bluuebunny/crossref_metadata_2025 huggingface dataset:
Determination of Incidence of Soft Tissue Reactions after Total Hip Replacement using Elastography and Role of Elastography in Screening of Periprosthetic Soft Tissue: A Prospective Observational Study
Authors: Khera Ruchit , Sandhu Parvinder Singh , Sandhu Hardas Singh , Kapoor Atul
Published: August 2022

Introduction: Adverse local tissue reactions after Total Hip Replacement (THR) have been widely described in literature recently as a course of aseptic loosening. Evaluation for any adverse soft tissue reactions is challenging with traditional imaging techniques like Magnetic Resonance Imaging (MRI), and are limited, due to production of metallic artifact. Ultrasound, specifically its refined form elastography, has emerged recently as a useful tool for assessing the soft tissues. Aim: To determine the incidence of soft tissue reactions in cases of THR and to evaluate role of elastography in assessment of periprosthetic soft tissue. Materials and Methods: This prospective observational study was conducted in the Department of Orthopaedics, Dr. Hardas Singh Orthopaedic Hospital, Amritsar, Punjab, India, from May 2013 to April 2014. Study comprises of consecutively followedup 66 hips which were evaluated and assessed clinically and radiologically using ultrasound elastography for periprosthetic soft tissue and degree of fibrosis. The MRI was done in patients with positive findings only. Diagnosis was then confirmed with biopsy in patients who underwent revision surgery. Incidence of clinical symptoms, implant loosening, stability of implant, various types of soft tissue reactions, pseudotumour formation and synovial hypertrophy were determined and association between clinical and radiological findings was done. Chi-square test was determined to see the statistical significance. Results: Total of 66 hips were studied in 60 patients with mean age of 56.08±16.55 years (26-95 years). The incidence of soft tissue reactions observed in the study was 83.3% (n=55), of all 66 hips 36 were symptomatic, Implant loosening was seen in 29 hips, pseudotumours were detected in 3 (4.5%) hips, cystic nodules in 2 (3.0%) hips, enlarged lymph nodes in one (1.5%) hip, fibrogranuloma in 2 (3%) hips and synovial thickening was seen in 12 hips. Association of Harris Hip Score with capsular thickness, implant stability and acetabular loosening was found to be statistically significant. Conclusion: The study shows a substantially higher incidence of soft tissue reaction and capsular hypertrophy following THR. Ultrasound elastography is a good screening tool to detect early soft tissue changes in periprosthetic tissue.
Profitability of Watermelon Production Diversification Strategy: Evidence from Smallholder Farmers in Taraba State, Nigeria
Authors: Dauda I. , Anthony D. B. , Ruben J. , Kara H. A.
Published: August 2022

The profitability of a watermelon production diversification plan for smallholder farmers in Taraba State, Nigeria, was investigated in this study. During the 2021 farming season, data for the study was collected from 355 randomly selected farms. Descriptive statistics and a farm budgeting approach were utilized to assess the data. The mean age of respondents was 42.3 years, 85.1% of them were married with an average household of six people. The majority (77.5%) of the respondents were educated with a mean farming experience of 8.6 years. On average, the respondents cultivate 4.2 hectares of land. The budgeting technique showed that a mixture of melon and cowpea has the highest average net farm income, followed by a mixture of melon and Bambara-nut while a mixture of melon and groundnut has the least average net farm income per hectare. The estimated gross margin and net farm income for all the enterprises stood at N 143618.11 and N 135051.13 respectively. The return on the owner's labour and management for all the enterprises is N 87801.13 and the return on investment is 127.58%. This demonstrates that the watermelon crop diversification strategies in the research area are profitable. A melon and cowpea combination was discovered to be more profitable than other firms. Because of this, it is suggested that a large amount of land be set aside for growing this crop.
Effect of Landscape on Consumers’ Behavior in Shopping Malls: An Empirical Study of Shoprite Malls at Akure, Nigeria
Authors: Kayode Oloruntoba , Oluwabukola Asaolu Catherine , Abiodun Oloye Rowland
Published: August 2022

Consumer behaviors have become prominent in the business platform and related discipline from past to present. Being able to understand consumer behaviors and identify strategies in this direction has become the most important condition for survival in competitive conditions. This study, it is aimed to determine the relationship between consumption concepts and architectural discipline. Design criteria that increase and decrease consumption preference and quantity have been investigated by determining the extent to which the interior and exterior architecture via landscape affected the consumption habits. Relevant literature, observations, and conceptual survey of the daily shopping malls were conducted at Shoprite Mall Akure. The Data was analyzed using Structural Equation Model (SEM) via AMOS to measure the architectural impacts on consumer shopping patterns. Thus, the findings show that a desirable landscape improves consumers' patronage tendency in shopping malls. This implies that architectural training and practice are sacrosanct in human shopping tendency.
Impact of Extra-curricular Activities on Students’ Academic Performance at Secondary Schools in Samdrup Jongkhar
Authors: Penjor Ugyen , Dorji Thinley
Published: August 2022

The purpose of the study was to find out the impact of extracurricular activities on the academic performance of student at secondary schools in Samdrup Jongkhar District. The sample consisted of 471 students from classes (IX-XII) from seven secondary schools in Samdrup Jongkhar. The classes were selected randomly. The study used a mixed method mode approach. The quantitative component comprises of 24 items of 4 Likert scale survey questionnaires categorized under three themes. The qualitative component incorporated students’ perception on the impact of extracurricular activities in academic performance was collected through open-ended questions. The data were analyzed using descriptive analysis (means and standard deviation) and inferential t-test was use for analysis of hypothesis. The qualitative raw data was thematically analyzed (transcribed, coded and categorized). The study concluded that that student who participated in extra-curricular activities have positive influence on students’ life with high academic performance, more regular attendance and better self image. It is recommended that the school should give opportunity to students to participate in extracurricular activities irrespective of the level that they study.
Predicting the Major Organism Species in Tobacco in Cao Bang Province, Vietnam Based on the Weather Conditions
Authors: Chin Nguyen Van , Van Nguyen Van , Tuan Tao Ngoc , Thanh Pham Ha
Published: August 2022

