bluuebunny/crossref_metadata_2025 huggingface dataset:
Key Drivers of Digital Transformation in Greek Businesses: Strategy vs. Technology
Authors:   Hellenic Open University Patras, Karekla Maria , Pollalis Yannis ,   University of Piraeus, Angelopoulos Michail ,   University of Piraeus
Published: June 2021

Purpose: This article aims to assess strategy and technology as key drivers of Greek businesses’cdigital transformation and compare the results to those of international studies and sources. Methodology: A research was conducted on 124 Greek businesses from different sectors and industries with the use of an anonymous questionnaire from December 2019 to January 2020. Greek businesses were categorized as early, developing, and maturing according to their perceptions about the level of their digital maturity, and differences were identified. The results were finally compared to an international relevant survey. Findings: Several differences were located among the Greek businesses of the three digital maturity categories as formulated after their self-evaluation, and evolution has been identified on their perceptions about their digital strategy, its existence, objectives, and structure, which can be seen developing and expanding from the lowest to the highest levels of digital maturity. Originality: The findings can be useful in creating an initial picture of the perceptions and practices applied by Greek businesses to their use of digital technologies. They can also become a measure of comparison for the self-evaluation of Greek businesses in their efforts to digitally transform.
How Firms Cooperate in Business Groups? Evidence from Poland
Authors:   Warsaw School of Economics, Mierzejewska Wioletta , Dziurski Patryk ,   Warsaw School of Economics
Published: June 2021

Purpose: The study aims to identify the main directions of intragroup cooperation, along with crucial areas of cooperation in business groups, and develops theoretical models of cooperation in a business group. Methodology: The qualitative approach is applied in the study that is based on the cross-case analysis of four business groups operating in Poland. Findings: Results indicate that business groups cooperate mainly vertically (cooperation between the core company and affiliates) in operations. Horizontal (among affiliates) and vertical cooperation in other areas – marketing, R&D, finance, and human resources – are not so intense. The study enables us to propose a theoretical framework of cooperation models in business groups based on two dimensions – the direction of cooperation and the number of cooperation areas. It leads to the identification of four models: two-sided loose cooperation, two-sided tight cooperation, multi-sided loose cooperation, and multi-sided tight cooperation. Implications: Identification of main directions of cooperation in business groups, along with areas of cooperation have implications for both researchers and managers. Findings of the study and the theoretical framework of cooperation models in business groups can be used as a basis for the further theoretical exploration of the organization and functioning of business groups in the economy and a strategic decision guideline for managers. Originality: The literature focuses mainly on the interorganizational cooperation between dispersedly owned standalone entities. Studies on intraorganizational cooperation in business groups are limited. The study aims to provide a better understanding of cooperation between entities in business groups.
Leaving in Mascot of Silence: Organizational Determinants of Employee Turnover Intentions in Mediating and Moderating Roles of Quiescent Silence and Coworker Support in a Russian Context
Authors:   GIFT University Gujranwala, Kashif Muhammad , Petrovskaya Irina ,   Lomonsov Moscow State University Business School, Samad Sarminah ,   College of Business and Administration, Wijenayake Shanika ,   University of Kelaniya
Published: June 2021

Purpose: Drawing on social exchange theory (SET), this study explores the mediating role of quiescent silence as a link between organizational stressors and turnover intentions among Russian frontline employees (FLEs). Furthermore, we aim to investigate whether coworker support moderates the relationship between quiescent silence and turnover intentions. Research Methods: The study is a cross-sectional survey administered among a sample of 235 FLEs employed in Russian healthcare organizations. We analyzed the data with SmartPLS version 3.0. Findings: The results reveal that ethical conflict and abusive supervision are significantly related to quiescent silence. Quiescent silence mediates the relationship between abusive supervision, ethical conflict, and employee turnover intentions. Managerial Implications: There is a need to provide employees with opportunities to voice their opinions. However, what is crucial is the assurance of employee privacy while motivating them to voice opinions. Managers should be more proactive in diagnosing silence. Originality: This is the first study to explore the mediating role of quiescent silence on the relationship between organizational stressors and employee turnover intentions in a unique Russian healthcare context. The moderating role of coworker support to buffer the relationship between quiescent silence and turnover intentions is unique to this study.
Phenology of North American maple trees in the conditions of the Mari El Republic
Authors: Mukhametova Svetlana Valer'evna , Konakova Anastasiya Vital'evna , Sokolova Kristina Igorevna , Suchkova Anastasiya Alekseevna
Published: June 2021

The article contains the results of the 2014 - 2018 phenology observation over 6 maple tree species (Acer L.) with natural habitats in North America. The objects of research were plants of the Botanical garden-Institute of VSUT: A. negundo, A. pensylvanicum, A. rubrum, A. saccharinum, A. saccharum, A. spicatum. The studied maples began growing at the end of April – the first decade of May and ended in October. The first, in the first decade of May, bloomed A. saccharinum and A. rubrum. Later blooming species were characterized by a longer flowering period, the latest and longest flowering within 20 days was observed in A. spicatum. Despite the different periods of flowering, the fruits of different species ripened relatively amicably, in the second half of September. The longest vegetation period was found in A. saccharinum (169±2.1 days), and this species is characterized by late autumn leaf blooming. The greatest period of autumn leaf blooming, more than a month, was characterized by A. spicatum. The studied species can be used in landscaping of the Mari El Republic settlements as part of an additional assortment, with the exception of A. negundo, which is a weed plant. Despite the similar timing of the passage of many phenophases, the variety of maples morphological features (shape and size of leaves, flowers and fruits, bark color, etc.) allows them to be used for decorative purposes. During the study period, the earliest passage of most phenophases was recorded in 2016, and the latest in 2017 and 2018.
Boris Tishchenko and the new generation of Soviet composers of the 1960s: political and economic context
Authors: Serov Iurii Eduardovich
Published: June 2021

