bluuebunny/crossref_metadata_2025 huggingface dataset:
Dbx2 regulation in limbs suggests interTAD sharing of enhancers
Authors: Beccari Leonardo , Jaquier Gabriel , Lopez‐Delisle Lucille , Rodriguez‐Carballo Eddie , Mascrez Bénédicte , Gitto Sandra , Woltering Joost , Duboule Denis
Published: January 2021

Background

During tetrapod limb development, the HOXA13 and HOXD13 transcription factors are critical for the emergence and organization of the autopod, the most distal aspect where digits will develop. Since previous work had suggested that the Dbx2 gene is a target of these factors, we set up to analyze in detail this potential regulatory interaction.

Results

We show that HOX13 proteins bind to mammalian‐specific sequences at the vicinity of the Dbx2 locus that have enhancer activity in developing digits. However, the functional inactivation of the DBX2 protein did not elicit any particular phenotype related to Hox genes inactivation in digits, suggesting either redundant or compensatory mechanisms. We report that the neighboring Nell2 and Ano6 genes are also expressed in distal limb buds and are in part controlled by the same Dbx2 enhancers despite being localized into two different topologically associating domains (TADs) flanking the Dbx2 locus.

Conclusions

We conclude that Hoxa13 and Hoxd genes cooperatively activate Dbx2 expression in developing digits through binding to mammalian specific regulatory sequences in the Dbx2 neighborhood. Furthermore, these enhancers can overcome TAD boundaries in either direction to co‐regulate a set of genes located in distinct chromatin domains.
Facile Fabrication of Ag Nanocrystals Encapsulated in Nitrogen‐doped Fibrous Carbon as an Efficient Catalyst for Lithium Oxygen Batteries
Authors: Liu Lili , Ma Tianyi , Fang Weiwei , Liu Yuqing , Konstantinov Kostantin , Wang Jiazhao , Liu Hua‐Kun
Published: January 2021

A facile synthesis of Ag nanocrystals encapsulated in nitrogen‐doped carbon fiber (NCF) is proposed, based on the simultaneous reaction between pyrrole and Ag+ ions in an aqueous solvent followed by a heat treatment. The as‐prepared Ag/NCF demonstrated superior catalytic behavior toward ORR and OER. Besides improved cycling stability, a much lower discharge/charge gap of 0.89 V (vs Li/Li+) compared with 1.38 V for NCF cathode with a fixed capacity of 500 mAh g−1 was obtained in lithium oxygen batteries. The introduction of Ag crystals into NCF facilitates the oxygen reduction reaction/oxygen evolution reaction kinetics. X‐ray diffraction analysis coupled with Raman spectroscopy confirmed that Ag/NCF cathode could reversibly catalyze Li2O2 formation and decomposition. The NCF matrix offers a conductive network to realize rapid mass transfer and the encapsulated Ag nanocrystals supplied effective catalytic active sites. The combined action between both contributes to the superior electrocatalytic performance.
The prevalence, predictors, and outcomes of spontaneous echocardiographic contrast or left ventricular thrombus in patients with HFrEF
Authors: Zhou Xiaodong , Shi Ruiyu , Wu Gaojun , Zhu Qianli , Zhou Changzuan , Wang Liangguo , Xue Chenglong , Jiang Yuanyuan , Cai Xueli , Huang Weijian , Shan Peiren
Published: January 2021

Aims

This study aimed to determine prevalence, predictors, and association with ischaemic stroke risk of spontaneous echocardiographic contrast (SEC) or left ventricular thrombus (LVT) in patients with heart failure with reduced ejection fraction (HFrEF).

Methods and results

Clinical, echocardiographic, and follow‐up data from January 2009 through February 2019 were retrospectively extracted from electronic medical records of patients with heart failure with left ventricular ejection fraction < 40% by echocardiography on admission, with follow‐up to February 2020. Of 9485 consecutive patients with HFrEF, 123 (1.3%) presented LVT and 331 (3.5%) presented SEC. Patients with vs. those without SEC/LVT had larger left ventricular end‐diastolic volume (199.5 ± 77.7 vs. 165.8 ± 61.3 mL, P < 0.001), lower left ventricular ejection fractions (29.5 ± 7.0% vs. 33.7 ± 5.5%, P < 0.001), and more often ischaemic cardiomyopathy, apical aneurysm, chronic kidney diseases, and smoking habit. In Cox regression analysis, SEC and LVT were independent predictors for ischaemic stroke occurrence [hazard ratio (HR) = 2.40, 95% confidence interval (CI): 1.74–3.31; HR = 4.52, 95% CI: 2.77–7.40, both P < 0.001]. In patients with those without SEC or LVT, stroke risk was higher among those not on anticoagulants (HR = 2.55, 95% CI: 1.85–3.53; HR = 4.71, 95% CI: 2.84–7.81, both P < 0.001), but similar among those on anticoagulants (P > 0.05). In patients with sinus rhythm, the associations between SEC/LVT and ischaemic stroke persist with HRs of 2.57 (95% CI: 1.69–3.92) and 5.74 (95% CI: 3.38–9.75).

