bluuebunny/crossref_metadata_2025 huggingface dataset:
Increase of Yield, Lycopene, and Lutein Content in Tomatoes Grown Under Continuous PAR Spectrum LED Lighting
Authors: Dannehl Dennis , Schwend Thomas , Veit Daniel , Schmidt Uwe
Published: February 2021

Light emitting diodes (LEDs) are an energy efficient alternative to high-pressure sodium (HPS) lighting in tomato cultivation. In the past years, we have learned a lot about the effect of red and blue LEDs on plant growth and yield of tomatoes. From previous studies, we know that plants absorb and utilize most of the visible spectrum for photosynthesis. This part of the spectrum is referred to as the photosynthetically active radiation (PAR). We designed a LED fixture with an emission spectrum that partially matches the range of 400 to 700 nm and thus partially covers the absorption spectrum of photosynthetic pigments in tomato leaves. Tomato plants grown under this fixture were significantly taller and produced a higher fruit yield (14%) than plants grown under HPS lighting. There was no difference in the number of leaves and trusses, leaf area, stem diameter, the electron transport rate, and the normalized difference vegetation index. Lycopene and lutein contents in tomatoes were 18% and 142% higher when they were exposed to the LED fixture. However, the ß-carotene content was not different between the light treatments. Transpiration rate under LED was significantly lower (40%), while the light use efficiency (LUE) was significantly higher (19%) compared to HPS lighting. These data show that an LED fixture with an emission spectrum covering the entire PAR range can improve LUE, yields, and content of secondary metabolites in tomatoes compared to HPS lighting.
A Genome-Wide Genetic Diversity Scan Reveals Multiple Signatures of Selection in a European Soybean Collection Compared to Chinese Collections of Wild and Cultivated Soybean Accessions
Authors: Saleem Aamir , Muylle Hilde , Aper Jonas , Ruttink Tom , Wang Jiao , Yu Deyue , Roldán-Ruiz Isabel
Published: February 2021

Targeted and untargeted selections including domestication and breeding efforts can reduce genetic diversity in breeding germplasm and create selective sweeps in crop genomes. The genomic regions at which selective sweeps are detected can reveal important information about signatures of selection. We have analyzed the genetic diversity within a soybean germplasm collection relevant for breeding in Europe (the EUCLEG collection), and have identified selective sweeps through a genome-wide scan comparing that collection to Chinese soybean collections. This work involved genotyping of 480 EUCLEG soybean accessions, including 210 improved varieties, 216 breeding lines and 54 landraces using the 355K SoySNP microarray. SNP calling of 477 EUCLEG accessions together with 328 Chinese soybean accessions identified 224,993 high-quality SNP markers. Population structure analysis revealed a clear differentiation between the EUCLEG collection and the Chinese materials. Further, the EUCLEG collection was sub-structured into five subgroups that were differentiated by geographical origin. No clear association between subgroups and maturity group was detected. The genetic diversity was lower in the EUCLEG collection compared to the Chinese collections. Selective sweep analysis revealed 23 selective sweep regions distributed over 12 chromosomes. Co-localization of these selective sweep regions with previously reported QTLs and genes revealed that various signatures of selection in the EUCLEG collection may be related to domestication and improvement traits including seed protein and oil content, phenology, nitrogen fixation, yield components, diseases resistance and quality. No signatures of selection related to stem determinacy were detected. In addition, absence of signatures of selection for a substantial number of QTLs related to yield, protein content, oil content and phenological traits suggests the presence of substantial genetic diversity in the EUCLEG collection. Taken together, the results obtained demonstrate that the available genetic diversity in the EUCLEG collection can be further exploited for research and breeding purposes. However, incorporation of exotic material can be considered to broaden its genetic base.
Drop-the-p: Bayesian CFA of the Multidimensional Scale of Perceived Social Support in Australia
Authors: Santiago Pedro Henrique Ribeiro , Quintero Adrian , Haag Dandara , Roberts Rachel , Smithers Lisa , Jamieson Lisa
Published: February 2021

Aim

We aimed to investigate whether the 12-item Multidimensional Scale of Perceived Social Support (MSPSS) constitutes a valid and reliable measure of social support for the general adult Australian population.

Methods

Data were from Australia’s National Survey of Adult Oral Health 2004–2006 and included 3899 participants aged 18 years old and over. The psychometric properties were evaluated with Bayesian confirmatory factor analysis. One-, two-, and three-factor (Significant Other, Family and Friends) structures were tested. Model fit was assessed with the posterior predictivep-value (PPPχ2), Bayesian root mean square error of approximation (BRMSEA), and Bayesian comparative fit index (BCFI). Dimensionality was tested by comparing competing factorial structures with the Bayes factor (BF). Reliability was evaluated with the Bayesian ΩH. Convergent validity was investigated with the Perceived Stress Scale (PSS) and discriminant validity with the Perceived Dental Control scale (PDC-3).

Results

The theoretical three-factor model (Significant Other, Family, and Friends) provided a good fit to the data [PPPχ2< 0.001, BRMSEA = 0.089-95% credible interval (CrI) (0.088, 0.089); BCFI = 0.963-95% CrI (0.963, 0.964)]. The BF provided decisive support for the three-factor structure in relation to the other structures. The SO [BΩH= 0.95 - 95% CrI (0.90, 0.99)], FA (BΩH= 0.92 - 95% CrI (0.87, 0.97), and FR (BΩH= 0.92 - 95% CrI (0.88, 0.97)] subscales displayed excellent reliability. The MSPSS displayed initial evidence of convergent and discriminant validity.

