bluuebunny/crossref_metadata_2025 huggingface dataset:
Variability, Association and Selection of Promising Characters for Breeding Creole Maize
Authors: Fontinele Yrle da Rocha , Santos Vanderley Borges dos , Nascimento Luan de Oliveira , Aragão Antônio Carnaúba de , Nascimento Matheus Matos do , Ferreira Almecina Balbino , Lima Antonia Fabiana Barros de , Moreira José Genivaldo do Vale , Araújo Dheme Rebouças de
Published: June 2021

Genetic variability is the main characteristic when seeking to select promising genotypes for plant breeding. Thus, the objective of this work was to investigate the genetic variability in agronomic and morphological characteristics of traditional varieties of maize, in addition to determining the degree of association and the selection of variety and promising characters to be explored in programs of genetic breeding of Creole maize. The experiment was conducted at the Federal University of Acre (UFAC), Rio Branco - Acre, in the 2017/2018 harvest period. A randomized block design was used, with five replications. The treatments were four varieties of Creole maize (V1, V2, V3 and V4) from the Vale do Juruá region and another hybrid cultivar LG 3040 (HI). The morpho-agronomic characteristics were evaluated in the useful area of the plots: days to silking (DS), days to anthesis (DA), plant height (PH) and height ear insertion (HEI), stem diameter (SD), mass of ear (ME), length ear (LE), diameter ear (DE), total grain mass (TGM), mass of 100 grain (M100G), grain moisture (GM) and grain productivity (GP). The data were subjected to analysis of variance and comparison of means. The values of genotypic and phenotypic variance were also estimated, heritability in the broad sense, selection accuracy, phenotypic, genotypic and environmental correlation, in addition to the principal component analysis (PCA). Variations in characteristics were found between the varieties of Creole maize and their interrelations, showing greater influence of ME, PH, TGM, M100G, DE and GP in the expression of the phenotype. Therefore, it is concluded that there is genetic variability in the characteristics evaluated, with emphasis to V4 that showed superior performance allowing direct selection of the characteristics SD, ME, TGM and M100G to be incorporated into an breeding program.
Substrate Design Augmentation for Die Placement Reference at Die Attach Process
Authors: Rodriguez Rennier , Graycochea Jr. Edwin , Gomez Frederick Ray
Published: June 2021

Die placement reference in die attach process is one of the critical aspects in measuring the actual die placement especially for the device that has a required measurement. This paper focused on the re-design on the layout of the substrate ball grid array (BGA) package with cross fiducials at the singulation lane which are located at the corner portions of the device. The cross fiducial would serve as a reference when measuring the actual placement of the Silicon die in the package. With this improvement, the technicians and operators could now easily identify the reference based on the mount and bonding diagram requirement.
Effect of Vibratory Therapy in Decreasing the Vaccination-induced Pain in Infants: Randomized Controlled Study
Authors: Taksande Amar , Chaudhary Shruti , Panwar Abhilasha Singh , Jhamb Aditi , Rao Rupesh , Jameel Patel Zeeshan , Damke Sachin , Meshram Revat
Published: June 2021

Background: Different non-medical therapies such as Non-nutritive sucking (NNS), oral sucrose with or without NNS (non-nutritive sucking), wrapping with thin blanket or cloth, kangaroo mother care (KMC), songs as well as multi-sensory stimulation are beneficial in pain reduction among neonates and infants.  According to the gate control theory, vibrations applied sat a site on the body block the nociceptive signals via the A???? and C fibers reducing the pain perception. When used along with many other nonpharmacological methods, This technique has been shown to minimize discomfort in pain-inducing treatments such as Intravenous cannulation, vaccines, heel prick, etc. The primary purpose of this study is to analyze vibrational therapy effects on infants  pain perception, thereby, providing evidence for a better pain management strategy in vaccination centers.

Objective: To determine the efficacy of vibration therapy on pain perception by infants during vaccine administration.

Material and Methods:  Out of total 90 eligible healthy infants who come for routinely immunization will be given either vibrational therapy (interventional group) or breastfeeding(control therapy) after doing randomization in this randomized controlled trial. The baseline vitals include cardiac rate (HR), respiratory rate (RR), and oxygen (SpO2) will be recorded before, during, and after vaccination during this treatment. Similarly, we will report Visual analog scales (VAS), Neonatal Infant Pain Scale (NIPS), and Wong-Baker FACES Pain Rating Scale, Modified Behavioral Pain Scale (MBPS)  after giving the vaccine to the infant.

Results: After completion of the study we will come to know the effect of vibratory therapy on pain control. The pain intensity with the help of the NIPS score will get less in the vibratory group than in the control group. The level of distress by using the Color Analogue Scale, MBPS scale, and FLACC scale, during the vaccine-related procedure will get a lower score in the infants  who has taken vibratory therapy than the control group.

Conclusion: study will probably give us information about vibration therapy, which will be an effective method for managing the pain after vaccination in infants.
A Comparative Study between Conventional Sutures, Staples and Adhesive Glue for Clean Elective Surgical Skin Closure
Authors: Mastud Kiran , Lamture Y. R. , Yeola(Pate) Meenakshi
Published: June 2021

Background: A surgeon's signature is 'scar' [1]. On a regular basis, surgeons face various kinds of wounds which must be healed. The healing process and cosmetic result can be influenced by wound and incision closure techniques.

The Goal of this Research is to Compare 3 Skin Closure Techniques: conventional skin sutures, adhesive glue, surgical stapler. These methods will be used to determine which of them is superior in terms of wound healing and cosmetic outcome in clean elective surgeries.

Objectives:

To compare duration between closure by 3 methods.

To compare prices amongst the 3 methods.

A comparison of the cosmetic appearances of the skin after closure.