The subject of this research is the period of the Russian symphonic music of the early 1960s. The scene saw the emergence of a new generation of composers – the so-called “Sixtiers”, making themselves known with remarkable artistic achievements, novel and modern musical language. Emphasis is place on such aspects of the topic, as the system of music education that established in the Soviet Union by the mid XX century, sustained material affluence of the Soviet composers, and ideological pressure of the government in return for such care. Special attention. Special attention is given to the new artistic opportunities for the young Russian composers that emerged as a result of the political “thaw”. The scientific consists in introduction into the scientific discourse of a wide range of memoir literature and critical articles of the representatives of the “new wave” movement, as therefore, a more comprehensive understanding of the complex processes that unfolded in the Soviet academic music. A detailed analysis is conducted on the role and place in the struggle for “new music” of the youngest musician out of the “Sixtiers” – a prominent Russian symphonist of the XX century Boris Ivanovich Tishchenko (1939 – 2010). The main conclusion is reflected in the thought on a certain triumph of the School of Soviet Composers and the system of music education, which is most clearly described by the last three decades of the existence of the Soviet Union.
The peculiarities of dialectic of good and evil in works of the philosophers of the Early Modern Age (T. Hobbes, B. Spinoza, G. V. Leibniz)
Authors: Kovalev Andrei Andreevich
Published: June 2021

The subject of this research is the categories of good and evil in philosophy of the representatives of the Early Modern Age (on the example of the works of T. Hobbes, B. Spinoza, and G. W. Leibniz). These philosophers conceptualized the dialectic of good and evil leaning on the shifted paradigm at the turn of the Middle Ages and the Modern Age. However, the article advances a hypothesis that despite a fundamental turn in the philosophy of the Modern Age, the prevalent n medieval philosophy dialectic of good and evil had a strong impact upon the views of the philosophers of the Early Modern Age. The research employs the dialectical method and metaphysics, which allowed viewing the categories of good and evil from the perspective of the logical-philosophical position of their contradiction, as well as revealing their initial nature and the role in human world. The novelty of this study consists in the fact that in a certain sense it explores the dual dialectic: on the one hand, it is a longtime problems of good and evil, while on the other hand, the philosophy of good and evil of the Early Modern Age is ambiguous and contradictory, when the previous paradigm is no longer relevant, although a new philosophical concept of good and evil is yet to be formed. There is a good reason why the author chos the ideas of T. Hobbes, B. Spinoza, and G. W. Leibniz – their approaches towards the problem of good and evil in the traditions of the Early Modern Age mark the key milestones in the research of these categories in the transitional historical period.
Single-molecule surface-enhanced Raman spectroscopy (SM-SERS): characteristics and analysis
Authors: Zhao Xing , Hao Qi , Ni Zhen-Hua , Qiu Teng ,   School of Physics, Southeast University, Nanjing 211189, China,   Quantum Information Research Center, Southeast University, Nanjing 211189, China
Published: June 2021

Single-molecule detection (SMD), which represents the detection limit in molecular spectroscopy, has opened a new research realm in the fields of catalysis, DNA sequencing and protein analysis. Meanwhile, it provides new insights into the understanding of the molecule behaviors in a complex system. Specifically, SMD enables the quantitatively identifying of molecules accurate to single digit, provides the molecular distribution state under specific environments, and permits the in-situ observation of signal fluctuations of a single-molecule under chemical stimulus. Single-molecule surface-enhanced Raman spectroscopy (SM-SERS) is a new subject in SMD which features specific recognition of molecules by identifying the molecular chemical bonds. It is a non-destructive technology which reflects the vibration energy and rotational energy information of molecules. This technique employs metallic nanostructures to form surface plasmon resonances (SRP) under external excitation. The SPRs generate strong local electromagnetic fields ("hot spots") around metal surface to amplify the Raman signal of probe molecules in the vicinity of plasmonic materials. The giant field enhancement endows SERS superior sensitivity in trace molecule detection down to a single-molecule level. The SM-SERS offers a facile method to track the evolution of a single molecule, revealing the reaction pathways, adsorption state and distributions, and charge exchanges between the molecule and surrounding environment. Though SM-SERS has been proposed more than 20 years ago, the acquisition of SM-SERS spectra remains a bottleneck in this field due to the disability in judging the origins of these spectra. On the other hand, the lack of knowledge in analyzing SM-SERS spectra also limits the development of SM-SERS as the origins of molecule behavior at a micro level is basically unknown to the public. This review paper covers the development of SM-SERS, the past and current methods of verifying SM-SERS including the non-statistical and the bi-analyte statistical methods, the investigation into the understanding of the fluctuation characteristics of SM-SERS, as well as the related mechanisms with regard to the unique phenomena in SM-SERS such as molecule diffusion, spectral blinking and broadening. We hope this review can help the readers to relate the characteristics in SM-SERS with the origins of molecular variations during the detection, in this way to get a clear and in-depth understanding of the roadmap for SM-SERS.
Circular intuitionistic fuzzy TOPSIS method with vague membership functions: Supplier selection application context
Authors:   Istanbul Technical University, Industrial Engineering Department, Kahraman Cengiz , Alkan Nurşah ,   Istanbul Technical University, Industrial Engineering Department
Published: June 2021