In recent years, some organism species are appearing popularly in the tobacco in Cao Bang province, Vietnam, and caused severe damage to the tobacco yield and quality such as budworm (Helicoverpa assulta Guene), aphid (Myzus persicea Sulzer), and powdery mildew (Erysiphe cichoracearum D.C). To manage them effectively, forecasting and controlling insect pests play an important role in tobacco cultivation. The predictive model was built base on the Skybit, Fuzzy, and Degree-days model to forecast and give suitable control methods for major insect pests in tobacco. This model is run on Excel software and calculated by an IF function for the growth of the organism. Result of the model predicted accurately the tobacco budworm, aphids, and powdery mildew damaging tobacco in Cao Bang in April 2022. Based on the results of prediction, we give proper control methods for each insect pests, preventing the quick growth and development of the organism species in the field, reducing the use of pesticides, and increasing the income of the growers. This model has also applied to forecast other pests in the tobacco in Vietnam. To increase the quality of the prediction, the model will continue to be perfected and completed in the coming years based on the practice field.
América Latina: regímenes de bienestar en transición durante los años noventa
Authors: Barba Solano Carlos
Published: August 2022

Este artigo analisa o andamento do processo de ajuste e de reforma social impulsionado pelas instituições financeiras internacionais e por numerosos governos na América Latina, especialmente nos anos 90. Apresenta as características do paradigma de bem-estar que chegou a ser hegemônico em escala regional e discute as conseqüências de aplicarem-se as mesmas receitas a realidades nacionais muito diversas. Para analisar a heterogeneidade regional, recorre ao conceito de “regime de bem-estar” e emprega uma tipologia que permite mostrar os efeitos diferenciais dos processos aqui abordados. O artigo aponta a necessidade do uso de um paradigma de bem-estar distinto para enfrentar os profundos desafios sociais postos aos países da região, ou seja, assinala a urgência de uma reforma da reforma. PALAVRAS-CHAVE: regimes de bem-estar, pobreza, políticas sociais, transição social, América Latina. LATIN AMERICA: welfare system in transition during the nineties Carlos Barba Solano This paper analyzes the course of the adjustment and social reform processes impelled by international financial institutions and numerous governments in Latin America, especially in the nineties. It presents the characteristics of the welfare paradigm that achieved hegemony in a regional scale and discusses the consequences of applying the same recipes to very diverse national realities. To analyze the regional heterogeneity, it falls back upon the concept of “welfare system” and uses a typology that shows the differential effects of the processes approached here. The paper points the need of the use of a different welfare paradigm to face the deep social challenges put to the countries of the area, in other words, it marks the urgency of a reform of the reform. KEYWORDS: welfare system, poverty, social policies, social transition, Latin America. AMÉRIQUE LATINE: les régimes de bienêtre en phase de transition au cours des années quatre-vingt-dix Carlos Barba Solano Cet article analyse la progression du processus d’ajustement et de réforme sociale provoquée par les institutions financières internationales et par de nombreux gouvernements en Amérique Latine, tout spécialement au cours des années 90. Les caractéristiques du paradigme de bien-être dont le caractère hégémonique a atteint une échelle régionale y sont présentées et les conséquences dues au fait d’appliquer les mêmes formules à des réalités nationales très diverses y sont discutées. Afin d’analyser l’hétérogénéité régionale, on a recours au concept de “régime de bien-être” et on utilise une typologie qui permet de montrer les effets différentiels des processus qui ont été abordés. Dans cet article le besoin d’utiliser un paradigme de bien-être différent pour affronter les profonds défis sociaux auxquels sont confrontés les pays de la région est mis en évidence, c’est-à-dire qu’on y montre l’urgence d’une réforme de la réforme. MOTS-CLÉS: régimes de bien-être, pauvreté, politiques sociales, transition sociale, Amérique Latine. Publicação Online do Caderno CRH: http://www.cadernocrh.ufba.br
A QUESTÃO DA REPRESENTAÇÃO POLÍTICA NA PRIMEIRA REPÚBLICA
Authors: Buarque de Hollanda Cristina
Published: August 2022

O artigo trata o tema da representação política na Primeira República brasileira (1889-1930) a partir de três importantes matrizes de reflexão sobre a questão: o liberalismo, o positivismo e o realismo. Busca-se rejeitar a narrativa usual das primeiras décadas republicanas, baseada unicamente no diagnóstico de corrupção política, e iluminar outras faces importantes do cenário político da época. A despeito das diferenças significativas entre os modelos interpretativos em evidência, que constituem o cerne do artigo, eles convergem na expectativa de protagonismo do Estado na tarefa de unificação e criação do povo. THE QUESTION OF POLITICAL REPRESENTATION IN THE FIRST BRAZILIAN REPUBLIC Cristina Buarque de Hollanda The paper treats the theme of political representation in the First Brazilian Republic (1889-1930) starting from three important reflection matrixes on the subject: the liberalism, the positivism and the realism. One aims to reject the usual narrative of the first republican decades, based only on the diagnosis of political corruption, and to illuminate other important faces of the political scenery at the time.  In spite of significant differences among the interpretative models in evidence, that constitute the core of this paper, they converge in the expectation of protagonism of the State in the creation of the people and unification task. KEYWORDS: First Republic, political representation, liberalism, positivism, realism. LA REPRÉSENTATION POLITIQUE PENDANT LA PREMIÈRE RÉPUBLIQUE BRÉSILIENNE Cristina Buarque de Hollanda Cet article aborde le thème de la représentation politique, au cours de la Première République brésilienne (1889-1930), à partir de trois perspectives importantes de réflexion : le libéralisme, le positivisme et le réalisme. On essaie de ne pas prendre en considération la narrative habituelle des premières décennies républicaines, basée uniquement sur le diagnostic de la corruption politique, et de montrer d’autres aspects importants du scénario politique de l’époque. En dépit des différences significatives entre les modèles interprétatifs mis en évidence, qui constituent le noyau de cet article, il existe une convergence qui va dans le sens d’une attente, celle de voir l’État devenir le protagoniste de l’unification et de la formation du peuple. MOTS-CLÉS: Première République, représentation politique, libéralisme, positivisme, réalisme. Publicação Online do Caderno CRH: http://www.cadernocrh.ufba.br
TÉCNICAS DE NEUTRALIZACIÓN: una teoría de la delincuencia
Authors: M’Cready Sykes Gresham , Matza David
Published: August 2022