Conclusions

In patients with HFrEF, SEC was not uncommon and increased risk of ischaemic stroke as well as LVT. Anticoagulants could play a role in the reduction of stroke risk, suggesting that patients with SEC/LVT, even those in sinus rhythm, would benefit from systemic anticoagulation treatment.
Label‐free Selective Detection of Protein Markers in the Picomolar Range via a Convenient Voltammetric Sensing Strategy
Authors: Chen Chun‐Yu , Lehr Joshua
Published: January 2021

A convenient strategy for the preparation of label‐free selective protein biomarker sensors is presented. After formation of a ferrocene terminated monolayer on a gold electrode using thiol chemistry, grafting of an antifouling phenylalanine layer onto the preformed ferrocene monolayer is achieved by diazonium chemistry. This provides a platform for receptor (anti‐BSA or anti‐CRP) immobilization as well an antifouling interface. Specific target binding leads to attenuation of the voltammetric faradaic signal of the underlying ferrocene group. Thereby, label‐free, selective, voltammetric detection is achieved with highly competitive limits of detection in the low (≤4) picomolar range for both BSA and CRP.
Increased DNA strand breaks and neoplastic transformation in human bladder cells treated with pioglitazone
Authors: Atlı Şekeroğlu Zülal , Şekeroğlu Vedat , Kontaş Yedier Seval , İlkun Emre , Liou Louis S.
Published: January 2021

Pioglitazone (PIO), an oral hypoglycemic agent, is used in the treatment of type 2 diabetes. Some studies have suggested that an increased risk of bladder cancer with PIO exposure, while the others reported there is no such relationship. Therefore, it is doubtful whether PIO can increase the risk of bladder cancer. The effects of PIO on DNA damage and/or transformation of human bladder cells are not fully known. We investigated the effects of PIO on cytotoxicity, DNA single and double strand breaks and repair and neoplastic transformation in human bladder cells (hTU1) treated with 10, 20, and 40 μM PIO for 24, 48 and 72 hr. PIO decreased cell viability in a concentration‐dependent manner. Increased levels of comet parameters showed that PIO and its metabolites can significantly induce DNA double strand breaks at all concentrations tested. PIO also significantly induced the formation of phosphorylated H2AX and p53 binding protein 1 foci. DNA damage was not repaired in a 24 hr recovery period. PIO can also induce malignant transformation of human bladder cells exhibiting loss of contact inhibition and anchorage independent growth. This is the first study to indicate that PIO can induce DNA damage and malignant transformation, reduce or alter the DNA repair capacity in human bladder cells. From these results, we suggest that patients with diabetes treated with PIO may have an increased risk of bladder cancer.
Micronucleated erythrocytes in peripheral blood from neonate rats fed by nursing mothers exposed to X‐rays
Authors: Solórzano‐Meléndez Alejandro , Rodrigo‐Alarcón Rodolfo , Gómez‐Meda Belinda C. , Zamora‐Pérez Ana L. , Ortiz‐García Ramón G. , Bayardo‐López Luis H. , González‐Virgen Roberto , Gallegos‐Arreola Martha P. , Zúñiga‐González Guillermo M.
Published: January 2021

Most women with breast cancer can become pregnant and give birth while undergoing radiation therapy and breastfeeding is generally not contraindicated. The induction of long‐lived reactive species in proteins, such as casein by X‐ray radiation and DNA damage to unexposed organisms, has been shown when ingesting irradiated cheese. To determine whether exposing lactating rats to X‐rays increases the number of micronucleated erythrocytes (MNEs) in peripheral blood of their unexposed or breastfeeding rat pups, 15 female Wistar rats were divided into three groups: Negative control; Experimental group exposed to X‐rays, and group exposed to X‐rays plus vitamin C. The mothers of groups 2 and 3 were irradiated for three consecutive days after giving birth, returning them to their respective cages each time to continue lactation. A blood sample was taken from the mothers and pups at 0, 24, and 48 hr. Blood smears were stained with acridine orange to analyze MNEs. In mother rats, the frequency of micronucleated polychromatic erythrocytes (MNPCEs) increased significantly at 24 and 48 hr in both study groups exposed to radiation. Likewise, in rat pups the MNPCE and MNE frequencies increased in both groups with radiation and radiation plus vitamin C at 24 and 48 hr, and a protection from vitamin C was observed. In conclusion, the genotoxic damage produced in rat pups that were lactated by mothers irradiated with X‐rays is possibly due to the effect of long‐lived reactive species that were formed in the breast milk of female Wistar rats during the irradiation process.
Does reduced intraspecific competition of the dominant species in intercrops allow for a higher population density?
Authors: Wang Qi , Bai Wei , Sun Zhanxiang , Zhang Dongsheng , Zhang Yue , Wang Ruonan , Evers Jochem B. , Stomph Tjeerd‐Jan , van der Werf Wopke , Feng Chen , Zhang Lizhen
Published: January 2021

Dominant species in intercropping experience less resource competition compared with its monoculture. This reduced competition for resources may allow cultivating the dominant species at an increased density in intercropping to obtain greater yield. However, experimental results are inconclusive when the optimal within row density in the sole crop is not well established. Here, we conducted a two‐year experiment to test the hypothesis that optimal within row plant density of dominant species in intercropping would be higher in the intercrop than in the sole crop. We tested three maize densities (3, 4.5, and 6 plants m−1) in both sole maize and two replacement designed intercrops. The row configurations of two intercrops are two rows maize intercropped with four rows peanut (M2P4) and four rows maize intercropped with four rows peanut (M4P4). Peanut was grown at the same plant density of 12 plants m−1 row in both sole crop and intercrops. The results indicated that increasing maize density from the optimal density in monoculture is not worthy of promotion to improve yield in intercropping, which denied our hypothesis. The land equivalent ratios (LER) in the dry year (2017) were higher than the wet year (2016). Maize yields per unit area of the whole intercropping system were highest with densities of 4.5 and 6 plants m−1 row, with no significant difference between these two densities. Maximum maize yields in sole cropping were obtained with maize densities of 6 plants m−1 row. Intercropping provided higher yields at low and intermediate sole crop maize densities, but not at high sole crop maize density. Average land equivalent ratios at 3, 4.5, and 6 plants m−1 of maize were 1.09, 1.04, and 0.95 in 2016, and 1.07, 1.10, and 1.02 in 2017. Our results suggest that intercropping performs better at conditions with less resources than adequate resources.
Empirical Evidence for Depensation in Freshwater Fisheries
Authors: Sass Greg G , Feiner Zachary S , Shaw Stephanie L
Published: January 2021

