bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantitative analyses reveal extracellular dynamics of Wnt ligands in Xenopus embryos
Authors: Mii Yusuke , Nakazato Kenichi , Pack Chan-Gi , Ikeda Takafumi , Sako Yasushi , Mochizuki Atsushi , Taira Masanori , Takada Shinji
Published: April 2021

The mechanism of intercellular transport of Wnt ligands is still a matter of debate. To better understand this issue, we examined the distribution and dynamics of Wnt8 inXenopusembryos. While Venus-tagged Wnt8 was found on the surfaces of cells close to Wnt-producing cells, we also detected its dispersal over distances of 15 cell diameters. A combination of fluorescence correlation spectroscopy and quantitative imaging suggested that only a small proportion of Wnt8 ligands diffuses freely, whereas most Wnt8 molecules are bound to cell surfaces. Fluorescence decay after photoconversion showed that Wnt8 ligands bound on cell surfaces decrease exponentially, suggesting a dynamic exchange of bound forms of Wnt ligands. Mathematical modeling based on this exchange recapitulates a graded distribution of bound, but not free, Wnt ligands. Based on these results, we propose that Wnt distribution in tissues is controlled by a dynamic exchange of its abundant bound and rare free populations.
Chloroplast acquisition without the gene transfer in kleptoplastic sea slugs, Plakobranchus ocellatus
Authors: Maeda Taro , Takahashi Shunichi , Yoshida Takao , Shimamura Shigeru , Takaki Yoshihiro , Nagai Yukiko , Toyoda Atsushi , Suzuki Yutaka , Arimoto Asuka , Ishii Hisaki , Satoh Nori , Nishiyama Tomoaki , Hasebe Mitsuyasu , Maruyama Tadashi , Minagawa Jun , Obokata Junichi , Shigenobu Shuji
Published: April 2021

Some sea slugs sequester chloroplasts from algal food in their intestinal cells and photosynthesize for months. This phenomenon, kleptoplasty, poses a question of how the chloroplast retains its activity without the algal nucleus. There have been debates on the horizontal transfer of algal genes to the animal nucleus. To settle the arguments, this study reported the genome of a kleptoplastic sea slug, Plakobranchus ocellatus, and found no evidence of photosynthetic genes encoded on the nucleus. Nevertheless, it was confirmed that light illumination prolongs the life of mollusk under starvation. These data presented a paradigm that a complex adaptive trait, as typified by photosynthesis, can be transferred between eukaryotic kingdoms by a unique organelle transmission without nuclear gene transfer. Our phylogenomic analysis showed that genes for proteolysis and immunity undergo gene expansion and are up-regulated in chloroplast-enriched tissue, suggesting that these molluskan genes are involved in the phenotype acquisition without horizontal gene transfer.
A robust method for particulate detection of a genetic tag for 3D electron microscopy
Authors: Rae James , Ferguson Charles , Ariotti Nicholas , Webb Richard I , Cheng Han-Hao , Mead James L , Riches James D , Hunter Dominic JB , Martel Nick , Baltos Joanne , Christopoulos Arthur , Bryce Nicole S , Cagigas Maria Lastra , Fonseka Sachini , Sayre Marcel E , Hardeman Edna C , Gunning Peter W , Gambin Yann , Hall Thomas E , Parton Robert G
Published: April 2021

Genetic tags allow rapid localization of tagged proteins in cells and tissues. APEX, an ascorbate peroxidase, has proven to be one of the most versatile and robust genetic tags for ultrastructural localization by electron microscopy (EM). Here, we describe a simple method, APEX-Gold, which converts the diffuse oxidized diaminobenzidine reaction product of APEX into a silver/gold particle akin to that used for immunogold labelling. The method increases the signal-to-noise ratio for EM detection, providing unambiguous detection of the tagged protein, and creates a readily quantifiable particulate signal. We demonstrate the wide applicability of this method for detection of membrane proteins, cytoplasmic proteins, and cytoskeletal proteins. The method can be combined with different EM techniques including fast freezing and freeze substitution, focussed ion beam scanning EM, and electron tomography. Quantitation of expressed APEX-fusion proteins is achievable using membrane vesicles generated by a cell-free expression system. These membrane vesicles possess a defined quantum of signal, which can act as an internal standard for determination of the absolute density of expressed APEX-fusion proteins. Detection of fusion proteins expressed at low levels in cells from CRISPR-edited mice demonstrates the high sensitivity of the APEX-Gold method.
Widespread premature transcription termination of Arabidopsis thaliana NLR genes by the spen protein FPA
Authors: Parker Matthew T , Knop Katarzyna , Zacharaki Vasiliki , Sherwood Anna V , Tomé Daniel , Yu Xuhong , Martin Pascal GP , Beynon Jim , Michaels Scott D , Barton Geoffrey J , Simpson Gordon G
Published: April 2021

Genes involved in disease resistance are some of the fastest evolving and most diverse components of genomes. Large numbers of nucleotide-binding, leucine-rich repeat (NLR) genes are found in plant genomes and are required for disease resistance. However, NLRs can trigger autoimmunity, disrupt beneficial microbiota or reduce fitness. It is therefore crucial to understand how NLRs are controlled. Here, we show that the RNA-binding protein FPA mediates widespread premature cleavage and polyadenylation of NLR transcripts, thereby controlling their functional expression and impacting immunity. Using long-read Nanopore direct RNA sequencing, we resolved the complexity of NLR transcript processing and gene annotation. Our results uncover a co-transcriptional layer of NLR control with implications for understanding the regulatory and evolutionary dynamics of NLRs in the immune responses of plants.
Mechanistic theory predicts the effects of temperature and humidity on inactivation of SARS-CoV-2 and other enveloped viruses
Authors: Morris Dylan H , Yinda Kwe Claude , Gamble Amandine , Rossine Fernando W , Huang Qishen , Bushmaker Trenton , Fischer Robert J , Matson M Jeremiah , Van Doremalen Neeltje , Vikesland Peter J , Marr Linsey C , Munster Vincent J , Lloyd-Smith James O
Published: April 2021

