bluuebunny/crossref_metadata_2025 huggingface dataset:
Voice Recognition System for Door Access Control Using Mobile Phone
Authors: Samuel Falohun Adeleye , Titilayo Adedeji Oluyinka , Abiodun Adegbola Oluwole , Modupe Alade Oluwaseun , Oyeladun Makinde Bukola , Mayowa Isamot Rokeeb , Samuel Ajadi Mayowa
Published: September 2021

Security is one of the most important issues for any individual or organization, and as technology has advanced, numerous techniques to protecting lives and property have been deployed through door access control systems. The typical method of unlocking a door is to open it with a real key or by twisting the door knob. Physical keys that are used to open doors are subject to duplication and can be misplaced. Furthermore, typical biometric technologies and other technologies are vulnerable to a variety of failures, such as a person's finger being cut off to produce a fingerprint scan, a pin being hacked using various methods or permutations, and a person's photo being used for facial recognition. Furthermore, it is more difficult for people with physical disabilities to unlock a door system without the assistance or support of others. For example, it is difficult for a person in a wheelchair to open a door system without the assistance or support of another person. As a result, a speech recognition access control system that can accommodate both able-bodied and impaired people is unavoidable. This paper demonstrates how voice recognition may be used to access door systems by creating a door access control system that employs speech recognition to simplify the work of providing access to door systems via a mobile phone connected via Bluetooth. The system's performance is perfectly in line with its design.
КУДА ИСЧЕЗЛИ РИМЛЯНЕ ПОСЛЕ 476 ГОДА?, "Средние века"
Authors: Филиппов И.С.
Published: September 2021

Статья посвящена вопросу о том, почему в современной историографии так мало говорится о судьбе римского общества и римлян как этноса и носителей определенного языка и определенной культуры после падения Западной Римской империи, когда римляне утратили свою государственность. Под этим углом зрения рассматривается ситуация в основных национальных школах медиевистики: немецкой, французской, итальянской, испанской, английской, американской, недавно оформившейся австрийской и в российской школе, которой уделено особое внимание. Применительно к каждой из них автор исследует научные традиции, обусловившие такое положение вещей, а также влияния на историографию, идущие из общественной жизни. В заключении к статье предлагаются возможные пути изучения римского общества после 476 г., с учетом состояния источников и реалий раннесредневековой истории.
Promoting and Enhancing Effective Teacher Professional Development in Tanzania: Lessons from Chinese Teacher Professional Development
Authors: Lyanga Amani Abisai
Published: September 2021

This paper reports on promoting and enhancing effective teacher professional development in Tanzania: Lessons from Chinese teacher professional development. Teacher professional development is an important aspect in any country for educational achievement. In several years Tanzania has been facing ineffective teacher training and professional development. As a result, most of the teachers fail to plan their professional development as it expected to be. The analysis of findings indicated that Chinese teacher professional development has obtained significant achievement due to the presence of a strong policy, heavy investment in the teacher education sector, and other related factors. In this regard, these lessons are worth to Tanzania which still struggling to have effective teacher professional development through teacher practice. Therefore this study recommended that the Tanzanian government should encourage professional training programs for teachers through financial and material support.
Effects of Hydroethanolic Extract of Adenia lobata (Jacq.) Engl. (Passifloraceae) on Nociception and Subsequent Anxiety-like Behavior: Both Anti-inflammatory and Antioxidant Approaches
Authors: N’Go Pacôme Kouadio , Tehoua Lazare , Bolou Eric-Kevin Gbouhoury , Touré Aicha Salamentou , Tako Antoine Némé
Published: September 2021

Aims: Adenia lobata (Jacq.) Engl. (Passifloraceae) is widely used in Ivorian traditional pharmacopeia to heal various chronic diseases, relieve headache and pain of gingiva inflammation, and facilitate labor. Here, we investigated the effects of hydroethanolic extract Adenia lobata (HEAL) on nociceptive pain and subsequent anxiety-like behavior.

Materials and Methods: We used several experimental pain tests as the writhing, formalin and hot plate to evaluate both antinociceptive and anti-inflammatory actions of the extract. Anxiety related to nociception was tested with open field and elevated plus maze tests. Then, mice were sacrificed for assessing some oxidative stress markers.   

Results: The extract of 30 mg/kg, p.o. reduced in the similar manner as reference peripheral drug salcylicacetic acid (ASA, 200 mg/kg, i.p.) the number of writhings induced by acid acetic. In both neurogenic and inflammatory phases of formalin test, the extract demonstrated an effective antinociceptive activity than ASA, but comparable to central analgesic tramadol (50 mg/kg, i.p). However, Adenia lobata reduced lesser thermal-induced pain than tramadol in hot plate test, but significantly compared to ASA. Furthermore, HEAL altered anxiety-like behavior in each case of the pain condition studied. Also, the extract showed the highest antioxidant activity by reduction oxide nitric (NO) and malondialdehyde (MDA), and increase non protein thiol (NP-SH) levels.    

