores than restoring their prey
Authors: Bleyhl Benjamin , Ghoddousi Arash , Askerov Elshad , Bocedi Greta , Breitenmoser Urs , Manvelyan Karen , Palmer Stephen C. F. , Soofi Mahmood , Weinberg Paul , Zazanashvili Nugzar , Shmunk Valerii , Zurell Damaris , Kuemmerle Tobias
Published: March 2021

Large carnivores are currently disappearing from many world regions because of habitat loss, prey depletion, and persecution. Ensuring large carnivore persistence requires safeguarding and sometimes facilitating the expansion of their populations. Understanding which conservation strategies, such as reducing persecution or restoring prey, are most effective to help carnivores to reclaim their former ranges is therefore important. Here, we systematically explored such alternative strategies for the endangered Persian leopard (Panthera pardus saxicolor) in the Caucasus. We combined a rule‐based habitat suitability map and a spatially explicit leopard population model to identify potential leopard subpopulations (i.e., breeding patches), and to test the effect of different levels of persecution reduction and prey restoration on leopard population viability across the entire Caucasus ecoregion and northern Iran (about 737,000 km2). We identified substantial areas of potentially suitable leopard habitat (~120,000 km2), most of which is currently unoccupied. Our model revealed that leopards could potentially recolonize these patches and increase to a population of >1,000 individuals in 100 yr, but only in scenarios of medium to high persecution reduction and prey restoration. Overall, reducing persecution had a more pronounced effect on leopard metapopulation viability than prey restoration: Without conservation strategies to reduce persecution, leopards went extinct from the Caucasus in all scenarios tested. Our study highlights the importance of persecution reduction in small populations, which should hence be prioritized when resources for conservation are limited. We show how individual‐based, spatially explicit metapopulation models can help in quantifying the recolonization potential of large carnivores in unoccupied habitat, designing adequate conservation strategies to foster such recolonizations, and anticipating the long‐term prospects of carnivore populations under alternative scenarios. Our study also outlines how data scarcity, which is typical for threatened range‐expanding species, can be overcome with a rule‐based habitat map. For Persian leopards, our projections clearly suggest that there is a large potential for a viable metapopulation in the Caucasus, but only if major conservation actions are taken towards reducing persecution and restoring prey.
Full spectrum of clonal haematopoiesis‐driver mutations in chronic heart failure and their associations with mortality
Authors: Kiefer Katharina C. , Cremer Sebastian , Pardali Evangelia , Assmus Birgit , Abou‐El‐Ardat Khalil , Kirschbaum Klara , Dorsheimer Lena , Rasper Tina , Berkowitsch Alexander , Serve Hubert , Dimmeler Stefanie , Zeiher Andreas M. , Rieger Michael A.
Published: March 2021

Aims

Somatic mutations in haematopoietic stem cells can lead to the clonal expansion of mutated blood cells, known as clonal haematopoiesis (CH). Mutations in the most prevalent driver genes DNMT3A and TET2 with a variant allele frequency (VAF) ≥ 2% have been associated with atherosclerosis and chronic heart failure of ischemic origin (CHF). However, the effects of mutations in other driver genes for CH with low VAF (<2%) on CHF are still unknown.

Methods and results

Therefore, we analysed mononuclear bone marrow and blood cells from 399 CHF patients by deep error‐corrected targeted sequencing of 56 genes and associated mutations with the long‐term mortality in these patients (3.95 years median follow‐up). We detected 1113 mutations with a VAF ≥ 0.5% in 347 of 399 patients, and only 13% had no detectable CH. Despite a high prevalence of mutations in the most frequently mutated genes DNMT3A (165 patients) and TET2 (107 patients), mutations in CBL, CEBPA, EZH2, GNB1, PHF6, SMC1A, and SRSF2 were associated with increased death compared with the average death rate of all patients. To avoid confounding effects, we excluded patients with DNMT3A‐related, TET2‐related, and other clonal haematopoiesis of indeterminate potential (CHIP)‐related mutations with a VAF ≥ 2% for further analyses. Kaplan–Meier survival analyses revealed a significantly higher mortality in patients with mutations in either of the seven genes (53 patients), combined as the CH‐risk gene set for CHF. Baseline patient characteristics showed no significant differences in any parameter including patient age, confounding diseases, severity of CHF, or blood cell parameters except for a reduced number of platelets in patients with mutations in the risk gene set in comparison with patients without. However, carrying a mutation in any of the risk genes remained significant after multivariate cox regression analysis (hazard ratio, 3.1; 95% confidence interval, 1.8–5.4; P < 0.001), whereas platelet numbers did not.

