bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lanthanopolyoxometalate‐Silica Core/Shell Nanoparticles as Potential MRI Contrast Agents
Authors: Carvalho Rui F. S. , Pereira Giovannia A. L. , Rocha João , Castro M. Margarida C. A. , Granadeiro Carlos M. , Nogueira Helena I. S. , Peters Joop A. , Geraldes Carlos F. G. C. 
Published: July 2021

AbstractThe NMR relaxivities of the decatungstolanthanoate core‐shell nanoparticles, prepared by encapsulating [Ln(W5O18)2]9− polyoxometalates (LnPOM) within amorphous silica shells (K9[Ln(W5O18)2]@SiO2), were studied along the Ln series. The relaxivity of GdPOM is slightly higher than for Gd‐DTPA due to second‐sphere relaxation effects, but the values for the other paramagnetic LnPOMs are much smaller due to the short T1e values of their Ln3+‐ions. The NPs have core‐shell spherical structures, with LnPOM‐containing cores with 9.5–28 nm diameters, and 4.0–11.0 nm thick amorphous silica shells. In water suspensions, the NPs have negative zeta potentials (−32.5 to −40.0 mV) and time‐dependent hydrodynamic diameters (31–195 nm) reflecting the formation of aggregates. The relaxivities of GdPOM@SiO2 NPs suspensions (r1=10.97 (mM Gd)−1 s−1, r2=12.02 (mM Gd)−1 s−1, 0.47 T, 25 °C) are considerably larger than for the GdPOM solutions, indicating that their silica shell is significantly porous to water. This increase is limited by the agglomeration of the complexes in the NPs core, limiting their access to water to those at the core surface. Replacing half of the Gd3+ ions by Eu3+ decreases the NPs r1 and r2 relaxivities at 0.47 T to 20 % and 35 % of their initial values, which are still considerable, but does not affect the efficient luminescence properties of the Eu3+ centers. This indicates that the mixed NPs have potential as dual modality MRI/optical imaging contrast agents.
Hydrolysis of Uranyl‐, Nd‐, Ce‐Ions and their Mixtures by Thermal Decomposition of Urea
Authors: Schreinemachers Christian , Bollen Olivier , Leinders Gregory , Tyrpekl Václav , Modolo Giuseppe , Verwerft Marc , Binnemans Koen , Cardinaels Thomas 
Published: July 2021

AbstractThe hydrolysis of uranyl‐, Nd‐ and Ce‐cations, induced by thermal decomposition of urea was investigated and the impact of the urea content and the experiment temperature on the reaction kinetics was evaluated. Uranyl precipitated as ammonium diuranate (ADU) with varying stoichiometry. Nd(III) and Ce(III) showed comparable pH evolutions and lanthanide carbonate hydroxide (LnCO3OH) products were identified, whereas Ce(IV) hydrolysed at lower pH and formed CeO2. The precipitation behaviour was confirmed for mixtures of uranyl and the lanthanides. Depending on the urea content, a partial co‐precipitation occurred in U/Nd mixtures. The phases formed with Ce(III) and Ce(IV) were also identified in the precipitates of binary U/Ce mixtures. In ternary U/Nd/Ce compositions, a simultaneous precipitation of Nd(III) and Ce(III) was observed and a partial incorporation of the lanthanides into the ADU phase, whereas the precipitation in the presence of Ce(IV)/CeO2 led to the formation of three individual phases.
A Mild Glycosylation Protocol with Glycosyl 1‐Methylimidazole‐2‐carboxylates as Donors
Authors: Chen Jianpeng , Tang Yu , Yu Biao 
Published: July 2021

AbstractA mild glycosylation protocol is developed by using glycosyl 1‐methylimidazole‐2‐carboxylates. Such a glycosylation can be promoted by a series of metal triflates and triflimides, especially Cu(OTf)2. The reaction is initiated by activation of the glycosyl ester donor via coordination with the metal cation assisted by the adjacent 1‐methylimidazole chelating group.
Local intensity estimation of solar radiation with vision‐based3Dmodeling of local areas through unmanned aerial vehicle
Authors: Kim Sungkyum , Jang Seungsoo , Choi Chanho , Shin Sung Gyun , Lee Minjae , Cho Woosung , Lee Janghee , Han Sangsoo , Kim Jooyeon , Kim Song Hyun 
Published: July 2021