A comparison of post-operative pain between the 3 methods.

To assess surgical site infections after closure with these 3 methods

Methodology: 90 patients, undergoing clean elective surgeries, will be included in this study. 30 patients will be included in every group. Hospitalised under Department of General Surgery in Datta Meghe Institute Of Medical Sciences, Wardha. The study will be conducted between October 2020 to October 2022.

Results: The result would be undertaken in SPSS software.

Conclusion: Conclusion will be based on findings of study protocol.
A Bibliometric Analysis of Pharmaceutical Sciences-Related Articles in Qatar from 2013-2020
Authors: Idoudi Sourour , Ibrahim Mohamed Izham Mohamed , Alali Feras , Billa Nashiru
Published: June 2021

Backgrround: Pharmaceutical science is an important area in drug discovery and therapies.The research output generated from pharmaceutical sciences research is critical for psychological, physical, and social wellbeing.

This study was carried out to analyze Qatar's quantity and quality of pharmaceutical sciences-related research and map out a national research roadmap and priority areas.

Materials and Methods: A systematic search was carried out in the Web of Science, Scopus, Pub Med, and Google Scholar databases using the search terms “Pharmaceutical Science,” “Pharmaceutical Chemistry,” “Medicinal Chemistry,” “Pharmacology,” “Pharmaceutics,” “Pharmacokinetics,” “Physiology,” “Pharmaceutical Science research,” “Study,” other relevant terms related to Pharmaceutical Sciences field and “Qatar.”The search covered eight years. The data extracted included the title, keywords, publication date, authors, publishing journal, journal ranking, impact factor, type of article, number of citations, the sum of citations, H-index, etc.

Results: The search yielded123 studies. Most were original articles (n=100, 81.3%), published in 2019 (n=27, 22.0%), applied research (n=68, 55.3%),indexed in Web of Science (n=120, 97.6%),published under the subject of pharmacology (n=43, 42.6%), focused on cancer (n=46, 37.4%)and produced by five authors (n=19, 18.8%) and more than eight authors (n=19, 18.8%). Hamad Medical Corporation (HMC) was the main collaborator (n=16, 13.0%). Fifty-four (43.9%) of the articles were published in journals ranked as Q1.

Conclusions: A total of 123 articles were published, with an average annual growth rate of 6.7% in publications and 946 citations. A high number of publications were in Q1 and Q2 journals. The research focus (e.g., cancer and cardiovascular) was established according to the country’s research roadmap and priority areas.
Role of Green Tea on Obesity and Type-II Diabetes Mellitus Male Individuals
Authors: Shah Tazeen , Dars Saira , Sheikh Saima Ashfaque , Shaikh Farheen , Ansari Shafaq , Akhtar Naheed , Ahmer Arslan
Published: June 2021

Objective: To evaluate the effects of Green tea on obesity and hyperglycemia.

Methodology: This observational study was carried out at the department of physiology, in affiliation to Medical Research Centre Liaquat University of Medical and Health Sciences Jamshoro. The sample was collected by convenient random sampling. Total 100 participants, 50 controls and 50 obese diabetics were enrolled. Informed written consent was taken from participants. The body mass index (BMI) of the participants was taken at the time of recruitment, and later at 16 weeks of consuming green tea. The serum glucose levels were assessed by fasting (FBS) and random blood sugar (RBS) levels, and HbA1C. The levels of serum Blood glucose were obtained with the glucose oxidase method. Data analysis was done on SPSS 21.0, analysis of variables was done by applying student t-test, the p-value of <0.05 was taken as statistically significant.

Results:100 participants recruited out of which 50 controls and 50 obese diabetics men, it was found that the prolong consumption of green tea for 16 weeks with 20-30 minutes’ walk had statistically significant declined in FBS, RBS, HbA1c, and BMI in the obese diabetic subjects, as compared to the controls.

Conclusion: This study concludes that the green tea has positive effect in reducing the total body weight and BMI and helps in maintaining the normoglycemic levels in Type 2 DM.
Phytopharmacological Assessment of Some Medicinal Plants of Thal Desert of Pakistan
Authors: Khalid Zunaira , Yasin Ghulam , Altaf Adeela , Batool Syeda Amna , Kanwal Asma , Sohail Sobia
Published: June 2021

The presence of secondary metabolites and various ions in a plant determines its phytophamacological potential. Desert plants are adapted to stressful environmet by synthesizing secondary metabolites and ions accumulation as osmoticum.The present study was conducted to evaluate the pharmacological potential of Thal desert plants in term of their metabolites and nutrient ions concentrations. Five specimens of seasonally available herbs and three of trees of Thal desert plants were colected. After collection specimens were analysed for alkaloids, terpenoids, tannins, sugar and ion contents. The data were analyzed statistically and means were compared by Duncan’s Multiple Range Test. Among the herbs Panicum antidotale root showed highest terpenoid, K+ ion and Ca+ ion contents. The herb Aerva javanica stem showed lowest alkaloid, tannin, soluble sugar, phosphorus, potassium and calcium contents. Among trees specimens, Tamarix aphylla leaves showed highest soluble sugar, phosphorous, potassium and calcium contents. Stem of Acacia modesta showed the lowest alkaloid, terpenoid, phosphorous and potassium contents.
Enhancement of Solubility and Dissolution Rate of BCS Class-II Fluvoxamine Tablets using Solvent Evaporation Solid Dispersion Technique
Authors: Srinivas Martha , Singh Anoop
Published: June 2021

Aim: This research work was aimed to formulate Enhancing the solubility of Poorly soluble drug i.e. Fluvoxamine tablets by the solvent evaporation method, Fluvoxamine medicament is a selective serotonin reuptake inhibitor (SSRI) antidepressant agent.