Conclusions

Somatic mutations with low VAF in a distinct set of genes, namely, in CBL, CEBPA, EZH2, GNB1, PHF6, SMC1A, and SRSF2, are significantly associated with mortality in CHF, independently of the most prevalent CHIP‐mutations in DNMT3A and TET2. Mutations in these genes are prevalent in young CHF patients and comprise an independent risk factor for the outcome of CHF, potentially providing a novel tool for risk assessment in CHF.
Influence of renal insufficiency pre‐heart transplantation on malignancy risk post‐heart transplantation
Authors: Roest Stefan , Struijk Christianne , Constantinescu Alina A. , Caliskan Kadir , Plasmeijer Elsemieke I. , Boersma Eric , Brugts Jasper J. , Manintveld Olivier C.
Published: March 2021

Aims

Recent reports demonstrated that patients with heart failure (HF) might have an increased risk to develop malignancies. This is also seen in patients with chronic kidney disease (CKD). Immunosuppression in heart transplantation (HT) recipients additionally increases the risk of malignancies. The aim of this study was to determine the relation between HF duration and CKD pre‐HT and the risk of malignancy development post‐HT.

Methods and results

We included all adult HT recipients transplanted between January 2000 and November 2017 in our centre. Patients were excluded if they died or were retransplanted within 3 months post‐HT. Clinical characteristics were retrospectively collected. Sixty out of 250 patients (24%) developed a malignancy after a median of 66 months [interquartile range 33–108] post‐HT. In multivariable Cox regression analysis, HF duration was not a risk factor for all malignancies or solid organ malignancies post‐HT [hazard ratio (HR) 1.033 (0.974–1.096), P = 0.281 and HR 1.036 (0.958–1.120), P = 0.376, respectively]. Age [HR 1.051 (1.016–1.086), P = 0.004] and CKD pre‐HT [HR 2.173 (1.236–3.822), P = 0.007] were independent risk factors for all malignancies. CKD pre‐HT [HR 2.542 (1.142–5.661), P = 0.022] increased the risk for solid organ malignancies. Exclusion of patients with durable mechanical circulatory support in the analysis did not alter the significance of these risk factors.

Conclusions

Duration of HF pre‐HT was not associated with malignancy risk post‐HT. CKD was an independent risk factor for malignancies post‐HT. More studies are needed to investigate this association.
A Novel Luminescent Metal‐Organic Framework as a Remarkable Sensor for Detecting Aristolochic Acids in Biological Fluids
Authors: Song Lijun , Liu Meiying , Tian Fuli , Liu Zhiliang
Published: March 2021

Abstract: Aristolochic acids (AAs) have caused widespread concern as highly nephrotoxic and carcinogenic substances. Therefore, it is essential to explore a simple and feasible method to detect AAs for disease prevention and clinical diagnosis. In this work, we designed and synthesized a novel luminescent metal organic framework (Zn‐MOF), which has excellent structural stability and fluorescence stability. Notably, the luminescent Zn‐MOF exhibits strong blue emission owing to ligand‐centered electronic transitions, while being capable as a selective sensor for the quantitative detection of AAs in biological fluids with low detection limit. The fluorescence analysis method, possessing the advantages of reliability and high accuracy, further demonstrated that Zn‐MOF has potential applications in monitoring the carcinogen biomarker AAs. Moreover, a paper‐based sensor has been devised by depositing Zn‐MOF on filter paper, which provides a novel strategy for visual, rapid, and on‐site AAs detection with the naked eye.
Pd‐Catalyzed Sonogashira Cross‐Coupling Reactions of gem‐Dibromovinyl BODIPY Derivatives
Authors: Ali Hasrat , Guérin Brigitte , van Lier Johan E.
Published: March 2021

4,4‐Difluoro‐4‐bora‐3a,4a‐diaza‐s‐indacene (BODIPY) derivatives bearing gem‐dibromovinyl moieties at either the β‐ or α‐positions of the pyrrole rings, directly or through phenyl spacers, undergo efficiently Sonogashira and Stille Pd‐catalyzed cross‐coupling. The structures of the resulting 1,1‐diynyl‐1‐alkene and 1,1‐diphenyl‐1‐alkene products were assigned using MS, NMR and in some cases X‐ray diffraction analysis. 1,1‐Diynyl‐1‐alkene BODIPYs exhibit red shifted absorption maxima, particularly when substituents were introduced at the α‐position rather than the β‐position of the pyrrole ring. Aromatic compounds showed larger red shifts as compared to the aliphatic substituted analogs. The highest red shifts were observed with compounds featuring electron donating substituents. Spectroscopic properties of α‐substituted 1,1‐diynyl‐p‐N,N‐dimethylaminophenyl‐1‐alkenes are sensitive to protonation resulting in remarkable pH‐responsive changes in the absorption and fluorescence emission spectra.
Low‐power gas microbubble detection technology based on acoustic resonance
Authors: Rivera Manuel , López Edwin , Cancelos Silvina , Marín Carlos
Published: March 2021