AbstractThe analysis of optimal locations for photovoltaic systems within urban regions has been raised as an important issue for increasing the relative efficiency of solar power generation in urban landscapes. This paper suggests a method that includes 3D modeling through unmanned aerial vehicle (UAV) flight strategies, shadow generation, solar radiation estimation, and evaluation of optimal areas to estimate cost‐effective candidate locations for installing solar panels. For testing the proposed method, combining generated shadows with the intensities of solar radiation in Pohang, South Korea, which were from data collected for a year, the average intensities were calculated to estimate regions for installing solar panels in the targeted places. It is expected that the strategy proposed in this study can contribute to the popularization on local intensity estimations of the solar radiation in urban landscape with using conventional UAV, which has high accessibility as well as realizing low estimation cost.
Entwicklungsstufen und Attribuierung des Fachmodells Baugrund – Empfehlungen Nr. 2 des Arbeitskreises 2.14 der DGGT „Digitalisierung in der Geotechnik“
Authors: Molzahn Michael , Bauer Jörg , Henke Sascha , Tilger Klaus 
Published: July 2021

AbstractIm Rahmen der zweiten Empfehlung des Arbeitskreises 2.14 der DGGT „Digitalisierung in der Geotechnik“ werden Entwicklungsstufen über den Lebenszyklus des Fachmodells Baugrund definiert sowie davon abhängig Mindestanforderungen an die Zuführung von geometrischen und semantischen Fachdaten (Attribuierung) in das Modell vorgeschlagen. Voraussetzung für eine durchgehende Anwendbarkeit des Fachmodells Baugrund im BIM‐Kontext ist die weitgehende Standardisierung der Fachdaten auf Modell‐ und Objektebene in Form von Eigenschaften. Die vorliegende Empfehlung zeigt die notwendigen Voraussetzungen für die noch zu entwickelnden, standardisierten, geotechnischen Eigenschaften auf und beschreibt die datentechnischen Anforderungen bei deren Erarbeitung sowie bei der Attribuierung des Fachmodells Baugrund durch den Anwender.
Thermal and thermoelastic problems in dry friction clutch: A comprehensive review
Authors: Jabbar Nasr A. , Hussain Ihsan Y. , Abdullah Oday I. 
Published: July 2021

AbstractThe friction clutch is considered a very important element of machines, as it plays a major role in transferring power from the driving part to the driven part. A common application of the friction clutch is in vehicles to connect between the gearbox and the engine. Fast wear occurs as a result of frictional heating that is generated when the clutch is starting to engage. This wear, in addition to the high thermal stresses, will lead to premature failure in the contacting surfaces. The present review highlights the most important studies of the thermal and thermoelastic problems of friction clutches during the last 10 years to show the challenges that were overcome and also the other challenges that needed to find solutions. The present paper will discuss in detail the influence of the frictional heat generated between contact surfaces during slipping and the main factors affecting the thermal behavior of dry friction clutches, such as sliding speed, friction materials, applied pressure, and so on. Furthermore, significant conclusions and remarks based on the available solutions to the thermal problem of the clutch are presented.
Delayed educational services during Covid‐19 and their relationships with the mental health of individuals with disabilities
Authors: Sakız Halis 
Published: July 2021

AbstractDuring the coronavirus disease 2019 (Covid‐19) pandemic, individuals with disabilities (IWD), like many others, have not been able to benefit effectively from educational and school‐based mental health services, which are vital to achieving mental good health. This study aimed to collect views of IWD about how their mental health was affected by the school closure during Covid‐19. Thirty‐one IWD were interviewed and data were analyzed thematically. Findings indicated that the educational delay, combined with the pressure of the preventive measures against Covid‐19 was associated with (i) difficulties in emotional well‐being, structured routines, learning, and socialization, (ii) enhanced feelings of isolation and pain, and (iii) negative perceptions of academic‐self‐efficacy and therapy‐related outcomes. The findings of the study highlight the importance of urgent short‐term and long‐term measures to provide safe and individually oriented educational services to compensate for the consequences of the pandemic.
Correlation between gastric residual volumes and markers of gastric emptying: A post hoc analysis of a randomized clinical trial
Authors: Lew Charles Chin Han , Lee Zheng‐Yii , Day Andrew G. , Heyland Daren K. 
Published: July 2021