Purpose: The BCS class II drug Fluvoxamine consist low aqueous solubility and low oral bioavailability, for this reason to improve the biological performance of Fluvoxamine drug by solid dispersion mechanism.

Methodolgy: The drug Fluvoxamine was formulated by using solvent evaporation technique, solid dispersions of Fluvoxamine were prepared with different carriers in different ratios of PEG 6000 & Mannitol (1:1, 1:2 and 1:3).

Results: Results of prepared solid dispersions of Fluvoxamine by solid dispersion method Finally by comparing all the formulations, formulation (SF3) containing Fluvoxamine and PEG 6000 (1:3) shows better results.

Conclusion: Here we concluded that the poorly soluble drug solubility improving by solvent evaporation solid dispersion mechanism, and also developed six Fluvovamine formulations (FDF1-FDF6) during this FDF4 shows maximum (98.9±0.8%) drug release at the end of time.
Comparative Pharmaceutical Standardization and Oral Bioavailability Study on Praval Pishti and Praval Bhasma
Authors: Satpute Megha , Rathi Bharat , Wanjari Anita , Khan Mujahid
Published: June 2021

Background: Praval (coral) is a very usually occurring calcium form. It is rich source of calcium & minerals. As per text it can be converted into two formulas which are bhasma (calcinated ash) and pishti(powdered form without agni).These forms may have different rate of immersion. This needs to be studied.

Aim: Pharmaceutical Standardization study of Praval Pishti & Praval Bhasma and comparative evaluation of their relative oral bioavailability.

Materials and methods: The two formulations will be prepared from Praval (coral). By triturating with Gulab jala Praval Pishti will be prepared and by traditional Puta method Praval Bhasma will be prepared. The prepared formulations will be assessed for Bhasma Pariksha mentioned in Ayurveda. Organoleptic characters, Physicochemical parameters and Particle size distribution analysis, SEM –EDX (Scanning Electron Microscopy, Energy Dispersive X-Ray Analysis), FTIR (Fourier-transform infrared spectroscopy), XRD (X-Ray Diffraction), and GCMS (Gas Chromatography Mass Spectroscope) will be evaluated. To assess the relative oral bioavailability of Praval Pishti & Praval Bhasma study will be conducted in healthy volunteers and will be compared with the standard calcium supplement.

Observation and results: The study will be assessed for its relative oral bioavailability in healthy Volunteers by using unpaired “t” Test, One-way ANOVA.

Conclusion: The pharmaceutical study of Praval Bhasma and Praval Pishti will provide the standard parameters and comparative evaluation with standard will generate evidence for better bioavailability.
The Catalytic Enantioselective Stetter Reaction
Authors: Flanigan Darrin M. , Ozboya Kerem E. , Tanpure Subhash D. , Muñoz Alberto , Blakemore Paul R. , Rovis Tomislav
Published: June 2021

The catalytic enantioselective Stetter reaction is the coupling of an aldehyde with an electron‐deficient alkene via the conjugate addition of an acyl anion equivalent (Breslow intermediate) generated from the aldehyde and a chiral
N
‐heterocyclic carbene (NHC) catalyst. The process affords 1,4‐dicarbonyl compounds and related systems, such as β‐nitroketones, in an efficient and atom‐economical fashion and with generally good‐to‐excellent enantioselectivities when fused polycyclic chiral triazolylidenes are employed as the NHC catalysts. The scope of the transformation is particularly broad for intramolecular reactions, but in the case of the intermolecular variant, only certain types of aldehyde donors and electrophilic alkenes can be successfully coupled together.

This chapter describes theoretical and operational aspects of the catalytic enantioselective Stetter reaction such that the reader will be able to obtain optimal results in their own research. A detailed mechanistic overview is included to account for the factors that influence stereoselectivity and yield, and results from experimental and computational mechanistic studies are summarized. In addition, catalyst synthesis, reaction variants, applications in target‐directed synthesis, and comparison to other methods for generating 1,4‐dicarbonyl compounds are also presented. Tabular surveys are organized according to the modality of reactivity, either intra‐ or intermolecular, and the type of aldehyde donor. The literature is covered from the first disclosure of a catalytic enantioselective Stetter reaction in 1996 through to the end of 2019.
Hierarchically Porous Polymer and Carbon Monoliths via Controlled/Living Radical Polymerization
Authors: Kanamori Kazuyoshi , Hasegawa George , Nakanishi Kazuki
Published: June 2021

Cross‐linked monolithic polymer networks (or dried gels) with hierarchically porous structures have been prepared by controlled/living radical polymerization techniques such as nitroxide‐mediated radical polymerization (NMP), atom transfer radical polymerization (ATRP), and organotellurium‐mediated living radical polymerization (TERP). Well‐controllable macropores are formed as a transient structure of spinodal decomposition induced during the polymerization of monomers, and smaller pores in the macropore skeletons are resulted from secondary phase separation during the phase separation–gelation process. Also, the obtained networks are pyrolyzed in an inert atmosphere to obtain carbonaceous materials with abundant micropores while preserving the macro‐ and mesoporous morphology. In addition, applications of such hierarchically porous monolithic materials to separation media and electrochemical devices are demonstrated. In the present article, the concept, mechanism, methodology, and experimental results are discussed in detail.
Resveratrol reduces drug resistance of SCLC cells by suppressing the inflammatory microenvironment and the STAT3/VEGF pathway
Authors: Hou Cong , Lu Lijun , Liu Zhanye , Lian Yingjie , Xiao Jianguang
Published: June 2021