Ambient temperature and humidity strongly affect inactivation rates of enveloped viruses, but a mechanistic, quantitative theory of these effects has been elusive. We measure the stability of SARS-CoV-2 on an inert surface at nine temperature and humidity conditions and develop a mechanistic model to explain and predict how temperature and humidity alter virus inactivation. We find SARS-CoV-2 survives longest at low temperatures and extreme relative humidities (RH); median estimated virus half-life is >24 hr at 10°C and 40% RH, but ∼1.5 hr at 27°C and 65% RH. Our mechanistic model uses fundamental chemistry to explain why inactivation rate increases with increased temperature and shows a U-shaped dependence on RH. The model accurately predicts existing measurements of five different human coronaviruses, suggesting that shared mechanisms may affect stability for many viruses. The results indicate scenarios of high transmission risk, point to mitigation strategies, and advance the mechanistic study of virus transmission.
DXA reference values of the humanoid sheep model in preclinical studies
Authors: Biehl Christoph , Schmitt Jakob , Stoetzel Sabine , Malhan Deeksha , Hassan Fathi , Knapp Gero , Heiss Christian , El Khassawna Thaqif
Published: April 2021

Background

Merino land sheep are a popular pre-clinical large animal model in research on systemic skeletal diseases such as osteoporosis. Interpretation of studies is difficult because many reference parameters are missing or not established. This study aims to determine the reference parameters of the skeletal system (peak bone mass = PBM, T-Score). A defined standard allows an easier comparison of the study data of the animal model with human studies (T-Score).

Materials and methods

A total of 116 Dual Energy X-ray Absorptiometry DXA measurements were performed on 74 untreated sheep. The average age of the animals was 57 months. The BMD, BMC, and fat content of the sheep were determined by the relevant human region of interest (ROI). From this, the PBM and from this the T-score for each of the animals were calculated.

Results

Using 682 DXA measurements BMD and BMC were determined to provide an indication to PBM. For BMD a significant correlation to the age of the animals was observed (p = 0.043). A significant correlation was also seen for BMC (B) (p ≤ 0.001). In the age-dependent analysis, a widespread of values above the linear regression line was measured for both BMD and BMC between the 50th and 90th months of life. From an age of about 90 months, a wider spread of values below the linear regression line was found, although the average values continued to rise.

Discussion

The evaluation of the 116 DXA measurements allowed the determination of the PBM for merino land sheep. With the help of the PBM, a T-score was calculated for each animal. The statistical analysis shows significant differences in BMD values between the different animal groups in each of the four ROIs investigated. Individual control or sham groups per study are therefore not sufficient. To improve comparability, an independent reference group should be established.

Conclusion

An independent reference group for PBM and a T-score was established from four to six-year-old animals. The bone density increases with the age of the animals. Around the fourth year of life, a first peak could be observed. Also, after the seventh year of life, a further peak with the beginning plateau phase was observed. When compiling a group of animals for an osteoporosis model, animals from the age of seven years should, therefore, be used.
A Toll-like receptor identified in Gigantidas platifrons and its potential role in the immune recognition of endosymbiotic methane oxidation bacteria
Authors: Li Mengna , Chen Hao , Wang Minxiao , Zhong Zhaoshan , Wang Hao , Zhou Li , Zhang Huan , Li Chaolun
Published: April 2021

Symbiosis with chemosynthetic bacteria is an important ecological strategy for the deep-sea megafaunas including mollusks, tubeworms and crustacean to obtain nutrients in hydrothermal vents and cold seeps. How the megafaunas recognize symbionts and establish the symbiosis has attracted much attention. Bathymodiolinae mussels are endemic species in both hydrothermal vents and cold seeps while the immune recognition mechanism underlying the symbiosis is not well understood due to the nonculturable symbionts. In previous study, a lipopolysaccharide (LPS) pull-down assay was conducted in Gigantidas platifrons to screen the pattern recognition receptors potentially involved in the recognition of symbiotic methane-oxidizing bacteria (MOB). Consequently, a total of 208 proteins including GpTLR13 were identified. Here the molecular structure, expression pattern and immune function of GpTLR13 were further analyzed. It was found that GpTLR13 could bind intensively with the lipid A structure of LPS through surface plasmon resonance analysis. The expression alternations of GpTLR13 transcripts during a 28-day of symbiont-depletion assay were investigated by real-time qPCR. As a result, a robust decrease of GpTLR13 transcripts was observed accompanying with the loss of symbionts, implying its participation in symbiosis. In addition, GpTLR13 transcripts were found expressed exclusively in the bacteriocytes of gills of G. platifrons by in situ hybridization. It was therefore speculated that GpTLR13 may be involved in the immune recognition of symbiotic methane-oxidizing bacteria by specifically recognizing the lipid A structure of LPS. However, the interaction between GpTLR13 and symbiotic MOB was failed to be addressed due to the nonculturable symbionts. Nevertheless, the present result has provided with a promising candidate as well as a new approach for the identification of symbiont-related genes in Bathymodiolinae mussels.
Identification of potential genes in upper tract urothelial carcinoma using next-generation sequencing with bioinformatics and in vitro analyses
Authors: Lee Hsiang-Ying , Li Ching-Chia , Li Wei-Ming , Hsu Ya-Ling , Yeh Hsin-Chih , Ke Hung-Lung , Yeh Bi Wen , Huang Chun-Nung , Li Chien-Feng , Kuo Po-Lin , Wu Wen-Jeng
Published: April 2021

Background

We aimed to identify prognostic biomarkers of upper tract urothelial carcinomas (UTUCs), including microRNAs (miRNAs) and genes which account for only 5% to 10% of all urothelial carcinomas (UCs). In Taiwan, this figure is markedly higher, where it can reach up to 30% of UC cases.