AbstractBackgroundThe correlation between gastric residual volumes (GRVs) and markers of gastric emptying (GE) in critically ill patients is unclear. This particularly applies to critically ill surgical patients, as they are underrepresented in previous studies.MethodsWe conducted a post hoc analysis of a multicenter trial that investigated the effectiveness of a promotility drug. Pharmacokinetic markers of GE (3‐O‐methylglucose [3‐OMG] and acetaminophen) were correlated with GRV measurements. High GRV was defined as one episode of >400 ml or two consecutive episodes of >250 ml, and delayed GE was defined as <20th percentile of the pharmacokinetic GE marker that had the strongest correlation with GE.ResultsOf 77 patients, 8 (10.4%) had high GRV, and 15 (19.5%) had delayed GE. The 3‐OMG concentration at 60 min had the strongest correlation with GRV (ρ = −0.631), and high GRV had low sensitivity (46.7%) but high specificity (98.4%) in discriminating delayed GE. The positive (87.5%) and negative (88.4%) predictive values were similar. Compared with medical patients, surgical patients (n = 14, 18.2%), had a significantly higher incidence of high GRV (29% vs 6%, P = .032) and a trend toward delayed GE (36% vs 16%, P = .132).ConclusionGRV reflects GE, and high GRV is an acceptable surrogate marker of delayed GE. From our preliminary observation, surgical patients may have a higher risk of high GRV and delayed GE. In summary, GRV should be monitored to determine whether complex investigations or therapeutic interventions are warranted.
Low phase angle is associated with 60‐day mortality in critically ill patients with COVID‐19
Authors: Osuna‐Padilla Iván Armando , Rodríguez‐Moguel Nadia Carolina , Rodríguez‐Llamazares Sebastián , Aguilar‐Vargas Adriana , Casas‐Aparicio Gustavo Alejandro , Ríos‐Ayala Martin Armando , Hernández‐Cardenas Carmen Margarita 
Published: July 2021

AbstractBackgroundMalnutrition status, body composition indicators, and bioelectrical impedance analysis (BIA) parameters have been associated with increased risk of death in several pathologies. The aim of this study was to describe the associations between phase angle (PhA) indicators obtained by BIA with length of hospital stay, days on mechanical ventilation, and 60‐day mortality in critically ill patients infected with severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2).MethodsThis is a prospective cohort of mechanically ventilated patients with coronavirus disease 2019 (COVID‐19). We assessed nutrition risk and body composition with BIA within 48 h from intensive care unit admission. Logistic and linear regression models were used to analyze the association between variables and clinical outcomes. Survival analysis by PhA value was performed using Kaplan‐Meier curves.ResultsSixty‐seven patients were included. PhA (odds ratio [OR], 0.36; P = .002), standardized PhA (SPA) (OR, 0.45; P = .001), and extracellular water/total body water ratio (OR, 3.25; P = .002) were significant predictors of 60‐day mortality. PhA <3.85° in females and <5.25° in males showed good and fair discrimination, respectively, for mortality prediction. Using cutoff values, low PhA was associated with a significantly increased risk of 60‐day mortality (hazard ratio, 3.08; 95% CI, 1.12–8.41; P = .02). No association was detected for SPA.ConclusionLow PhA values could be a predictor of 60‐day mortality in critically ill patients with COVID‐19. This biological marker could be incorporated as part of nutrition and mortality risk assessment in this population.
Risk factors for lymph node metastasis in rectal neuroendocrine tumors: A recursive partitioning analysis based on multicenter data
Authors: Wang Ye , Zhang Yiyi , Lin Hexin , Xu Meifang , Zhou Xin , Zhuang Jinfu , Yang Yuanfeng , Chen Bin , Liu Xing , Guan Guoxian 
Published: July 2021

AbstractBackgroundThe well‐differentiated rectal neuroendocrine tumors (RNETs) can also have lymph node metastasis (LNM). Large multicenter data were reviewed to explore the risk factors for LNM in RNETs. Further, we developed a model to predict the risk of LNM in RNETs.MethodsIn total, 223 patients with RNETs from the Fujian Medical University Union Hospital, the First Affiliated Hospital of Fujian Medical University, and the First Affiliated Hospital of Xiamen University were retrospectively enrolled. Logistic regression analysis was performed to study the factors affecting LNM, and recursive partitioning analysis (RPA) was performed to stratify the risk of LNM.ResultsAmong the 223 patients diagnosed with RNETs, the incidence of LNM was 10.8%. Univariate and multivariate regression analyses revealed that tumor size, World Health Organization (WHO) grade, and depth of tumor invasion were independent risk factors for LNM (p < 0.05). The area under the curve was 0.948 (95% confidence interval: 0.890–1.000). Furthermore, the incidence of LNM in patients divided into low‐ and high‐risk groups according to RPA was 1.1% and 56.4%, respectively.ConclusionCompared with tumor size, the depth of tumor invasion and WHO grade are more important factors in predicting LNM. Then, we developed a model based on RPA to predict the risk of LNM in RNETs and identify patients who are suitable for local resection.
Surgical oncology operative experience at a high‐volume safety‐net hospital during the COVID‐19 pandemic
Authors: Kronenfeld Joshua P. , Collier Amber L. , Choi Seraphina , Perez‐Sanchez Dayana , Shah Ankit M. , Lee Christina , Goel Neha 
Published: July 2021