Inland fisheries face increasing threats to their sustainability. Despite speculation that depensation may exacerbate the effects of stressors on population resiliency, depensation has not been empirically explored in freshwater fisheries. Declining productivity of Walleye Sander vitreus populations in northern Wisconsin foreshadows an underlying change in naturally reproduced juvenile Walleye survival. We used long-term stock and recruitment data from lakes in the Ceded Territory of Wisconsin to quantify density-dependent trends in juvenile Walleye survival and tested for the prevalence of depensation using the q parameter of Liermann and Hilborn (1997). Of 82 Walleye populations evaluated, about half exhibited depensatory recruitment. An analysis of the global q for all populations examined suggested that the posterior probability of depensatory dynamics was about 0.89. In addition, there were few clear cases of compensation—most populations exhibited weak density dependence. The general lack of strong compensatory recruitment across Walleye populations could leave these stocks vulnerable to stressors and unresponsive to rehabilitation. We present multiple lines of evidence to suggest that depensation is a plausible phenomenon explaining declines in Walleye populations in the Ceded Territory of Wisconsin and may be implicated in other invisible collapses of freshwater fisheries.
Geochronological study of biotite aegirine‐augite syenite in the Bengge area, Western Yunnan: An example of zircon U–Pb dating for alkalic rocks
Authors: Liu Xiao , Luo Zhaohua , Wang Yu , Jiang Xiumin
Published: January 2021

The Bengge biotite aegirine‐augite syenite (BAS) is located in the southern part of Yidun Arc, eastern margin of the Tibetan Plateau area. It is an integral part of the Bengge ultrapotassic rocks (UPR), an alkalic complex mainly consisting of BAS, biotite pyroxene syenite (BPS), and biotite syenite (BS). Geochronological studies including zircon LA‐ICPMS U–Pb dating and biotite 40Ar/39Ar dating have been conducted on the Bengge BAS to constrain its emplacement age. The zircon U–Pb dating yields a wide range of ages from 209 ± 2 Ma to 239 ± 2 Ma, with the concordia 206Pb/238U age being 228 ± 8.9 Ma (MSWD = 0.13). Meanwhile, the biotite 40Ar/39Ar dating yields a plateau age of 205.7 ± 1.5 Ma. The whole‐rock Zr‐saturation temperature (Tzir‐sat) of the Bengge BAS has shown to be very low (86 ± 13°C to 634 ± 13°C), which is much lower than Ti‐in‐zircon temperature (>758°C) of the zircons used for U–Pb dating. This indicates that the zircons in the Bengge BAS are inherited, and they were already present in the BAS melts before the melts became Zr‐saturated. Similarly, the Tzir‐sat of the Bengge BPS and BS are 346 ± 14°C ~ 549 ± 13°C and 281 ± 14°C ~ 525 ± 13°C, respectively, which is also too low for magmatic zircon crystallization in the melts. The inherited zircons of Bengge BAS have typical features of magmatic zircon, with high (Sm/La)N ratios (2.54–819), Ce/Ce* ratios (4.77–304) and low La concentration. Low εHf (T) values (−5.0 to 0.42) and high U/Yb (0.67–12.6) values imply that the inherited zircons (209–239 Ma) in the Benge BAS are derived from an early arc‐magma system of the Yidun Arc. The biotite 40Ar/39Ar dating constrains the Bengge BAS emplacement age at 205.7 ± 1.5 Ma, the time when the arc‐magma activity had ceased, and a regional geodynamic transition in the Yidun Arc from convergence to back‐arc spreading had started.
Respiratory‐swallow coordination and swallowing impairment in head and neck cancer
Authors: Hopkins‐Rossabi Theresa , Armeson Kent E. , Zecker Steven G. , Martin‐Harris Bonnie
Published: January 2021

Background

The aim of the study was to determine the link between frequency of optimal respiratory‐swallow coordination, swallowing impairment, and airway invasion in head and neck cancer (HNC) patients.

Method

A cross‐sectional study of a heterogeneous group of HNC patients (49), precancer (N = 30) or postcancer treatment (N = 29), participated in a single Modified Barium Swallow Study (MBSS) with synchronized respiratory data.

Results

Spearman correlation coefficients revealed significant negative correlations between optimal respiratory‐swallow phase pattern and objective measures of swallowing impairment: penetration‐aspiration scale max, pharyngeal total, and oral total scores with Spearman correlation coefficients of −0.53 (z .001), −0.50 (P < .001), and −0.43 (P = .002), respectively. Optimal respiratory‐swallow pattern was significantly decreased (P = .03) in patients after cancer treatment compared with another patient group before cancer treatment.

Conclusion

These findings indicate that as the percentage of optimal respiratory‐swallow phase patterns increase, swallowing impairment decreases in the HNC patient population.
Safety of switching to brexpiprazole in Japanese patients with schizophrenia: A post‐hoc analysis of a long‐term open‐label study
Authors: Ishigooka Jun , Inada Ken , Niidome Kazunari , Aoki Kazuo , Kojima Yoshitsugu , Iwashita Shuichi , Yamada Sakiko
Published: January 2021

Objectives

To determine the long‐term safety of switching to brexpiprazole from aripiprazole or non‐aripiprazole dopamine antagonists.