A novel approach towards developing a microbubble detection technology based on using a piezoelectric transducer to induce an acoustic resonance state within the system under investigation is here presented. The concept, originally proof‐of‐concept tested in a cylindrical acoustic resonant chamber, has proven to be able to detect single microbubbles with diameters in the range of 390–600 μm in a swine thigh, with either saline solution or sheep blood as the medium in the bubble guide. It has shown to be extremely adaptable, capable of accommodating industrial pipes as well as biological specimens, resilient and energy efficient, able to detect microbubbles with 0.8 mW and potentially less.
Association of serum selenium with anemia‐related indicators and risk of anemia
Authors: Zhou Qing , Zhang Baozhu , Chen Xi , Chen Qiuyan , Hao Lu
Published: March 2021

Few studies have examined the association of serum selenium with anemia‐related indicators and risk of anemia. We conducted a cross‐sectional analysis of 2,902 adults in 2003–2004 National Health and Nutrition Examination Survey database. Multivariable linear and logistic regression models were used to examine the association of serum selenium with anemia‐related indicators and risk of anemia. The nonlinear relationship was analyzed using a generalized additive model with the smoothing plot. A total of 1,472 males and 1,430 females with a mean age of 61.94 ± 13.73 years were included. Compared with the lowest quintile, the highest quintile of serum selenium was associated with increased level of serum iron (β = 12.44, 95% confidence interval [CI]: 7.14, 17.75, p < .001), mean corpuscular hemoglobin concentration (MCHC) (β = 0.14, 95%CI: 0.02, 0.26, p = .020), and hemoglobin (β = 0.40, 95%CI: 0.19, 0.61, p < .001), and decreased risk of anemia (odds ratio [OR] = 0.47, 95%CI: 0.28, 0.77, p = .002). Furthermore, smoothed plots suggested the nonlinear relationships between serum selenium and MCHC, hemoglobin level, and risk of anemia. Interestingly, on the left of inflection point, serum selenium was associated with decreased risk of anemia (OR = 0.972, 95%CI: 0.960, 0.985, p < .001), and then, the risk of anemia increased with increasing serum selenium concentration (OR = 1.011, 95%CI: 1.002, 1.021, p = .023). Future large‐scale, polycentric prospective studies should be conducted to verify our results.
Black Patients Have Unequal Access to Listing for Liver Transplantation in the United States
Authors: Rosenblatt Russell , Wahid Nabeel , Halazun Karim J. , Kaplan Alyson , Jesudian Arun , Lucero Catherine , Lee Jihui , Dove Lorna , Fox Alyson , Verna Elizabeth , Samstein Benjamin , Fortune Brett E. , Brown Robert S.
Published: March 2021

Background and Aims

The Model for End‐Stage Liver Disease score may have eliminated racial disparities on the waitlist for liver transplantation (LT), but disparities prior to waitlist placement have not been adequately quantified. We aimed to analyze differences in patients who are listed for LT, undergo transplantation, and die from end‐stage liver disease (ESLD), stratified by state and race/ethnicity.

Approach and Results

We analyzed two databases retrospectively, the Center for Disease Control Wide‐ranging Online Data for Epidemiologic Research (CDC WONDER) and the United Network for Organ Sharing (UNOS) databases, from 2014 to 2018. We included patients aged 25‐64 years who had a primary cause of death of ESLD and were listed for transplant in the CDC WONDER or UNOS database. Our primary outcome was the ratio of listing for LT to death from ESLD—listing to death ratio (LDR). Our secondary outcome was the transplant to listing and transplant to death ratios. Chi‐squared and multivariable linear regression evaluated for differences between races/ethnicities. There were 135,367 patients who died of ESLD, 54,734 patients who were listed for transplant, and 26,571 who underwent transplant. Patients were mostly male and White. The national LDR was 0.40, significantly lowest in Black patients (0.30), P < 0.001. The national transplant to listing ratio was 0.48, highest in Black patients (0.53), P < 0.01. The national transplant to death ratio was 0.20, lowest in Black patients (0.16), P < 0.001. States that had an above‐mean LDR had a lower transplant to listing ratio but a higher transplant to death ratio. Multivariable analysis confirmed that Black race is significantly associated with a lower LDR and transplant to death ratio.