The membership function of a general type-2 fuzzy set is three-dimensional in order to incorporate its vagueness through the third dimension. Similarly, Circular intuitionistic fuzzy sets (CIFSs) have been recently introduced by Atanassov (2020) as a new extension of intuitionistic fuzzy sets, which are represented by a circle representing the vagueness of the membership function. CIFSs allow decision-makers to express their judgments including this vagueness. In this study, the TOPSIS method, which is one of the most used multi-criteria decision-making methods is extended to its CIF version. The proposed CIF-TOPSIS methodology is applied to the supplier selection problem. Then, a sensitivity analysis based on criteria weights is conducted to check the robustness of the proposed approach. A comparative analysis with single-valued intuitionistic fuzzy TOPSIS method is also performed to verify the developed approach and to demonstrate its effectiveness
Risk Assessment of Poisonous Metals in Water and Soil at Two Abandoned Lead-Zinc Mines at Yonov, Benue State
Authors: Paul Samuel N. , Babatunde Bolaji B.
Published: June 2021

Aim: The study was aimed at determining the risk assessment of toxic metal concentration in soil and water at two abandoned Lead-Zinc mines Yonov District, Logo, Benue State, Nigeria.

Study design:  comparative cross-sectional study.

Place and duration of study: This study was carried out at the Bruce Powel Toxicology & Biodiversity Laboratory, Animal and Environmental Biology Department, University of Port Harcourt, Analysis at Giolee Global Services Limited Port Harcourt, Nigeria from 16th July to 30th October 2019.

Methodology: Eighteen composite water and soil samples were collected and analyzed using Atomic Absorption Spectrophotometer.

Results: The mean concentration of Lead (Pb) was higher than that of Zinc (Zn) in all eighteen samples, while, Mercury (Hg) and Cadmium (Cd) were below detection limit in all samples. Mean concentration for Pb in soil samples in the order SiteII>Site I (1.29±0.134 mg/kg>1.26±0.04mg/kg) >control 0.82±0.06 mg/kg. Zn was higher in site I, 0.70±0.10 mg/kg than site II 0.66±0.04mg/kg, and control 0.42±0.02mg/kg. Pb values in water was similar in both sites at 0.46±0.04/0.02 mg/L, while control 0.02±0.001mg/kg. Zn was higher in site II 0.05±0.01mg/L than site I 0.04±0.01Mg/L, control was 0.004±0.00 mg/L. Health risk assessment showed that Estimated daily intake of metals, hazard quotient, hazard index were all less than 1, Carcinogenic risk was within the stipulated ranged of 10-6 to 10-4.

Conclusion: Ecological and health risk indices revealed non-contamination by Poisonous metals, however, routine assessment is recommended to forestall any sudden change in the concentration that may result to deleterious effects on human health.
Trace Metals in Selected Fish Species from Five Cowries Creek, Southwest Nigeria: Consumer Safety Assessment
Authors: Balogun Kayode James , Kareem Kazeem Oladeji , Ajani Emmanuel Kolawole
Published: June 2021

This study aims to examine trace metals (Pb, Cd, Cr, Zn, and Cu) concentration in muscle tissues of four fish species from Five Cowries Creek and assess the safety risks posed by consuming these fish species. For this purpose, fish species such as Cynoglossus senegalensis, Mugil cephalus, Chrysichthys nigrodigitatus and Pseudotolithus typus were procured monthly from anglers in Five Cowries Creek, Lagos, from February to May, 2019. The fish muscle tissues were digested according to the international standards, and the trace metals were measured using an atomic absorption spectrophotometer (AAS). Results revealed that the ranking order of trace element concentrations followed this sequence: Pb > Cr > Zn > Cu > Cd. There were significant differences (P < 0.05) in Pb and Cr among the fish species. Consumer health risk was evaluated using non-carcinogenic and carcinogenic risk indices. The results showed that EDI and target hazard quotient (THQ) of Cr, Zn, Cu and Cd suggested that fish species consumption did not pose risk to consumer health. Nevertheless, the estimated daily intake (EDI) along with THQ of Pb indicated potential health risks to consumers (children and adult) of Chrysichthys nigrodigitatus. The target hazard index (THI) of trace elements in all investigated fish species exceeded the guideline value of 1, indicating an adverse health risk for exposed consumers. However, the carcinogenic risk of Pb was negligible for children and adult consumers of fish species. The results are anticipated to create alertness among the public on the safety risks as a result of consuming metal-contaminated fish. Authorised regulatory agencies should control the unregulated uses of Five Cowries Creek, Lagos and associated water bodies through the enforcement of various regulations, policies and laws.
Effect of Sodium Bicarbonate on Haematological Parameters and Differential Cells in Plasmodium Berghei-infected Albino Mice
Authors: Haruna G. S. , Enemali M. O. , Achimugu I. I. , Isah R. , Miftahu M.
Published: June 2021