Conclusion: In conclusion, HEAL possesses antinociceptive and anti-inflammatory actions on peripheral and central mechanisms of pain. The phytochemicals components of the extract as alkaloids and flavonoids suggest to interact with the opioid system and combat the oxidative stress, respectively. Our findings provide scientific basis for the use of Adenia lobata in traditional medicine against pain and related diseases.
Diversity of Filamentous Molds Producing Mycotoxins in Rice Called "Deni Kachia" Sold on the Markets of Daloa (Côte d’Ivoire)
Authors: Kouassi Kra Athanase , Ehouman Ano Guy Serge , Kouassi Kouassi Clément , Konate Ibrahim
Published: September 2021

Filamentous fungi are frequent contaminants of many plant substrates and certain animal products. Their presence can improve the organoleptic quality of the product or alter it and lead to the accumulation of toxic secondary metabolites, such as mycotoxins. The objective of this work is to characterize the filamentous fungi isolated from the rice "deni kachia" stored and sold on public markets in the city of Daloa. A count and isolation of filamentous fungi, followed by macroscopic and microscopic identification was carried out. Several genera of filamentous fungi was identified. These are the genera Aspergillus, Penicillium and others. The different species of molds identified by conventional biochemical techniques were confirmed by the API 50 CH freezer.The genera Aspergillus and Penicillium are the most predominant in the samples analyzed. The presence of these species with their ability to produce mycotoxins suggests that contaminated rice poses a risk to the health of consumers.
Mathematical Modeling of Treatment Effect on Tumor Growth and Blood Flow through a Channel with Magnetic Field
Authors: Bunonyo K. W. , Amadi C. U.
Published: September 2021

In this research, we investigated the effect of tumor growth on blood flow through a micro channel by formulated the governing model with the assumption that blood is an incompressible, eclectrially conducting fluid which flow is caused by the pumping action of the heart and suction. The governing model was scaled using some dimensionless variables and the region of the tumor was obtained from Dominguez [1] which was incorporated in our model. The model is further reduced to an ordinary differential equation using a perturbation condition. However, the ordinary differential equation was solved using method of undermined coefficients, and the constants coefficients obtained via matrix method. Furthermore, the simulation to study the effect of the pertinent parameters was done suing computation software called Mathematica. It is seen in our investigation that the entering parameters such as magnetic field parameter, the Reynolds number, womersley number, oscillatory frequency parameter, and permeability parameter affect the blood velocity profile in decreasing and increasing fashion.
Anti-Mullerian Hormone (AMH) Level in Presence of Ovarian Endometrioma
Authors: Radwan Nesma F. , Khyat Ahmed M. El , Gergawy Adel E. El , Salem Hesham A.
Published: September 2021

Background: The effect of endometriomas itself on the ovarian responsiveness that relate to ovarian reserve had been reported with several inconsistent results. In one study evaluated women with unilateral endometriomas, ovaries with disease showed lower response to ovarian stimulation than contralateral healthy ovaries .However, recent study on infertile women with un-operated unilateral small endometriomas did not support difference in ovarian responsiveness. The aim was to evaluate the impact of presence of endometriomas on ovarian reserve as measured by circulating AMH.

Methods: This retrospective study was carried out on 80 female patients in childbearing period attending outpatient clinic and/or inpatient department of obstetrics and gynecology at Tanat University Hospital and the study was conducted directly after approval in the period from Apri, 2019 till April 2020.

Group (A): Study group: 60 female patients aged between 20 to 30 years old

GROUP (B): Control group: 20 age matched female with healthy ovaries.

Results: there is no statistical significant difference between groups as regard Menarche (years), Regularity and Amount of menstrual blood flow. There is statistical significant difference between groups as regard fixed tender Right Ventricular Failure. But there are no statistical significant differences between groups as regard nodule in rectovaginal septum, fixed tender adnexal masses, association with adenomyosis and infertility. There is highly statistical significant difference between case and control groups as regard AMH levels. there are highly statistical significant positive correlation between duration of endometriosis and each of presence of pelvic pain, cyst diameter and Visual Analogue Scale.

Conclusions:    Women with endometrioma have significantly lower serum AMH levels and seem to experience a more rapid decline in serum AMH levels than age matched counterparts, suggesting a harmful effect of endometrioma per se on ovarian reserve.
The Effects of Tax Education on Government Revenue Collection: The Case of Small and Medium Enterprises in Morogoro Municipality, Tanzania
Authors: Ndubula Ezra , Matiku Emmanuel
Published: September 2021

The efficient and effective tax education to SMEs in developing countries like Tanzania is critical to overcome the challenges of tax compliances. Despite the trend of tax reforms in Tanzania since 1998, the effects of tax education on Small and Medium Enterprises (SMEs) are still poor and many SMEs still see taxation process and cost as constraints to SMEs’ successes (Adam, 2012; Masanja, 2019).

The study employed deductive approach, exploratory and descriptive survey methodology. The respondents involved 96 SMEs owners of Morogoro Municipality and four (4) TRA Education Department employees. The data collection tools involved the use of purposeful distributed questionnaires and interviews. The Statistical Package for Social Sciences (SPSS) was used to analyze data. The scope was to produce the frequency tables (Kothari, 209; Mbalwowa, 2014).

To determine if the provision of tax education has resulted in tax compliance among SMEs, the results shown that to large extent there were high level of incompliancy on: timeliness for tax payment, voluntary tax payment, use of EFDs, issuance of fiscal receipts and online filing of tax returns. Therefore, the main attributing factors of tax incompliancy have been associated with tax education.