DNA‐damaging agents, such as doxorubicin (Adriamycin), are widely used for the treatment of small cell lung cancer (SCLC). However, drug resistance is one of the major challenges for treatment of SCLC. Herein, we investigated the mechanisms underlying drug resistance in SCLC cells and the effects of resveratrol (Res) on drug resistance. We report that Adriamycin treatment of H69AR (multidrug resistance phenotype) cells resulted in a lower rate of growth inhibition, up‐regulation of MRP1 and P‐glycoprotein (P‐gp), and higher P‐gp activity as compared with susceptible H69 cells treated with Adriamycin. Moreover, the signal transducer and activator of transcription 3/vascular endothelial growth factor (STAT3/VEGF) pathway was overactivated in H69AR cells, especially after interleukin‐23 treatment. The inflammatory microenvironment promoted the drug resistance of H69AR cells by activating the STAT3/VEGF pathway. The addition of Res suppressed the expression levels of inflammatory mediators, inhibited the STAT3/VEGF pathway, impeded P‐gp activity, and decreased the drug resistance of H69AR cells. H69AR cells exhibited Adriamycin resistance through activation of the STAT3/VEGF pathway, and Res ameliorated the inflammatory microenvironment to suppress the STAT3/VEGF pathway to reduce drug resistance. Our results suggest that Res may have therapeutic potential for SCLC treatment.
Atomic Force Microscopy, Transmission Electron Microscopy, Scanning Electron Microscopy, and FourierTransform‐InfraredSpectroscopic Imaging as Tools to Study Various Phenomena Involving Poly(Vinylpyrrolidone)
Authors: McMullen Roger L.
Published: June 2021

This chapter examine state‐of‐the‐art advanced imaging techniques and how these tools can be used to study polymer blends and composites containing poly(vinylpyrrolidone) (PVP) and its derivatives. The imaging technologies discussed consist of many of the modes of atomic force microscopy as well as basic and advanced methods in transmission electron microscopy (TEM) and scanning electron microscopy (SEM). There are two principal types of electron microscopy, SEM and TEM. Both techniques provide different types of information about the sample under investigation. The chapter demonstrates the use of Fourier transform–infrared (FT‐IR) spectroscopic imaging to spatially map elements of multicomponent systems. FT‐IR spectroscopic imaging is a technique that involves the coupling of an FT‐IR spectrometer with an optical microscope. Powerful tool based on AFM and IR spectroscopy has become available to researchers. The chapter also demonstrates the use of imaging technologies to characterize PVP‐metal nanoparticle composites with a specific focus on silver and gold particles.
Development, Application and Future Trends of Pyrrolidone‐ and Caprolactam‐Based Materials in the Pharmaceutical Industry
Authors: Hood David K. , Ananthraman Srinivasan , Musa Osama M.
Published: June 2021

The initial success of polyvinylpyrrolidone (PVP) as a blood plasma expander in Europe and later in the United States led to further clinical investigation into the polymer's biological interactions. Pharmaceutical excipients constitute the majority ingredients of a medicine. The excipients, apart from meeting the stringent quality and safety requirements for medical usage, play a crucial role in ensuring stability and bioavailability of the active principles. Solubility and solubilization are important concepts in the pharmaceutical industry. The chapter presents the discussions on delivery of drugs by nanoparticles and amorphous solid dispersions cover aspects of molecular complex formation between drugs and pyrrolidone‐ or lactam‐based materials. Formulations based on povidone iodine continue to remain popular even decades after their first uses for wound healing and antisepsis. Stronger binding in the lower dendrimers may have utility in certain drug delivery situations, where complex stability coupled to drug delivery to the destination are deemed critical to the treatment situation.
Safety and Toxicology of Pyrrolidones and Pyrrolidone‐Based Polymers
Authors: Kim Sang‐Tae , Schatz Anthony , Choi Christopher
Published: June 2021

This chapter aims to summarize and communicate the best available information to enable assessments of human health hazard, exposure, and risks that are associated with pyrrolidone chemistries in their intended applications. The pyrrolidone family of chemicals are high‐production derivatives of oxo‐pyrrolidines. The pyrrolidone family of chemicals include 2‐pyrrolidone, N‐methyl pyrrolidone (NMP), N‐vinyl pyrrolidone, lauryl pyrrolidone, N‐octyl pyrrolidone, and hydroxy ethyl pyrrolidone. The toxicity of pyrrolidone chemistries has been reviewed and assessed by numerous human health and environmental agencies worldwide. Pyrrolidone‐based polymers are versatile ingredients used in the cosmetics and beauty industry as a binder, film former, emulsion stabilizer, suspending/viscosity increasing agent, and hair fixative. A number of chronic studies have been conducted to determine the carcinogenic potential of polyvinylpyrrolidone. Consumer exposure to NMP can occur via the use of paint strippers. NMP is readily biodegradable and should be degraded within the wastewater treatment process.
Personal and Home Care Applications of Pyrrolidone‐ and Caprolactam‐Based Materials
Authors: Rigoletto Raymond , McMullen Roger L.
Published: June 2021

The key ingredients making up the framework of the formula must perform in the constraints of the intended chemical environment, such as in the high surfactant load of a shampoo or the extremes of pH found in household cleaners. In order to fully explain the features and benefits of polymer treatments on human hair to achieve cosmetic effects, such as care, styling, and treatment, it is essential to first consider the nature of hair and the important facets of its behaviour. Polymer adhesion to the surface of hair is a prerequisite for its use as a hair styling polymer. The chapter describes the technologies in the home care market space that include poly(vinylpyrrolidone) (PVP), poly(vinyl caprolactam), and their derivatives. PVP and its derivatives have been formulated into laundry care products, such as liquid detergents, to counteract dye transfer. Molecular modeling was also used to show the importance of conformational interactions of dyes with PVP.
Toward a standardized statistical methodology comparing optimum nitrogen rates among management practices: A bootstrapping approach
Authors: Francis Hannah R. , Ma Ting Fung , Ruark Matthew D.
Published: June 2021