Materials and Methods

Using next-generation sequencing (NGS), we analyzed two pairs of renal pelvis tumors and adjacent normal urothelial tissues to screen miRNAs and messenger RNAs. By combining bioinformatics analysis from miRmap, Gene Expression Omnibus (GEO), and Oncomine and Ingenuity® Pathway Analysis databases, we identified candidate genes. To search for upstream miRNAs with exact target binding sites, we used miRmap, TargetScan, and miRDB to enforce evidence. Then, we clarified gene and protein expression through an in vitro study using western blot analysis and quantitative real-time reverse transcriptase-PCR.

Results

Interactions between selected target genes obtained using the NGS and miRmap methods were assessed through a Venn diagram analysis. Six potential genes, namely, PDE5A, RECK, ZEB2, NCALD, PLCXD3 and CYBRD1 showed significant differences. Further analysis of gene expression from the GEO dataset indicated lower expression of PDE5A, RECK, ZEB2, and CYBRD1 in bladder cancer tissue than in normal bladder mucosa, which indicated that PDE5A, RECK, ZEB2, and CYBRD1 may act as tumor suppressors in UTUC. In addition, we compared the expression of these genes in various UC cell lines (RT4, BFTC905, J82, T24, UMUC3, 5637, BFTC 909, UMUC14) and found decreased expression of PDE5A in muscle-invasive UC cells compared with the RT4 cell line. Furthermore, by using paired UTUC and normal tissues from 20 patients, lower PDE5A expression was also demonstrated in tumor specimens.

Conclusions

Our findings suggest these candidate genes may play some roles in UTUC progression. We propose that these markers may be potential targets clarified by in vitro and in vivo experiments. PDE5A also potentially presents tumor suppressor genes, as identified by comparing the expression between normal and tumor specimens.
Genome-wide identification and expression analysis of the trehalose-6-phosphate synthase (TPS) gene family in cucumber (Cucumis sativus L.)
Authors: Dan Yuanyuan , Niu Yuan , Wang Chunlei , Yan Mei , Liao Weibiao
Published: April 2021

Trehalose-6-phosphate synthase (TPS) is significant in the growth, development and stress resistance of plants. We identified the cucumber TPS family and its physicochemical properties, domains, gene structures, evolutionary relationships, gene locations, cis-acting elements, conserved motifs, and expression patterns using bioinformatics. Our results uncovered seven CsTPS genes in the cucumber genome and named CsTPS1–CsTPS7 according to their locations in the chromosomes. Seven CsTPS genes were randomly distributed in six cucumber chromosomes. Domain analysis showed that the TPS and TPP domains exist in all CsTPSs, and an additional hydrolase-3 domain exist in CsTPS3, CsTPS5 and CsTPS6. Phylogenetic analysis showed that TPS proteins from Arabidopsis, rice, soybean, and cucumber were divided into two subfamilies (Class I and Class II) and they were further divided into seven subgroups. TPS proteins from Arabidopsis and cucumber were grouped together, suggesting a close evolutionary relationship. Gene structure analysis indicated that most Class I genes contained 16–17 introns, while Class II genes (except CsTPS7) had two introns. Motif analysis showed that Class II genes had 10 complete conserved motifs, while Class I genes lacked motif 8 and motif 9. Furthermore, CsTPS genes possessed numerous cis-acting elements related to stress, hormone, and light response in the promoter regions. GO analysis indicated multiple functions for the CsTPS proteins. Expression analysis of CsTPS genes in different tissues found that they were expressed in roots, stems and leaves, with the highest expression levels in roots. The expression analysis of CsTPSs under different treatments showed that CsTPS genes may participate in the response to abiotic stress, plant hormones and sugar treatments.
Impact of Soil Rejuvenating Scheme on Income of Cotton Farmers – An Evidence from Kalaburagi District of Karnataka
Authors: Sagar . , Khan Murtuza , Sharif Mahin
Published: April 2021

Rainfed areas are not only thirsty but also hungry for nutrients and are hotspots of poverty, malnutrition, and degradation of natural resources. Looking into these aspects, the Government of Karnataka has implemented a mission mode project called “Bhoochetana” meaning “reviving the soils” to benefit dryland farmers for sustainable use of natural resources in Karnataka. This scheme aimed at enhancing the yield level of major dryland crops through integrated crop management (ICM) practices. The study has been conducted in the Kalaburagi District of Karnataka State, where the majority of the area under agriculture is rainfed and cotton is one of the major rainfed crops grown on a large scale. The study revealed that the yield of the main product from cotton production for Bhoochetana beneficiary farmers was higher with 23.18 quintals per hectare compared to non-beneficiary farmers with 21.36 quintals. The results of partial budgeting showed that, a net gain of ₹ 4660 per hectare was obtained by Bhoochetana scheme beneficiaries over non-beneficiary farmers. The study highlighted that, there is a positive significant effect of the scheme on the production of cotton. Therefore, the policies must focus on long-term soil, water, and other natural resource conservation practices to achieve sustainability in agriculture.
Modeling the Effect of Inpatient Rehabilitation of Tobacco Smokers on Smoking Dynamics
Authors: Nyamai Amos Mwendwa , Mutuku Winifred N.
Published: April 2021

Aims:

Develop and analyze a mathematical model of the effect of inpatient rehabilitation of tobacco smokers on tobacco smoking using Kenya as a case study.