The study recommends: to evaluate the tax education programs on revenue collection, complements information technology to disseminate tax education, carry out relational or causal studies of tax education on tax compliances across different demographic characteristics in Tanzania. More importantly, to promote a shift from the tax being assessed by TRA to self-tax assessment among SMEs through tax education program.
Optimal Placement of Capacitor Bank on Ondo 132/33KV Transmission Substation
Authors: Adetunmbi A. O. , Ebinowen T. D. , Oyediji F. T. , Adetunji A. A.
Published: September 2021

Introduction: Relevancies of electrical power system to consumers cannot be overemphasized. This requires healthy operation of such system. 132/33KV network is an important network within the transmission system and its importance calls for effective and efficient operation. However, due to the long distance at which the transmission line span, the nature of the lay (either overhead or underground) and type of cable used, there are series of voltage instability and power loss along the transmission network which are threat both economically and technically to both electricity providers and consumers because of the cost implication of the losses and effect on the stability of the network.

Aims: This research aims is to seek optimal placement of a capacitor bank to proffer solution to both voltage instability and power loss problem by simulating Ondo 132/33KV transmission network using NEPLAN software.

Methodology: The network model was developed using NEPLAN software. The voltage profile and power loss with and without capacitor bank were determined from power load flow solutions using Newton-Raphson method.

Results: Effects of optimal placements of capacitors along the studied transmission line is established.

Conclusion: Proper installation of capacitor bank is also found to enhance performance with an accompanied improvement in voltage profile along the buses.
Eucalyptus Pulp Fibers with In-Situ Precipitated Calcium Carbonate – A 12-Inch Laboratory Paper Machine Study
Authors: Dölle Klaus , Bajrami Bardhyl
Published: September 2021

Paper manufacturing on a global scale is a highly competitive market which requires to constantly improve the manufacturing process to be competitive. To decrease production cost paper manufactures, add filler material prior to sheet forming to replace costly wood fiber based raw material.

This research project investigates the use of in-situ precipitated calcium carbonate produced in the presence of eucalyptus fiber material at a 41.0% filler level prior to beating. The in-situ filler containing eucalyptus fiber suspension was used on a 12’ (304mm) wide Laboratory Fourdrinier Paper Machine together with non-filler containing eucalyptus fiber material, and a commercial precipitated calcium carbonate filler material.

The manufactured in-situ fiber suspension resulted in a higher ash retention compared to the addition of the powdered commercial PCC filler material. In addition to commercial filler material retention is improved at higher filler addition above 30%.

The increased ash retention is linked to the increased micro fibrillation fiber material of the in-situ filler-fiber suspension forming neckless like particles on the fibers microfibrils.

Mechanical paper properties showed an improvement for in-situ precipitated filler material compared to commercial filler material addition.

Optical properties could be improved in comparison to the eucalyptus fiber without filler addition for in-situ precipitated filler material and a combination of in-situ and commercial filler material.
Evaluation of Effectiveness of Chronic Care Model on Smokeless Tobacco Cessation by Measuring Urinary Cotinine Level among the Patient Attended in the Selected Dental College & Hospital, India -An Experimental Study
Authors: Rao Sakshi , Raut Pooja , Agrawal Riya , Chhabra Kumar Gaurav , Madhu Priyanka Paul , Reche Amit
Published: September 2021

Background: Smokeless tobacco is one of the most common causes of preventable death. It is a big social and health issue. Smokeless tobacco utilization is a significant cause of morbidity and mortality in India, with more than 20% of the world's tobacco-related mortality occurring in India. The Chronic Care Model is a guide for the principal care management of higher-quality chronic diseases. The Chronic Care Model gives a structure that redirects health care resources to better meet the demands and issues of individual with chronic illness.

Objectives: To explore the effectiveness of chronic care model for smokeless tobacco cessation in patients reporting to Sharad Pawar Dental College and Hospital.

Methodology: The study will be conducted among patients reporting to Out Patient Department of Sharad Pawar Dental College and Hospital who are chronic smokeless tobacco users. This study will be conducted between two groups, in one of the groups chronic Care Model will be used and behavioural counselling will be given and in other group only behavioural counselling will be given. Urinary cotinine level test will be performed on both groups of patients consuming smokeless tobacco.

Results: The chronic care model would be advantageous for the smokeless tobacco cessation. In India, there appears to be an immediate need for the promotion of awareness and informing people about the health problems associated with the use of smokeless tobacco through the model of chronic care.

Conclusion: The utilization of Chronic Care Model (CCM) helps patient realize that not only it is a habit to use smokeless tobacco, but a chronic condition that requires long-term treatment to cure it.
Effects of Anticoagulants and Corticosteroids Therapy in Patients Affected by Severe COVID-19 Pneumonia
Authors: Ghalilah Khalid , Sabir Abdul Momin , Alvi Irshad Ali , Alharbi Malak , Basabrain Abdulrahman , Aljundi Mahmooud , Almohammadi Ghazi , Almuairfi Zainab , Alharbi Raed , Ahmed A. A. E.
Published: September 2021

Background: In the absence of a standard of treatment for COVID-19, the combined use of anti-inflammatory (corticosteroids and Enoxaparin) and antiviral drugs may be more effective than using either modality alone in the treatment of COVID-19.

Methods: Patients hospitalized between April 10th, 2020, through May 10th, 2020, who had confirmed COVID-19 infection with clinical or radiographic evidence of pneumonia, in which 65 patients have moderate COVID-19 pneumonia, and 63 patients have severe COVID-19 pneumonia. All patients received early combination therapy of anti-inflammatory (corticosteroids and Enoxaparin) and antiviral drugs. They assessed for type and duration of treatment, and days need to wean from oxygen therapy, length of stay, virus clearance time, and complication or adverse events. All patients had more than 28 days follow up after discharge from the hospital.