Conclusion

The MSPSS demonstrated good psychometric properties and excellent reliability in a large Australian sample. This instrument can be applied in national surveys and provide evidence of the role of social support in the Australian population.
Why Do People Support Online Crowdfunding Charities? A Case Study From China
Authors: Jiao Huifang , Qian Lamei , Liu Tianzhuo , Ma Lijun
Published: February 2021

Whereas the effect of people’s motivations to give to traditional, off-line charities has been extensively investigated, their motivations to support online charitable crowdfunding projects are largely unexplored. The present study examines the influences of extrinsic motivations (such as reputation, the wish to signal a certain image; and reciprocity, the expectation on future return for their present contribution), intrinsic motivations (such as a sense of belonging, the feeling of belonging to an integral part of a positive community; joy of giving, the anticipated positive emotions experienced by helping others; altruism, intrinsic desire to help others without expectation of a return; and financial constraints, individuals’ personally felt financial stresses induced by donations), and social interactions (such as social influence, people’s perception of how their close acquaintances believe they should support the project; and social ties, the strength of the relationship between the individual and the project initiator) on intentions to support charitable crowdfunding behaviors, namely, the willingness to share (WTS) project information and the intention to donate (ITD) money. Hierarchical multiple regression analyses on self-reported survey data from 617 respondents in China reveal support for the hypotheses. The results show that intrinsic motivations and social ties are predictors for both supporting behaviors. Reputation and social influence motivate people to share projects, but have no significant effects on their ITD. Reciprocity is positively, and financial constraints are negatively, related to ITD but have no significant effects on WTS. These findings offer insights into the motivations driving individuals’ participation in charitable crowdfunding. The implications for both platforms and fundraisers are discussed.
Mental Health Consequences of Lockdown During the COVID-19 Pandemic: A Cross-Sectional Study
Authors: Msherghi Ahmed , Alsuyihili Ali , Alsoufi Ahmed , Ashini Aimen , Alkshik Zenib , Alshareea Entisar , Idheiraj Hanadi , Nagib Taha , Abusriwel Munera , Mustafa Nada , Mohammed Fatima , Eshbeel Ayah , Elbarouni Abobaker , Elhadi Muhammed
Published: February 2021

Objective

We aimed to provide an overview of the psychological status and behavioral consequences of the lockdown during the COVID-19 pandemic in Libya.

Methods

A cross-sectional study was conducted among the Libyan population through May and June 2020 in more than 20 cities. The survey comprised basic demographic data of the participants and anxiety symptoms measured using the seven-item Generalized Anxiety Disorder scale (GAD-7) with ≥15 as the cut-off score for clinically significant anxiety symptoms. Additionally, a survey regarding the lockdown effect was administered, which consisted of several parts, to measure the lockdown status.

Results

A total of 8084 responses were recorded, of which, 5090 (63%) were women and 2994 (37%) were men. The mean age (SD) for study participants was 27.2 (8.9) years. Among the participants, 1145 (14.2%) reached the cut-off score to detect anxiety symptoms; however, of the study variables, only five were predictors of clinically significant anxiety: age, gender, marital status, work status, being a financial supporter for the family, and being infected with COVID-19. Women had 1.19 times higher odds to exhibit anxiety symptoms than men. Increasing age was significantly associated with reduced likelihood of exhibiting anxiety symptoms, whereas being married was significantly associated with higher likelihood of anxiety symptoms, compared to not being married. Being suspended from work was associated with an increase in the likelihood of anxiety symptoms. However, we found that being infected with COVID-19 was associated with a 9.59 times higher risk of exhibiting severe anxiety symptoms. Among the study participants, 1451 (17.9%) reported a physical and/or verbal abuse episode from family members, 958 (11.9%) reported abuse outside the family, and 641 (7.9%) reported abuse from enforcers, during the lockdown.

Conclusion

Our study provided an overview of the psychological and behavioral status, among those who resided in Libya during the civil war and COVID-19 pandemic. The study demonstrates a concerningly high level of clinically significant anxiety during lockdown among the Libyan population during Libya’s lockdown period.
The Association Between Maladaptive Metacognitive Beliefs and Emotional Distress in People Living With Amyotrophic Lateral Sclerosis
Authors: Dodd Rachel , Fisher Peter L. , Makin Selina , Moore Perry , Cherry Mary Gemma
Published: February 2021

Objective

Approximately half of all people living with amyotrophic lateral sclerosis (ALS) experience persistent or recurrent emotional distress, yet little is known about the psychological processes that maintain emotional distress in this population. The self-regulatory executive functioning (S-REF) model specifies that maladaptive metacognitive beliefs and processes are central to the development and maintenance of emotional distress. This study explored whether maladaptive metacognitive beliefs are associated with emotional distress after controlling for demographic factors, time since diagnosis, and current level of physical functioning.