Conclusions

Black patients face a disparity in access to LT due to low listing rates for transplant relative to deaths from ESLD.
Bacterially derived medical devices: How commercialization of bacterial nanocellulose and other biofabricated products requires challenging of standard industrial practices
Authors: Inselman Darric W. , Medberry Christopher J. , Czaja Wojciech K.
Published: March 2021

The objectives of innovation are often diametrically opposed to industrially standardized practices. The burgeoning field of Biofabrication represents one type of challenge that falls outside the norms of not only standardized industrial practices, but also those of Health Authorities. Biofabrication produces complex “biological products from raw materials such as living cells, molecules, extracellular matrices, and biomaterials” Mironov V, et al. Biofabrication, 2009, 1, 1–16. One such material is Bacterial Nanocellulose, a biologically derived cellulose structure with tissue like qualities, which does not fit within standardized manufacturing methods nor the well‐established parameters of medical device quality system regulations found within 21 CFR 820. Materials like this are necessary to address the hidden risks associated with their contending products, animal derived tissues, to move to a more sustainable manufacturing, and an animal cruelty free approach to medical device production. The goal of this manuscript, therefore, is to provide an example roadmap for navigating established quality system parameters while highlighting the need for Health Authorities to provide guidance to both industry and themselves as the field of advanced manufacturing continues to rapidly progress.
Improved dental student clinical skills performance through an integrated dental and medical student curriculum
Authors: Plant Alexandria N. , Caines Laurie C. , Wu Rong
Published: March 2021

Purpose/objectives

In light of a movement to eliminate the historical separation of dentistry and medicine to produce more collaborative and knowledgeable clinicians and to improve care, integrated education models are vital. This study aimed to demonstrate the effectiveness of an integrated medical and dental student curriculum at the University of Connecticut. It was hypothesized that a medical and dental student doctoring course within an already combined biomedical curriculum would result in statistically significantly increases in dental student clinical skills performance.

Methods

Analysis of variance (ANOVA) was utilized for an overall test of scores from 2016 to 2019. When ANOVA indicated significant differences, post hoc pairwise comparisons using Tukey's adjustment classified pairs that differed significantly. Lastly, a contrast was constructed to test the difference before and after the course's introduction. A two‐sided α of 0.05 was used.

Results

Dental students were assessed on three cases for history taking and master interview rating scale (MIRS) criteria. The mean averages in history taking and MIRS criteria after the implementation of this course increased by 7.81 (SE = 1.83, p < 0.0001) and 11.95 (SE = 1.34, p < 0.0001) for a toothache case, 11.37 (SE = 1.98, p < 0.0001) and 9.84 (SE = 1.35, p < 0.0001) for a loose bridge case, and 12.47 (SE = 1.75, p < 0.0001) and 10.07 (SE = 1.28, p < 0.0001) for a sensitive tooth case.

Conclusion

An integrated doctoring course within a combined curriculum at the University of Connecticut Schools of Medicine and Dental Medicine resulted in a statistically significant increase in dental student clinical skills assessment scores, demonstrating this model's utility.
Abbreviated Magnetic Resonance Imaging With Breath‐Hold Three‐Dimensional Magnetic Resonance Cholangiopancreatography: Assessment of Malignant Risk of Pancreatic Intraductal Papillary Mucinous Neoplasm
Authors: Yoo Jeongin , Min Ji Hye , Lee Dong Ho , Hur Bo Yun , Kim Se Woo , Kim Eunju
Published: March 2021

Background

For surveillance of pancreatic intraductal papillary mucinous neoplasms (IPMNs), magnetic resonance imaging (MRI)/magnetic resonance cholangiopancreatography (MRCP) is preferred over computed tomography, but the long acquisition time limits its use.

Purpose

To investigate the diagnostic performance of abbreviated MRI with breath‐hold (BH) three‐dimensional MRCP (abbreviated MRI‐BH) for malignant risk assessment of pancreatic IPMN.

Study Type

Retrospective.

Population

Two hundred and thirty‐five patients with IPMNs (M:F = 115:120; mean age ± SD, 66 ± 9 years; typical imaging features with ≥2‐year stability [N = 172] and histopathologically confirmed [N = 63]).

Field Strength/Sequence

3.0 T/ abbreviated MRI‐BH (single‐shot fast spin‐echo, T1W fat‐suppressed gradient‐echo sequence, and BH‐3D‐MRCP).

Assessment

Abbreviated MRI‐BH was reviewed by three reviewers, and its diagnostic performance was assessed using the predetermined scoring system. The diagnostic performance for the mural nodule detection was assessed. Additionally, diagnostic performance of abbreviated MRI was compared with that of full‐sequence MRI.

Statistical Tests

Area under the receiver operating characteristic curve (AUC) with z‐test, and linear‐weighted kappa values.