AbstractBackgroundThe coronavirus (COVID‐19) pandemic led to disruptions in operative and hospital capabilities as the country triaged resources and canceled elective procedures. This study details the operative experience of a safety‐net hospital for cancer‐related operations during a 3‐month period at the height of the pandemic.MethodsPatients operated on for or diagnosed with malignancies of the abdomen, breast, skin, or soft‐tissue (September 3, 2020–September 6, 2020) were identified from operative/clinic schedules. Sociodemographics, tumor and treatment characteristics, and COVID‐19 information was identified through retrospective chart review of a prospectively maintained database. Descriptive statistics were calculated.ResultsFifty patients evaluated within this window underwent oncologic surgery. Median age was 61 (interquartile range: 53–68), 56% were female, 86% were White, and 66% were Hispanic. The majority (28%) were for colon cancer. Only two patients tested positive for COVID‐19 preoperatively or within 30 days of their operation. There were no mortalities during the 1‐year study period.ConclusionDuring the COVID‐19 pandemic, many hospitals and operative centers limited interventions to preserve resources, but oncologic procedures continued at many large‐volume academic cancer centers. This study underscores the importance of continuing to offer surgery during the pandemic for surgical oncology cases at safety‐net hospitals to minimize delays in time‐sensitive oncologic treatment.
A strategy for efficient enrichment of steroidal alkaloids from Fritillaria based on fluorinated reversed‐phase stationary phase
Authors: Si Wei , Yu Dongping , Zhou Han , Guo Zhimou , Lu Shubin , Peng Ting , Liu Yanming , Shen Aijin , Liu Yanfang , Liang Xinmiao 
Published: July 2021

AbstractPlant‐derived alkaloids are bioactive natural ingredients, but their contents are relatively low in plants. Therefore, the efficient enrichment of alkaloids is a prerequisite for purification and further pharmacological research. In this study, an efficient and simple strategy for enrichment of steroidal alkaloids in Fritillaria was developed for the first time based on the fluorinated reverse‐phase stationary phase (FC8HL). Superior selectivity between alkaloids and non‐alkaloids was achieved in a non‐aqueous system, and a simple solvent system containing low‐content additives was applied to elute alkaloids. Key parameters that affected the elution were investigated, including different types of buffer salts and optimized concentrations. The optimized elution system was then applied to selectively enrich alkaloids from five species of Fritillaria. Its practicability was further demonstrated by enrichment of alkaloids from Fritillaria cirrhosa D.Don at a preparative level. This developed method has great potential for other types of hydrophobic alkaloids.
A dynamic susceptibility contrast MRI digital reference object for testing software with leakage correction: Effect of background simulation
Authors: Chen Henry Szu‐Meng , Jen Mu‐Lan , Hou Ping , Stafford R. Jason , Liu Ho‐Ling 
Published: July 2021

AbstractPurposeDynamic susceptibility contrast (DSC)‐MRI is a perfusion imaging technique from which useful quantitative imaging biomarkers can be derived. Relative cerebral blood volume (rCBV) is such a biomarker commonly used for evaluating brain tumors. To account for the extravasation of contrast agents in tumors, post‐processing leakage correction is often applied to improve rCBV accuracy. Digital reference objects (DRO) are ideal for testing the post‐processing software, because the biophysical model used to generate the DRO can be matched to the one that the software uses. This study aims to develop DROs to validate the leakage correction of software using Weisskoff model and to examine the effect of background signal time curves that are required by the model.MethodsThree DROs were generated using the Weisskoff model, each composed of nine foreground lesion objects with combinations of different levels of rCBV and contrast leakage parameter (K2). Three types of background were implemented for these DROs: (1) a multi‐compartment brain‐like background, (2) a sphere background with a constant signal time curve, and (3) a sphere background with signal time curve identical to that of the brain‐like DRO’s white matter (WM). The DROs were then analyzed with an FDA‐cleared software with and without leakage correction. Leakage correction was tested with and without brain segmentation.ResultsAccuracy of leakage correction was able to be verified using the brain‐like phantom and the sphere phantom with WM background. The sphere with constant background did not perform well with leakage correction with or without brain segmentation. The DROs were able to verify that for the particular software tested, leakage correction with brain segmentation achieved the lowest error.ConclusionsDSC‐MRI DROs with biophysical model matched to that of the post‐processing software can be well used for the software's validation, provided that the background signals are also properly simulated for generating the reference time curve required by the model. Care needs to be taken to consider the interaction of the design of the DRO with the software's implementation of brain segmentation to extract the reference time curve.
The effect of a game training intervention on cognitive functioning and depression symptoms in the elderly with mild cognitive impairment: A randomized controlled trial
Authors: Xue Bing , Xiao Ao , Luo Xianwu , Li Rui 
Published: July 2021