The current study evaluated the hematological changes in albino mice following infection with P. berghei and treatment with sodium bicarbonate; an alkaline substance intended to alkalinize the pH in the parasite environment. Twenty albino mice were randomly divided into five groups of four mice each. Groups 3, 4 and 5 were the test groups and administered 84mg/kg b.w of sodium bicarbonate injection once, twice and thrice respectively. Groups 1 received dH20, group 2; only P. berghei. Three days later, hematological parameters and differential cells were analyzed. PCV was significantly (p<0.05) lower in groups 2(32.00±0.70), 3(34.00±0.70), 4(34.00±0.70), 5(33.00±0.70) compared to control (35.00±0.70). Haemoglobin decreased significantly (p<0.05) in group 5 (11.00±0.70) compared to control (11.80±0.70). WBC showed significant (p<0.05) increase in the test groups; 2(3600.00±70.71), 3(4600.00±70.71), 4(4800.00±70.71), 5 (4800.00±70.71) compared to control (3200.00±70.71). Platelets decreased significantly (p<0.05) in the test groups; 2(90.00±.70), 3(87.00±.70), 4(84.00±.70), 5(86.00±.70) compared to control (92.00±.70). The percentage neutrophils was significantly (p<0.05) higher in group 2(61.00±0.70), significantly (p<0.05) lower in groups 3(58.00±0.70), 4(57.00±0.70), 5(57.00±0.70) compared to control (60.00±0.70). Leucocytes increased significantly (p<0.05) in groups 2(36.00±0.70), 3(38.00±0.70), 4(38.00±0.70), 5(40.0±0.70) compared to control (32.00±0.70). Monocyte was significantly (p<0.05) lower in the test groups; 2(2.00±0.07), 3(2.00±0.07), 4(2.00±0.10) and 5(1.00±0.89) compared to control (4.00±0.07). Eosinophils decreased significantly (p<0.05) in group 2(1.00±0.35), increased significantly (p<0.05) in group 4(3.00±0.70) compared to control (2.00±0.70). Basophils were not detected in neither of the groups. This study revealed that sodium bicarbonate administered to albino mice infected with P. berghei caused the elevation of some hematological parameters and differential cells.
Effect of Precision Nitrogen Management through LCC on Nutrient Content and Uptake of Maize (Zea mays L.) under Temperate Conditions of Kashmir
Authors: Fayaz Suhail , Kanth Raihana Habib , Bhat Tauseef Ahmad , Bhat M. Anwar , Alie Bashir Ahmad , Dar Zahoor Ahmad , Mehdi Zaffar , Maqbool Showkat , Rasool Khalid
Published: June 2021

Field experiment was conducted at Faculty of Agriculture, SKUAST-Kashmir, Wadura, Jammu and Kashmir during kharif seasons of 2019 and 2020 to assess the effect of precision nitrogen management through LCC on nutrient content and uptake of maize (Zea mays L.) under temperate conditions of Kashmir. The experiment comprised of three maize hybrids (SMH-2, Vivek-45 and Kanchan-517) assigned to main plots and seven Precision N management viz. nitrogen splits @ 20 and 30 kg N ha-1 managed through LCC (LCC scores of 3, 4 and 5), recommended nitrogen level and control in subplots. The treatments were replicated thrice in a split plot design. The results revealed that LCC ≤ 5 @ 30 kg N ha-1 recorded highest dry matter accumulation and periodic N uptake at all the stages of growth and highest P and K uptake by grain and straw at harvest. Further, highest dry matter accumulation and uptake of NPK was recorded in cultivar SMH-2 as compared to Vivek-45 and Kanchan-517 during 2019 and 2020 respectively. LCC based N application proved effective in increasing dry matter and nutrient content of maize hybrids.
Response of Paddy Rice (Oryza sativa L.) Morphological Characteristics to Nitrogen Fertilizers in Taveta, Kenya
Authors: Chawana Isaac Righa , Gacheru James , Maghenda Marianne , Maghanga Justin , Kambura Anne Kelly , Kimani John , Mcharo Mwamburi
Published: June 2021

This study investigated the effect of applying nitrogenous fertilizers on the morphological traits in six paddy rice varieties in Taveta, Kenya. The six paddy rice varieties, including local control, were tested during the 2018 and 2019 seasons. The experiments were laid out in a split-plot design with three replications. The main plot was the fertilizer treatment while the subplot was the varieties tested including NIBAM-11, K2-9, MWIR-2, R-1081, Silewa, and a local control Saro. The fertilizer treatments were no fertilizer, farm yard manure (FYM) alone, FYM+Urea fertilizer, and FYM+CAN fertilizer. Significant differences (P < 0.05) among varieties were observed for all the morphological traits that were assessed. Silewa was the tallest plant (111 cm), had the highest number of grains per panicle (163), and also the highest 1000-grain weight (29.2 g). Fertilizer treatments had significant effects on plant height, leaf length, number of tillers, panicle length, and number of grains per panicle. FYM+Urea resulted in the highest number of grains per panicle while FYM alone resulted in the highest 1000- grain weight (25.56 g). Varieties significantly interacted with fertilizers for the number of grains per panicle. Leaf length had significant direct association with 1000-grain weight (r = 0.427) and grains per panicle (r = 0.874). It can be recommended that there is an opportunity to use farm yard manure alone or in combination with an inorganic fertilizer to improve yield traits while reducing dependence on inorganic fertilizers.
Extended Ensemble Filter for High-dimensional Nonlinear State Space Models
Authors: Robert Oryiema , Angwenyi David , Midenyo Kevin
Published: June 2021