Results

Thirty‐five patients had malignant IPMN. At a cut‐off score ≥3, AUCs of abbreviated MRI‐BH for detecting malignant IPMN were 0.959 for reviewer 1, 0.962 for reviewer 2, and 0.956 for reviewer 3. The sensitivity of reviewers 1, 2, and 3 was 97.1% for all, and the specificity was 85.5%, 86.0%, and 85.0%, respectively. Regarding mural nodule detection (N = 22), abbreviated MRI‐BH demonstrated a sensitivity of 95.5% and a specificity of 88.3% for reviewer 1, a sensitivity of 86.4% and a specificity of 92.0% for reviewer 2, and a sensitivity of 86.4% and a specificity of 89.2% for reviewer 3. There were no significant differences between AUC of abbreviated MRI‐BH and that of full‐sequence MRI in the three reviewers (P > 0.05).

Data Conclusion

Abbreviated MRI‐BH showed good diagnostic performance for detecting malignant IPMNs by using a predetermined scoring system.

Level of Evidence

3

Technical Efficacy Stage

2
Late Quaternary chironomid community structure shaped by rate and magnitude of climate change
Authors: Mayfield Roseanna J. , Langdon Peter G. , Doncaster C. Patrick , Dearing John A. , Wang Rong , Velle Gaute , Davies Kimberley L. , Brooks Stephen J.
Published: March 2021

Much is known about how climate change impacts ecosystem richness and turnover, but we have less understanding of its influence on ecosystem structures. Here, we use ecological metrics (beta diversity, compositional disorder and network skewness) to quantify the community structural responses of temperature‐sensitive chironomids (Diptera: Chironomidae) during the Late Glacial (14 700–11 700 cal a bp) and Holocene (11 700 cal a bp to present). Analyses demonstrate high turnover (beta diversity) of chironomid composition across both epochs; however, structural metrics stayed relatively intact. Compositional disorder and skewness show greatest structural change in the Younger Dryas, following the rapid, high‐magnitude climate change at the Bølling–Allerød to Younger Dryas transition. There were fewer climate‐related structural changes across the early to mid–late Holocene, where climate change was more gradual and lower in magnitude. The reduced impact on structural metrics could be due to greater functional resilience provided by the wider chironomid community, or to the replacement of same functional‐type taxa in the network structure. These results provide insight into how future rapid climate change may alter chironomid communities and could suggest that while turnover may remain high under a rapidly warming climate, community structural dynamics retain some resilience.
Thermodynamic Parameters and Interfacial Properties of Poly(ethylene glycol)‐octyl Sulfosuccinates
Authors: Cai Hongyan , Luo Wenli , Zheng Yancheng , Zhang Yi , Lai Lu , Tang Shanfa
Published: March 2021

Surface tension of a series of poly(ethylene glycol)‐octyl sulfosuccinates at different temperatures was measured, and the interfacial properties were investigated in the absence and presence of inorganic salts. Surface tension results indicate that critical micelle concentration (CMC) values of five surfactants (C8‐PEG200, C8‐PEG400, C8‐PEG600, C8‐PEG800, and C8‐PEG1000) decrease as the molecular weight of polyethylene glycol (PEG) segments and the experimental temperature increases. The surface activity of the C8‐PEG series changes with temperature, and the surface tension at the CMC (γCMC) of the C8‐PEG series decreases initially and then increases as the PEG molecular weight increases. This behavior may be attributed to the dehydration of the surfactant molecules, resulting in the change of hydrophile–lipophile balance for the different EO numbers in the surfactant molecules, which form a different surface energy film at the air–water interface. Negative ΔGm indicates that the micellization process of these surfactants is spontaneous and an entropically driven process. For the water/alkane interface, these surfactants have low interfacial activity. The interfacial tension (IFT) between these surfactants and alkanes increases first and then decreases with the increase in the molecular weight of PEG segments. After the addition of salt, the interfacial activity of the investigated surfactants increases significantly. The IFT between C8‐PEG800 and 10–12 alkanes and between C8‐PEG1000 and 12–16 alkanes reaches a low IFT magnitude of 10−2 mN m−1 in the presence of 0.5% CaCl2 or the mixed inorganic salts 0.5% NaCl+0.5% CaCl2.
Gallic acid encapsulated pea flour‐based nanofibers produced by electrospinning as a potential active food packaging material
Authors: Aydogdu Emir Ayca , Yildiz Eda , Aydogdu Yıldırım , Sumnu Gulum , Sahin Serpil
Published: March 2021

The main aim of the article was to produce gallic acid‐loaded pea flour/polyethylene oxide (PEO)‐based nanofibers through the electrospinning method as an alternative active packaging material. Incorporation of gallic acid caused significant changes in both solution properties and fiber morphology. Increasing gallic acid concentration resulted in increasing conductivity and decreasing consistency index, by the way decreasing average fiber size diameter. In thermogravimetric analysis (TGA), gallic acid addition resulted in a decrease in thermal degradation value of nanofibers. In addition to these changes, new chemical bands formed were an indicator of the successful encapsulation of gallic acid in Fourier‐transform infrared (FTIR) spectra. Nanofibers also showed promising results in terms of encapsulation of bioactive compounds. Therefore, gallic acid‐loaded pea flour/PEO‐based nanofibers might be considered as a promising active packaging material.
At pivotal time in crisis response, report outlines community action steps
Authors: Enos Gary
Published: March 2021