Design

In a cross-sectional design, 75 adults with a diagnosis of ALS completed self-report questionnaires. Participants had a mean age of 60.40 years, mean duration of symptoms 63.92 months, and male:female gender ratio of 14:11.

Main Outcome Measures

Questionnaires assessed emotional distress (HADS, adapted for ALS), physical functioning (ALSFRS-R), repetitive negative thinking (RTQ-10), metacognitive beliefs (MCQ-30), and demographic factors.

Results

Maladaptive metacognitive beliefs explained additional variance in emotional distress after controlling for age, gender, time since diagnosis, physical functioning, and repetitive negative thinking. Repetitive negative thinking partially mediated the relationships between positive and negative metacognitive beliefs and emotional distress.

Conclusions

These data support the utility of the metacognitive model in understanding emotional distress in people with ALS. Examination of the temporal relationship between maladaptive metacognitive beliefs and emotional distress in people living with ALS may help to guide the development of therapeutic approaches.
Contributions of Individual, Family, and School Characteristics to Chilean Students’ Social Well-Being at School
Authors: López Verónica , Torres-Vallejos Javier , Ascorra Paula , González Luis , Ortiz Sebastián , Bilbao Marian
Published: February 2021

Schools are an essential part of students’ lives and can promote and facilitate their well-being. Although research on well-being among school-aged children and adolescents has distinguished subjective well-being from social well-being, very few studies examined student’s social well-being at school (SWS). SWS is understood as students’ valuation of the circumstances and functioning of their school. This framework posits that the context of the schools can shape students’ perception of feeling integrated and making significant contributions to their schools. However, not much is known regarding the joint contribution of individual, family, and school characteristics to students’ SWS. This study analyzed these joint contributions in a nationally representative sample of 6,389 children and adolescents enrolled in 5th–11th grades. Findings show that being female and younger were individual predictors of SWS. Students’ satisfaction with their family and fewer changes of schools were also significant contributors. When students’ perceptions of their schools were incorporated, the individual and family characteristics decreased or lost significance. In the full model, the highest contribution to SWS was explained by the school-level aggregated perception of school climate. These findings call for integrated policies and practices to foster students’ sense of belonging, feeling integrated, and contribution to their schools, with a focus on school-level interventions to improve SWS through positive and engaging school climates that foster students’ sense of agency.
Case Report: Feasibility of a Novel Virtual Reality-Based Intervention for Patients With Schizophrenia
Authors: Vass Edit , Simon Viktória , Fekete Zita , Kis Balázs , Simon Lajos
Published: February 2021

Schizophrenia is a severe and disabling mental illness, associated with persistent difficulties in social functioning. While gaining and retaining a job or staying socially integrated can be very difficult for the patients, the treatment of poor functionality remains challenging with limited options in pharmacotherapy. To address the limitations of medical treatment, several interesting and innovative approaches have been introduced in the field of psychotherapy. Recent approaches incorporate modern technology as well, such as virtual reality. A potential therapeutic benefit of virtual reality is particularly significant when an interpersonal dimension of the problem needs to be addressed. One example is a Virtual Reality based Theory of Mind Intervention (VR-ToMIS), a novel method, which enables patients to practice complex social interactions without the burden of real-life consequences. Our paper presents a case report showing promising results of VR-ToMIS. Ms. Smith is a 50- year-old patient who has been suffering from schizophrenia for 20 years. Although in her case there was no problem with compliance throughout the years, she had severe problems regarding social functionality. With VR-ToMIS, she improved in ToM and communicative-pragmatic skills. The effects of the intervention went beyond the increased scores of the tests. Before the intervention there was a risk of the patient becoming unemployed as she was unable to follow the main principles of communicative exchange. Usually, her contribution was more informative than was required. After the intervention her communication became more balanced and she could retain her job. This case suggests that VR-ToMIS may be a promising tool for treating social disfunction in schizophrenia.
COVID-19 and Personality: A Cross-Sectional Multicenter Study of the Relationship Between Personality Factors and COVID-19-Related Impacts, Concerns, and Behaviors
Authors: AL-Omiri Mahmoud K. , Alzoubi Ibrahim A. , Al Nazeh Abdullah A. , Alomiri Abdallah K. , Maswady Mohannad N. , Lynch Edward
Published: February 2021

Background: This cross-sectional observational study aimed to evaluate coronavirus disease 2019 (COVID-19)-related precautions to avoid COVID-19 infection, distress and behavioral changes, fears and concerns, and effects on opinions and beliefs among participants from different backgrounds and also to identify the relationships between personality factors and COVID-19-related changes and impacts.

Methods: One thousand and three hundred nineteen participants (744 females and 575 males, mean age ± SD = 32.7 ± 11.6 years) completed a three-section survey collecting data regarding demographic information, personality factors [using the NEO Five-Factor Inventory (NEO-FFI)], and COVID-19-related issues (using the VAS scale).

Findings: COVID-19 was associated with changes related to precautions to avoid COVID-19 infection, distress and behavioral changes, fears and concerns, and effects on opinions and beliefs (P < 0.05). Higher neuroticism scores were associated with more negative COVID-19-related changes and impacts (P < 0.05). Higher extraversion, agreeableness, and conscientiousness scores were associated with more acceptance of COVID-19 containment measures as well as less COVID-19-related changes and impacts (P < 0.05).