There are several functional forms for non-linear dynamical filters. Extended Kalman filters are algorithms that are used to estimate more accurate values of unknown quantities of internal dynamical systems from a sequence of noisy observation measured over a period of time. This filtering process becomes computationally expensive when subjected to high dimensional data which consequently has a negative impact on the filter performance in real time. This is because integration of the equation of evolution of covariances is extremely costly, especially when the dimension of the problem is huge which is the case in numerical weather prediction.This study has developed a new filter, the First order Extended Ensemble Filter (FoEEF), with a new extended innovation process to improve on the measurement and be able to estimate the state value of high dimensional data. We propose to estimate the covariances empirically, which lends the filter amenable to large dimensional models. The new filter is derived from stochastic state-space models and its performance is tested using Lorenz 63 system of ordinary differential equations and Matlab software.The performance of the newly developed filter is then compared with the performances of three other filters, that is, Bootstrap particle Filter (BPF), First order Extended Kalman Bucy Filter (FoEKBF) and Second order Extended Kalman Bucy Filter (SoEKBF).The performance of the FoEEF improves with the increase in ensemble size. Even with as low number of ensembles as 40, the FoEEF performs as good as the FoEKBF and SoEKBF. This shows, that the proposed filter can register a good performance when used in high-dimensional state-space models.
Determinants of Immunization Completeness among Children Aged 12-23 Months in South-West Nigeria
Authors: Olarinmoye Abayomi , Eniade Olanrewaju Davies , Enyinnaya Blessing O , Olasunkanmi Yusuff Akinkunmi , Nwaneri Blessing Chizorom , Eniade Adenike Aramide , Agbojo Uriel Oluwadarasimi , Afolabi Divine Wonuola , Kayode Bode
Published: June 2021

Introduction: Vaccine preventable disease remained issue of major concern to the global health system. Low coverage of immunization necessitated the need to explore the determinants of immunization uptake. Factors influencing immunization coverage in South-West Nigeria were investigated in this study.

Methods: Data from the Nigeria demographic and health survey (NDHS) was used for this study. Our focus was on children between 12 to 23 months whose parents were residents of South-West Nigeria. A total of 655 records were used for the analysis of this study. The outcome variable (child’s immunization status) was categorized as “non-or- under immunized and fully immunized”. Considered explanatory variables were children and parents’ characteristics.

Data were analyzed using Statistical package for social sciences (SPSS) version 25. Descriptive statistics were presented and generalized linear model was used to explore the determinants of immunization completeness.

Results: Of the 665 children whose mean age was 16.7 ± 3.4 SD months, 62.3% were non-or-under immunized, while only 79.8% were birthed in the health facility. Majority of them (65.1%) were not presented for postnatal check within two months of birth while 51% do not have health card. About 79% of the mothers said distance to the health facility was not a problem. In this study, postnatal check within 2 months of birth, type of residence and ownership of health card were identified factors influencing the uptake of immunization. For instance, Those who said distance is a problem were 3 times less likely to fully immunize their children (AOR=0.28, p=0.000, 95% CI: 0.16-0.47). Obviously, ownership of health card (AOR=15.34, p=0.000, 95% CI: 9.86-23.88) and postnatal check within 2 months of birth (AOR=1.78, 95% CI: 0.37-0.86) were associated with the likelihood of complete immunization.

Conclusion: Immunization uptake was very low in South-West Nigeria. Factors that were positively associated with completeness of immunization include observance of postnatal check and ownership of healthcare card while problem of distance to health facility was negatively associated. Increasing vaccination coverage/ completeness would ameliorate, if policy geared towards the improvement of postnatal check-ups, distribution of healthcare facilities within residential areas and strict adherence to the use of health care are considered in the South-West Nigeria.
Cannabis use linked to increase in suicidality, especially in women: NIDA
Authors: Knopf Alison
Published: June 2021

Cannabis use is associated with three types of suicidality in young adults: suicidal ideation (thoughts of suicide), suicide plans and suicide attempts, according to a recent study by researchers from the National Institute on Drug Abuse (NIDA) published in JAMA Network Open online June 22. The associations could not be proven causally, but the 40–60% increase in suicidality — ideation, plan, attempt and death — mirrors the increase in cannabis use.
HRSA announces student loan replacement grants program
Authors: Knopf Alison
Published: June 2021

A new program offering up to $250,000 in student loan replacement is now available for substance use disorder (SUD) treatment professionals who work in areas with high overdose rates, or with a low number of mental health professionals.
Influence of Gradient Residual Stress and Tip Shape on Stress Fields Inside Indented TiN Hard Coating
Authors: Todt Juraj , Zalesak Jakub , Krywka Christina , Keckes Jozef
Published: June 2021

Nanoindentation of treated surfaces, thin films, and coatings is often used as a simple method to measure their hardness and stiffness. These quantities are technologically highly relevant and allow to qualitatively compare different material and surface treatments but fail to capture the entire extent of the highly complex mechanical interaction between indenter tip and the tested surface. Many studies have addressed this question by analytical or numerical modeling, but they must rely on verification by recalculating indentation curves or ex situ microscopy of surface deformation postexperiment. Herein, results from in situ measurements of the multiaxial stress distributions forming beneath an indenter tip while the tested sample is still under load are presented. A 9 μm‐thick TiN hard coating is tested in 1) as‐deposited state and 2) shot‐peened by Al2O3 particles, using two diamond wedges as indenter tips, with 60° and 143° opening angle, respectively. The results reveal a strong influence of the tip shape on the deformation behavior and the main stress component developing inside the sample while under load. In addition, a crack‐closing effect can be attributed to the exponentially declining near‐surface compressive residual stress gradient that is present in the shot‐peened sample.
Nanostructured Oxide‐Dispersion‐Strengthened CoCrFeMnNi High‐Entropy Alloys with High Thermal Stability
Authors: Zhang Xiang , Wang Fei , Yan Xueliang , Li Xing-Zhong , Hattar Khalid , Cui Bai
Published: June 2021