There are a range of approaches to compare differences between or among optimum nitrogen (N) fertilizer rates resulting from different management practices; however, this goal lacks statistical standardization. To provide the statistical rigor needed to give clear recommendations for greater or less N need based on specific management practices, we propose a bootstrapping approach that resamples residuals with replacement. While bootstrapping is not new to data processing in agronomic fields, we provide an example of how to conduct residual‐resampled bootstrapping with nonlinear regression to identify differences in response curves, optimum N rates, and maximum yields using the FertBoot package in R. Our example dataset provides clear evidence of the value of the bootstrapping approach, as it can aid in determining significant differences between even relatively small differences in optimum N rate. We encourage adoption of this approach as a way to accurately evaluate differences in optimum fertilizer levels between or among treatments to better inform future agronomic decision making.
Coaching educators: Impact of a novel national faculty development program for didactic presentation skills
Authors: Jordan Jaime , Yarris Lalena M. , Dorfsman Michele L. , Wolf Stephen J. , Wagner Mary J.
Published: June 2021

Background

Didactic lectures remain common in medical education. Many faculty physicians do not receive formal training on public presentations or leading instructional sessions. Coaching has emerged in medical education with the potential to positively impact skills. We sought to evaluate a novel, national faculty peer‐coaching program created to improve lecture presentation skills and foster career development.

Methods

This was a mixed‐methods study of participant and faculty perceptions after completing the Council of Residency Directors in Emergency Medicine Academy Coaching Program. Participants completed an online evaluative survey consisting of multiple choice and Likert‐type items. Program coaches participated in semistructured interviews. Descriptive statistics were reported for survey data. Thematic qualitative analysis by two independent reviewers was performed on interview data.

Results

During 2012 to 2017, a total of 30 participants and 11 coaches from 37 residency programs across the United States engaged in the program. Twenty‐four (80%) participants completed the survey. Eight (73%) coaches participated in semistructured interviews. Data were collected between October and December 2018. The mean ± SD numbers of national presentations participants had given before and after the coaching program were 6.92 ± 7.68 and 16.42 ± 15.43, respectively. Since their coaching, most participants (87.5%) have been invited to give a lecture at another institution. Many participants felt that the program improved their lecture evaluations, public speaking, ability to engage an audience, and professional development. Almost all (92%) would recommend the program to a colleague. The coaches perceived multiple benefits including improved skills, self‐reflection, networking, career advancement, and personal fulfillment. Suggestions for improvement included improved administrative processes, more clear expectations, increased marketing, and increased participant and coach engagement.

Conclusion

Participants and coaches perceived multiple benefits from this novel, national faculty coaching program. With identification of the success, challenges, and suggestions for improvement, others may benefit as they develop coaching programs in medical education.
Stover harvest and tillage effects on corn seedling emergence
Authors: Agomoh Ikechukwu V. , Drury Craig F. , Reynolds W. Daniel , Woodley Alex , Yang Xueming , Phillips Lori A. , Rehmann Lars
Published: June 2021

Corn (Zea mays L.) stover is an increasingly important feedstock for biofuel and bioproduct production; however, excessive harvest of corn stover from agricultural fields may affect corn seedling emergence and subsequent plant population which may reduce corn growth and yield. Field experiments were conducted over four consecutive growing seasons in southwestern Ontario to determine under continuous corn cropping system the effects of no‐tillage (NT), conventional tillage (CT), and five rates of stover harvest (0, 25, 50, 75, and 100 wt. %) on corn seedling emergence in a Harrow sandy loam and in a Brookston clay loam. Time to achieve 50% seedling emergence (t0.5), emergence rate constant (kG), and final seedling population (MG) were adequately simulated using the Gompertz function. Irrespective of stover removal rate and soil type, t0.5 was 2 d longer, and kG was 32% lower, under NT compared to CT. In Harrow sandy loam, stover removal from NT reduced t0.5 in 1 out of 4 yr. The 100% removal reduced t0.5 relative to 0, 25, 50, and 75% removal by 1.1–2.2 d in 2015. Averaged across both tillages and all removal rates, kG was greater in Harrow sandy loam than in Brookston clay loam. Stover removal rates had no effect on MG but averaged over all removal rates and soil types, MG was 9% lower for NT compared to CT in 2016. No‐tillage practice under corn production can impede seedlings emergence early in the growing season and stover removal from the field can help mitigate against this effect.
Upper extremity musculoskeletal disorders and work exposures among railroad maintenance‐of‐way workers
Authors: Landsbergis Paul , Johanning Eckardt , Stillo Marco , Jain Rahul , Davis Michelle
Published: June 2021

Background

Our objective was to examine occupational risk factors for musculoskeletal disorders of the shoulders, elbows, wrists, and hands among railroad maintenance‐of‐way (MOW) workers. Little systematic research on musculoskeletal disorders has been conducted in this occupational group.

Methods

In total, 3995 active members of the Brotherhood of Maintenance of Way Employes Division (BMWED) completed a standardized survey focusing on disorders caused by hand‐transmitted vibration. We computed adjusted prevalence ratios (aPRs) using Poisson regression for shoulder, elbow, carpal tunnel syndrome, and vibration white finger musculoskeletal symptoms by work exposures, adjusted for age, region, race/ethnicity, smoking, potential second job, and spare time vehicle vibration exposure, and other work exposures.