Results: Moderate COVID-19 pneumonia group were 65 patients who received Enoxaparin, antiviral drugs, empirical antibiotics for pneumonia, and standard treatment for comorbidity. Male patients were 50 (76.9%) and female patients were 15 (23.1%). 34 (52.3%) patients have comorbidity, 25 (38.5%) patients have Diabetes Mellitus and 2 (3.1%) pregnant ladies. 19 (29.2%) patients were on low flow oxygen therapy, 3L oxygen or less to maintain oxygen saturation more than 92%. All patients discharged home with no major or minor bleeding complications or significant complications. Severe COVID-19 pneumonia group were 63 patients who received methylprednisolone, enoxaparin, antiviral drugs, empirical antibiotics for pneumonia, and standard treatment for comorbidity. Male patients were 55 (87.3%) and female patients were 8 (12.7%). 37 (58.7%) patients have comorbidity, and 24 (38.1%) patients have Diabetes Mellitus. 32 (50.8%) patients were on low flow oxygen therapy, 4-9L oxygen, and 31 (49.2%) patients were on low flow oxygen therapy, 10L oxygen or more, including 12 patients on a non-rebreathing mask. Patients received methylprednisolone were 37 (58.7%) for 3 days, 16 (25.4%) for 5 days and 10 (15.9%) for more than 5 days. Sixty-two patients discharged home with one patient had a long stay, and the other two transferred to ICU. One long-stay patient transferred to ICU on low flow oxygen therapy.

Conclusion: Early use of a combined anti-inflammatory (corticosteroids and Enoxaparin) and antiviral drugs treatment in patients with moderate to severe COVID-19 pneumonia prevent complications of the disease and improve clinical outcomes.
Herbal Medicines use in Pregnancy in Northern Cyprus
Authors: Tülek Eda , Yarici Filiz , Yavuz Dudu Özkum , Modu Mustapha Bulama , Meriçli Filiz
Published: September 2021

Objective: To identify the herbal medicinal products used in pregnancy in community pharmacies, the approach of pharmacists in Northern Cyprus and to compare the availability of the most commonly mentioned medicinal plants in accessible databases, in Northern Cyprus.

Design: Questionnaire was designed and administered to 263 community pharmacists in Northern Cyprus and gathered the data on herbal medicinal products they had and recommended to pregnant women. Databases such as ScienceDirect, PubMed, OpenAcces Journals were searched through the Near East University Grand Library’s Online Resources for keywords relating to the ‘herbal medicine’, ‘pregnancy’ ‘pregnant women’, ‘herbal products’. Descriptive statistics was used with IBM® Statistical product and service solutions software platform.

Location/Setting: Northern Cyprus

Outcome Measures: Herbal medicinal products used and recommended in pregnancy by community pharmacists in Northern Cyprus were identified. It has also been determined which of the most used plants in the world are grown in Northern Cyprus.

Results: The most recommended herbal pharmaceutical forms were herbal lozenges (n = 76, 31%), then herbal form of teas (n = 60, 24%), herbal oils (n = 57, 23%), herbal capsules (n = 36, 14%), other pharmaceutical forms (n=20, 8%). Within the limitation of our literature search, totally 650 medicinal plants (single or formula) used in pregnancy were determined.  Out of these 74 were mostly used worldwide, and it was discovered that 56 species out of these plants are grown or cultivated; 18 of the compiled species were imported species some of the genera have species growing naturally growing in Cyprus.

Conclusion: Pregnant women in Cyprus also follow their counterparts in other countries in developing interest in herbal medicines. The number of herbal medicines in the pharmacies owned by Turkish Cypriots is small. Interestingly, the result of this study showed that the pharmacists that were mainly Turkish Cypriots were found not to be selling herbal medicinal products to pregnant women without doctor’s prescriptions. This study recommends that the herbal medicines use in pregnancy should be the ones that have undergone in-depth evidence-based scientific researches with clinically proven efficacy that are known not only to the healthcare professionals such as medical doctors, midwives but also the pharmacists and the general public.
Physicochemical Characteristics, Anti-Lipase and Antioxidant Activities of Polysaccharide Extracted from Astragalus spinosis Grown in the Northern Region of Saudi Arabia
Authors: Khaled Hayet Ben , Nayeem Naira
Published: September 2021

Introduction: Northern border region of Saudi Arabia is one of the richest areas of traditional plants. This study was designed with an interest to work on the polysaccharide extracted from Astragalus spinosis leaves (PLAS) collected from rafha province.

Methods: Polysaccharide was isolated by hot water extraction, followed by ethanol precipitation. The isolated crude polysaccharide contains 62.43% ±2.09% carbohydrate and 0.29 ± 0.07% protein. The physicochemical characteristics, such as chemical composition, humidity, foaming capacity, solubility as well as water and oil holding capacity were evaluated. The structural feature of polysaccharide was studied through Fourier transform infrared (FT-IR) analysis and scanning electron microscopy.

Results: Polysaccharide extracted from Astragalus spinosis leaves showed good inhibitory lipase and antioxidant activities. It was observed that the total antioxidant capacity, the 1,1- diphenyl-2-picrylhydrazyl (DPPH) and the 2,2 -azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ATBS) radical scavenging activities were high at 2.0 mg/ml (97 µmol eq tocopherol ± 1.4, 73% ± 2.1 and 93% ± 0.9 respectively). 