Methods

Post‐hoc analysis of 56‐week study of Japanese outpatients with schizophrenia switched to brexpiprazole 2 mg/day over 4‐week switching period with further titration (1–4 mg/day) allowed during the 52‐week, open‐label period. Major assessment items: total/low‐density lipoprotein (LDL)‐/high‐density lipoprotein (HDL)‐cholesterol, triglycerides, blood glucose, body weight and prolactin. Secondary evaluations were related to efficacy, treatment emergent adverse events (TEAEs), extrapyramidal symptoms, and corrected QT interval (QTc).

Results

84/186 (45.2%) patients (aripiprazole, 32.9%; non‐aripiprazole, 54.8%) discontinued treatment over 56 weeks mainly because of consent withdrawal/adverse events. From baseline to Week 56, both groups showed minimal mean changes in total/LDL‐/HDL‐cholesterol, triglycerides, and glucose levels and a slight increase in mean (SD) body weight (aripiprazole, 1.1 [4.4] kg; non‐aripiprazole, 0.4 [4.6] kg). Mean prolactin levels increased slightly in the aripiprazole group, but decreased in the non‐aripiprazole group. Symptom severity scores decreased similarly in both groups. TEAEs occurred in 161/186 (86.6%) patients (aripiprazole, 84.1% [serious, 9.8%]; non‐aripiprazole, 88.5% [serious, 14.4%]). Few changes occurred in extrapyramidal symptom scales or QTc interval.

Conclusions

Switching to brexpiprazole is associated with a low long‐term risk for metabolic abnormalities (including weight gain), hyperprolactinemia, extrapyramidal symptoms and QTc changes and minimal changes in psychiatric symptoms.
Response of soil aggregate disintegration to the different content of organic carbon and its fractions during splash erosion
Authors: Li Hairu , Liu Gang , Gu Ju , Chen Hong , Shi Hongqiang , Abd Elbasit Mohamed A. M. , Hu Feinan
Published: January 2021

Aggregate disintegration is a critical process in soil splash erosion. However, the effect of soil organic carbon (SOC) and its fractions on soil aggregates disintegration is still not clear. In this study, five soils with similar clay contents and different contents of SOC have been used. The effects of slaking and mechanical striking on splash erosion were distinguished by using deionized water and 95% ethanol as raindrops. The simulated rainfall experiments were carried out in four heights (0.5, 1.0, 1.5 and 2.0 m). The result indicated that the soil aggregate stability increased with the increases of SOC and light fraction organic carbon (LFOC). The relative slaking and the mechanical striking index increased with the decreases of SOC and LFOC. The reduction of macroaggregates in eroded soil gradually decreased with the increase of SOC and LFOC, especially in alcohol test. The amount of macroaggregates (>0.25 mm) in deionized water tests were significantly less than that in alcohol tests under the same rainfall heights. The contribution of slaking to splash erosion increased with the decrease of heavy fractions organic carbon. The contribution of mechanical striking was dominant when the rainfall kinetic energy increased to a range of threshold between 9 J m−2 mm−1 and 12 m−2 mm−1. This study could provide the scientific basis for deeply understanding the mechanism of soil aggregates disintegration and splash erosion.
Long‐term database of Beasley Lake Watershed with 25 years of agricultural conservation practices
Authors: Lizotte Jr Richard E. , Yasarer Lindsey M. W. , Griffith Mark K. , Locke Martin A. , Bingner Ronald L.
Published: January 2021

Beasley Lake Watershed is an agriculturally influenced drainage basin in western Mississippi that has been intensively studied for 25 years. As part of the USDA Conservation Effects Assessment Project (CEAP), the watershed has archived hydrology, precipitation, and water quality data in order to measure the effects of multiple USDA Natural Resources Conservation Service conservation practices on lake water quality. The long‐term database is available to researchers using a web‐based application, Sustaining the Earth's Watersheds, Agricultural Research Data System (STEWARDS). STEWARDS is a GIS‐based data retrieval application that encompasses spatial and temporal data collected from multiple sites within the watershed. This data note describes information located in the STEWARDS Beasley Lake Watershed database, including hydrology, precipitation, and water quality data. This information is valuable to researchers and agencies beyond the USDA as an available and useful database to improve the understanding of how land‐use practices affect the water quality of shallow lake systems.
Long‐run co‐variability between oil prices and economic policy uncertainty
Authors: Shahbaz Muhammad , Sharif Arshian , Belaid Fateh , Vo Xuan Vinh
Published: January 2021

This study investigates the long run co‐variability between prices of oil and uncertainty of economic policy by using monthly data for the period of 1998M1‐2018M12. We develop an innovative approach based on long‐run co‐variability approach developed recently by Muller and Watson (Müller & Watson, 2018). Our empirical results reveal the positive long‐run relationship between oil prices and uncertainty of economic policy for Australia, India, and Hong Kong whereas, a negative relationship is found between both variables in Brazil, China, Europe, Japan, Korea, Mexico, Russia, Sweden, and United States. We also find an insignificant effect of oil prices on uncertainty of economic policy in Chile, Colombia, Greece, Ireland, Netherland, and Singapore. This study extends the recent empirical findings on oil prices‐economic policy uncertainty, which imply a differential influence of oil prices on uncertainty economic policy in sampled countries. From policy perspectives, results of this paper are helpful to policy makers with long‐term concerns. They may guide the policy makers to identify the suitable policies to deal with substantial economic policy uncertainty and large oil prices shakes. In addition, they offer possibilities for drawing on the empirical evidence to deepen their understanding of dynamic relationship among oil prices and uncertainty of economic policy.
Resurgence and repeated within‐session progressive‐interval thinning of alternative reinforcement
Authors: Nist Anthony N. , Shahan Timothy A.
Published: January 2021