Perform stability analysis on the smoking free equilibrium point and endemic equilibrium point of the model.

Use numerical simulation to investigate the impact of inpatient rehabilitation of tobacco smokers on smoking.

Place and Duration of Study: Department of Mathematics and Actuarial Science, School of Pure and Applied Sciences (SPAS), Kenyatta University, Kenya, between May 2019 and September 2020.

Tobacco smoking is a serious burden in Kenya and the world at large. Smoking harms nearly every organ of the body and affects the overall health of a person. Despite the overwhelming facts about the consequences of tobacco smoking, it remains a bad wont which is socially accepted and widely spread. In this research we numerically analyze the dynamics of smoking incorporating the impact of inpatient rehabilitation to curb the smoking habit. We first present a three-compartment model incorporating inpatient rehabilitation, then develop the system of ordinary differential equations governing the smoking dynamics. The basic reproduction number is determined using next generation matrix method. The model equilibria were computed and the stability analysis carried out. The results of stability analysis indicate that the disease-free equilibrium (DFE) is both locally and globally asymptotically stable for RS < 1 while the endemic equilibrium is both locally and globally asymptotically stable for RS > 1. Numerical simulations of model carried out with the help of MATLAB shows that, when rehabilitation is implemented effectively, it helps in minimization of smoking in the community.
Clinical and Biochemical Predictors of Endothelial Dysfunction in Egyptian Adolescents with Type 1 and those with Type 2 Diabetes
Authors: Zakaria EkramHamed , Ghazy MedhatAbdElmaged , Mohamed Wesam Salah , Kotb Nesreen Ahmed
Published: April 2021

Aims: Since endothelial dysfunction precedes clinically significant diabetic vascular complications, circulating endothelial progenitor cells (EPCs) have generated interest as a biomarker of endothelial function and are considered a mirror for endogenous vasculo-regenerative capacity. So we aimed to assess EPCs count in adolescents with type 1 diabetes mellitus (T1DM) in comparison to those with type 2 diabetes mellitus (T2DM) and extend these findings to assess their relationship to other clinical and biochemical risks of endothelial dysfunction.

Patients and Methods: Fifty Egyptian adolescents were included in this study, 20 with T1DM, 20 T2DM and 10 healthy control subjects. Patients are recruited from Diabetes and Endocrinology Unit, outpatient clinic of internal medicine department Tanta University Hospital, in the period from 2017 to 2019. EPCs count was determined by Flowcytometry, anthropometric measurements and laboratory investigations were done for fasting and 2-hours post-prandial blood glucose, serum lipid profile, HbA1c, urinary albumin creatinine ratio, fasting C peptide, and homoeostasis model assessment of insulin resistance (HOMA- IR).

Results: In T1DM, EPCs count was significantly higher compared to T2DM(0.032) and control group(p0.001) and it was negatively correlated with age of patients and duration of diabetes but was positively correlated with HbA1c. While, the count was higher in T2DM compared to control with no statistically significant difference(p0.063) and negatively correlated with body mass index, waist circumference, blood pressure and HOMA-IR.

Conclusion: Adolescents with T2DM have distressing clinical and biochemical findings and significantly lower count of (EPCs) than adolescents with T1DM. This puts them at potential higher risk for early development of endothelial dysfunction and less power of vascular repair that may potentiate early harboring of vascular complications.
Perancangan Boks Truk Pengangkut Buah-Buahan
Authors: Santoso Johan K. , Suprianto Fandi Dwiputra
Published: April 2021

Adanya permintaan buah stroberi segar yang terus meningkat untuk kebutuhan dalam negeri maupun luar negeri mendorong penggunaan boks pendingin pada proses transportasi. Selain pendinginan, juga diperlukan humidifikasi ruangan agar buah stroberi dapat sampai dengan kondisi masih segar. Dalam perancangan ini, boks pendingin di desain agar mampu mempertahankan suhu 10℃ dan 90% RH. Untuk dapat mencapai suhu tersebut dilakukan perhitungan untuk mengetahui beban pendinginan dan diperlukan simulasi untuk melihat pengaturan penyusunan boks buah agar udara dapat tersebar secara merata. Setelah proses simulasi dan perhitungan teleh diselesaikan, didapatkan bahwa sistem pendingin boks truk yang dikeluarkan oleh produsen Denso mampu mencapai kondisi steady dalam waktu 10 menit dan dapat mencukupi kebutuhan untuk pendinginan ruangan meskipun sudah terbeban oleh komoditas dan humidifikasi ruangan. Sedangkan untuk susunan boks buah yang dipakai adalah disusun ke atas sebanyak 5 boks, 3 ke belakang, dan 3 ke samping untuk 1 buah pallete
Personalized Radiation Attenuating Materials for Gastrointestinal Mucosal Protection
Authors: Byrne James D. , Young Cameron C. , Chu Jacqueline N. , Pursley Jennifer , Chen Mu Xian , Wentworth Adam J. , Feng Annie , Kirtane Ameya R. , Remillard Kyla A. , Hancox Cindy I. , Bhagwat Mandar S. , Machado Nicole , Hua Tiffany , Tamang Siddartha M. , Collins Joy E. , Ishida Keiko , Hayward Alison , Becker Sarah L. , Edgington Samantha K. , Schoenfeld Jonathan D. , Jeck William R. , Hur Chin , Traverso Giovanni
Published: April 2021