Conclusions: Personality factors were associated with COVID-19-related impacts. These findings demonstrate the importance of the relationship between personality factors and COVID-19-related changes.
Interpersonal Change During Inpatient CBASP Treatment: Focus on Group Therapy
Authors: Guhn Anne , Schön David , Zische Yvonne , Sterzer Philipp , Köhler Stephan
Published: February 2021

Background: The Cognitive Behavioral Analysis System of Psychotherapy (CBASP) has been tailored specifically to the demands of patients with persistent depressive disorder (PDD). According to the CBASP model, PDD patients are supposed to live perceptually disconnected from their social environment, which consequently maintains depression. While initially developed as an individual treatment modality, the adaptation for group therapy yields an important interpersonal space. However, little is known about the specific factors that contribute to patients' benefit from the CBASP group modality.

Methods: The analyzed sample comprised N = 87 PDD patients who completed a 12 week multimodal inpatient treatment including 2 weekly CBASP-specific individual and group sessions, respectively, as well as CBASP-unspecific medical contacts, pharmacotherapy and complementary therapies. Group sessions included trainings in situational analysis and interpersonal skills. Interpersonal change over therapy was examined based on the patients' self-perceived interpersonal problems (IIP) and the impact messages as perceived by their individual therapists (IMI). Pre and post-treatment data were compared using within-sample t-tests. Additionally, patients evaluated CBASP group therapy on a feedback form. They were invited to reflect on individual benefits and its helpful and unhelpful aspects. Qualitative content analysis with inductive category development was used to analyze feedback. Inter-rater reliability was computed to confirm categories before summarizing the frequencies of reported factors.

Results: Self-perceived interpersonal distress significantly decreased over therapy. Patients reported reduced interpersonal problems and therapists reported more friendly and dominant impact messages. Interestingly, patients who showed a significant depressive symptom reduction described higher change scores. Regarding qualitative data, patients reported five main benefits from group therapy: Gain in social competence, self-confidence, self-reflection, interpersonal dynamics, and optimism/universality. Patients responding to CBASP identified significantly more factors than non-responders.

Conclusions: Compared to studies with individual CBASP only, the present findings suggest that CBASP group therapy may contribute to the improvement of interpersonal behavior. Group therapy is discussed as a potential boosting effect for individual CBASP. However, as the present data were collected in a multimodal inpatient setting without competitor, randomized controlled trials are warranted that investigate the specific benefits of the group modality or the combined individual and group therapy over individual CBASP only.
Electroencephalographic Microstates in Schizophrenia and Bipolar Disorder
Authors: Wang Fanglan , Hujjaree Khamlesh , Wang Xiaoping
Published: February 2021

Schizophrenia (SCH) and bipolar disorder (BD) are characterized by many types of symptoms, damaged cognitive function, and abnormal brain connections. The microstates are considered to be the cornerstones of the mental states shown in EEG data. In our study, we investigated the use of microstates as biomarkers to distinguish patients with bipolar disorder from those with schizophrenia by analyzing EEG data measured in an eyes-closed resting state. The purpose of this article is to provide an electron directional physiological explanation for the observed brain dysfunction of schizophrenia and bipolar disorder patients.

Methods: We used microstate resting EEG data to explore group differences in the duration, coverage, occurrence, and transition probability of 4 microstate maps among 20 SCH patients, 26 BD patients, and 35 healthy controls (HCs).

Results: Microstate analysis revealed 4 microstates (A–D) in global clustering across SCH patients, BD patients, and HCs. The samples were chosen to be matched. We found the greater presence of microstate B in BD patients, and the less presence of microstate class A and B, the greater presence of microstate class C, and less presence of D in SCH patients. Besides, a greater frequent switching between microstates A and B and between microstates B and A in BD patients than in SCH patients and HCs and less frequent switching between microstates C and D and between microstates D and C in BD patients compared with SCH patients.

Conclusion: We found abnormal features of microstate A, B in BD patients and abnormal features of microstate A, B, C, and D in SCH patients. These features may indicate the potential abnormalities of SCH patients and BD patients in distributing neural resources and influencing opportune transitions between different states of activity.
Health Care Professionals' Confidence and Preferences for Diagnostic Assays for SARS-CoV-2: A Global Study
Authors: Shields Adrian M. , Brown Hannah , Phillips Neil , Drayson Mark T. , Richter Anton A. , Richter Alex G.
Published: February 2021

Background: The COVID-19 pandemic has led to an urgent requirement for novel diagnostic tests that determine infection with SARS-CoV-2 and the development of an immune response against it. The perspective of end users on the characteristics and clinical use of these assays has not been previously considered.

Methods: We surveyed 17,186 health care professions (HCPs) in 29 countries to gauge opinion on the design, use, diagnostic impact and diagnostic accuracy of COVID-19 tests. Results were correlated with national statistics on the burden of disease and testing in individual countries.

Results: HCPs overwhelmingly recognized the importance of COVID-19 tests but 37.1% were unsure of the appropriate timing of investigations relative to disease symptoms. Confidence in the diagnostic accuracy of assays varied inversely with COVID-19-related mortality in individual countries but had no relationship with the total number of tests performed. There was global consensus that the most important impact of positive antigen and antibody testing was confidence in returning to work following recovery. Saliva was the preferred sampling fluid for COVID-19 diagnostic tests in all groups surveyed.