Conclusion: the crude polysaccharide extract demonstrated good emulsion stabilizing capacities, with various hydrophobic compounds. It could be a potential source of natural antioxidants and emulsifiers.
Structural Characterization, Antimicrobial and Antioxidant Assay of Biogenically Synthesized Maghemite (γ-Fe2O3) Nanoparticles
Authors: Rose A. Leema , Shabushree B. , Thattil Preeja P.
Published: September 2021

Aims: The present study focused on the optical and morphological characterization, antioxidant and antimicrobial activities of the biogenically synthesized iron oxide nanoparticles. 

Methods: The preliminary phytochemical screening was done for the leaf extract of Annona reticulate L. The leaf extract and Ferrous Sulphate heptahydrate were used to synthesize the iron oxide nanoparticles under room temperature. The determination of antioxidant activity was done using DPPH free radical scavenging assay and the determination of antimicrobial activity using disc diffusion method.

Results: The UV-visible spectra showed the sharp absorption peak at 278 nm. The Fourier-transform infrared spectroscopy studies revealed the role of phytochemical constituents in the leaf extract for the iron oxide nanoparticles formation.  X-ray diffraction pattern showed the presence of γ phase of Fe2O3 nanoparticles. Scanning electron microscope analysis showed the moderately spherical morphology of γ-Fe2O3 nanoparticles and Energy-dispersive X-ray peaks showed the presence of iron and oxygen in the synthesized nanoparticles.  Particle size analysis showed that the synthesized γ-Fe2O3possessed an average size of 115.9 nm.

Conclusion: The synthesized γ-Fe2O3 nanoparticles have potential antioxidant and antimicrobial activity.
Common Presenting Complaints and Predisposing Factors among Adult Ophthalmic Patients with Low Vision and Blindness in Aba
Authors: Otuka O. A. I. , Ekeleme N. C. , Eweputanna L. I. , Iwuoha E. C. , Ubah J. N. , Kalu A.
Published: September 2021

Aim: To determine the common complaints and predisposing factors of low vision and blindness among adult ophthalmic patients in Abia State University Teaching Hospital, (ABSUTH), Aba, Nigeria.

Study Design: A retrospective, descriptive study.

Methodology: An institutional-based study involving 457 patients who attended Abia State University Teaching Hospital eye clinic between April and September 2018 was undertaken. The patients’ biodata, clinical history, ophthalmic examination findings, and results of ancillary investigations were obtained from patients’ hospital records within the period under study and analyzed using IBM SPSS version 25.0. AP-value of < 0.05 was taken to be statistical significant.

Result: A total of 457 patients comprising of 206 males and 251 females, aged 18-85 years were seen in the study period. Based on World Health Organization (WHO)’s definition of low vision and blindness, two hundred and eighty-four (62.1%) patients had normal vision, 25(5.5%) patients had low vision while 32(7%) patients were blind. The most common complaint was blurring of vision, 136 (23.5%) followed by itching of the eye, 91 (15.7%) and tearing, 86 (14.9%). Forty percent of the respondents’ complaints had lasted for over 12 months before presentation at the clinic. Common predisposing factors for low vision and blindness observed in this study were hypertension (24.1%), previous drug use (5%), previous use of traditional medication (1.3%) and family ocular history (3.7%). No statistically significant association was found between diagnostic data and family ocular history, previous use of traditional medication and previous drug use. Statistically, significant relationship was found between diagnostic data and blood pressure (P< 0.001).

Conclusion: There are various presentations of low vision and blindness in Aba. Routine eye check, early referral and appropriate treatment is advocated for the populace.
Chlorophyll Metabolism and Its Role in Responses and Adaptations to Stress
Authors: Mur Luis A. J. , Ougham Helen , Thomas Howard
Published: September 2021

This article discusses the role of chlorophyll metabolism in plant responses and adaptations to biotic and abiotic stresses. The metabolic pathways of chlorophyll (Chl) biosynthesis and catabolism are summarised. The precursor of tetrapyrrole synthesis is δ‐aminolaevulinic acid. Protoporphyrin IX is the branchpoint intermediate between the haem/bilin route and the direction leading to Chl. Disrupting individual steps in the biosynthetic pathway generally results in accumulation of phototoxic intermediates, damage by reactive oxygen species (ROS), light‐dependent cell death and tissue lesions. Mutations in the haem branch do not usually lead to lesion formation but can have a regulatory influence on Chl metabolism. The Chl
a/b
cycle links pigment synthesis and catabolism. The initial steps of Chl breakdown during senescence occur in the plastid and result in export of phyllobilins to the cytosol and vacuole. Disabling steps in the plastid pathway results in photosensitivity and runaway cell damage and death. Common plant responses to environmental stresses include chlorosis, cell death and premature senescence, and biotic and abiotic challenges frequently share aspects of underlying signal‐response networks. Resurrection plants and overwintering evergreens are discussed as case studies of the sensitivity of Chl metabolism to abiotic stresses. Responses to high light and temperature involve Chl catabolism, ROS, and pathways of chloroplast breakdown, including autophagy and vesiculation. In many instances, single‐gene and quantitative resistance to pathogens elicit a hypersensitive response (HR), involving a burst of ROS and localised cell death. Accumulated photodynamic intermediates of Chl metabolism are important sources of ROS in these contexts. Lines in which genes for Chl catabolism are overexpressed or disabled display enhanced or suppressed HR‐like symptoms respectively, and correspondingly resistant or susceptible reactions to biotic, and in some cases abiotic, challenges.
Deep clinicopathological phenotyping identifies a previously unrecognized pathogenic EMD splice variant
Authors: Calame Daniel G. , Fatih Jawid M. , Herman Isabella , Coban‐Akdemir Zeynep , Du Haowei , Mitani Tadahiro , Jhangiani Shalini N. , Marafi Dana , Gibbs Richard A. , Posey Jennifer E. , Mehta Vidya P. , Mohila Carrie A. , Abid Farida , Lotze Timothy E. , Pehlivan Davut , Adesina Adekunle M. , Lupski James R.
Published: September 2021