Este artigo apresenta evidências que sugerem que os delinqüentes geralmente não aprovam a delinqüência. Eles se envolvem na delinqüência por meio do emprego de certas “técnicas de neutralização”. Embora eles acreditem que a delinqüência seja má, eles pretendem que seus atos são justificáveis por diferentes tipos de razões. Estas justificativas são utilizadas antes do ato delinqüente, fazendo com que este seja possível pela neutralização da crença dos indivíduos que eles são ruins. PALAVRAS CHAVE: delinqüência, aprendizagem, justificativas morais, crenças, técnicas de neutralização. TECHNIQUES OF NEUTRALIZATION: a delinquency theory Gresham M. Sykes David Matza This article presents evidences that suggest that criminals do not usually approve of delinquency. They end in the delinquency through certain “neutralization techniques”. Although they believe delinquency is bad, they say that their actions are justifiable for different types of reasons. These justifications are used before the deliquent action, making it possible by the neutralization of the individuals’ beliefs that they are bad. WORDS KEY: delinquency, learning, moral justifications, beliefs, neutralization techniques. TECHNIQUES DE NEUTRALISATION: une théorie de la délinquance Gresham M. Sykes David Matza Cet article met en évidence des éléments qui indiquent qu’en général les délinquants ne sont pas pour la délinquance. Ils entrent dans la délinquance en utilisant certaines “techniques de neutralisation”. Même s’ils croient que la délinquance est mauvaise, ils prétendent que leurs actes sont justifiables pour diverses raisons. Ces justifications sont utilisées avant les actes de déliquance, permettant ainsi que celles-ci soient utilisées pour neutraliser l’idée des gens qu’ils sont mauvais. MOTS-CLÉS: délinquance, apprentissage, justifications morales, croyances, techniques de neutralisation. Publicação Online do Caderno CRH: http://www.cadernocrh.ufba.br
Five-Year Allograft Survival for Recipients of Kidney Transplants From Hepatitis C Virus Infected vs Uninfected Deceased Donors in the Direct-Acting Antiviral Therapy Era
Authors: Schaubel Douglas E. , Tran Amelia H. , Abt Peter L. , Potluri Vishnu S. , Goldberg David S. , Reese Peter P.
Published: August 2022

This cohort study examines the validity of the Kidney Donor Profile Index’s hepatitis C virus (HCV) penalty during the direct-acting antiviral era by comparing 5-year allograft survival between recipients of kidneys from HCV-RNA–positive donors vs HCV-RNA–negative donors.
Discordance Between Oncology Clinician–Perceived and Radiologist-Intended Meaning of the Postradiotherapy Positron Emission Tomography/Computed Tomography Freeform Report for Head and Neck Cancer
Authors: Patel Zachary , Schroeder Jennifer A. , Bunch Paul M. , Evans Joni K. , Steber Cole R. , Johnson Adam G. , Farris Joshua C. , Hughes Ryan T.
Published: August 2022

Importance

Assessment of response after radiotherapy (RT) using 18F–fluorodeoxyglucose positron emission tomography (PET) with computed tomography (CT) is routine in managing head and neck squamous cell carcinoma (HNSCC). Freeform reporting may contribute to a clinician’s misunderstanding of the nuclear medicine (NM) physician’s image interpretation, with important clinical implications.

Objective

To assess clinician-perceived freeform report meaning and discordance with NM interpretation using the modified Deauville score (MDS).

Design, Setting, and Participants

In this retrospective cohort study that was conducted at an academic referral center and National Cancer Institute–designated Comprehensive Cancer Center and included patients with HNSCC treated with RT between January 2014 and December 2019 with a posttreatment PET/CT and 1 year or longer of follow-up, 4 masked clinicians independently reviewed freeform PET/CT reports and assigned perceived MDS responses. Interrater reliability was determined. Clinician consensus–perceived MDS was then compared with the criterion standard NM MDS response derived from image review. Data analysis was conducted between December 2021 and February 2022.

Exposures

Patients were treated with RT in either the definitive or adjuvant setting, with or without concurrent chemotherapy. They then underwent posttreatment PET/CT response assessment.

Main Outcomes and Measures

Clinician-perceived (based on the freeform PET/CT report) and NM-defined response categories were assigned according to MDS. Clinical outcomes included locoregional control, progression-free survival, and overall survival.

Results

A total of 171 patients were included (45 women [26.3%]; median [IQR] age, 61 [54-65] years), with 149 (87%) with stage III to IV disease. Of these patients, 52 (30%) received postoperative RT and 153 (89%) received concurrent chemotherapy. Interrater reliability was moderate (κ = 0.68) among oncology clinicians and minimal (κ = 0.36) between clinician consensus and NM. Exact agreement between clinician consensus and the NM was 64%. The NM-rated MDS was significantly associated with locoregional control, progression-free survival, and overall survival.