A number of key developments nationally signal major improvements to behavioral health crisis response, but are communities adequately prepared to take full advantage of these enhancements? A new report published by the National Council for Behavioral Health offers the reminder that a great deal of work remains, and seeks to guide communities in evaluating their crisis system and implementing strategies for improvement.
System‐specific evaluation of the dual flip angle MRI technique for quantitative T1 measurement
Authors: Yee Seonghwan , Fadell Michael
Published: March 2021

Purpose

To investigate if the accuracy of the dual flip angle (DFA) technique for T1 measurement is affected by the system‐specific RF excitation performance.

Methods

A T1 phantom, made of 12 vials of unique T1 value ranging approximately from 200 ms to 2000 ms, was built and tested on seven different clinical scanners. For each experiment, the reference T1 of each vial was obtained by the inversion recovery‐based technique, and the DFA technique was applied repeatedly with several flip angle (FA) pairs conventionally proposed as optimal. The accuracy of the DFA technique for each FA pair was then evaluated by comparing the measured T1 values for the vials to the references. Any variation of the accuracy was then evaluated across different FA pairs, and across different MRI systems. To improve accuracy with a selected FA pair, the signal ratio (SR) curve, obtained from the phantom, was utilized in a calibration strategy of the DFA technique.

Results

When combined for all the vials, the average ratio of the measured T1 to the reference generally increased as the FA pair window gradually slid from the smaller to the larger FA values. Furthermore, among several optimal FA pairs, the pair of the best accuracy varied slightly by the MRI system. The accuracy for any FA pair could be improved when the calibration strategy was utilized.

Conclusions

The RF excitation performance may vary by the specific FA pair and by the specific MRI system, influencing the accuracy of the DFA technique. The system‐specific evaluation, and, if needed, its calibration, would help improve the accuracy of the DFA technique.
Improving generalization in MR‐to‐CT synthesis in radiotherapy by using an augmented cycle generative adversarial network with unpaired data
Authors: Brou Boni Kévin N. D. , Klein John , Gulyban Akos , Reynaert Nick , Pasquier David
Published: March 2021

Purpose

MR‐to‐CT synthesis is one of the first steps in the establishment of an MRI‐only workflow in radiotherapy. Current MR‐to‐CT synthesis methods in deep learning use unpaired MR and CT training images with a cycle generative adversarial network (CycleGAN) to minimize the effect of misalignment between paired images. However, this approach critically assumes that the underlying interdomain mapping is approximately deterministic and one‐to‐one. In the current study, we use an Augmented CycleGAN (AugCGAN) model to create a robust model that can be applied to different scanners and sequences using unpaired data.

Materials and methods

This study included T2‐weighted MR and CT pelvic images of 38 patients in treatment position from five different centers. The AugCGAN was trained on 2D transverse slices of 19 patients from three different sites. The network was then used to generate synthetic CT (sCT) images of 19 patients from the two other sites. Mean absolute errors (MAEs) for each patient were evaluated between real and synthetic CT images. Original treatment plans of nine patients were recalculated using sCT images to assess the dose distribution in terms of voxel‐wise dose difference, gamma, and dose–volume histogram analysis.

Results

The mean MAEs were Hounsfield units () and 65.8 HU for the first and second test sites, respectively. The maximum dose difference to the target was with a gamma pass rate using the 3%, 3 mm criteria above 99%. The average time required to generate a complete sCT image for a patient on our GPU was 8.5 s.

Conclusion

This study suggests that our unpaired approach achieves good performance in generalization with respect to sCT image generation.
Exposure Time of Wild, Juvenile Sockeye Salmon to Open-Net-Pen Atlantic Salmon Farms in British Columbia, Canada
Authors: Rechisky Erin L. , Porter Aswea D. , Johnston Stephen D. , Stevenson Christine F. , Hinch Scott G. , Hunt Brian P. V. , Welch David W.
Published: March 2021