A nanostructured oxide‐dispersion‐strengthened (ODS) CoCrFeMnNi high‐entropy alloy (HEA) is synthesized by a powder metallurgy process. The thermal stability, including the grain size and crystal structure of the HEA matrix and oxide dispersions, is carefully investigated by X‐ray diffraction (XRD) and electron microscopy characterizations after annealing at 900 °C. The limited grain growth may be attributed to Zener pinning of yttria dispersions that impede the grain boundary mobility and diffusivity. The high hardness is caused by both the fine grain size and yttria dispersions, which are also retained after annealing at 900 °C. Herein, it is implied that the combination of ODS and HEA concepts may provide a new design strategy for the development of thermally stable nanostructured alloys for extreme environments.
A Focus on “Bio” in Bio–Nanoscience: The Impact of Biological Factors on Nanomaterial Interactions
Authors: Cortez‐Jugo Christina , Czuba‐Wojnilowicz Ewa , Tan Abigail , Caruso Frank
Published: June 2021

Bio–nanoscience research encompasses studies on the interactions of nanomaterials with biological structures or what is commonly referred to as the biointerface. Fundamental studies on the influence of nanomaterial properties, including size, shape, composition, and charge, on the interaction with the biointerface have been central in bio–nanoscience to assess nanomaterial efficacy and safety for a range of biomedical applications. However, the state of the cells, tissues, or biological models can also influence the behavior of nanomaterials at the biointerface and their intracellular processing. Focusing on the “bio” in bio–nano, this review discusses the impact of biological properties at the cellular, tissue, and whole organism level that influences nanomaterial behavior, including cell type, cell cycle, tumor physiology, and disease states. Understanding how the biological factors can be addressed or exploited to enhance nanomaterial accumulation and uptake can guide the design of better and suitable models to improve the outcomes of materials in nanomedicine.
Biocompatible Polymer and Protein Microspheres with Inverse Photonic Glass Structure for Random Micro‐Biolasers
Authors: Ta Van Duong , Caixeiro Soraya , Saxena Dhruv , Sapienza Riccardo
Published: June 2021

The miniaturization of random lasers to the micrometer scale is challenging but fundamental for the integration of lasers with photonic integrated circuits and biological tissues. Herein, it is demonstrated that random lasers with a diameter from 30 to 160 μm can be achieved by using a simple emulsion process and selective chemical etching. These tiny random laser sources are made of either dye‐doped polyvinyl alcohol (PVA) or bovine serum albumin (BSA) and they are in the form of microporous spheres with monodisperse pores of 1.28 μm in diameter. Clear lasing action is observed when the microporous spheres are optically excited with powers larger than the lasing threshold, which is 154 μJ mm−2 for a 75 μm diameter PVA microporous sphere. The lasing wavelength redshifts 10 nm when the PVA microsphere diameter increases from 34 to 160 μm. For BSA microspheres, the lasing threshold is around 55 μJ mm−2 for a 70 μm diameter sphere and 104 μJ mm−2 for a 35 μm diameter sphere. The simple fabrication process reported allows for detail studies of morphology and size, important for fundamental studies of light–matter interaction in complex media, and applications in photonic integrated circuits, photonic barcoding, and optical biosensing.
Self‐Reporting Hydrogel Sensors Based on Surface Instability‐Induced Optical Scattering
Authors: Frenkel Imri , Hua Mutian , Alsaid Yousif , He Ximin
Published: June 2021

Interest regarding the development of hydrogel sensors continues to grow due to the associated high sensitivity, fast response, low fabrication cost, and versatile application when responding to an analyte. The strategies for transducing these responses range from electrochemical to optical, often utilizing characterization equipment to measure the minute changes in the material. However, the costly nature of such equipment counteracts the original advantages of utilizing a hydrogel‐based sensor, rendering the overall system slow and inaccessible for many. Therefore, hydrogel sensors capable of self‐reporting values to the naked eye are needed. Here, a new light‐scattering‐based transduction method is explored—indiscriminately visible to the naked eye. By engineering the surface instability behavior of a hydrogel film, an exemplary design is developed using an anionic, pH‐responsive poly(acrylamide‐co‐acrylic acid) hydrogel to self‐report the pH via subsequent buckling (i.e., its scattering of light). By modeling the behavior based on three system parameters (critical concentration, critical swelling ratio, and modulus), a general design model is produced to guide practical implementations of this instability‐induced scattering (IIS) sensor system. The viability of the IIS design model is exemplified through a proof‐of‐concept application to sensing urea, illustrating the modular and adaptable design of the presented transduction method.
Optically Transparent Graphene Flakes as Nanogenerator of Microbubbles for Random Lasing in Weakly Scattering Regime
Authors: Pramanik Ashim , Biswas Subrata , Dey Arindam , Kumbhakar Pathik
Published: June 2021