Conclusions and Relevance

The results of this cohort study suggest that considerable variation in perceived meaning exists among oncology clinicians reading freeform HNSCC post-RT PET/CT reports, with only minimal agreement between MDS derived from clinician perception and NM image interpretation. The NM use of a standardized reporting system, such as MDS, may improve clinician-NM communication and increase the value of HNSCC post-RT PET/CT reports.
Effect of employers' concerns about cancer countermeasures on the implementation of cancer screening and support for balancing cancer treatment and work in small and medium-sized Japanese enterprises
Authors: Minamitani Masanari , Tatemichi Masayuki , Mukai Tomoya , Katano Atsuto , Nakagawa Keiichi
Published: August 2022

Objective

Japan has recently implemented screening and support to balance cancer treatment and work. The present study evaluated whether the interest of employers in small and medium-sized enterprises (SMEs) affects cancer control in the workplace.

Methods

Cancer preparedness at work was examined by a Japanese life insurance company contracting 370 000 SMEs. The analysis targeted SMEs hiring ≤50 employees whose employer was aged ≥40 years. The endpoints were performing one or more screening for stomach, colon, or lung cancer recommended for both sexes in Japan and implementing three or more supportive measures from the nine systems listed in a questionnaire. Logistic regression analysis was performed to predict these endpoints using other factors.

Results

The survey was completed from January 5 to 28, 2022 and included 5268 eligible companies. Around half were small enterprises with up to five employees. Screenings were performed for stomach (32%), colorectal (27%), and lung (26%) cancers. Sick leave (36%) was the most common support for balancing cancer treatment and work. Logistic regression analysis revealed that employer's concern was a significant predictor of screening (odds ratio [OR] = 3.59, P < .001) and support (OR = 2.55, P < .01) compared with “not concerned at all,” along with industry type, annual sales, experience of employees with cancer, and employer's participation in screening.

Conclusion

Our findings suggested that employers' interest was a powerful predictor of implementing cancer control in SMEs. Educational intervention targeted toward the employer could play a critical role in improving SMEs.
A cohesin‐associated gene score may predict immune checkpoint blockade in hepatocellular carcinoma
Authors: Liu Cui‐Zhen , Li Jian‐Di , Chen Gang , He Rong‐Quan , Lin Rui , Huang Zhi‐Guang , Li Jian‐Jun , Du Xiu‐Fang , Lv Xiao‐Ping
Published: August 2022

Stromal antigen 1 (STAG1), a component of cohesion, is overexpressed in various cancers, but it is unclear whether it has a role in the transcriptional regulation of hepatocellular carcinoma (HCC). To test this hypothesis, here, we screened global HCC datasets and performed multiscale embedded gene co‐expression network analysis to identify the potential functional modules of differentially expressed STAG1 co‐expressed genes. The putative transcriptional targets of STAG1 were identified using chromatin immunoprecipitation followed by high‐throughput DNA sequencing. The cohesin‐associated gene score (CAGS) was quantified using the The Cancer Genome Atlas HCC cohort and single‐sample gene set enrichment analysis. Distinct cohesin‐associated gene patterns were identified by calculating the euclidean distance of each patient. We assessed the potential ability of the CAGS in predicting immune checkpoint blockade (ICB) treatment response using IMvigor210 and GSE78220 cohorts. STAG1 was upregulated in 3313 HCC tissue samples compared with 2692 normal liver tissue samples (standard mean difference = 0.54). A total of three cohesin‐associated gene patterns were identified, where cluster 2 had a high TP53 mutated rate and a poor survival outcome. Low CAGS predicted a significant survival advantage but presaged poor immunotherapy response. Differentially expressed STAG1 co‐expression genes were enriched in the mitotic cell cycle, lymphocyte activation, and blood vessel development. PDS5A and PDGFRA were predicted as the downstream transcriptional targets of STAG1. In summary, STAG1 is significantly upregulated in global HCC tissue samples and may participate in blood vessel development and the mitotic cell cycle. A cohesin‐associated gene scoring system may have potential to predict the ICB response.
Effective Hydrogenation Strategies to Boost Efficiency over 20% for Crystalline Silicon Solar Cell with Al2O3/Cu2O Passivating Contact
Authors: Li Le , Ying Lei , Lin Yinyue , Li Xiaodong , Zhou Xi , Du Guanlin , Gao Yi , Liu Wenzhu , Lu Linfeng , Wang Jilei , Yang Liyou , Zhang Shan‐Ting , Li Dongdong
Published: August 2022

Passivation interlayers such as Al2O3 are required to improve the hole selectivity of dopant‐free passivating contact based on transition metal oxides. For the interlayer to provide low surface recombination as in conventional silicon heterojunctions (SHJs) or tunnel oxide passivated contact (TOPCon) technologies, “hydrogenation” strategies to effectively introduce hydrogen in passivation interlayers while being compatible with transition metal oxides (TMOs) are urgently sought after. In this work, an easy‐to‐implement strategy to successfully incorporate extra hydrogen in the Al2O3 passivation layer is developed. The chemical and field‐effect passivation mechanisms of the extra hydrogen are revealed via comprehensive experimental analyses and density functional theory calculations. By implementing H‐Al2O3 with Cu2O as the hole‐selective rear contact in p‐type crystalline silicon (c‐Si) solar cells, a remarkable efficiency of 20.35% is achieved (fill factor of 84.76%). The study highlights a promising approach to improve the passivation quality of dielectric interlayers and boost the performance of dopant‐free c‐Si solar cells to compete against mainstream c‐Si photovoltaics technologies.
Infrared‐to‐THz Detection and Spectroscopy with Whispering‐Gallery‐Mode Microresonators
Authors: D'Ambrosio Davide , Capezzuto Marialuisa , Aiello Roberto , Delli Santi Maria Giulia , Sorgi Alessia , Malara Pietro , Avino Saverio , Giorgini Antonio , Maddaloni Pasquale , Consolino Luigi , Vitiello Miriam Serena , Natale Paolo De , Gagliardi Gianluca
Published: August 2022