Resurgence of a previously suppressed target behavior is common when reinforcement for a more recently reinforced alternative behavior is thinned. To better characterize such resurgence, these experiments examined repeated within‐session alternative reinforcement thinning using a progressive‐interval (PI) schedule with rats. In Experiment 1, a transition from a high rate of alternative reinforcement to a within‐session PI schedule generated robust resurgence, but subsequent complete removal of alternative reinforcement produced no additional resurgence. Experiment 2 replicated these findings and showed similar effects with a fixed‐interval (FI) schedule arranging similarly reduced session‐wide rates of alternative reinforcement. Thus, the lack of additional resurgence following repeated exposure to the PI schedule was likely due to the low overall obtained rate of alternative reinforcement provided by the PI schedule, rather than to exposure to within‐session reinforcement thinning per se. In both experiments, target responding increased at some point in the session during schedule thinning and continued across the rest of the session. Rats exposed to a PI schedule showed resurgence later in the session and after more cumulative alternative reinforcers than those exposed to an FI schedule. The results suggest the potential importance of further exploring how timing and change‐detection mechanisms might be involved in resurgence.
A simple way to novel 2‐dichloromethyl‐5‐aryl‐2H‐tetrazoles
Authors: Mikolaichuk Olga V. , Batyrenko Alina A. , Kornyakov Ilya V. , Trifonov Rostislav E.
Published: January 2021

A series of 2‐dichloromethyl‐5‐aryl‐2H‐tetrazoles (3a–i) were synthesized by the reaction of 5‐aryl‐NH‐tetrazoles with trichloromethane in strong organic basic condition. The reaction represents a single‐stage access to a new class of promising compounds, which not only can have biological activity, but can also serve as intermediates for further alkylation of halogen and the introduction of various fragments into the structure. The compounds obtained were fully characterized by means of ESI–MS, 1H and 13C{1H} NMR spectroscopies, as well as by single‐crystal X‐ray diffraction (for 3b) the structural parameters as well as the vibrational corrections to enthalpies and total energies of the investigated systems were calculated using DFT B3LYP/6‐31+G** approach.
The effects of the COVID‐19 pandemic on risk management practice: A report from the epicenter of the epicenter in New York City
Authors: Tolentino Victorio R. , Derevlany Louise , DeLaMothe Cassandra , Vick Suzanne , Chalyavski Luba
Published: January 2021

Health care organizations have had to respond to the Coronavirus disease 2019 (COVID‐19) pandemic in unprecedented ways. In the United States, where health risk management is an established profession, health care risk managers (HRMs) contributed to the response by supporting organizations and frontline workers. HRMs advised administrative and clinical leadership on decisions and policies aimed at addressing the medico legal, ethical, and operational dilemmas raised by this public health emergency. This article describes these challenges from the perspective of a New York City (NYC) public hospital located in the “epicenter within the epicenter” of the pandemic and aims to provide practical guidance for HRMs on the front lines of this crisis.
Experience with PlasmaJet™ in debulking surgery in 87 patients with advanced‐stage ovarian cancer
Authors: Volcke Alexander , Van Nieuwenhuysen Els , Han Sileny , Salihi Rawand , Van Gorp Toon , Vergote Ignace
Published: January 2021

Objective

The aim was to evaluate the effectiveness and safety of PlasmaJet™ in cytoreductive surgery in patients with advanced‐stage ovarian cancer.

Methods

All patients between September 2013 and January 2018 undergoing surgical cytoreduction for advanced‐stage ovarian cancer with the help of PlasmaJet™ were identified and analyzed retrospectively.

Results

Eighty‐seven patients diagnosed with advanced‐stage ovarian cancer underwent surgery with PlasmaJet™. Primary debulking surgery was performed in 15 cases. Fifty‐seven patients underwent interval debulking after neoadjuvant chemotherapy. Secondary and tertiary debulking was done in, respectively, 11 and three patients, and one patient underwent quaternary debulking using PlasmaJet™. In all 87 patients but one, complete resection of all macroscopic disease was obtained. PlasmaJet™ was used to remove carcinomatosis on the peritoneum, bowel serosa, intestinal mesentery, and lesions in the upper abdomen (diaphragm and liver surface). No damage to the bladder or ureter was noted in relation to the use of PlasmaJet™. Three patients developed a bowel leakage postoperatively. In one of these patients, PlasmaJet™ was used to treat tumoral implants in the affected region.

Conclusions

Our series suggests that the use of PlasmaJet™ is efficient and safe in obtaining complete resection of all macroscopic tumoral lesions in advanced‐stage ovarian cancer.
Lung Ultrasound for Identification of Patients Requiring Invasive Mechanical Ventilation in COVID‐19
Authors: Seiler Claudia , Klingberg Cecilia , Hårdstedt Maria
Published: January 2021

Objectives

Indication for invasive mechanical ventilation in COVID‐19 pneumonia has been a major challenge. This study aimed to evaluate if lung ultrasound (LUS) can assist identification of requirement of invasive mechanical ventilation in moderate to severe COVID‐19 pneumonia.

Materials and Methods

Between April 23 and November 12, 2020, hospitalized patients with moderate to severe COVID‐19 (oxygen demand ≥4 L/min) were included consecutively. Lung ultrasound was performed daily until invasive mechanical ventilation (IMV‐group) or spontaneous recovery (non‐IMV‐group). Clinical parameters and lung ultrasound findings were compared between groups, at intubation (IMV‐group) and highest oxygen demand (non‐IMV‐group). A reference group with oxygen demand <4 L/min was examined at hospital admission.