Cancer patients undergoing therapeutic radiation routinely develop injury of the adjacent gastrointestinal (GI) tract mucosa due to treatment. To reduce radiation dose to critical GI structures including the rectum and oral mucosa, 3D‐printed GI radioprotective devices composed of high‐Z materials are generated from patient CT scans. In a radiation proctitis rat model, a significant reduction in crypt injury is demonstrated with the device compared to without (p < 0.0087). Optimal device placement for radiation attenuation is further confirmed in a swine model. Dosimetric modeling in oral cavity cancer patients demonstrates a 30% radiation dose reduction to the normal buccal mucosa and a 15.2% dose reduction in the rectum for prostate cancer patients with the radioprotectant material in place compared to without. Finally, it is found that the rectal radioprotectant device is more cost‐effective compared to a hydrogel rectal spacer. Taken together, these data suggest that personalized radioprotectant devices may be used to reduce GI tissue injury in cancer patients undergoing therapeutic radiation.
Hydrothermal Synthesis of Zinc‐Doped Silica Nanospheres Simultaneously Featuring Stable Fluorescence and Long‐Lived Room‐Temperature Phosphorescence
Authors: Cui Mingyue , Li Manjing , Wang Jinhua , Chen Runzhi , Xu Zhaojian , Wang Jingyang , Han Junfei , Hu Guyue , Sun Rong , Jiang Xin , Song Bin , He Yao
Published: April 2021

Fluorescence and phosphorescence are known as two kinds of fundamental optical signals, which have been used for myriad applications. To date, simultaneous activation of stable fluorescence and long‐lived room‐temperature phosphorescence (RTP) emission in the aqueous phase remains a big challenge. We prepare zinc‐doped silica nanospheres (Zn@SiNSs) with fluorescence and RTP properties using a facile hydrothermal synthetic strategy. For the as‐prepared Zn@SiNSs, the recombination of electrons and holes in defects and defect‐stabilized excitons derived from oxygen vacancy/C=N bonds lead to the production of stable fluorescence and long‐lived RTP (emission lasting for ≈9 s, quantum yield (QY): ≈33.6 %, RTP lifetime: ≈236 ms). The internal Si−O bonded networks and hydrophilic surface in Zn@SiNSs can reduce nonradiative decay to form self‐protective RTP, and also provide high water solubility, excellent pH‐ and photostability.
CeCl3/n‐BuLi: Enträtselung von Imamotos Organocer‐Reagenz
Authors: Berger Tassilo , Lebon Jakob , Maichle‐Mössmer Cäcilia , Anwander Reiner
Published: April 2021

CeCl3(thf) reagiert bei niedrigen Temperaturen mit MeLi, t‐BuLi und n‐BuLi zu isolierbaren Organocer‐Komplexen. Eine lösemittelabhängige, z. T. stark ausgeprägte Dissoziation von n‐BuLi konnte durch7Li‐NMR‐Spektroskopie aufgeklärt werden. Dieses Verhalten deutet darauf hin, dass “Ce(n‐Bu)3(thf)x” oder Solvens‐separierte Ionenpaare wie “[Li(thf)4][Ce(n‐Bu)4(thf)y]” die dominanten Spezies des Imamoto‐Reagenzes sind. Die Stabilität der Komplexe Li3Ln(n‐Bu)6(thf)4steigt mit der Abnahme der LnIII‐Größe deutlich. Untersuchungen zum Lösungsverhalten von kristallinem Li3Lu(n‐Bu)6(thf)4und Mischungen von LuCl3(thf)2/n‐BuLi in THF deuten darauf hin, dass eine merkliche Dissoziation von n‐BuLi nur bei Molverhältnissen von <1:3 erfolgt. Der an n‐BuLi abgereicherte Komplex LiLu(n‐Bu)3Cl(tmeda)2wurde durch Behandlung von Li2Lu(n‐Bu)5(tmeda)2mit ClSiMe3gewonnen, jedoch auf Kosten einer Einlagerung von LiCl. Imamotos Transformation von Ketonen zu tertiären Alkoholen wurde mit 1,3‐Diphenylpropan‐2‐on untersucht und lieferte 99 % des Alkohols.
Precise Identification and Characterization of Catalytically Active Sites on the Surface of γ‐Alumina**
Authors: Khivantsev Konstantin , Jaegers Nicholas R. , Kwak Ja‐Hun , Szanyi Janos , Kovarik Libor
Published: April 2021

γ‐alumina is one of the oldest and most important commercial catalytic materials with high surface area and stability. These attributes enabled its use as the first commercial large‐scale heterogeneous catalyst for ethanol dehydration. Despite progress in materials characterization the nature of the specific sites on the surface of γ‐alumina that are responsible for its unique catalytic properties has remained obscure and controversial. By using combined infrared spectroscopy, electron microscopy and solid‐state nuclear magnetic resonance measurements we identify the octahedral, amphoteric (O)5Al(VI)‐OH sites on the (100) segments of massively restructured (110) facets on typical rhombus‐platelet γ‐alumina as well as the (100) segments of irrational surfaces (invariably always present in all γ‐alumina samples) responsible for its unique catalytic activity. Such (O)5Al(VI)‐OH sites are also present on the macroscopically defined (100) facets of γ‐alumina with elongated/rod‐like geometry. The mechanism by which these sites lose ‐OH groups upon thermal dehydroxylation resulting in coordinatively unsaturated penta‐coordinate Al+3O5 sites is clarified. These coordinatively unsaturated penta‐coordinate Al sites produce well‐defined thermally stable Al‐carbonyl complexes. Our findings contribute to the understanding of the nature of coordinatively unsaturated Al sites on the surface of γ‐alumina and their role as catalytically active sites.
Further exploration of the reaction between cis‐[Fe(CO)4I2] and alkylamines: An aminium salt of fac‐[Fe(CO)3I3]− or an amine‐bound complex of fac‐[Fe(CO)3I2(NH2R)]?
Authors: Guo Jinzhong , Guo Zhuming , Xiao Zhiyin , Jin Jing , Yang Xiuqin , He Yi , Liu Xiaoming
Published: April 2021