The role that open-net-pen farms for Atlantic Salmon Salmo salar play in the global decline of stocks of wild salmonids (Salmo spp. and Oncorhynchus spp.) is contentious; Canada’s west coast is no exception. We identified the proportion of acoustic-tagged juvenile Sockeye Salmon Oncorhynchus nerka migrating through the main migration routes of the Discovery Islands region of British Columbia and measured both residence time in a major waterway hosting several Atlantic Salmon farms and exposure times to individual farms. One-third of tagged fish migrated through this channel, with median residence times of 32.6 h in 2017 and 46.0 h in 2018. The median time near individual farms was 4.4 min in 2017 when farms were fallow and 10.9 min in 2018 when farms were stocked. The increase in 2018 was probably not caused by farm activity because the proportion of total time spent in the channel was the same across years. Sockeye Salmon used all major migration pathways, but the lack of farms and rapid migration speeds in the westernmost passage offers the lowest potential exposure to fish farms. These are the first individual-level data available to inform assessments of the transmission risk of infectious agents from farms to wild salmonids.
“Bioelectrical impedance analysis in managing sarcopenic obesity in NAFLD”
Authors: Hanna David J. , Jamieson Scott T. , Lee Christine S. , Pluskota Christopher A. , Bressler Nicole J. , Benotti Peter N. , Khurana Sandeep , Rolston David D. K. , Still Christopher D.
Published: March 2021

Introduction

Sarcopenic obesity and its association with nonalcoholic fatty liver disease (NAFLD) is under‐recognized by many healthcare providers in Western medicine due to the lack of awareness and diagnostic guidelines. The result is delayed recognition and treatment, which leads to further health deterioration and increased healthcare costs. Sarcopenic obesity is characterized by the presence of increased fat mass in combination with muscle catabolism related to chronic inflammation and/or inactivity. Previous research has recommended evaluating body composition and physical function performance to adequately diagnose sarcopenic obesity. Body composition analysis can be performed by imaging applications through magnetic resonance imaging, computed tomography, and dual‐energy x‐ray absorptiometry. Due to the cost of each device and radiation exposure for patients as evidenced in all three modalities, bioelectrical impedance analysis offers a noninvasive approach capable of providing quick and reliable estimates of lean body and fat mass.

Methods and Results

This review analyzes the current evidence‐based literature, indicating a lower skeletal muscle mass and increased visceral adipose tissue correlation to the advancement of fibrosis in fatty liver disease.

Conclusion

Given the substantial promising research conducted in predominantly Asian populations regarding body tissue distribution and NAFLD, additional prospective research is needed to extend these findings in Western populations.
Improved impact property of long glass fiber‐reinforced polypropylene random copolymer composites toughened with beta‐nucleating agent via tunning the crystallization and phase
Authors: Yang Xujing , Chang Jiangyan , Fang Wenjun , Yu Zhiwei , Li Maojun , Li Qing
Published: March 2021

Crystallization and phase engineering offer a promising route to significantly improve the impact property of long glass fiber‐reinforced polypropylene random copolymer (LGF/PPR) composites. However, the nucleation and crystallization mechanism in the crystallization process, and the resulting phase change mechanism are still unclear, which severely limits the remarkable improvement of the toughness of LGF/PPR composites. Herein, we successfully fabricate toughened LGF/PPR composites with excellent heat deflection temperature and impact toughness via tuning the crystallization behavior and phase structure generated by introducing β‐nucleating agent (β‐NA). Through differential scanning calorimeter and wide‐angle X‐ray diffraction analysis, the influence of LGF and β‐NA on the nucleation and crystallization mechanism of the PPR matrix was revealed. Therefore, the critical crystallization parameters were calculated, and then the correlation was established with tensile and impact properties through regression analysis. The results show that the impact strength of β‐PPR and β‐LGF/PPR/MPPR are remarkably increased by 50.1% and 26.3% at the critical β‐NA content of 0.2 and 0.1 wt%, respectively, due to the intrinsic toughening mechanism. This work may pave the way for preparing a class of LGF/PPR composites with high‐impact toughness.
Prognostic indicators of subacute combined degeneration from B12 deficiency: A systematic review
Authors: Jhunjhnuwala Dhruv , Tanglay Onur , Briggs Nancy E. , Yuen Margaret T. Y. , Huynh William
Published: March 2021

Objective

A systematic review was conducted on published data of subacute combined degeneration (SCD) from B12 deficiency to investigate potential prognostic indicators of final ambulatory function in affected patients.

Type

Systematic review.

Literature Survey

Records published from 1999 through 2018 were searched on the electronic databases MEDLINE, PUBMED, and SCOPUS. The publication language was restricted to English and French.

Methodology

Records that described cases of SCD from B12 deficiency in patients ≥16 years of age at onset were included. From a final total of 66 cases of SCD identified, ambulation scores were assigned based on the clinical descriptions reported. Patient characteristics, clinical manifestations, and ambulatory function were reported descriptively. Subanalyses on potential prognostic indicators were performed.