Results

Altogether 72 patients were included: 50 study patients (IMV‐group, n = 23; non‐IMV‐group, n = 27) and 22 reference patients. LUS‐score correlated to oxygen demand (SpO2/FiO2‐ratio) (r = 0.728; p < .0001) and was higher in the IMV‐group compared to the non‐IMV‐group (20.0 versus 18.0; p = .026). Based on receiver operating characteristic analysis, a LUS‐score of 19.5 was identified as cut‐off for requirement of invasive mechanical ventilation (area under the curve 0.68; sensitivity 56%, specificity 74%). In 6 patients, LUS identified critical coexisting conditions. Respiratory rate and oxygenation index ((SpO2/FiO2)/respiratory rate) ≥4.88 identified no requirement of invasive mechanical ventilation with a positive predictive value of 87% and negative predictive value of 100%.

Conclusions

LUS‐score had only a moderate diagnostic value for requirement of invasive mechanical ventilation in moderate to severe COVID‐19. However, LUS proved valuable as complement to respiratory parameters in guidance of disease severity and identifying critical coexisting conditions.
Impacts of nitrogen enrichment on vegetation growth dynamics are regulated by grassland degradation status
Authors: Xu Xiaotian , Hu Guozheng , Liu Xu , Lu Shaowei , Li Shaoning , Zhao Na
Published: January 2021

Plant phenological responses under global climate change is a hot topic in current ecological research. However, it also has comprehensive interactions with other anthropogenic environmental factors including nitrogen (N) enrichment owing to atmospheric deposition and fertilization, and grassland degradation, which attracts less attention. Continuous photographic techniques enabled us to monitor the plant cover dynamics and extract the phenophases (start, end, length and the peak cover position of growing season) in a field experimental platform with six N treatment levels on five grasslands along a degradation gradient indicated by a human disturbance index (HDI). The results showed that N addition significantly promoted seasonal plant covers of degraded grasslands, while mature grassland responding less sensitively. Moreover, increasing rates during spring green‐up and decreasing rates during autumn senescence were promoted by N addition, while those of grasslands with lower degradation levels showed non‐linear saturation patterns. Phenophases at the community level were generally insensitive to N addition, with the most degraded grassland (totally degraded grassland, TD) and mature grassland (MG) responding significantly. The length of growing season of TD was shortened by 8 days and that of MG lengthened by 15 days on average from N addition. The responses of extracted phenophases were regulated more by the proportions of three groups of degradation indicators (annuals, moderate grazing degradation indicator species, and climax species) than those of grasses and forbs. Our findings highlight the relationship between community phenology and grassland degradation, which can benefit the assessment and restoration of degraded grasslands in semiarid regions.
Identification of dissolved organic matter size components in freshwater and marine environments
Authors: Asmala Eero , Massicotte Philippe , Carstensen Jacob
Published: January 2021

Dissolved organic matter (DOM) in the transition zone from freshwater to marine systems was analyzed with a new approach for parameterizing the size distribution of organic compounds. We used size‐exclusion chromatography for molecular size analysis and quantified colored DOM (CDOM) on samples from two coastal environments in the Baltic Sea (Roskilde Fjord, Denmark and Gulf of Gdansk, Poland). We applied a Gaussian decomposition method to identify peaks from the chromatograms, providing information beyond bulk size properties. This approach complements methods where DOM is separated into size classes with pre‐defined filtering cutoffs, or methods where chromatograms are used only to infer average molecular weight. With this decomposition method, we extracted between three and five peaks from each chromatogram and clustered these into three size groups. To test the applicability of our method, we linked our decomposed peaks with salinity, a major environmental driver in the freshwater‐marine continuum. Our results show that when moving from freshwater to low‐salinity coastal waters, the observed steep decrease of apparent molecular weight is mostly due to loss of the high‐molecular‐weight fraction (HMW; >2 kDa) of CDOM. Furthermore, most of the CDOM absorbance in freshwater originates from HMW DOM, whereas the absorbing moieties are more equally distributed along the smaller size range (< 2 kDa) in marine samples.
Elemental Sulfur Mediated Novel Multicomponent Redox Polycondensation for the Synthesis of Alternating Copolymers Based on 2,4‐Thiophene/Arene Repeating Units
Authors: Mutlu Hatice , Döpping Daniel A. , Huber Birgit , Theato Patrick
Published: January 2021

A sulfur‐based self‐condensation method is investigated as an efficient tool for the synthesis of polythiophene derivatives. The reaction proceeds through multicomponent redox polycondensation between readily available diketone compounds and elemental sulfur in the presence of a Brønsted acid/base pair. Six different diketone derivatives have been screened and the polymerization is generalized by the synthesis of so‐far‐unprecedented alternating copolymers based on 2,4‐thiophene/arene repeating units. By exploiting microwave heating the synthetic procedure is optimized, particularly for alternating copolymers containing aryl and thiophene units, such that a copolymer can be synthesized in only 24 h compared to the conventional process taking 6 d, yielding polymers within the same apparent weight average molar mass (Mw). All obtained copolymers are analyzed in detail using size exclusion chromatography (SEC), nuclear magnetic resonance (NMR), attenuated total reflectance infrared spectroscopy (ATR‐IR), thermal gravimetric analysis and differential scanning calorimetry (DSC).
Data envelopment analysis based assessment of human resource management strategy in the banking industry: A case study of a well‐known Taiwanese Bank
Authors: Lou Shi‐wan , Yang Yiwen , Tseng Chu‐wei
Published: January 2021

This study examines the efficiency in operating performances of domestic branches of a well‐known Taiwanese Bank by adopting a data envelopment analysis (DEA). The empirical findings show that most branches are gauged inefficiently. Some should strengthen professional training of managers to improve the pure technical efficiency; others should enhance the scale efficiency. In addition, based on the empirical results, strategies to improve the efficiency of human resources by allocating workforce are proposed. Appropriately adjusting the number of staffs among branches is an effective way to increase the operating performances of the bank.
Global attractors for a system of elasticity with small delays
Authors: Araújo Rawlilson O. , Bocanegra‐Rodríguez Lito E. , Calsavara Bianca M. R. , Seminario‐Huertas Paulo N. , Sotelo‐Pejerrey Alfredo
Published: January 2021