Conclusions: HCP input can ensure novel assays are fit for purpose in varied global health care settings, but HCPs may require support to effectively use novel diagnostics thus minimizing waste when supplies are limited.
Curse or Blessing? Obesity and Income-Related Inequality in the Chinese Labor Force
Authors: Tang Chengxiang , Yang Xiaocong , Peng Fei , Hu Xianglian
Published: February 2021

China owns a huge labor force of around half billion workers in 2018. However, little is known about the prevalence of obesity and the association between obesity and economic status in this special population. By employing the concentration index (CI) and decomposition analysis, this paper addresses this knowledge gap by using the most recent nationally representative dataset. In specific, this study examines the prevalence of obesity and the socioeconomic gradient in the probability of obesity among Chinese workers between 16 and 65. Our results show that the prevalence of obesity is completely different by using a different measure: the overall prevalence of being general obesity (measured by body mass index, BMI ≥ 28) varies by gender and residency from a minimum of 5.88% to a maximum of 9.46%, whereas abdominal obesity (measured by waist circumference, WCmale ≥ 85 cm & WCfemale ≥ 80 cm) prevalence presents a socking level from 64.53% to 67.69%. Moreover, the results show a pro-rich distribution of obesity (general and abdominal) among male workers (CIBMI = 0.112; CIWC = 0.057) and a pro-poor distribution among female workers (CIBMI = −0.141; CIWC = −0.166). We also find that the direction of the contribution of socioeconomic factors to income-related inequalities in obesity differs by gender. These results have substantial implications for the measurement of socioeconomic inequality in adiposity and for improving health-related policies targeting the Chinese labor force.
Lessons Learned From Immersive and Desktop VR Training of Mines Rescuers
Authors: Pedram Shiva , Skarbez Richard , Palmisano Stephen , Farrelly Matthew , Perez Pascal
Published: February 2021

This paper discusses results from two successive rounds of virtual mines rescue training. The first round was conducted in a surround projection environment (360-VR), and the second round was conducted in desktop virtual reality (Desktop-VR). In the 360-VR condition, trainees participated as groups, making collective decisions. In the Desktop-VR condition, trainees could control their avatars individually. Overall, 372 participants took part in this study, including 284 mines rescuers who took part in 360-VR, and 243 in Desktop-VR. (155 rescuers experienced both.) Each rescuer who trained in 360-VR completed a battery of pre- and post-training questionnaires. Those who attended the Desktop-VR session only completed the post-training questionnaire. We performed principal components analysis on the questionnaire data, followed by a multiple regression analysis, the results of which suggest that the chief factor contributing to positive learning outcome was Learning Context, which extracted information about the quality of the learning content, the trainers, and their feedback. Subjective feedback from the Desktop-VR participants indicated that they preferred Desktop-VR to 360-VR for this training activity, which highlights the importance of choosing an appropriate platform for training applications, and links back to the importance of Learning Context. Overall, we conclude the following: 1) it is possible to train effectively using a variety of technologies but technology that is well-suited to the training task is more useful than technology that is “more advanced,” and 2) factors that have always been important in training, such as the quality of human trainers, remain critical for virtual reality training.
Effects of Latitude-Dependent Gravity Wave Source Variations on the Middle and Upper Atmosphere
Authors: Yiğit Erdal , Medvedev Alexander S. , Ern Manfred
Published: February 2021

Atmospheric gravity waves (GWs) are generated in the lower atmosphere by various weather phenomena. They propagate upward, carry energy and momentum to higher altitudes, and appreciably influence the general circulation upon depositing them in the middle and upper atmosphere. We use a three-dimensional first-principle general circulation model (GCM) with implemented nonlinear whole atmosphere GW parameterization to study the global climatology of wave activity and produced effects at altitudes up to the upper thermosphere. The numerical experiments were guided by the GW momentum fluxes and temperature variances as measured in 2010 by the SABER (Sounding of the Atmosphere using Broadband Emission Radiometry) instrument onboard NASA’s TIMED (Thermosphere Ionosphere Mesosphere Energetics Dynamics) satellite. This includes the latitudinal dependence and magnitude of GW activity in the lower stratosphere for the boreal summer season. The modeling results were compared to the SABER temperature and total absolute momentum flux and Upper Atmosphere Research Satellite (UARS) data in the mesosphere and lower thermosphere. Simulations suggest that, in order to reproduce the observed circulation and wave activity in the middle atmosphere, GW fluxes that are smaller than observed fluxes have to be used at the source level in the lower atmosphere. This is because observations contain a broader spectrum of GWs, while parameterizations capture only a portion relevant to the middle and upper atmosphere dynamics. Accounting for the latitudinal variations of the source appreciably improves simulations.
Analysis of the Global Population Structure of Paenibacillus larvae and Outbreak Investigation of American Foulbrood Using a Stable wgMLST Scheme
Authors: Papić Bojan , Diricks Margo , Kušar Darja
Published: February 2021