Results

Among active male BMWED members, we found associations between >5.2 years (vs. 0.0–0.7 years) duration of full‐time equivalent power tool use and shoulder pain (aPR = 2.01; 95% confidence interval [CI], 1.43–2.85), elbow pain (aPR = 2.88; 95% CI, 1.86–4.46), vibration white finger symptoms (aPR = 2.49; 95% CI, 1.06–5.85), hand/wrist pain (aPR = 2.40; 95% CI, 1.74–3.32), finger numbness or tingling (aPR = 1.86; 95% CI, 1.38–2.50) and self‐reported carpal tunnel syndrome diagnosis (aPR = 2.16; 95% CI, 1.24–3.77). Associations were not consistent across outcomes for the duration of non‐powered hand tool use and “repeated lifting, pushing, pulling, or bending.” Positive gradients were observed for most outcomes.

Conclusions

Hand‐arm vibration and some other biomechanical exposures were associated with shoulder, elbow, wrist, hand, and finger symptoms. Prevention programs should address occupational risk factors for upper extremity musculoskeletal disorders among MOW workers.
Counterion Control oft‐BuO‐Mediated Single Electron Transfer to Nitrostilbenes to ConstructN‐Hydroxyindoles or Oxindoles
Authors: Zhao Yingwei , Zhu Haoran , Sung Siyoung , Wink Donald J. , Zadrozny Joseph M. , Driver Tom G.
Published: June 2021

tert‐Butoxide unlocks new reactivity patterns embedded in nitroarenes. Exposure of nitrostilbenes to sodium tert‐butoxide was found to produce N‐hydroxyindoles at room temperature without an additive. Changing the counterion to potassium changed the reaction outcome to yield solely oxindoles through an unprecedented dioxygen‐transfer reaction followed by a 1,2‐phenyl migration. Mechanistic experiments established that these reactions proceed via radical intermediates and suggest that counterion coordination controls whether an oxindole or N‐hydroxyindole product is formed.
High‐Performance Ladder‐Type Heteroheptacene‐Based Nonfullerene Acceptors Enabled by Asymmetric Cores with Enhanced Noncovalent Intramolecular Interactions
Authors: Tang Changquan , Ma Xiaoling , Wang Jin‐Yun , Zhang Xue , Liao Ruochuan , Ma Yunlong , Wang Peng , Wang Pengsong , Wang Tao , Zhang Fujun , Zheng Qingdong
Published: June 2021

Nonfullerene acceptors (MQ3, MQ5, MQ6) are synthesized using asymmetric and symmetric ladder‐type heteroheptacene cores with selenophene heterocycles. Although MQ3 and MQ5 are constructed with the same number of selenophene heterocycles, the heteroheptacene core of MQ5 is end‐capped with selenophene rings while that of MQ3 is flanked with thiophene rings. With the enhanced noncovalent interaction of O⋅⋅⋅Se compared to that of O⋅⋅⋅S, MQ5 shows a bathochromically shifted absorption band and greatly improved carrier transport, leading to a higher power conversion efficiency (PCE) of 15.64 % compared to MQ3, which shows a PCE of 13.51 %. Based on the asymmetric heteroheptacene core, MQ6 shows an improved carrier transport induced by the reduced π–π stacking distance, related with the increased dipole moment in comparison with the nonfullerene acceptors based on symmetric cores. MQ6 exhibits a PCE of 16.39 % with a VOC of 0.88 V, a FF of 75.66 %, and a JSC of 24.62 mA cm−2.
Selective 13C‐Labels on Repeating Glycan Oligomers to Reveal Protein Binding Epitopes through NMR: Polylactosamine Binding to Galectins
Authors: Moure María J. , Gimeno Ana , Delgado Sandra , Diercks Tammo , Boons Geert‐Jan , Jiménez‐Barbero Jesús , Ardá Ana
Published: June 2021

A combined chemo‐enzymatic synthesis/NMR‐based methodology is presented to identify, in unambiguous manner, the distinctive binding epitope within repeating sugar oligomers when binding to protein receptors. The concept is based on the incorporation of 13C‐labels at specific monosaccharide units, selected within a repeating glycan oligomeric structure. No new chemical tags are added, and thus the chemical entity remains the same, while the presence of the 13C‐labeled monosaccharide breaks the NMR chemical shift degeneracy that occurs in the non‐labeled compound and allows the unique identification of the different components of the oligomer. The approach is demonstrated by a proof‐of‐concept study dealing with the interaction of a polylactosamine hexasaccharide with five different galectins that display distinct preferences for these entities.
Manipulations of Chiroptical Properties in Belt‐Persistent Cycloarylenes via Desymmetrization with Heteroatom Doping
Authors: Fukunaga Toshiya M. , Sawabe Chizuru , Matsuno Taisuke , Takeya Jun , Okamoto Toshihiro , Isobe Hiroyuki
Published: June 2021

A desymmetrization strategy has been devised in the design of molecular cylinders to maximize the dissymmetry factor relevant to circularly polarized light. Although the highest dissymmetry factor of organic molecules was previously achieved with a chiral belt‐persistent cycloarylene having magnetic and electric transition dipole moments in parallel, we noticed that an unbalanced magnitude of two moments was detrimental for higher dissymmetry factors. In this study, a molecular cylinder was desymmetrized by arraying doped and undoped panels via stereoselective cross‐coupling macrocyclization. The desymmetrization succeeded in balancing two moments by reducing the electric transition moment at the global minimum but failed to maximize the dissymmetry factor. Structural studies revealed that the dissymmetry factor is sensitive to subtle structural fluctuations, while the rotatory strength is not affected. This study is important for the development of chiroptical materials.
Synergistic Catalysis by Brønsted Acid/Carbodicarbene Mimicking Frustrated Lewis Pair‐Like Reactivity
Authors: Chan Yi‐Chen , Bai Yuna , Chen Wen‐Ching , Chen Hsing‐Yin , Li Chen‐Yu , Wu Ying‐Yann , Tseng Mei‐Chun , Yap Glenn P. A. , Zhao Lili , Chen Hsuan‐Ying , Ong Tiow‐Gan
Published: June 2021