Four new monoiron (II) tricarbonyl complexes with the amine bound, fac‐[Fe(CO)3I2(NH2R)] (R = Et, 1; nPr, 2; nBu, 3; nPent, 4), were reported using cis‐[Fe(CO)4I2] as the precursor. All the complexes 1–4 were structurally confirmed by various techniques such as ultraviolet–visible (UV–vis), Fourier transform infrared (FTIR), and nuclear magnetic resonance (NMR) spectra and elemental analysis of which complexes 1 and 2 are crystallographically determined. The reaction of the precursor with alkylamines proceeded in two main parallel pathways to form both aminium salts of fac‐[Fe(CO)3I3]− and the amine‐bound complexes (1–4). Their dominances altered with the reaction time. These complexes in DMSO undergo quick decomposition with complex 1 as the relatively most stable one (t1/2 = 7.3 min) although they are stable in solid status. Unlike the triiodo anion and pyridinyl analogs showing severe cytotoxicity due to the generation of iodine radical during the decomposition, no iodine radicals were detected from the fac‐[Fe(CO)3I2(NH2R)] complexes. Therefore, the cell viability of RT112 cells was not affected by the presence of the amine‐bound iron complex (1) up to 100 μmol L−1.
Effect of different drying methods on zein‐based microcapsules loaded with Artemisia argyis essence obtained by anti‐solvent precipitation
Authors: Xu Qunna , Bai Zhongxue , Ma Jianzhong , Huang Mengchen , Li Jiaojiao
Published: April 2021

Microencapsulation is considered an efficient technique to protect functional materials from oxidization while enabling controlled release. In this study, anti‐solvent precipitation was used to prepare zein‐based microcapsules loaded with Artemisia argyis essence (AAE@ZMs). The impact of different drying methods, namely vacuum drying, freeze drying, and spray drying on AAE@ZMs was evaluated. Quality of AAE@ZMs was evaluated by the determination of color, moisture content, bulk density, chemical structure, and morphology evaluation. Freeze dried AAE@ZMs (F‐AAE@ZMs) and vacuum dried microcapsules (V‐AAE@ZMs) respectively showed stronger water and oil absorption capacities. The residual content of Artemisia argyis essence (AAE) in V‐AAE@ZMs was higher than those in F‐AAE@ZMs and spray dried microcapsules (S‐AAE@ZMs) after continuously releasing for 120 h. Meanwhile, heated from 30 to 600°C, the residues of V‐AAE@ZMs and F‐AAE@ZMs were lower than those of S‐AAE@ZMs. Therefore, drying methods greatly affected key quality parameters of AAE@ZMs. This study provides guidance on the use of drying methods in microcapsules delivery systems with zein or other materials.
Who gains and who loses? Sociodemographic disparities in access to special education services among autistic students
Authors: Sturm Alexandra , Williams Justin , Kasari Connie
Published: April 2021

Little is known about differences in the allocation of special education services to students with autism compared with students with other primary learning differences (e.g., intellectual disability [ID], specific learning disability [SLD]) and the comparative impact of sociodemographic factors on special education service receipt. The present study aimed to compare allocation of services (i.e., quantity and types) between students eligible for special education services under autism, SLD and ID, and to identify differences in sociodemographic predictors (e.g., race, neighborhood income) of service allocation. Data were culled from special education administrative records from a large urban, primarily Hispanic, Latino, or Spanish‐serving school district from academic years 2011–2012 to 2016–2017. Participants included N = 76,428 students (Nautism = 18,151, NSLD = 54,001, NID = 4,276) ages 2–18. Results showed that autistic students received, on average, more services than students with SLD. Services received by students served under autism and SLD eligibility were more congruent with areas of need (e.g., language, occupational therapy) relative to students served under ID. Student‐level socioeconomic status (free and reduced lunch) was more positively predictive of the number of special education services received than the neighborhood income of the school the student attended. Finally, the most significant racial disparities in service allocation were observed among students served under autism eligibility. The present study demonstrates the critical role of economic resources in the quantity and types of services received, and the desirability of a public education for well‐resourced families who are possibly best situated to navigate special education services.

Lay Summary

An eligibility of autism in special education confers a significant advantage in the number of services a student receives. Disparity in the quantity of special education services exists among autistic students across many sociodemographic factors. Most notably, greater allocation of services to non‐Hispanic, Latino, or Spanish, White American, European American, or Middle Eastern American students and students who do not receive free and reduced lunch.
Overview on the current practices and future potential of bioenergy use in Palestine
Authors: Salah Wael A. , Abuhelwa Mai , Bashir Mohammed J.K.
Published: April 2021

Palestine has considerable potential for bioenergy production, which can contribute to the independence of the nation's energy sector. However, few projects have been implemented for the production and utilization of bioenergy. In this study, the potential effects of using bioenergy from various sources, such as municipal solid waste, wastewater treatment plants, and animal farms are studied. Certain studies and successful projects in Palestine are evaluated. Different technologies that could be used effectively are introduced. The challenges facing the adoption of bioenergy are discussed. The effect of energy generation is studied, and an economic analysis is performed. Results show that if bioenergy is adopted in the cities of Palestine, then approximately 19% of the total energy demand can be covered. Based on successful, established projects, Palestine has promising potential to generate low‐cost energy from bioresources. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd
Mechanisms driving the initiation and direction of endothelial sprouting in organotypic co‐culture of aorta and spinal cord tissues
Authors: Mikhailova Mariya M. , Volobueva Maria N. , Panteleyev Andrey A.
Published: April 2021