Paenibacillus larvae causes the American foulbrood (AFB), a highly contagious and devastating disease of honeybees. Whole-genome sequencing (WGS) has been increasingly used in bacterial pathogen typing, but rarely applied to study the epidemiology of P. larvae. To this end, we used 125 P. larvae genomes representative of a species-wide diversity to construct a stable whole-genome multilocus sequence typing (wgMLST) scheme consisting of 5745 loci. A total of 51 P. larvae isolates originating from AFB outbreaks in Slovenia were used to assess the epidemiological applicability of the developed wgMLST scheme. In addition, wgMLST was compared with the core-genome MLST (cgMLST) and whole-genome single nucleotide polymorphism (wgSNP) analyses. All three approaches successfully identified clusters of outbreak-associated strains, which were clearly separated from the epidemiologically unlinked isolates. High levels of backward comparability of WGS-based analyses with conventional typing methods (ERIC-PCR and MLST) were revealed; however, both conventional methods lacked sufficient discriminatory power to separate the outbreak clusters. The developed wgMLST scheme provides an improved understanding of the intra- and inter-outbreak genetic diversity of P. larvae and represents an important progress in unraveling the genomic epidemiology of this important honeybee pathogen.
Genomic Insights of Multidrug-Resistant Escherichia coli From Wastewater Sources and Their Association With Clinical Pathogens in South Africa
Authors: Mbanga Joshua , Amoako Daniel G. , Abia Akebe L. K. , Allam Mushal , Ismail Arshad , Essack Sabiha Y.
Published: February 2021

There is limited information on the comparative genomic diversity of antibiotic-resistant Escherichia coli from wastewater. We sought to characterize environmental E. coli isolates belonging to various pathotypes obtained from a wastewater treatment plant (WWTP) and its receiving waters using whole-genome sequencing (WGS) and an array of bioinformatics tools to elucidate the resistomes, virulomes, mobilomes, clonality, and phylogenies. Twelve multidrug-resistant (MDR) diarrheagenic E. coli isolates were obtained from the final effluent of a WWTP, and the receiving river upstream and downstream of the WWTP were sequenced on an Illumina MiSeq machine. The multilocus sequence typing (MLST) analysis revealed that multiple sequence types (STs), the most common of which was ST69 (n = 4) and ST10 (n = 2), followed by singletons belonging to ST372, ST101, ST569, ST218, and ST200. One isolate was assigned to a novel ST ST11351. A total of 66.7% isolates were positive for β-lactamase genes with 58.3% harboring the blaTEM1B gene and a single isolate the blaCTX−M−14 and blaCTX−M−55 extended-spectrum β-lactamase (ESBL) genes. One isolate was positive for the mcr-9 mobilized colistin resistance gene. Most antibiotic resistance genes (ARGs) were associated with mobile genetic support: class 1 integrons (In22, In54, In191, and In369), insertion sequences (ISs), and/or transposons (Tn402 or Tn21). A total of 31 virulence genes were identified across the study isolates, including those responsible for adhesion (lpfA, iha, and aggR), immunity (air, gad, and iss), and toxins (senB, vat, astA, and sat). The virulence genes were mostly associated with IS (IS1, IS3, IS91, IS66, IS630, and IS481) or prophages. Co-resistance to heavy metal/biocide, antibiotics were evident in several isolates. The phylogenomic analysis with South African E. coli isolates from different sources (animals, birds, and humans) revealed that isolates from this study mostly clustered with clinical isolates. Phylogenetics linked with metadata revealed that isolates did not cluster according to source but according to ST. The occurrence of pathogenic and MDR isolates in the WWTP effluent and the associated river is a public health concern.
Immune Protective Evaluation Elicited by DNA Vaccination With Neospora caninum Dense Granules Proteins in Mice
Authors: Yu Guili , Liang Wei , Yang Qiankun , Wang Jinxin , Wang Yu , Zhang Tianmeng , Zhang Xiao , Fan Hui , Zhao Panpan , Cao Lili , Dong Jingquan
Published: February 2021

Neospora caninum, an obligate intracellular protozoan, is the major cause for neosporosis and brings serious economic losses to cattle breeding industries worldwide. After invasion, dense granules proteins are abundantly secreted and being important components of parasitophorous vacuole and intravacuolar network where N. caninum survives and replicates. The aim of the present study was to evaluate the protective immunity induced by DNA vaccines with genes encoding dense granules proteins 1 (GRA1), GRA4, GRA9, GRA14, GRA17, and GRA23 against N. caninum tachyzoites in BALB/C mice. Eukaryotic expressing plasmids of pcNcGRAs were constructed and the mice were intramuscularly immunized with pcNcGRAs followed by challenging infection with lethal doses of N. caninum. Immune responses were evaluated through monitoring the levels of serum antibodies, measurement of lymphocyte proliferation, and secretion of cytokines. Immune protection assays were carried out through monitoring survival time, body weight, and parasite burden in the brains. Results showed that all the pcNcGRA DNA vaccines could trigger remarkably specific humoral and cellular responses, with higher levels of IgG and IgG2a antibodies as well as obviously increased secretion of Th1-type IFN-γ cytokines. The immune protective efficacy revealed that pcNcGRA4, pcNcGRA14, and pcNcGRA17 DNA vaccines could individually increase the survival rate to 50, 37.5, and 25% in comparison with 0% in the control group; prolong the survival time more than 20.88 ± 11.12, 18.88 ± 10.83, and 16.63 ± 10.66 days compared with the control group of 4 ± 1.31 days; and decrease parasite burden in the brains to 297.63 ± 83.77, 471.5 ± 110.74, and 592.13 ± 102.2 parasites/100 ng comparing with 1221.36 ± 269.59 parasites/100 ng in the control group. These findings indicated that NcGRA4, NcGRA14, and NcGRA17 are potential vaccine candidates; NcGRA4 displayed better performance in immune protective efficacy and could be further combined with other advantageous antigens applied to the development of safe and effective DNA vaccines against N. caninum.
The Nefarious Hierarchy: An Alternative New Theory of the Firm
Authors: Arend Richard J.
Published: February 2021