Carbodicarbene (CDC), unique carbenic entities bearing two lone pairs of electrons are well‐known for their strong Lewis basicity. We demonstrate herein, upon introducing a weak Brønsted acid benzyl alcohol (BnOH) as a co‐modulator, CDC is remolded into a Frustrated Lewis Pair (FLP)‐like reactivity. DFT calculation and experimental evidence show BnOH loosely interacting with the binding pocket of CDC via H‐bonding and π‐π stacking. Four distinct reactions in nature were deployed to demonstrate the viability of proof‐of‐concept as synergistic FLP/Modulator (CDC/BnOH), demonstrating enhanced catalytic reactivity in cyclotrimerization of isocyanate, polymerization process for L‐lactide (LA), methyl methacrylate (MMA) and dehydrosilylation of alcohols. Importantly, the catalytic reactivity of carbodicarbene is uniquely distinct from conventional NHC which relies on only single chemical feature of nucleophilicity. This finding also provides a new spin in diversifying FLP reactivity with co‐modulator or co‐catalyst.
Photo Click Reaction of Acylsilanes with Indoles
Authors: Stuckhardt Constantin , Wissing Maren , Studer Armido
Published: June 2021

Light‐mediated coupling of acylsilanes with indoles is reported. This photo click reaction occurs under mild conditions (415 nm) mostly in quantitative yield and provides stable silylated N,O‐acetals via light mediated siloxycarbene generation with subsequent indole‐N‐H insertion. We show that this very efficient and fully atom economic coupling process can be applied to conjugate complex systems, as documented by the clicking of carbohydrates with indole alkaloids. The method is also applicable to the conjugation of polymer chains. The linking acetal moiety can be readily cleaved and it is also shown that wavelength‐selective coupling and cleavage with acyl silanes bearing a second photoactive moiety is possible. This is documented by a successful polymerization/depolymerization sequence and by a polymer folding/unfolding process.
Photoinduced Reversible Semicrystalline‐to‐Amorphous State Transitions of Stereoregular Azopolyesters
Authors: Li Jie , Wang Meng‐Wie , Liu Ye , Ren Wei‐Min , Lu Xiao‐Bing
Published: June 2021

We report the synthesis of isotactic azobenzene‐based polyesters (azopolyesters) with main‐chain chirality via highly enantioselective resolution copolymerization of racemic azobenzene‐containing epoxides with cyclic anhydrides. All polyesters with trans‐azobenzene moieties were found to be semicrystalline materials with melting temperatures of 153–231 °C, while the corresponding isotactic cis‐azopolyesters were amorphous. The azobenzene groups in the copolymers exhibited reversible trans‐to‐cis and cis‐to‐trans photoisomerization upon irradiation with light. This demonstrates that the crystallinity of isotactic azopolyesters can be manipulated via photoinduced reversible isomerization. In addition, mixing isotactic trans‐polyesters with different enantiomeric configurations in a 1:1 mass ratio afforded crystalline stereocomplexes for which the crystalline behavior differed significantly from those of the component enantiomer. Also, photoinduced reversible transitions between semicrystalline and amorphous states were observed in various stereocomplexes of isotactic trans‐azopolyesters, similar to the isotactic azopolyesters themselves.
Capture and Separation of SO2 Traces in Metal–Organic Frameworks via Pre‐Synthetic Pore Environment Tailoring by Methyl Groups
Authors: Xing Shanghua , Liang Jun , Brandt Philipp , Schäfer Felix , Nuhnen Alexander , Heinen Tobias , Boldog Istvan , Möllmer Jens , Lange Marcus , Weingart Oliver , Janiak Christoph
Published: June 2021

Herein, we report a pre‐synthetic pore environment design strategy to achieve stable methyl‐functionalized metal–organic frameworks (MOFs) for preferential SO2 binding and thus enhanced low (partial) pressure SO2 adsorption and SO2/CO2 separation. The enhanced sorption performance is for the first time attributed to an optimal pore size by increasing methyl group densities at the benzenedicarboxylate linker in [Ni2(BDC‐X)2DABCO] (BDC‐X=mono‐, di‐, and tetramethyl‐1,4‐benzenedicarboxylate/terephthalate; DABCO=1,4‐diazabicyclo[2,2,2]octane). Monte Carlo simulations and first‐principles density functional theory (DFT) calculations demonstrate the key role of methyl groups within the pore surface on the preferential SO2 affinity over the parent MOF. The SO2 separation potential by methyl‐functionalized MOFs has been validated by gas sorption isotherms, ideal adsorbed solution theory calculations, simulated and experimental breakthrough curves, and DFT calculations.
Influence of Iron Sulfide Nanoparticle Sizes in Solid‐State Batteries**
Authors: Dewald Georg F. , Liaqat Zainab , Lange Martin Alexander , Tremel Wolfgang , Zeier Wolfgang G.
Published: June 2021