A novel room‐temperature photodetector based on a silica‐microsphere optical resonator operating from the mid‐infrared to the terahertz spectral region is reported. The sensor relies on a free‐space visible laser whose frequency is locked to the center of a whispering‐gallery mode (WGM). The devised scheme automatically tracks any small change in the microresonator's size and refractive index that occurs upon illumination with radiation absorbed by silica. In this way, direct detection of quantum‐cascade laser beams around 4.3 and 111 μm wavelengths is shown, down to minimum noise‐equivalent power levels of ≈1 pW √Hz−1 with a dynamic range >100 dB. The microsphere resonator is then exploited, for the first time, as a photodetector in absorption spectroscopy of the 12CO2 fundamental ro‐vibrational band and of very‐weak 13CH3OH rotational lines.
Rhodium‐Catalyzed Asymmetric Hydrohydrazonemethylation of Styrenes: Access to Chiral Hydrazones, Hydrazides, Hydrazines and Amines
Authors: Kliemann Max N. , Teeuwen Simon , Weike Christopher , Franciò Giancarlo , Leitner Walter
Published: August 2022

The catalytic asymmetric hydroformylation of styrenes was combined with condensation of the resulting aldehydes with acetohydrazide as nucleophile leading to γ‐chiral N’‐substituted aceto‐hydrazones. This cascade reaction is called hydrohydrazonemethylation (HHM) in analogy to similar hydroformylation/condensation sequences. The catalyst was formed in situ from the commercially available chiral phosphine‐ligand (R,R)‐Ph‐BPE and [Rh(acac)(CO)2] and used at a loading of 0.2 mol%. The stable condensation products are not prone to tautomerization providing versatile chiral intermediates. Their one‐pot reduction with DMAB/TsOH resulted in the corresponding γ‐chiral N’‐substituted acetohydrazides (14 examples) with yields ranging from 73% to 91% and enantioselectivities from 77% to 97% ee. Deprotection of the acetohydrazides led to the corresponding β‐chiral hydrazines. Reduction and hydrogenolysis of the hydrazones over Raney‐Ni yielded the corresponding β‐chiral primary amines with 95% ee. Diastereoselective functionalization of the C=N bond of the hydrazones is a further synthetic option, as demonstrated by allylation with (allyl)SiCl3.

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γ‐Pyronecarbaldehyde‐Based Practical Asymmetric Catalytic Synthesis of Chiral 2,4‐Dihydroxycarboxylic Acids andα‐Hydroxy‐γ‐lactones
Authors: Smirnov Maxim V. , Kucherenko Alexander S. , Gridnev Ilya D. , Korlyukov Alexander A. , Zlotin Sergei G.
Published: August 2022

Biomass derivedγ‐pyrone‐2‐carbaldehydes were proposed as robust heterocyclic platform for carrying out organocatalytic asymmetric cross‐aldol reactions with various aldehydes and ketones in high yield with excellent diastereoselectivity and enantioselectivity. Origins of efficient stereoinduction were revealed by quantum‐chemical calculations of four possible transition states. The products were converted to synthetically useful chiral 2,4‐dihydroxy carboxylic acid derivativesviaprotection/deprotection and RuIII‐catalyzed oxidative fragmentation steps without racemization of stereogenic centers. The developed approach was applied for asymmetric synthesis of chiral pantolactones, valuable precursors of biologically active substances and natural products, and for synthesis of Dexpanthenol, a medication used for treating defects in the barrier function of skin.

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Potentiation of Drug Toxicity through Virus Latency Reversal Promotes Preferential Elimination of HIV Infected Cells
Authors: Truong Thanh Tung , Hayn Manuel , Frich Camilla Kaas , Olari Lia‐Raluca , Ladefoged Lucy Kate , Olesen Morten T. Jarlstad , Jakobsen Josefine H. , Lunabjerg‐Vestergaard Cherie K. , Schiøtt Birgit , Münch Jan , Zelikin Alexander N.
Published: August 2022

Eliminating latently infected cells is a highly challenging, indispensable step toward the cure for HIV/AIDS. Hypothesis put forward herein is that the unique HIV protease cut site (Phe‐Pro) can be reconstructed using a potent inhibitor of tubulin polymerization, monomethyl auristatin F (MMAF), which features Phe at its C‐terminus. This presents opportunities to design prodrugs that are specifically activated by the HIV protease. To this end, a series of MMAF derivatives is synthesized and evaluated in cell culture using latently HIV‐infected cells. The cytotoxicity of compounds is indeed enhanced upon latency reversal by up to 11‐fold. As a result, in a mixed cell population, nanomolar concentrations of the lead compounds depletes predominantly the HIV‐infected cells and in doing so markedly enriches the pool of the uninfected cells. Affinity of the lead compounds to the viral protease is validated computationally and experimentally but despite expectations, the mechanism of action of the synthesized toxins is shown to be independent from the enzymatic activity of the HIV protease.
One Hundred‐Nanometer‐Sized CsPbBr3/m‐SiO2 Composites Prepared via Molten‐Salts Synthesis are Optimal Green Phosphors for LCD Display Devices
Authors: Liu Zheming , Sinatra Lutfan , Lutfullin Marat , Ivanov Yurii P. , Divitini Giorgio , De Trizio Luca , Manna Liberato
Published: August 2022