Exome sequencing (ES) has revolutionized rare disease management, yet only ~25%–30% of patients receive a molecular diagnosis. A limiting factor is the quality of available phenotypic data. Here, we describe how deep clinicopathological phenotyping yielded a molecular diagnosis for a 19‐year‐old proband with muscular dystrophy and negative clinical ES. Deep phenotypic analysis identified two critical data points: (1) the absence of emerin protein in muscle biopsy and (2) clinical features consistent with Emery‐Dreifuss muscular dystrophy. Sequencing data analysis uncovered an ultra‐rare, intronic variant in EMD, the gene encoding emerin. The variant, NM_000117.3: c.188‐6A > G, is predicted to impact splicing by in silico tools. This case thus illustrates how better integration of clinicopathologic data into ES analysis can enhance diagnostic yield with implications for clinical practice.
Robust CAWOF Kalman predictors for uncertain multi‐sensor generalized system
Authors: Tao Guili , Liu Wenqiang , Wang Xuemei , Zhang Jianfei , Yu Haiying
Published: September 2021

Robust centralized and weighted observation fusion (CAWOF) prediction algorithm is addressed in this article for an uncertain multi‐sensor generalized system with linear correlation between observation noises and an input white noise. This uncertainty in the generalized system primarily means that the variances of the aforementioned types of noise, as well as the multiplicative noise variances, are uncertain. Through singular value decomposition and virtual noise compensation, the original generalized system is changed to non‐generalized reduced‐order subsystems in which only noise variances are uncertain. Utilizing the minimax robustness estimation criterion, robust CAWOF Kalman predictors are put forward on account of the first subsystem with conservative upper bounds of noise variances. Eventually, robust observation fusion Kalman predictors of the original generalized system are proposed. The Lyapunov equation method is applied to verify two fusion predictors' robustness. With regard to all permissible uncertain practical noise variances, CAWOF predictors are robust, namely, the practical prediction error variances of two robust predictors will have minimum upper bounds. This equivalence between CAWOF Kalman predictors is proved by an information filter. In this article, the precision relationship of fusion predictors is given. Meanwhile, robust Kalman predictors for steady‐state case are proposed, and the astringency of robust time‐variant Kalman predictors is analyzed through the analysis of dynamic error system. The validity and correctness of proposed algorithm are proved by the simulation example of random dynamic input and output system in an economic system.
Highly Efficient Triplet‐Triplet‐Annihilation Upconversion Sensitized by a Thermally Activated Delayed Fluorescence Molecule in Optical Microcavities
Authors: Han Mengmeng , Zhu Zece , Ouyang Minting , Liu Yuan , Shu Xuewen
Published: September 2021

Triplet‐triplet‐annihilation (TTA) upconversion sensitized by a new thermally activated delayed fluorescence (TADF) molecule, BTZ‐DMAC‐4Br, is investigated in whispering gallery mode (WGM) microcavities made of toluene solutions filled into quartz capillaries. Since the utilization of the excitation light is improved in WGM microcavities through total internal reflection, the upconversion efficiency is enhanced greatly and an upconversion quantum yield of 24.6% is observed, which is a dozen times higher than that measured in conventional cuvettes. To the best of knowledge, this is the highest upconversion efficiency achieved in TADF sensitized TTA systems. Not only is a new material designed, but also the results provide a novel way to improve the TTA upconversion performance by utilizing the optical cavity effect, and the TTA microcavities may be used to construct highly efficient and low‐threshold photonic devices in many applications.
Ionic Dopant‐Induced Ordering Enhances the Thermoelectric Properties of a Polythiophene‐Based Block Copolymer
Authors: Dong Ban Xuan , Liu Ziwei , Onorato Jonathan W. , Ma Tengzhou , Strzalka Joseph , Bennington Peter , Luscombe Christine K. , Ober Christopher K. , Nealey Paul F. , Patel Shrayesh N.
Published: September 2021

Conjugated polymer‐based block copolymers (CP‐BCPs) are an unexplored class of materials for organic thermoelectrics. Herein, the authors report on the electronic conductivity (σ) and Seebeck coefficient (α) of a newly synthesized CP‐BCP, poly(3‐hexylthiophene)‐block‐poly (oligo‐oxyethylene methacrylate) (P3HT‐b‐POEM), upon solution co‐processing with lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), and subsequently vapor‐doping with a molecular dopant, 2,3,5,6‐tetrafluoro‐7,7,8,8‐tetracyanoquinodimethane (F4TCNQ). It is found that the addition of the hydrophilic block POEM greatly enhances the processability of P3HT, enabling homogeneous solution‐mixing with LiTFSI. Notably, interactions between P3HT‐b‐POEM with ionic species significantly improve molecular order and unexpectedly cause electrical oxidizing doping of P3HT block both in solution and solid‐states, a phenomenon that has not been previously observed in Li‐salt containing P3HT. Vapor doping of P3HT‐b‐POEM‐LiTFSI thin films with F4TCNQ further enhances σ and yields a thermoelectric power factor PF = α2σ of 13.0 µW m−1 K−2, which is more than 20 times higher than salt‐free P3HT‐b‐POEM sample. Through modeling thermoelectric behaviors of P3HT‐b‐POEM with the Kang‐Snyder transport model, the improvement in PF is attributed to higher electronic charge mobility originating from the enhanced molecular ordering of P3HT. The results demonstrate that solution co‐processing CP‐BCPs with a salt is a powerful method to control structure and performance of organic thermoelectric materials.
Nitrogen Vacancy Induced Coordinative Reconstruction of Single‐Atom Ni Catalyst for Efficient Electrochemical CO2 Reduction
Authors: Jia Chen , Li Shunning , Zhao Yong , Hocking Rosalie K. , Ren Wenhao , Chen Xianjue , Su Zhen , Yang Wanfeng , Wang Yuan , Zheng Shisheng , Pan Feng , Zhao Chuan
Published: September 2021