Given the inherent performance limitations of intercalation‐based lithium‐ion batteries, solid‐state conversion batteries are promising systems for future energy storage. A high specific capacity and natural abundancy make iron disulfide (FeS2) a promising cathode‐active material. In this work, FeS2 nanoparticles were prepared solvothermally. By adjusting the synthesis conditions, samples with average particle diameters between 10 nm and 35 nm were synthesized. The electrochemical performance was evaluated in solid‐state cells with a Li‐argyrodite solid electrolyte. While the reduction of FeS2 was found to be irreversible in the initial discharge, a stable cycling of the reduced species was observed subsequently. A positive effect of smaller particle dimensions on FeS2 utilization was identified, which can be attributed to a higher interfacial contact area and shortened diffusion pathways inside the FeS2 particles. These results highlight the general importance of morphological design to exploit the promising theoretical capacity of conversion electrodes in solid‐state batteries.
Dissecting the Flash Chemistry of Electrogenerated Reactive Intermediates by Microdroplet Fusion Mass Spectrometry
Authors: Hu Jun , Wang Ting , Zhang Wen‐Jun , Hao Han , Yu Qiao , Gao Hang , Zhang Nan , Chen Yun , Xia Xing‐Hua , Chen Hong‐Yuan , Xu Jing‐Juan
Published: June 2021

A novel mass spectrometric method for probing the flash chemistry of electrogenerated reactive intermediates was developed based on rapid collision mixing of electrosprayed microdroplets by using a theta‐glass capillary. The two individual microchannels of the theta‐glass capillary are asymmetrically or symmetrically fabricated with a carbon bipolar electrode to produce intermediates in situ. Microdroplets containing the newly formed intermediates collide with those of the invoked reactants at sub‐10 microsecond level, making it a powerful tool for exploring their ultrafast initial transformations. As a proof‐of‐concept, we present the identification of the key radical cation intermediate in the oxidative dimerization of 8‐methyl‐1,2,3,4‐tetrahydroquinoline and also the first disclosure of previously hidden nitrenium ion involved reaction pathway in the C−H/N−H cross‐coupling between N,N′‐dimethylaniline and phenothiazine.
Ultrafast Water Transport in Two‐Dimensional Channels Enabled by Spherical Polyelectrolyte Brushes with Controllable Flexibility
Authors: Dai Liheng , Xu Fang , Huang Kang , Xia Yongsheng , Wang Yixing , Qu Kai , Xin Li , Zhang Dezhu , Xiong Zhaodi , Wu Yulin , Guo Xuhong , Jin Wanqin , Xu Zhi
Published: June 2021

Fast water transport channels are crucial for water‐related membrane separation processes. However, overcoming the trade‐off between flux and selectivity is still a major challenge. To address this, we constructed spherical polyelectrolyte brush (SPB) structures with a highly hydrophilic polyelectrolyte brush layer, and introduced them into GO laminates, which increased both the flux and the separation factor. At 70 °C, the flux reached 5.23 kg m−2 h−1, and the separation factor of butanol/water increased to ≈8000, which places it among the most selective separation membranes reported to date. Interestingly, further studies demonstrated that the enhancement of water transport was not only dependent on the hydrophilicity of the polyelectrolyte chains, but also influenced by their flexibility in the solvent. Quartz crystal microbalance with dissipation and molecular dynamics simulations revealed the structure‐performance correlations between water molecule migration and the flexibility of the ordered polymer chains in the 2D confined space.
Synergistic toughening of epoxy resin byCTBNandCM‐β‐CD
Authors: Yin Xiangyun , Xie Zhipeng , Liu Qi , Yuan Xubo , Hou Xin , Zhao Jin
Published: June 2021

Carboxymethyl‐β‐cyclodextrin (CM‐β‐CD) and carboxyl terminated liquid nitrile rubber (CTBN) were used as binary component fillers in toughening the epoxy resin (E‐54). For a single component filler system, the addition of CTBN resulted in significantly improved fracture toughness but reduction of glass transition temperature (Tg) and modulus of epoxy resin. On the other hand, the addition of CM‐β‐CD resulted in a modest increase in modulus andTg, and significant improvement in toughness. This work provides a promising route of nanocomposites with excellent toughness. Besides the mechanism of synergistic toughening in this project was explained, and the major toughening mechanisms were attributed to interfacial micro‐cracks, energy dissipation of CM‐β‐ CD. This work gives us a further understanding of the modification effect of β‐ CD.
Silver–N‐heterocyclic carbene complexes‐catalyzed multicomponent reactions: Synthesis, spectroscopic characterization, density functional theory calculations, and antibacterial study
Authors: Mnasri Aziza , Mejri Amal , Al‐Hazmy Sadeq M. , Arfaoui Youssef , Özdemir Ismail , Gürbüz Nevin , Hamdi Naceur
Published: June 2021

Nowadays, silver–N‐heterocyclic carbene (silver–NHCs) complexes are widely used in medicinal chemistry due to their low toxic nature toward humans. Due to the success of silver–NHCs in medicinal applications, interest in these compounds is rapidly increasing. Therefore, the interaction of N,N‐disubstituted benzimidazolium salts with Ag2O in dichloromethane to prepare novel Ag(I)–NHCs complexes was carried out at room temperature for 120 h in the absence of light. The obtained complexes were identified and characterized by 1H and 13C nuclear magnetic resonance, Fourier‐transform infrared, UV–Vis, and elemental analysis techniques. Then, the silver complexes were applied for three‐component coupling reactions of aldehydes, amines, and alkynes. The effect of changing the alkyl substituent on the NHCs ligand on the catalytic performance was investigated. In addition, it has been found that the complexes are antimicrobially active and show higher activity than the free ligand. The silver–carbene complexes showed antimicrobial activity against specified microorganisms with MIC values between 0.24 and 62.5 μg/ml. These results showed that the silver–NHC complexes exhibit an effective antimicrobial activity against bacterial and fungal strains. A density functional theory calculation study was performed to identify the stability of the obtained complexes. All geometries were optimized employing an effective core potential basis, such as LANL2DZ for the Ag atom and 6‐311+G(d,p) for all the other atoms in the gas phase. Electrostatic potential surfaces and LUMO–HOMO energy were computed. Transition energies and excited‐state structures were obtained from the time‐dependent density functional theory calculations.