The exploitation of the optimal optical properties of lead halide perovskite nanocrystals in optoelectronic devices is mainly hindered by the low stability of such materials. Here, a molten‐salts approach is developed to encapsulate CsPbBr3 nanocrystals (together with KNO3, NaNO3, and KBr inorganic salts) inside different nanoscale mesoporous SiO2 host matrices, having sizes between 100 and 300 nm. The comparison between optical properties and stability of the products, including the previously reported ≥600‐nm‐sized CsPbBr3/m‐SiO2 composite, indicates that 100‐nm‐sized CsPbBr3/m‐SiO2 particles feature the best stability against humidity, light irradiation and heat, and exhibit a green (peaked at 517 nm) narrow photoluminescence (full width at half maximum of 18 nm) with high quantum yield (77%). Such properties make these composite particles optimal green phosphors for down conversion liquid crystal displays (LCDs). Indeed, the authors demonstrate that a proof‐of‐concept 7‐in. LCD in which the green color conversion layer is a polymer film loaded with 100‐nm‐sized CsPbBr3/m‐SiO2 particles, features an optimal white emission (with correlated color temperature of 6861 K), that is close to the reference white point of NTSC, and covers 92% of NTSC standard color gamut area of CIE1931, higher than that of a reference commercial LCD (Dell XPS 15 7590 laptop).
Design and experimental analysis of a novel slant‐plate photoreactor
Authors: Zhao Jianyong , Ren Guangmin , Li Zizhen , Meng Xiangchao
Published: August 2022

A novel slant‐plate photoreactor (SPR) immobilized with titanium dioxide (P25) was developed to address the disadvantage that the effluent on the backlight side of the corrugated plate photoreactor could not be treated. The SPR was tested and analyzed regarding the degradation of phenol under UV light. For comparison, a flat‐plate photoreactor, a slurry photoreactor, and a corrugated plate photoreactor were also examined. The performance of SPR in phenol degradation was higher than either corrugated plate photoreactor with the same angle or flat‐plate. Furthermore, SPR exhibited highest energy utilization efficiency compared to the corrugated plate photoreactor with the same angle and flat‐plate photoreactor in phenol oxidation. The superior performance of SPR was due primarily to the highly exposed catalyst surface area, high mass transfer coefficient, and multiple reuses of reflected light. In addition, the SPR was tested under natural solar light for its possible implementation in practice.
Development of energy‐optimum aromatic extraction processes using ionic liquid [EMIM][NTf2]
Authors: McNeeley Adam , Tsai Chang‐Che , Lin Shiang‐Tai , Liu Y. A.
Published: August 2022

There is industrial incentive to extract aromatics from ethylene cracker feeds, but the conventional sulfolane solvent was found not economical by Meindersma and coworkers. Ionic liquids (ILs) have long been considered alternative aromatic extraction solvents. This work develops energy‐optimum aromatic extraction processes for an ethylene cracker feed using IL solvents. We avoid pitfalls of using simplified feeds and a priori thermodynamic property estimates, with the largest set of experimentally regressed UNIQUAC binary parameters for the IL, 1‐ethyl‐3‐methylimidazolium bis([trifluoromethyl]sulfonyl)imide ([EMIM][NTf2]). We screen process energy and operating conditions for [EMIM][NTf2] and sulfolane at varying aromatic feed contents and find [EMIM][NTf2] favorable at low aromatic feed contents. Adding light and heavy components of the ethylene cracker feed necessitates process modifications. Our novel steam‐assisted extractive distillation developed for [EMIM][NTf2] is also suitable for sulfolane. We show that the [EMIM][NTf2] solvent can reduce 10.7% of energy consumption compared to sulfolane using the same novel process.
Electrocatalytic Hydrogenation and Reductive Coupling of Aryl Ketones: Highly efficient Straightforward Metal‐Free Access to Alcohols and Pinacols
Authors: Chowdhury Sushobhan , Kumar Ajay , Kumar Ajay
Published: August 2022

An electrocatalytic pathway is disclosed for the hydrogenation and reductive pinacol coupling of aryl ketones. The operationally simple protocol neither requires an external catalyst nor any sacrificial anode and proceeds efficiently under the aerobic condition at an ambient temperature and pressure. Under the optimized condition, diaryl ketones transform completely to the corresponding diarylmethanols whereas aryl ketones undergo reductive pinacol coupling leading to the respective 1,2‐diol compounds in good to excellent yields. The protocol showed a high degree of substrate compatibility with moderate to very good diastereoselectivity depending on the substrates. The scope of the developed method was also extended to the different bioactive molecules opening up the possibility for their late‐stage synthetic modification.
Programming and Dynamic Control of the Circular Polarization of Luminescence from an Achiral Fluorescent Dye in a Liquid Crystal Host by Molecular Motors
Authors: Hou Jiaxin , Toyoda Ryojun , Meskers Stefan C. J. , Feringa Ben L.
Published: August 2022

Circular polarized light is utilized in communication and display technologies and a major challenge is to develop systems that can be switched between left and right circular polarized luminescence with high degrees of polarization and enable multiple addressable stable states. Luminescent dyes in Liquid Crystal (LC) cholesteric phases are attractive systems to generate, amplify and modulate circularly polarized luminescence (CPL). In the present study, we employ light‐driven molecular motors as photo‐controlled chiral dopants in LCs to switch the handedness of the LC and the circular polarization of luminescence from an achiral dye embedded in the mesogenic material. Tuning of the color of the CPL and the retention time of the photoprogrammed helicity is demonstrated making use of a variety of motors and dyes. The flexibility offered by the design based on inherently chiral unidirectional rotary motors provides full control over CPL non‐invasively by light, opening possibilities for pixilated displays with externally addressable polarization.
Influence of the Building Unit on Covalent Organic Frameworks in Mediating Photo‐induced Energy‐Transfer Reversible Complexation‐Mediated Radical Polymerization (PET‐RCMP)
Authors: Lu Zhen , Zhao Rui , Yang Hongjie , Fu Xiaoling , Zhao Yulai , Xiao Longqiang , Hou Linxi
Published: August 2022