AbstractObjectivesThis study aimed to explore whether game training could improve cognitive functioning and depression symptoms in the elderly affected by mild cognitive impairment (MCI).MethodsA non‐blinded randomized controlled trial was conducted. Participants were 72 patients with MCI and depression from a nursing home in Wuhan. Participants were randomized to either the intervention group or the control group (n = 36 each). The intervention group received regular nursing care plus game training for 50 min, three times per week for 8 weeks, whereas the control group received only regular nursing care during the same research period. Cognitive functioning and depression symptoms were tested in both groups at baseline and at the end of the 8‐week intervention. We used the Montreal Cognitive Assessment and the 15‐item Geriatric Depression Scale to assess cognitive functioning and depression symptoms, respectively.ResultsThe 8‐week game training intervention significantly improved the cognitive and depression scores when compared with the control group and baseline scores (p < 0.05). No significant difference was observed in the control group (p > 0.05).ConclusionsOur results suggest that the implementation of game training can improve the cognitive functioning and depression symptoms of the elderly with MCI, indicated that can be widely used.
Development and psychometric evaluation of the Feeling Safe During Surgery Scale
Authors: Larsson Fanny , Engström Åsa , Strömbäck Ulrica , Gustafsson Silje 
Published: July 2021

AbstractAimThe aim of this study is to develop and psychometrically test the Feeling Safe During Surgery Scale.DesignThe study design was non‐experimental and cross‐sectional.MethodThe evaluation followed classical test theory, and the instrument was evaluated regarding reliability, construct validity and content validity. For the reliability analysis, a postal questionnaire consisting of the 16 items of the scale was dispatched in March 2020 to a consecutive sample (N = 242) of patients who had undergone hip or knee replacement arthroplasties with regional anaesthesia. Five experts in nursing care evaluated the content validity of the scale.ResultInternal consistency was 0.841. Three items were excluded due to deficits in reliability, resulting in a 13‐item scale. A principal component analysis revealed a two‐dimensional solution, labelled internal and external aspects of feeling safe. Two items were rephrased to improve clarity and content validity. The average content validity for the scale was 0.88, indicating acceptable content validity.
An m‐Health Intervention for Rheumatoid Arthritis in China (“Rheumatism Center” app): Study Protocol for a Prospective Randomized Controlled Trial
Authors: Luo Huifang , Ma Qing , Song Jiating , Peng Jie , Song Yang , Chen Guangxing , Lin Changsong , Yang Xiangwei 
Published: July 2021

AbstractAimTo study the feasibility and effectiveness of a m‐Health app in improving the management of rheumatoid arthritis.DesignRandomized controlled trial.MethodsSixty rheumatoid arthritis participants will be recruited for a 6‐month feasibility study. Patients meeting the inclusion criteria will be randomly allocated to receive standard care or standard care plus the m‐Health intervention. The primary outcome is the feasibility of a randomized controlled trial. In addition, we will investigate patient satisfaction in using the “Rheumatism Center” app in the intervention group. The secondary outcomes include the scores for the simplified disease activity index, clinical disease activity index, disease activity score 28, health assessment questionnaire and 6‐item self‐efficacy scale for chronic diseases. The assessments will be performed at baseline and at 4 weeks, 3 months and 6 months after the study is initiated. At the end of the study, we will also collect user views of the app through qualitative interviews.ResultsThis study is ongoing. The findings of this study will determine the feasibility and effectiveness of m‐Health intervention in the management of rheumatoid arthritis, hoping to enhance the awareness of disease management and quality of life for rheumatoid arthritis patients.