We propose a new theory of the firm based on the premise that ‘the firm’ characterizes a factor-integrative form of doing business that is often the most effective and efficient structure for doing well by doing bad. We define the terms and requirements involved for such a theory, and fulfill those requirements by explaining what it is ‘to do bad’, and why and when the firm form is especially fitted to that. We do so by building upon basic premises about ‘bad-ness’ and by leveraging the logic of market failures. From this base, we argue a new reason for the firm form to exist and yet be limited in its growth. This leads to six related propositions regarding the relationships between ‘bad’ firms, tolerant contexts and realized social harms. We discuss how to test the ideas, and what the implications are for research on the firm, strategy and entrepreneurship.
Generation and Mitigation Mechanism Studies of Nonlinear Thermoacoustic Instability in a Modelled Swirling Combustor with a Heat Exchanger
Authors: Sun Yuze , Zhao Dan , Zhu Xiaowei
Published: February 2021

In the present work, 3D Unsteady Reynolds-Averaged Navier-Stokes (URANS) simulations are performed to investigate the generation and mitigation mechanism of combustion-sustained thermoacoustic instabilities in a modelled swirl combustor. The effects of (1) swirling number SN, (2) inlet air flow rate Va and (3) inlet temperature Ti on the amplitudes and frequencies of swirling combustion-excited limit cycle oscillations are examined. It is found that the amplitude of acoustic fluctuations is increased with increasing SN and Va and decreased with the increase of Ti. The dominant frequency of oscillations is also found to increases with the increase of SN and Va. However, increasing Ti leads to the dominant frequency being decreased first and then increased. An alternative passive control method of installing an adjustable temperature heat exchanger on the combustion chamber wall is then proposed. Numerical results show that thermoacoustic oscillations could be excited and mitigated by setting the heat exchanger temperature to TH. Global and local Rayleigh indexes are applied to further reveal the excitation and attenuation effects on mechanisms. The present study is conducive to developing a simulation platform for thermoacoustic instabilities in swirling combustors. It also provides an alternative method to amplify or mitigate thermoacoustic oscillations.
Assessing Baseline Carbon Stocks for Forest Transitions: A Case Study of Agroforestry Restoration from Hawaiʻi
Authors: Melone Angelica , Bremer Leah L. , Crow Susan E. , Hastings Zoe , Winter Kawika B. , Ticktin Tamara , Rii Yoshimi M. , Wong Maile , Kukea-Shultz Kānekoa , Watson Sheree J. , Trauernicht Clay
Published: February 2021

As the extent of secondary forests continues to expand throughout the tropics, there is a growing need to better understand the ecosystem services, including carbon (C) storage provided by these ecosystems. Despite their spatial extent, there are limited data on how the ecosystem services provided by secondary forest may be enhanced through the restoration of both ecological and agroecological functions in these systems. This study quantifies the above- and below-ground C stocks in a non-native secondary forest in Hawaiʻi where a community-based non-profit seeks to restore a multi-strata agroforestry system for cultural and ecological benefits. For soil C, we use the equivalent soil mass method both to estimate stocks and examine spatial heterogeneity at high resolution (eg. sub 5 m) to define a method and sampling design that can be replicated to track changes in C stocks on-site and elsewhere. The assessed total ecosystem C was ~388.5 Mg C/ha. Carbon stock was highest in trees (~192.4 Mg C/ha; ~50% of total C); followed by soil (~136.4 Mg C/ha; ~35% of total C); roots (~52.7 Mg C/ha; ~14% of total C); and was lowest in coarse woody debris (~4.7 Mg C/ha; ~1% of total C) and litter (~2.3 Mg C/ha; <1% of total C). This work provides a baseline carbon assessment prior to agroforest restoration that will help to better quantify the contributions of secondary forest transitions and restoration efforts to state climate policy. In addition to the role of C sequestration in climate mitigation, we also highlight soil C as a critical metric of hybrid, people-centered restoration success given the role of soil organic matter in the production of a suite of on- and off-site ecosystem services closely linked to local sustainable development goals.
Germination of Salicornia bigelovii (Torr.) under Shrimp Culture Effluents and the Application of Vermicompost Leachate for Mitigating Salt Stress
Authors: García-Galindo Emilio , Nieto-Garibay Alejandra , Troyo-Diéguez Enrique , Lucero-Vega Gregorio , Murillo-Amador Bernardo , Ruiz-Espinoza Francisco Higinio , Fraga-Palomino Héctor Cirilo
Published: February 2021