Synthesis

Greater ambulatory function at diagnosis was associated with recovery of normal ambulatory function at follow‐up (P < .001). Nearly 90% of patients walking unsupported at diagnosis made a complete recovery regardless of etiology. For patients initially walking with support, 22% of cases from impaired B12 digestion/absorption made a complete recovery compared with ≥50% of cases from other etiologies. For patients initially requiring a wheelchair, 33% of cases from impaired digestion/absorption were able to walk with support compared with ≥50% of cases from other etiologies. The total B12 administered over the course of treatment was correlated with improved ambulation (P = .024) for all patients, with a higher B12 replacement regimen associated with better outcomes in patients who were unable to walk unsupported at diagnosis (number needed to treat = 4).

Conclusions

Initial ambulatory function may be a useful clinical marker of the severity of spinal cord dysfunction and final functional outcome. Etiological risk factors influenced both clinical manifestations and final walking ability in SCD, suggesting a distinct pathophysiological mechanism among the causes. In addition, a more intensive B12 replacement regimen may improve ultimate ambulatory function in advanced cases of SCD.
Bioresorbable tyrosol‐derived poly(ester‐arylate)s with tunable properties
Authors: Cohen Jarrod , Shultz Robert B. , Mullaghy Andrew , Gwin Christine , Kohn Joachim
Published: March 2021

We designed and developed a novel library of tyrosol‐derived poly(ester‐arylate)s that exhibit tunable chemical, thermal, mechanical, and degradative properties. To build the library, the diphenols 4‐hydroxyphenethyl 2‐(4‐hydroxyphenyl)acetate (HTy) and 4‐hydroxyphenethyl 3‐(4‐hydroxyphenyl)propanoate (DTy) are synthesized and subsequently polymerized with various diacids. Characterization of library members is performed in order to assess the impact of chemical structure on polymer properties. Specifically, the relative influence of diphenol pseudosymmetry versus asymmetry, diacid carbon chain length, and diacid bond rigidity on resulting properties is investigated. Diphenol choice greatly impacts resulting polymer thermal properties and processability. HTy‐containing polymers generally have lower melting temperatures compared to their DTy‐derived counterparts and are easier to quench in the amorphous phase. As a result, processing results in greater tunability for HTy‐derived polymers. One specific example was pHTy3, which increased its tensile modulus from 1 GPa to 3 GPa upon drawing. Diacid lengths and bond rigidity also significantly influence thermal, mechanical, and degradative properties. In all, members of this library can be synthesized efficiently, with high molecular weight and exhibit a wide range of properties, motivating future commercial translation.
Upgraded parameter model of frame pin‐supported wall structures
Authors: Zhou Ying , Yao Dansheng , Chen Yue , Li Qingqian
Published: March 2021

A frame pin‐supported wall structure (FPWS) is a typical rocking structure that releases constraints at the bottom of the wall. The existing studies have demonstrated that FPWSs can control the structural deformation effectively. A distributed parameter model (DPM), which consists of a flexural beam and a shear beam connected by infinitely rigid links, is used to describe the performance of FPWSs. The flexural and the shear beams represent the wall and the frame, respectively. However, there are several flaws in the DPM. For instance, (1) it is not appropriate to simplify the frame into a shear beam, (2) the infinitely rigid links cannot demonstrate the interaction between the frame and the wall properly, and (3) the stiffness variation along the height of the frame is not considered. In this study, an upgraded parameter model (UPM) was proposed to simulate the FPWS based on the DPM. Specifically, (1) a lumped mass model is employed to simulate the frame instead of the shear beam; (2) the pin‐supported wall (PW) and the frame are connected only at several positions, that is, at the floor levels; and (3) the variation of the stiffness is also considered in the UPM. The results via the UPM were compared with those using DPM and OpenSees model. A parametric analysis was then carried out using the UPM. The results indicated that the proposed UPM can describe the behavior of FPWSs accurately.
A Simple and High‐Accuracy PID‐Based Temperature Control System for Magnetic Hyperthermia Using Fiber Optic Thermometer
Authors: Shikano Akihiro , Tonthat Loi , Yabukami Shin
Published: March 2021

Magnetic hyperthermia is very promising cancer therapy in which heating temperature is expected to be a key determinant for its success. Herein, we present a simple, real‐time, and high‐accuracy proportional‐integral‐derivative‐based temperature control system for magnetic hyperthermia using widely‐used induction heater and fiber optic thermometer. Our in vitro result shows that the temperature of clinically‐approved Resovist® (0.5 ml) was accurately controlled with very small overshoot (e.g., 45.0 ± 0.07 °C and 55.0 ± 0.11°C for low‐ and high‐temperature magnetic hyperthermia). Our system has the potential to be used for magnetic hyperthermia either alone or together with other cancer treatment modalities for basic and clinical studies. © 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.