Two imine‐based covalent organic framework photocatalysts with different building units, TPB‐DMTA‐COF and TAT‐DMTA‐COF, for photo‐induced energy transfer reversible complexation‐mediated radical polymerization (PET‐RCMP) were developed and investigated, producing ideal polymers with accurate molecular weight and moderate dispersity under visible light irradiation. The chain extension and spatiotemporal control experiments revealed the high chain‐end fidelity of polymers and the compatibility of RCMP processes in both bulk and aqueous system. Moreover, density functional theory (DFT) calculations verified that heteroatom‐doped TAT‐DMTA‐COF exhibits higher activities for weakening C−I bond energy barrier, which promotes PET‐RCMP polymerization performance. This work demonstrates that rational adjustment of building block for constructing COF heterogeneous photocatalyst can enhance the catalytic performance of PET‐RCMP, providing a design methodology for the development of polymeric organic photoelectric semiconductor catalysts to mediate RCMP.
Insight into the Overlooked Photochemical Decomposition of Atmospheric Surface Nitrates Triggered by Visible Light
Authors: Wang Hong , Sun Yanjuan , Dong Fan
Published: August 2022

The nitrogen oxides (NOx) formed by photochemical reaction of surface nitrates raise significant concerns. However, little is known about the effect of visible light (>380 nm) on nitrate decomposition and the reaction mechanism. Herein, the decomposition of surface nitrates is investigated under visible light. The results indicate that visible light photocatalysis contributes significantly to nitrate decomposition. Monodentate nitrate (m‐NO3−) can be decomposed into NOx by photogenerated electrons starting from the weakly coordinated N−O bond. Water vapor promotes NOx generation because more stable bidentate nitrate (b‐NO3−) will be converted into m‐NO3− by surface hydroxyl groups through hydrogen bonding interactions. Alternatively, b‐NO3− can be directly decomposed to NO2− by NO attack, but this process is subject to photocatalytic oxidation. This work brings a new focus on the atmospheric NOx sources and provides a more nuanced understanding of nitrates decomposition processes.
Multidentate Chelation Heals Structural Imperfections for Minimized Recombination Loss in Lead‐Free Perovskite Solar Cells
Authors: Liu Gengling , Zhong Yang , Feng Wenhuai , Yang Meifang , Yang Guo , Zhong Jun‐Xing , Tian Tian , Luo Jian‐Bin , Tao Junlei , Yang Shaopeng , Wang Xu‐Dong , Tan Licheng , Chen Yiwang , Wu Wu‐Qiang
Published: August 2022

Tin‐based perovskite solar cells (Sn‐PSCs) have emerged as promising environmentally viable photovoltaic technologies, but still suffer from severe non‐radiative recombination loss due to the presence of abundant deep‐level defects in the perovskite film and under‐optimized carrier dynamics throughout the device. Herein, we healed the structural imperfections of Sn perovskites in an “inside‐out” manner by incorporating a new class of biocompatible chelating agent with multidentate claws, namely, 2‐Guanidinoacetic acid (GAA), which passivated a variety of deep‐level Sn‐related and I‐related defects, cooperatively reinforced the passivation efficacy, released the lattice strain, improved the structural toughness, and promoted the carrier transport of Sn perovskites. Encouragingly, an efficiency of 13.7 % with a small voltage deficit of ≈0.47 V has been achieved for the GAA‐modified Sn‐PSCs. GAA modification also extended the lifespan of Sn‐PSCs over 1200 hours.
Rapid Access to Diverse Multicomponent Hierarchical Nanostructures from Mixed‐Graft Block Copolymers
Authors: Liang Ruiqi , Song Qingliang , Li Ruipeng , Le An N. , Fu Xiaowei , Xue Yazhen , Ji Xiaoyu , Li Weihua , Zhong Mingjiang
Published: August 2022

Multicomponent nanostructured materials assembled from molecular building blocks received wide attention due to their precisely integrated multifunctionalities. However, discovery of these materials with desirable composition and morphology was limited by their low synthetic scalability and narrow structural tuning window with given building blocks. Here, we report a scalable and diversity‐oriented synthetic approach to hierarchically structured nanomaterials based on a few readily accessible building blocks. Mixed‐graft block copolymers containing sequence‐defined side chains were prepared through ring‐opening metathesis copolymerization of three or four types of macromonomers. Intramolecularly defined interfaces promoted the formation of ordered hierarchical structures with lattice sizes tunable across multiple length scales. The same set of macromonomers were arranged and combined in different ways, providing access to diverse morphologies in the resultant structures.
Evolution of a Strategy for Concise Enantioselective Total Synthesis of the Salinosporamide Family of Natural Products
Authors: Park Soojun , Lee Jiwoo , Kim Jae Hyun , Jeong Yeji , Lee Seokwoo , Lee Su Won , Kim Sanghee
Published: August 2022