Transition metal nitrogen carbon based single‐atom catalysts (SACs) have exhibited superior activity and selectivity for CO2 electroreduction to CO. A favorable local nitrogen coordination environment is key to construct efficient metal‐N moieties. Here, a facile plasma‐assisted and nitrogen vacancy (NV) induced coordinative reconstruction strategy is reported for this purpose. Under continuous plasma striking, the preformed pentagon pyrrolic N‐defects around Ni sites can be transformed to a stable pyridinic N dominant Ni‐N2 coordination structure with promoted kinetics toward the CO2‐to‐CO conversion. Both the CO selectivity and productivity increase markedly after the reconstruction, reaching a high CO Faradaic efficiency of 96% at mild overpotential of 590 mV and a large CO current density of 33 mA cm‐2 at 890 mV. X‐ray adsorption spectroscopy and density functional theory (DFT) calculations reveal this defective local N environment decreases the restraint on central Ni atoms and provides enough space to facilitate the adsorption and activation of CO2 molecule, leading to a reduced energy barrier for CO2 reduction.
A Highly Tolerant Printing for Scalable and Flexible Perovskite Solar Cells
Authors: Xing Zhi , Lin Suyu , Meng Xiangchuan , Hu Ting , Li Dengxue , Fan Baojin , Cui Yongjie , Li Fengyu , Hu Xiaotian , Chen Yiwang
Published: September 2021

Homogeneity and stability of flexible perovskite solar cells (PSCs) are significant for the commercial feasibility in upscaling fabrication. Concretely, the mismatching between bottom interface and perovskite precursor ink can cause uncontrollable crystallization and undesired dangling bonds during the printing process. Herein, methylammonium acetate, serving as ink assistant (IAS) can effectively avoid the micron‐scale defects of perovskite film. The in situ optical microscope is applied to prove the IAS can inhibit the colloidal aggregation and induce more adequate crystallization growth, thus avoiding the micron‐scale defects of pinholes and intergranular cracking. Concurrently, 4‐chlorobenzenesulfonic acid is introduced into the electrode surface as a passivation layer to restore the deep traps at perovskite interface in nano‐scale. Finally, the target flexible devices (1.01 cm2) deliver a superior efficiency of 18.12% with improved air atmosphere stability. This multi‐scale defect repair strategy provides an integrated design concept of homogeneity and stability for scalable and flexible PSCs.
Bionanoscale Recognition Underlies Cell Fate and Therapy
Authors: Sun Shan , Deng Peng , Mu Li , Hu Xiangang , Guo Shuqing
Published: September 2021

Understanding the bionanoscale recognition of nanostructured architectures is critical to the design and application of nanomaterials, but the related information is not well understood. In this study, it is found that bionanoscale recognition underlies cell fate and therapy. For example, 1T phase (octahedral coordination) monolayer MoS2 exhibits a markedly stronger affinity for fibronectin than the 2H structure (triangular prism coordination) and promotes cell spreading and differentiation. The van der Waals energy and increased turn components contribute to the high adhesion of fibronectin onto the 1T‐MoS2 structure. 1T‐MoS2 exhibits a significantly stronger affinity (KD, 6.59 × 10−7 m) for liposomes than 2H‐MoS2 (1.21 × 10−6 m) due to strong hydrophobic interactions. The existence of octahedrally coordinated atomic structures that improve cell viability by enhancing the neurite length is first proven by random forest and structural equation models. Consequently, octahedral coordination disaggregates α‐synuclein (e.g., by decreasing β‐sheets and increasing coil structures) and protects cells and hosts against Parkinson's disease. As a proof‐of‐principle demonstration, these findings indicate that bionanoscale recognition underlies the design of biomaterials and cell therapeutics.
Biomimetic Ultraflexible Piezoresistive Flow Sensor Based on Graphene Nanosheets and PVA Hydrogel
Authors: Abolpour Moshizi Sajad , Moradi Hamed , Wu Shuying , Han Zhao Jun , Razmjou Amir , Asadnia Mohsen
Published: September 2021