The minimization of photon loss is one of the significant challenges in designing efficient random lasers (RLs). Herein, the demonstration of a 4‐(dicyanomethylene)‐2‐methyl‐6‐(4‐dimethylaminostyryl)‐4H‐pyran (DCM) dye‐based RL is made by the employment of an innovative adaptive feedback mechanism through the use of a fundamental phenomenon of total internal reflection of light in the microbubbles, generated photothermally in the presence of graphene flakes (GFs). Interestingly, here, GFs have acted simultaneously as passive scatterer and thermocatalyst for in situ generation of microbubbles in the liquid suspension of dye molecules. It is demonstrated by a simple pump‐probe photography experiment that during RL emission, the transport of photons is occurring via weak scattering in GFs followed by total internal reflection on microbubbles. Thus, RL emission at 638.4 nm is achieved with a low lasing threshold, linewidth, and moderately high quality factor of 84 W cm−2, 2 nm, and 1127, respectively. The performances of GFs in RL generation are found to be superior in comparison with those of spherical TiO2 and Ag nanoparticles. The strategy is a contemporary approach for applying a 2D material as a nanogenerator of microbubbles to achieve improved RL emission in the weakly scattering regime using an adaptive feedback approach.
Compact High‐Power Visible Laser Diode Wavelength Division Multiplexing for White‐Light Communication
Authors: Su Chia-Yu , Wang Huai-Yung , Cheng Chih-Hsien , Lin Gong-Ru
Published: June 2021

For compact ultrahigh‐power lighting and high‐speed optical wireless communication (OWC) purposes, the red/green/violet laser diodes (R/G/V‐LDs) moduled with specific Subminiature A (SMA) connectors are used for cold white‐light mixing and direct digital encoding. Even with hybridizing a high‐power yellow light‐emitting diode (LED) for high color‐rendering index lighting, such a R/G/V/Y design can miniaturize its volume to W × L × H = 6 × 5.4 × 2 cm3 (only 1/310 of the conventional bulky setup). The R/G/V‐LDs are individually encoded by 16 quadrature amplitude modulation orthogonal frequency‐division multiplexing (16‐QAM OFDM) data to demonstrate the visible wavelength division multiplexing (VWDM). Such R/G/V‐LD VWDM transmitters provide 8.8/5.2/7.2 Gbps modulation to achieve the total data rate as high as 21.2 Gbps after employing the power preleveling technique. Such high‐power R/G/V‐LDs under optimized bias currents deliver an output power of 102/97/129 mW, which can offer a high illuminance of 12 800 lux within a divergent angle of 54° at a distance of 0.5 m. To date, such ultrahigh‐power compact R/G/V‐LDs with lighting VWDM capability beyond 20 Gbps also enable the possibility of network coverage for B5G/6 G and Industry 4.0 applications.
Synthesis of 2‐Alkenyl‐4H‐3,1‐Benzoxazin‐4‐Ones through HFIP‐Mediated Decarboxylative [4+2]‐Annulation of Isatoic Anhydrides with Cyclopropenones under Silver Catalysis
Authors: Yang Mengqi , Wang Jixin , Lv Weiwei , Ba Dan , Cheng Guolin , Wang Lianhui
Published: June 2021

We herein describes an HFIP‐mediated [4+2]‐cycloaddition reaction from simple and easily available isatoic anhydrides and cyclopropenones under silver catalysis. This transformation involves the tandem decarboxylative esterification, intermolecular addition, intramolecular substitution, small ring opening and isomerization processes, which allows the rapid assembly of versatile 2‐diarylalkenyl‐4H‐3,1‐benzoxazin‐4‐ones.

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A Donor Polymer with a Good Compromise between Efficiency and Sustainability for Organic Solar Cells
Authors: Penconi Marta , Bianchi Gabriele , Nitti Andrea , Savoini Alberto , Carbonera Chiara , Pasini Dario , Po Riccardo , Luzzati Silvia
Published: June 2021

Impressive advancements in solution‐processed bulk heterojunction (BHJ) solar cells have been driven to a large extent by the rational design of conjugated polymers as photoactive donors. These achievements have been obtained without paying much attention to green metrics parameters (such as E factor) and to the increasing synthetic complexity (SC), which is a bottleneck for industrial scalability. In this context, a novel donor copolymer (PBDT3T) based on benzodithiophene and terthiophene building blocks with ester functionalities is synthesized. The 26‐fold‐reduced E factor for the benzodithiophene monomer synthesis and the SC index of 24 for PBDT3T, much lower compared with benchmark donor polymers, provide a hint for good scalability, sustainability, and low costs. PBDT3T features a relatively wide optical bandgap and a deep highest occupied molecular orbital (HOMO), meeting the requirements for suitable donor material in both fullerene and nonfullerene‐based solar cells. PBDT3T is studied in binary and ternary blend, using PC71BM and ITIC as acceptors. The best performances are obtained in the ternary blend devices, reaching power conversion efficiency (PCE) values of 7.14%. Trade‐off considerations between PCE and SC make PBDT3T promising on an industrial perspective.
Motion cues increase focused attention towards purely visual stimuli in a nocturnal primate and drive stimulus interaction and approach/avoidance in a context‐dependent manner
Authors: Hartje Valeria , Illemann Michele J. , Schmidtke Daniel
Published: June 2021