The resumption of blood supply in spinal cord (SC) after injury is a prerequisite of its recovery. To expose the mechanisms of damaged SC revascularization we have used an organotypic SC/aortic fragments (AF) co‐culture where, as we showed previously, damaged SC tissue induces AF cell sprouting but repels them away. Supplementation of culture medium with exogenous VEGF‐A165 redirects the migrating aortic endothelial cells towards SC tissue. This effect and the pattern of sFlt1 expression (a soluble form of VEGFR1) suggest that the low level of SC‐secreted VEGF and the presence of sFlt1 in SC slices together prevent the migration of aortic CD31+ cells to the SC in the absence of exogenous VEGF. VEGF‐A165 supplementation sequesters this inhibitory activity of sFlt1 by direct binding thus allowing CD31+ cell migration in to SC tissue. Proteome analysis has shown that migration/proliferation of CD31+ and αSMA+ aortic cells in neuronal culture medium used in our SC/AF model (which obstruct sprouting by itself) was resumed by combined action of several pro‐ (aFGF, bFGF, Osteopontin, TF, IGFBP2, SDF1) and anti‐angiogenic (Endostatin/Collagen18) factors. The mutual influence of AF and SC tissues is a key factor balancing these factors and thus driving endothelial sprouting in SC injury zone.
Rhodium‐Catalyzed Enantioselective Synthesis, Structures, and Properties of Single and Double Azahelicene‐Like Molecules
Authors: Hanada Kyoichi , Nogami Juntaro , Miyamoto Kazunori , Hayase Norihiko , Nagashima Yuki , Tanaka Yusuke , Muranaka Atsuya , Uchiyama Masanobu , Tanaka Ken
Published: April 2021

The enantioselective synthesis of aza[6] and [7]helicene‐like molecules have been achieved by the cationic rhodium(I)/axially chiral biaryl bisphosphine complex‐catalyzed intramolecular [2+2+2] cycloaddition of cyanodiynes. This protocol was successfully applied to the diastereo‐ and enantioselective synthesis of an S‐shaped double aza[6]helicene‐like molecule with a higheevalue of 89 %. Although no epimerization and racemization were observed in the double carbo[6]helicene‐like molecule at 80 °C, epimerization and racemization of the double aza[6]helicene‐like molecule proceeded at 80 °C. This double aza[6]helicene‐like molecule showed good fluorescent quantum yields and chiroptical responses under both neutral and acidic conditions.
Advanced Acceptor‐Substituted S,N‐Heteropentacenes for Application in Organic Solar Cells
Authors: Kraus Teresa , Lucas Sebastian , Wolff Pascal , Aubele Anna , Mena‐Osteritz Elena , Bäuerle Peter
Published: April 2021

Ambifunctional heterpentacenes with the heteroatom sequence SSNSS in the ladder‐type backbone were used either as donor or as nonfullerenic acceptor in solution‐processed bulk‐heterojunction solar cells. Different acceptor moieties and side chains were inserted. Synthesis and characterization of the systematically varied structural motifs provided insight in structure‐property relationships. Moreover, a dimeric heteroacene was synthesized, and the optoelectronic properties were compared to those of its monomeric counterpart.
The Versatile Electronic, Magnetic and Photo‐Electro Catalytic Activity of a New 2D MA2Z4 Family**
Authors: Chen Jiu , Tang Qing
Published: April 2021

The recent successful growth of MoSi2N4 and WSi2N4 monolayers led to the discovery of a new class of the two‐dimensional (2D) MA2Z4 materials with no known 3D layered allotropes, which renders great possibilities to integrate diverse properties by proper design of sandwiched “MZ2” building blocks and “A−Z” passivation layers. In this work, the dynamic stability, electronic properties, and surface reactivity of the new MA2Z4 family, in which M is Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, A refers to Si or Ge, and Z is N, P or As, is theoretically probed. Among the proposed 54 possible combinations, about 42 compositions are dynamically stable, which vary from non‐magnetic, anti‐ferromagnetic, to ferromagnetic semiconductors, metals and half‐metals. In particular, the VB (V, Nb, Ta) MA2Z4 possesses robust intrinsic ferromagnetism that is essential for spintronics applications. In regard to surface activity, most MA2Z4, particularly N‐ or P‐terminated IVB and VB MA2Z4, have high catalytic potential for hydrogen evolution, and the ▵GH of non‐magnetic MA2Z4 is highly correlated to the highest occupied p electronic states of the surface Z atoms. The photocatalytic activity is also evaluated. MoSi2N4 and WSi2N4 within 4 % tensile strain are capable of photocatalytic overall water splitting. The findings indicate the new 2D MA2Z4 family has fascinating properties and possesses strong potential for applications but not limited to electronics, spintronics and catalysts, which will stimulate the interests of experimental synthesis.
Modulation of Src Kinase Activity by Selective Substrate Recognition with Pseudopeptidic Cages
Authors: Tapia Lucía , Solozabal Naiara , Solà Jordi , Pérez Yolanda , Miller W. Todd , Alfonso Ignacio
Published: April 2021

The selective recognition of tyrosine residues in peptides is an appealing approach to inhibiting their tyrosine kinase (TK)‐mediated phosphorylation. Herein, we describe pseudopeptidic cages that efficiently protect substrates from the action of the Src TK enzyme, precluding the corresponding Tyr phosphorylation. Fluorescence emission titrations show that the most efficient cage inhibitors strongly bind the peptide substrates with a very good correlation between the binding constant and the inhibitory potency. Structural insights and additional control experiments further support the proposed mechanism of selective supramolecular protection of the substrates. Moreover, the approach also works in a completely different kinase‐substrate system. These results illustrate the potential of supramolecular complexes for the efficient and selective modulation of TK signaling.
Source and Risk Assessment of Trace Metals in Red Soils from Yunnan Province, Southwest China
Authors: Liang Bin , Han Guilin , Zeng Jie , Qu Rui , Liu Man , Liu Jinke
Published: April 2021