Attenuators of salt-stress favor the use of effluents, being a low-cost organic product. The present study aimed to evaluate the effect of vermicompost leachate (VL) added to shrimp-culture effluent on seeds and seedlings of Salicornia bigelovii (Torr.) under salt-stress, evaluating germination, water relations variables, and biomass. Seeds were irrigated with distilled water (DW) (CE: 0.0027 dS m−1), freshwater (FW) (CE: 1.36 dS m−1), seawater (SW) (CE: 55.83 dS m−1), shrimp residual water (SRW) (CE: 59.85 dS m−1), and with the same water sources but adding VL in 1:20 v/v. The means for the index of germination rate (IGR), germination energy (GE), and germination time (MGT) were higher with DW, DWVL, FW, and FWVL, decreasing with the others (p ≤ 0.05). In seedlings, the lowest water potential (Ψw) and osmotic potential (Ψs) were observed with SW, SWVL, SRW, and SRWVL (p ≤ 0.05), evidencing higher stress but the highest relative water content (RWC). The fresh and dry biomass increased and showed significant differences with SRW, and adding VL (DWVL, FWVL, SWVL, and SRWVL) acted as an effective attenuator of salt-stress. The response of water relations variables suggested an osmotic adjustment for mitigating the salt-stress in seedlings, lowering the Ψw and Ψs but increasing the RWC.
Impacts of Fallow Conditions, Compost and Silicate Fertilizer on Soil Nematode Community in Salt–Affected Paddy Rice Fields in Acid Sulfate and Alluvial Soils in the Mekong Delta, Vietnam
Authors: Sinh Nguyen Van , Khoi Chau Minh , Phuong Nguyen Thi Kim , Linh Tran Ba , Minh Dang Duy , Perry Roland N. , Toyota Koki
Published: February 2021

Avoidance of intensive rice cultivation (IRC) and soil amendments are potential practices to enhance soil properties. There is only limited information on the effects of reduced IRC and its mixture with compost or silicate fertilizer (Si) on the soil nematode community in salt–affected soils. This study aimed to assess the shifts of soil nematode community by reducing a rice crop from triple rice system (RRR) to a double rice system and mixed with compost or Si in paddy fields in acid sulfate soil (ASS) and alluvial soil (AL) in the Mekong Delta, Vietnam. Field experiments were designed with four treatments in four replicates, including RRR and a proposed system of double–rice followed by a fallow (FRR) and with 3 Mg ha–1 crop−1 compost or 100 kg ha–1 crop−1 Si. Soils were collected at harvest after the 2 year experiment, reflecting the fifth and third consecutive rice crop in RRR and FRR system, respectively. Results showed that reduced IRC gave a significant reduction in abundance of plant–parasitic nematodes (PPN), dominated by Hirschmanniella and increased abundance bacterivorous nematodes when mixed to compost and silicate fertilizer in ASS. In addition, reduced IRC increased nematode biodiversity Hill’s indices and reduced herbivorous footprint in ASS. Proposed system having compost or Si had strongly increased in bacterivorous and omnivorous footprints. Particularly, reduced IRC mixture with Si increased abundance of Rhabdolaimus, Mesodorylaimus and Aquatides, metabolic footprints (structure footprint, bacterivorous, omnivorous and predator) and diversity Hill’s N1 index in ASS. Our results highlighted that reduced IRC was a beneficial practice for decreasing abundance of PPN in salt-affected soils and increasing abundance of FLN in ASS. IRC mixture with compost or Si had potential in structuring the nematode communities with increasing biodiversity, trophic structure, and metabolic footprints.
Soil Properties Prediction for Precision Agriculture Using Visible and Near-Infrared Spectroscopy: A Systematic Review and Meta-Analysis
Authors: Ahmadi Arman , Emami Mohammad , Daccache Andre , He Liuyue
Published: February 2021

Reflectance spectroscopy for soil property prediction is a non-invasive, fast, and cost-effective alternative to the standard laboratory analytical procedures. Soil spectroscopy has been under study for decades now with limited application outside research. The recent advancement in precision agriculture and the need for the spatial assessment of soil properties have raised interest in this technique. The performance of soil spectroscopy differs from one site to another depending on the soil’s physical composition and chemical properties but it also depends on the instrumentation, mode of use (in-situ/laboratory), spectral range, and data analysis methods used to correlate reflectance data to soil properties. This paper uses the systematic review procedure developed by the Centre for Evidence-Based Conservation (CEBC) for an evidence-based search of soil property prediction using Visible (V) and Near-InfraRed (NIR) reflectance spectroscopy. Constrained by inclusion criteria and defined methods for literature search and data extraction, a meta-analysis is conducted on 115 articles collated from 30 countries. In addition to the soil properties, findings are also categorized and reported by different aspects like date of publication, journals, countries, employed regression methods, laboratory or in-field conditions, spectra preprocessing methods, samples drying methods, spectroscopy devices, wavelengths, number of sites and samples, and data division into calibration and validation sets. The arithmetic means of the coefficient of determination (R2) over all the reports for different properties ranged from 0.68 to 0.87, with better predictions for carbon and nitrogen content and lower performance for silt and clay. After over 30 years of research on using V-NIR spectroscopy to predict soil properties, this systematic review reveals solid evidence from a literature search that this technology can be relied on as a low-cost and fast alternative for standard methods of soil properties prediction with acceptable accuracy.