Visual information is of pivotal ecological importance to monkeys, apes, and humans, whereas its role in nocturnal primate ecology is less well understood. We explored how purely visual information modulates the behavior of a nocturnal primate. Abstract (shape), photographic (shape + detail), or video (shape + detail + motion) representations of arthropod prey (Zophobas morio; food context) or a male conspecific (social context) were systematically presented to 22 individuals of the gray mouse lemur (Microcebus murinus) using a touchscreen. We assessed stimulus‐directed touch interactions, durations of focused visual attention towards the different stimuli, and durations spent in the half of the setup‐chamber more distant to the touchscreen (as quantification of approach/avoidance). Focused attention towards the stimulus generally increased from abstract and photographic to videographic stimuli. For the food context, indications for a parallel increase in stimulus‐directed touch interactions from abstract stimulus to video were found. Approach/avoidance was independent of the stimulus type within both contexts. A comparison between the contexts under the video condition revealed higher durations of visual attention and lower stimulus avoidance in the food context compared to the social context. The number of touch interactions with the video stimulus was not generally context‐dependent, but context‐dependency related to sex: In the food context, animals with high and low numbers of touch interactions were equally distributed across sexes. In the social context, females showed the highest numbers of touch interactions. Numbers in males declined compared to the food context. Our results demonstrate for the first time that purely visual information modulates mouse lemur behavior and focused attention in a content‐ and context‐specific manner, suggesting that vision is of high importance for the ecology of these nocturnal primates. The findings emphasize the need for further vision‐based experiments to gain deeper insight into the evolution of visual information processing and cognition in nocturnal primates.
Thiophene‐Based Conjugated Acetylenic Polymers with Dual Active Sites for Efficient Co‐Catalyst‐Free Photoelectrochemical Water Reduction in Alkaline Medium
Authors: Borrelli Mino , Querebillo Christine Joy , Pastoetter Dominik L. , Wang Tao , Milani Alberto , Casari Carlo , Khoa Ly Hoang , He Fan , Hou Yang , Neumann Christof , Turchanin Andrey , Sun Hanjun , Weidinger Inez M. , Feng Xinliang
Published: June 2021

Although being attractive materials for photoelectrochemical hydrogen evolution reaction (PEC HER) under neutral or acidic conditions, conjugated polymers still show poor PEC HER performance in alkaline medium due to the lack of water dissociation sites. Herein, we demonstrate that tailoring the polymer skeleton from poly(diethynylthieno[3,2‐b]thiophene) (pDET) to poly(2,6‐diethynylbenzo[1,2‐b:4,5‐b′]dithiophene (pBDT) and poly(diethynyldithieno[3,2‐b:2′,3′‐d]thiophene) (pDTT) in conjugated acetylenic polymers (CAPs) introduces highly efficient active sites for water dissociation. As a result, pDTT and pBDT, grown on Cu substrate, demonstrate benchmark photocurrent densities of 170 μA cm−2 and 120 μA cm−2 (at 0.3 V vs. RHE; pH 13), which are 4.2 and 3 times higher than that of pDET, respectively. Moreover, by combining DFT calculations and electrochemical operando resonance Raman spectroscopy, we propose that the electron‐enriched Cβ of the outer thiophene rings of pDTT are the water dissociation active sites, while the −C≡C− bonds function as the active sites for hydrogen evolution.
Highly active cobalt complex catalysts used for alkene hydrosilylation
Authors: Liu Yu , Li Jiayun , Bai Ying , Peng Jiajian
Published: June 2021

A series of nitrogen phosphine ligands were synthesized, and the hydrosilylation reaction of alkenes catalyzed using MCl2 in the presence of these ligands was investigated. FeCl2/1(N1, N1, N2, N2‐Tetrakis[(diphenylphosphino)methyl]ethane‐1,2‐diamine) showed low catalytic activity. MnCl2/1, CrCl3/1 and NiCl2/1 showed some catalytic activity. The CoCl2/N,P‐ligand catalyst system showed high activity as well as excellent selectivity (The selectivity of the β‐adduct was ~100%.) in the hydrosilylation reaction. CoCl2/1 showed the highest catalytic activity (~ >99.9% conversion of 1‐octene). Additionally, no α‐adduct, dehydrogenative silylation product and octane were detected.
Synthesis and characterization of [4‐{(CH2O)2CH}C6H4]2Hg, [4‐(O=CH)C6H4]2Hg and [(E)‐4‐(RN=CH)C6H4]2Hg (R = 2′‐py, 4′‐py, 2′‐pyCH2, 4′‐pyCH2)
Authors: Kiss Levente , Pop Alexandra , Shova Sergiu , Raț Ciprian I. , Silvestru Cristian
Published: June 2021

The reaction of 4‐[(CH2O)2CH]C6H4Br (1) with n‐BuLi, followed by addition of HgCl2 to the in situ formed organolithium derivative, affords [4‐{(CH2O)2CH}C6H4]2Hg (2). Deprotection of the formyl groups of 2 in presence of p‐TsOH (p‐Ts = 4‐MeC6H4SO3) leads to [4‐(O=CH)C6H4]2Hg (3). Condensation reactions of 3 with 2‐aminopyridine (2‐pyNH2), 4‐aminopyridine (4‐pyNH2), 2‐aminomethylpyridine (2‐pyCH2NH2), and 4‐aminomethylpyridine (4‐pyCH2NH2), in CH2Cl2, affords the novel diorganomercury(II) compounds of type [(E)‐4‐(RN=C)C6H4]2Hg [R = 2′‐py (4), 4′‐py (5), 2'‐pyCH2‐ (6), 4′‐pyCH2 (7)]. Compounds 2 and 3 were useful precursors for the preparation of the corresponding homocoupling products [4‐{(CH2O)2CH}C6H4]2 (8) and [4‐(O=CH)C6H4]2 (9) in presence of catalytic amounts of palladium(II) acetate. Compounds 2–9 were characterized by multinuclear magnetic resonance (NMR) (1H, 13C{1H}, and 199Hg{1H}, when appropriate) and infrared (IR) spectroscopy and by mass spectrometry. The molecular structures of 3, 5, 6, 8, and 9 were determined by single‐crystal X‐ray diffraction.