Our first strategy for rapidly accessing pyrrolidinone cores of salinosporamides involved combined use of memory of chirality and dynamic kinetic resolution principles in aldol reactions of the serine‐derived 5‐oxazolidinone substrate, which was ultimately unsuccessful with respect to enantioselectivity. This failure led us to the revised strategy. The influence of the stereocenter in 5‐oxazolidinone enabled selective installation of the C‐2 stereocenter. The intramolecular aldol reaction of the C‐2 stereodefined aldol substrate was successful. An unexpected hydrolytic dynamic kinetic resolution was observed in hydrolyses of the bicyclic aldol products. This unprecedented substrate‐driven hydrolytic dynamic kinetic resolution was utilized in preparing the pyrrolidinone core with excellent efficiency. Through this strategy, the concise total syntheses of salinosporamides A and B as well as cinnabaramides A, E, and F were achieved with high selectivity.
Ein pas de deux eines NO‐Paares: synchrones lichtinduziertes Schalten von einem doppelt‐linearen zu einem doppelt‐gewinkelten Ru(NO)2‐Fragment bei gleich bleibender Nitrosylladung
Authors: Hasil Asma , Beck Daniel , Schröder Daniel , Pillet Sébastien , Wenger Emmanuel , Woike Theo , Klüfers Peter , Schaniel Dominik
Published: August 2022

Der {Ru(NO)2}10‐Dinitrosylrutheniumkomplex [Ru(NO)2(PPh3)2] (1) zeigt eine besondere Form lichtinduzierter Bindungsisomerie (PLI von photoinduced linkage isomerism): die beiden NO‐Liganden schalten bei Photoanregung synchron aus dem Grundzustand (GS) mit zwei annähernd linearen RuNO‐Funktionen in einen metastabilen Zustand (MS), der unter 230 K beständig ist und zu ≈50 % populiert werden kann. Der MS wurde experimentell durch Photokristallographie, IR‐Spektroskopie und DS‐Kalorimetrie als eine doppelt‐gewinkelte Variante des doppelt‐linearen GS charakterisiert. Die experimentellen Ergebnisse werden durch Rechnungen bestätigt – und um den Befund erweitert, dass der Übergang eine disrotatorische, synchrone 50°‐Drehung der beiden Nitrosylliganden ist. Obwohl 1 die übliche Rotverschiebung der N−O‐Valenzschwingung bei der Abwinkelung einer MNO‐Einheit zeigt, gibt es keine erhöhte Ladungsübertragung von Ru zu NO auf dem GS‐zu‐MS‐Pfad. Die Behandlung durch die Methode der effektiven Oxidationsstufe (EOS) zeigt beide Isomere von 1 und auch den Übergangszustand als Ru−II(NO+)2‐Spezies.
Die Einführung des Perfluorierten Cp*‐Liganden in die Koordinationschemie
Authors: Sievers Robin , Sellin Malte , Rupf Susanne M. , Parche Joshua , Malischewski Moritz
Published: August 2022

Die Reaktion zwischen AgBF4 und [Rh(COD)Cl]2 (COD=1,5‐Cyclooctadien) in Gegenwart von [NEt4][C5(CF3)5] ergab den perfluorcarbonlöslichen Komplex [Rh(COD)(C5(CF3)5)] durch Salzmetathese. Dieser Komplex stellt das erste Beispiel für eine erfolgreiche Koordination des schwach basischen [C5(CF3)5]−‐Liganden, seit dessen Erstsynthese im Jahr 1980 dar. Zusätzlich zu [Rh(COD)(C5(CF3)5)] wurde das Nebenprodukt [Rh(COD)(C5(CF3)4H)] isoliert und vollständig charakterisiert. Begleitende DFT‐Rechnungen zeigen, dass die Interaktionsenergie des [C5(CF3)5]−‐Liganden gegenüber dem 12‐Elektronen [Rh(COD)]+‐Fragment aufgrund verringerter elektrostatischer Interaktionen und einer schwächeren π‐Donorfähigkeit um ≈70 kcal mol−1 im Vergleich zu [C5(CH3)5]− erniedrigt ist. Die quantitative, jedoch reversible Substitution des [C5(CF3)5]−‐Liganden durch Toluol, die ihn in ein schwach koordinierendes Anion überführt, demonstriert experimentell die außergewöhnlich schwache Bindungssituation.
Hydrogen Bonding Directed Reversal of 13C NMR Chemical Shielding
Authors: Jena Subhrakant , Routray Chinmay , Dutta Juhi , Biswal Himansu S.
Published: August 2022

The deshielding or downfield 13C NMR chemical shift of amide carbonyl carbon upon H‐bonding is a widely observed phenomenon. This downfield shift is commonly used as a spectroscopic ruler for H‐bonding. However, the very first observation of an upfield 13C NMR of thiocarbonyl carbon in thioamides upon H‐bonding encouraged us to explore the physical origin of the reversal of 13C NMR chemical shielding. Careful NMR analysis shows that sulfur and selenium‐centered H‐bonds (S/SeCHBs) induce a shielding effect on the 13CC=S(Se) while changing from amides to thioamides or selenoamides. In addition, natural chemical shielding (NCS) analysis shows that the σ11 and σ22 components of the isotropic shielding tensor (σ) have a crucial role in this unusual shielding.
Scaling Catalytic Contributions of Small Self‐Cleaving Ribozymes
Authors: Egger Michaela , Bereiter Raphael , Mair Stefan , Micura Ronald
Published: August 2022

Nucleolytic ribozymes utilize general acid‐base catalysis to perform phosphodiester cleavage. In most ribozyme classes, a conserved active site guanosine is positioned to act as general base, thereby activating the 2′‐OH group to attack the scissile phosphate (γ‐catalysis). Here, we present an atomic mutagenesis study for the pistol ribozyme class. Strikingly, “general base knockout” by replacement of the guanine N1 atom by carbon results in only 2.7‐fold decreased rate. Therefore, the common view that γ‐catalysis critically depends on the N1 moiety becomes challenged. For pistol ribozymes we found that γ‐catalysis is subordinate in overall catalysis, made up by two other catalytic factors (α and δ). Our approach allows scaling of the different catalytic contributions (α, β, γ, δ) with unprecedented precision and paves the way for a thorough mechanistic understanding of nucleolytic ribozymes with active site guanines.