This paper is concerned with dynamics of elasticity systems featuring a nonlinear foundation of critical growth and delay effects. The existence of global attractors for such systems has been studied recently. Our main contribution establishes the upper‐semicontinuity of attractors with respect to a small parameter multiplying the delay term. Our results are new even for the analogous scalar wave equation.
Model‐Assisted Optimization of RAFT Polymerization in Micro‐Scale Reactors—A Fast Screening Approach
Authors: Kandelhard Felix , Schuldt Karina , Schymura Juliane , Georgopanos Prokopios , Abetz Volker
Published: January 2021

In this work, the combination of different modeling approaches with in‐line proton nuclear magnetic resonance (1H‐NMR) spectroscopy is used to assist the transfer of a reversible addition‐fragmentation chain transfer (RAFT) polymerization of methyl methacrylate to a micro‐scale reactor. This approach is then applied to find the optimal process parameters like temperature or residence time as well as the best composition of the reaction mixture in order to optimize the conversion and molecular characteristics of the synthesized polymer. A kinetic model based on ordinary differential equations implemented in the program Predici is first validated based on experimental data of reactions performed at various temperatures. Further on, two glass chip reactors and a coil reactor are used and combined in different ways to investigate the influence of the reactor geometry on the polymerization process. This optimization step is assisted by multiphysics modeling that focuses on the heat transfer properties of specific areas inside the reactors. This experimental setup is used successfully to carry out a stationary polymerization. This study shows that instationary experiments in a micro‐fluidic reactor system equipped with in‐line analytics allow for the fast development of a kinetic model for RAFT polymerizations.
Physicochemical properties and antimicrobial activity of nanocomposite films based on carboxymethylcellulose and silver nanoparticles
Authors: Yunusov Khaydar Ergashovich , Sarymsakov Abdushkur Abdukhalilovich , Jalilov Javlon Zafar o`g`li , Аtakhanov Abdumutallib Abdupatto o`g`li
Published: January 2021

Silver nanoparticles (AgNPs) stabilized by sodium carboxymethylcellulose (Na‐CMC) with degree of substitution (DS) 0.65‐0.90 and degree of polymerization (DP) 200‐600 were synthesized by photochemical method. The structural, physico‐chemical, and physico‐mechanical properties as well as antimicrobial activity of polymer films containing the Na‐CMC and AgNPs were studied. The shape, quantity, and size of the AgNPs embedded into the Na‐CMC films were determined by UV‐Vis spectroscopy, ZETASIZER Nano ZS, atomic force microscopy and transmission electron microscopy. It was found that the increase of silver nitrate concentration in solution of Na‐CMC followed by photoirradiation leads to the change of size and shape of AgNPs. The AgNPs in the range of size from 5 to 35 nm were found to enhance the microbicidal activities of the Na‐CMC films.
Schiff‐base‐functionalized polymeric hydrogel with high stretchability and multifunction
Authors: Liao Shanshan , Tang Liuyan , Qu Jinqing
Published: January 2021

Here we report a novel salicylaldehyde‐based Schiff‐base‐functionalized polymeric hydrogel (SSb‐hydrogel) with excellent stretchability, temperature responsiveness, self‐healing property, and adjustable fluorescence intensity. The SSb‐hydrogel was obtained by a one‐pot micellar copolymerization of acrylamide (AAm), N‐isopropylacrylamide (NIPAM), and a hydrophobic cross‐linking agent (AVIMP). The three‐dimensional network of SSb‐hydrogel was formed by the chemical cross‐linking of AVIMP and the hydrophobic interaction between AVIMP molecules. The SSb‐hydrogel was able to stretch up to 1900% of its original length without fracture, and its transparency was adjustable by temperature. This hydrogel also had tunable fluorescence controlled by Zn2+/EDTA, and its fluorescence increased by 640% with 0.1 M Zn2+. Its fluorescence property enabled us to write on its surface repeatedly. This highly stretchable and multifunctional SSb‐hydrogel has potential applications in temperature‐sensitive materials, information transmission, and soft sensors.
The effect of poly(acrylic acid) on temperature‐dependent behaviors and structural evolution of poloxamer 407
Authors: Hirun Namon , Tantishaiyakul Vimon , Sangfai Tanatchaporn , Boonlai Wannisa , Soontaranon Siriwat , Rugmai Supagorn
Published: January 2021

Understanding temperature‐dependent behaviors and structural evolution plays an essential role in the development of thermosensitive hydrogels. In this work, thermosensitive hydrogels composed of poly(acrylic acid) (PAA) and poloxamer 407 (PX) were investigated. The effect of PAA on the thermosensitive micellization, gelation and structural evolution of 20% PX (20PX) was studied by means of differential scanning calorimetry (DSC), rheology and small angle X‐ray scattering. In addition, the structural and amplitude‐dependent rheological characteristics of mixtures of 20PX and various concentrations of PAA (PAA/PX) gels at body temperature were also examined. The DSC thermograms of the PAA/PX mixtures revealed overlapping double endothermic peaks, reflecting the micellization of PX micelles with attached PAA and pure PX micelles. The formation of PX micelles with attached PAA increased when PAA concentration was increased. The intermicellar packing of PX micelles might be interfered by the attached PAA; the presence of PAA modulated the gelation temperature. All thermosensitive systems showed disorder‐to‐order structural evolution upon heating. Although the micelles in the plain 20PX gel arranged into a face‐centered cubic (FCC) geometry, a body‐centered cubic (BCC) phase emerged in the PAA/PX mixtures and became predominant with increasing PAA concentration. The presence of PAA chains tailored the ordered structure of the gels and favored the BCC arrangement.The rheological and ordered structural properties of the PAA/PX gels at body temperature can be modulated by varying the concentration of PAA. © 2021 Society of Chemical Industry
Advanced Electrical Conductors: An Overview and Prospects of Metal Nanocomposite and Nanocarbon Based Conductors
Authors: Tehrani Mehran
Published: January 2021