Flow sensors play a critical role in monitoring flow parameters, including rate, velocity, direction, and rotation frequency. In this paper, inspired by biological hair cells in the human vestibular system, an innovative flow sensor is developed based on polyvinyl alcohol (PVA) hydrogel nanocomposites with a maze‐like network of vertically grown graphene nanosheets (VGNs). The VGNs/PVA hydrogel absorbs a copious amount of water when immersed in water, making the sensor highly sensitive to tiny stimuli underwater. The sensor demonstrates a high sensitivity (5.755 mV (mm s−1)−1) and extremely low velocity detection (0.022 mm s−1). It also reveals outstanding performance in detecting low‐frequency oscillatory flows down to 0.1 Hz, which make it suitable for many biomedical applications. As one of the potential applications of the sensor, it exhibits excellent performance in mimicking various physiological conditions of vestibular hair cells. To explain the experimental results, a complete finite element simulation is developed to model the piezoresistive effect of VGNs/PVA thin film structure. This is the first attempt to develop hydrogel–graphene nanosheet‐based flow sensors, which creates the closest artificial sensor to vestibular hair cells. This miniaturized hair cell sensor paves the way for utilizing hydrogels to develop next‐generation of ultrasensitive flow sensors for biomedical applications.
Mechanochemical Transformation of CF3 Group: Synthesis of Amides and Schiff Bases
Authors: Mkrtchyan Satenik , Jakubczyk Michał , Lanka Suneel , Yar Muhammad , Ayub Khurshid , Shkoor Mohanad , Pittelkow Michael , Iaroshenko Viktor O.
Published: September 2021

We communicate two mild, solvent‐free mechanochemical coupling transformations of CF3 group with nitro compounds into amides or Schiff bases employing Ytterbia as a catalyst. This process proceeds via C−F bond activation, accompanied with utilisation of Si‐based reductants/oxygen scavengers – reductants of the nitro group. The scope and limitations of the disclosed methodologies are thoroughly studied. To the best of our knowledge, this work is the first example of mechanical energy promoted transformation of the inert CF3 group into other functionalities.

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Recent Advances in Transformations Involving Electron‐Rich Alkenes: Functionalization, Cyclization, and Cross‐Metathesis Reactions
Authors: Zhou Fei , Li Meng , Jiang Huanfeng , Wu Wanqing
Published: September 2021

Due to the versatile reactivity and molecular complexity, as well as diversity, electron‐rich alkenes bearing nitrogen, oxygen, or sulfur atoms have been regarded as versatile reagents in organic synthesis. This review mainly focuses on the recent advances in the reaction development of electron‐rich alkenes since 2000, including mono‐/difunctionalization reactions, cyclization reactions, and cross‐metathesis reactions. Numerous protocols enabling facile and efficient transformations of electron‐rich alkenes to valuable compounds have been developed, which are discussed with special emphasis placed on the mechanistic aspects and the synthetic utilities. We hope that this review will help inspire future studies and promote developments in this area.

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Conservation agriculture can help the South American Andean region achieve food security
Authors: Barrera Víctor H. , Delgado Jorge A. , Alwang Jeffrey R.
Published: September 2021

The Andean region of Ecuador is dominated by small‐scale agriculture on steep slopes vulnerable to erosion, soil degradation, and subsequent productivity loss. Soil erosion rates exceed the average rate of soil formation by 9–286 times, making current agricultural practices in the region unsustainable, and threatening to increase food insecurity. The projected effects of a changing climate vary across the Andean region, with higher precipitation and erosion rates projected for some areas. However, even in areas where the precipitation rates are expected to be lower, the projected erosion rates will still be unsustainable. Research on conservation agriculture (CA) practices conducted from 2008 to 2017 in the highlands of Ecuador suggests that yields and cost savings ultimately make several CA production systems profitable compared to conventional practices. In the very short term, large gains did not emerge, and the best that could be said about CA is that it did not reduce productivity. Over the medium term, improvements in soil health (lower erosion) led to higher profitability that made the practices more profitable than conventional practices over the entire rotation. However, adoption of these alternatives by local producers, even in research areas, is low. Lack of public or private agricultural extension contributes to slow diffusion of new technology and best management practices in the region. There is a need to develop improved communication with local farmers to more effectively relay how CA protects the soil, mitigates degradation, and provides a means to achieve food security and avoid a humanitarian crisis.
Health and safety risk perceptions and needs of app‐based drivers during COVID‐19
Authors: Beckman Kerry L. , Monsey Lily M. , Archer Megan M. , Errett Nicole A. , Bostrom Ann , Baker Marissa G.
Published: September 2021

Background

App‐based drivers face work disruptions and infection risk during a pandemic due to the nature of their work, interactions with the public, and lack of workplace protections. Limited occupational health research has focused on their experiences.

Methods

We surveyed 100 app‐based drivers in Seattle, WA to assess risk perceptions, supports, and controls received from the company that employs them, sources of trust, stress, job satisfaction, COVID‐19 infection status, and how the pandemic had changed their work hours. Data were summarized descriptively and with simple regression models. We complemented this with qualitative interviews to better understand controls and policies enacted during COVID‐19, and barriers and facilitators to their implementation.

Results

Drivers expressed very high levels of concern for exposure and infection (86%–97% were “very concerned” for all scenarios). Only 31% of drivers reported receiving an appropriate mask from the company for which they drive. Stress (assessed via PSS‐4) was significantly higher in drivers who reported having had COVID‐19, and also significantly higher in respondents with lower reported job satisfaction. Informants frequently identified supports such as unemployment benefits and peer outreach among the driver community as ways to ensure that drivers could access available benefits during COVID‐19.

Conclusions

App‐based drivers received few protections from the company that employed them, and had high fear of exposure and infection at work. There is increased need for health‐supportive policies and protections for app‐based drivers. The most effective occupational and public health regulations would cover employees who may not have a traditional employer–employee relationship.