Trace metal pollution is one of the most concerning issues in Yunnan province, where red soil is the dominant soil. To investigate the sources of trace metals and assess their pollution level and potential risk, trace metal concentrations are measured in two red soil profiles from Yunnan province. Results show that Cr, As, and Zn are the most abundant trace metals in both profiles, and As and Cr might be pollutants because their concentrations are higher than the background values and the average concentrations in global soils from China, Japan, the UK, and the USA. The correlation matrix and principal component analysis exhibited that As and Cr are affected by mining activities. The single factor index and Nemero pollution index explained that the enrichment of As and Cr can lead to light pollution. The risk index (RI) values of trace metals exhibited a low ecological risk, of which the RI values of As and Cd in S1 are higher, implying a higher soil pollution level in south Yunnan. Furthermore, the HI results indicated that As can cause non‐carcinogenic risk on human health. This study is to help developing the management and preventing contamination of trace metals in red soils.
Web service quality of service prediction via regional reputation‐based matrix factorization
Authors: Ghafouri Seyyed Hamid , Hashemi Seyyed Mohsen , Razzazi Mohammad Reza , Movaghar Ali
Published: April 2021

Quality of Service (QoS) of Web services plays an essential role in selecting Web services by consumers. The dynamic QoS attributes of Web services have different values for different users. Therefore, the value of many Web services' QoS features for many users are undetermined, and these values should be predicted. The collaborative filtering (CF) method is one of the most successful approaches to predict these values. CF‐based methods use the QoS values contributed by the other users for prediction and, consequently, the values contributed by unreliable users can decrease the accuracy of prediction. To utilize the reputation of users can be regarded as one of the conventional approaches to overcome this problem. In this paper, we have defined a concept called regional reputation that represents the reputation of a user for users in each geographical region. Regional reputation has been achieved with the combination of the location information of the users and their reputation. Subsequently, by combining this concept with the matrix factorization, we have proposed a prediction method called regional reputation‐based matrix factorization. This approach has been able to improve the accuracy of prediction and be more persistent to the data contributed by unreliable users.
Analysis and design of ultra‐wideband low noise amplifier using complementary structure with series inductive peaking technique and shunt feedback
Authors: Kazemi Amir Hossein , Hayati Mohsen
Published: April 2021

In this paper, an ultra‐wideband low noise amplifier (LNA) is presented using 0.18‐μm RF CMOS technology. A complementary structure with series inductive peaking technique is introduced by using two inductor‐loops to achieve flat gain. In the first and third stages, two complementary structures are utilized to achieve a high and flat gain, a wideband input impedance matching and a low noise figure. In addition, a shunt feedback is utilized to increase input impedance matching and stability. In the second stage, a common source structure is used as interstage, which increases the −3 dB bandwidth. The designed LNA presents a high and flat gain of 15.6–16.5 dB, an excellent input return loss better than −11 dB and a good NF of 2.2–3 dB in the frequency range of 3.1–10.6 GHz. Also, the proposed structure consumes 6.8 mW from a 0.8‐V supply voltage and has an IIP3 of −4 dBm at 6.5 GHz. The proposed structure only occupies 0.59 mm2.
Prognostic significance of hematogone presence after autologous stem cell transplantation in patients with multiple myeloma
Authors: Göçer Mesut , Kurtoğlu Erdal
Published: April 2021

Background

Morphologically and immunophenotypically, the number of B‐lymphocyte progenitor cells, so‐called hematogones increases after chemotherapy and allogeneic stem cell transplantions. It is thought that hematogones can be used as a prognostic marker in these patients. It is aimed to determine the prognostic significance and factors affecting the development of hematogones, which can be seen after autologous stem cell transplantation in multiple myeloma (MM) patients.

Methods

This retrospective and single center study includes 80 patients who underwent autologous stem cell transplantation with the diagnosis of MM in our clinic between January 2013 and December 2019. The primary endpoint of the study was the relationship between the presence and rate of hematogone (HG) and progression free survival (PFS) and overall survival (OS). The secondary endpoint was to identify the factors affecting the development of HG.

Results

HG was detected in 61.2% of the patients. There was a moderate and positive linear correlation between the amount of stem cells given and HG ratio (r = 0.387, p = 0.000). PFS and OS were significantly shorter in the group with HG (p = 0.000 and p = 0.012).

Conclusions

HG positivity after autologous stem cell transplantation was found to be an independent prognostic marker for PFS and OS in patients with MM. There is a positive relationship between the amount of stem cells used during transplantation and the ratio of HG. As the amount of stem cells increases, the ratio of HG increases and when the ratio of HG increases, PFS and OS become shorter.
Promising Electrode and Electrolyte Materials for High‐Energy‐Density Thin‐Film Lithium Batteries
Authors: Lin Jie , Lin Liang , Qu Shasha , Deng Dongyuan , Wu Yunfan , Yan Xiaolin , Xie Qingshui , Wang Laisen , Peng Dongliang
Published: April 2021

All‐solid‐state thin‐film lithium batteries (TFLBs) are the ideal wireless power sources for on‐chip micro/nanodevices due to the significant advantages of safety, portability, and integration. As the bottleneck for increasing the energy density of TFLBs, the key components of cathode, electrolyte, and anode are still underway to be improved. In this review, a brief history of TFLBs is first outlined by presenting several TFLB configurations. Based on the state‐of‐the‐art materials developed for lithium‐ion batteries (LIBs), the challenges and related strategies for the application of those potential electrode and electrolyte materials in TFLBs are discussed. Given the advanced manufacture and characterization techniques, the recent advances of TFLBs are reviewed for pursuing the high‐energy‐density and long‐term‐durability demands, which could guide the development of future TFLBs and analogous all‐solid‐state lithium batteries.