Advanced electrical conductors that outperform copper and aluminum can revolutionize our lives by enabling billions of dollars in energy savings and facilitating a transition to an electric mobility future. Nanocarbons (carbon nanotubes and graphene) present a unique opportunity for developing advanced conductors for electrical power, communications, electronics, and electric machines for the defense, energy, and automotive industries. Herein, the major research progress in the field of advanced nanocarbon‐based and metal–nanocarbon conductors is compiled. The benefits and drawbacks of advanced conductors are also elucidated with respect to conventional ones and their materials science, mechanical and physical properties, and characterization are discussed. Finally, several areas of future research for advanced electrical conductors are proposed.
Dynamic model and control for a cable‐driven continuum manipulator used for minimally invasive surgery
Authors: Qi Fei , Chen Bai , Gao Shuyuan , She Shigang
Published: January 2021

Background

Due to its unique flexible and dexterity, continuum robot has been widely used in small constrained environment. However, those advantages also bring that motion modelling and accurate control for the continuum robot is more complicated and tedious. A dynamic model and control strategy is presented for improving its control performance.

Methods

The kinematics and velocity model of the robot are derived. The inertial force, elastic force, gravity and actuation force applied to the continuum robot are analysed. Meanwhile, the friction in drive system is investigated, and dynamic model is established by the Kane's method. Finally, a motion control strategy is proposed based on this model to verify the dynamic model.

Results

Results of the simulation and experiment of a prototype verify the proposed model and its control method.

Conclusions

The proposed model and control strategy can be used to achieve the bending deformation of the robot.
Towards the Synthesis of Imidazopyridine Derivatives: Characterization, Single Crystal XRD, Hirshfeld Analysis, and Biological Evaluation
Authors: Kuthyala Sharanya , Sheikh Sareen , Nagaraja G. K. , Kannika B. R. , Madan Kumar S. , Chandra Nayak S. , Lokanath N. K.
Published: January 2021

This study explores the synthesis of different imidazopyridine derivatives, their characterization, single crystal x‐ray diffraction, molecular Hirshfeld surface analysis along with their anticancer and other supportive biological evaluations. X‐ray crystallography study resolved the crystal structure of 2,7‐dimethyl‐N‐(1,3‐dioxoisoindolin‐2‐yl)H‐imidazo[1,2‐a]pyridine‐3‐carboxamide (2 a) as monoclinic crystal system (space group P21/n). Graphical tool, Hirshfeld surface analysis quantified the major contribution of H⋅⋅⋅H, O⋅⋅⋅H, and C⋅⋅⋅H interactions towards the HS. Among the synthesized compounds, 2‐(4‐(4‐fluorophenyl)‐5‐(2,8‐dimethylH‐imidazo[1,2‐a]pyridin‐3‐yl)‐4H‐1,2,4‐triazol‐3‐ylthio)‐N‐(4‐fluorophenyl)acetamide (5 a) exhibited the highest cytotoxicity against lung adenocarcinoma with IC50 value of 43.04 μM. Selective action of 5 a was assured by cell death analysis using AO‐EB assay. In addition, the study was also supported by molecular docking studies. Together the study revealed, the compound 5 a, to be a likely candidate for further exploratory study in cancer treatment.
Recent Progress in Iodine‐Catalysed C−O/C−N Bond Formation of 1,3‐Oxazoles: A Comprehensive Review
Authors: Dhawan Sanjeev , Kumar Vishal , Girase Pankaj S. , Mokoena Sithabile , Karpoormath Rajshekhar
Published: January 2021

Over the last few decades, iodine has been a stellar catalyst for numerous organic transformations such as C−H activation, hetero‐annulation and coupling reactions. In heterocyclic chemistry, iodine is primarily an economical and eco‐friendly catalyst that fascinates the construction of C−O/C−N bonds via oxidative, radical, and electrophilic pathways. Several novel Iodine‐catalyzed methodologies have been reported, presenting advances in heterocyclic synthesis with regioselectivity, wide substrate scope and excellent yields. Furthermore, feasible protocols implemented to get oxazole annulation in literature have an enormous impact on new synthetic applications. Therefore, this literature analysis comprises advancements in the field of iodine‐mediated 1,3‐oxazole synthesis since 1998. For the ease of the readers, the reported methodologies have been categorised based on iodine functioning in reactions with insight into the reaction mechanisms and highlights.
Chan−Lam Arylation of Benzimidazole and its Derivatives in the Presence of Copper‐Containing Minerals
Authors: Györke Gábor , Dancsó András , Volk Balázs , Milen Mátyás
Published: January 2021

Copper catalysis plays a remarkable role in synthetic organic chemistry. The catalytic activity of copper‐containing minerals is not sufficiently presented in the literature, even though the economical value of such procedures is rather high. With the direct usage of these readily available ores, the highly polluting industrial copper production can be avoided. In the present work, the copper‐containing mineral catalyzed Chan−Lam reaction of benzimidazole, substituted benzimidazoles or imidazole with various phenylboronic acids is described. A total of nine readily available ores were tested in our model reaction with bornite (Cu5FeS4) and chalcocite (Cu2S) being the best among them. The in situ formed catalytic system of Cu5FeS4/TMEDA was able to produce the desired products in up to 98 % yields and it was reusable making this process even more economical and environmentally friendly.