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Open AccessCommunication
Unexpected Metal-Free Dehydrogenation of a β-Ketoester to a Phenol Using a Recyclable Oxoammonium Salt
Molbank 2021, 2021(1), M1180; https://doi.org/10.3390/M1180 (registering DOI) - 13 Jan 2021
Abstract
The conversion of ethyl 2-oxocyclohexanecarboxylate to ethyl salicylate using an oxoammonium salt is reported. The dehydrogenation reaction is operationally simple and compares favorably with previous literature examples for the same transformation and expands the scope of oxoammonium salts as reagents for oxidative functionalization [...] Read more.
The conversion of ethyl 2-oxocyclohexanecarboxylate to ethyl salicylate using an oxoammonium salt is reported. The dehydrogenation reaction is operationally simple and compares favorably with previous literature examples for the same transformation and expands the scope of oxoammonium salts as reagents for oxidative functionalization processes. Full article
(This article belongs to the Special Issue Molecules from Side Reactions II)
Open AccessProceedings
Characterization of the Plant-Associated Bacterial Microbiota of the Mexican Medicinal Species Bouvardia ternifolia
Proceedings 2020, 66(1), 34; https://doi.org/10.3390/proceedings2020066034 (registering DOI) - 13 Jan 2021
Abstract
Though therapeutic compounds can be extracted directly from medicinal plant tissues; it is now known that many phytotherapeutic compounds are actually produced by associated microorganisms or due to their interaction with the plant. Bouvardia ternifolia is a medicinal plant that can be considered [...] Read more.
Though therapeutic compounds can be extracted directly from medicinal plant tissues; it is now known that many phytotherapeutic compounds are actually produced by associated microorganisms or due to their interaction with the plant. Bouvardia ternifolia is a medicinal plant that can be considered a potential source of therapeutic compounds, such as the antitumoral molecule bouvardin. We characterized the endophytic, endophytic+epiphyte and soil bacterial microbiota in the flower, leaves, stems and roots in specimens of this plant through 16S rDNA sequencing. We found that Proteobacteria followed by Actinobacteria were the most abundant bacteria phyla in this plant. On the other hand, the most representative genera living endophytically were Propionibacterium, Paraccocus, Lactobacillus, Kaistobacter, Methylobacterium and Erwinia. This study provides evidence of the composition and diversity of the bacterial communities present in soil and tissues of B. ternifolia which can be considered for subsequent analysis and understanding of the therapeutic compounds that give this species its medicinal properties. Full article
Open AccessArticle
The Impacts of Dam Construction and Removal on the Genetics of Recovering Steelhead (Oncorhynchus mykiss) Populations across the Elwha River Watershed
Genes 2021, 12(1), 89; https://doi.org/10.3390/genes12010089 (registering DOI) - 13 Jan 2021
Abstract
Dam construction and longitudinal river habitat fragmentation disrupt important life histories and movement of aquatic species. This is especially true for Oncorhynchus mykiss that exhibits both migratory (steelhead) and non-migratory (resident rainbow) forms. While the negative effects of dams on salmonids have been [...] Read more.
Dam construction and longitudinal river habitat fragmentation disrupt important life histories and movement of aquatic species. This is especially true for Oncorhynchus mykiss that exhibits both migratory (steelhead) and non-migratory (resident rainbow) forms. While the negative effects of dams on salmonids have been extensively documented, few studies have had the opportunity to compare population genetic diversity and structure prior to and following dam removal. Here we examine the impacts of the removal of two dams on the Elwha River on the population genetics of O. mykiss. Genetic data were produced from >1200 samples collected prior to dam removal from both life history forms, and post-dam removal from steelhead. We identified three genetic clusters prior to dam removal primarily explained by isolation due to dams and natural barriers. Following dam removal, genetic structure decreased and admixture increased. Despite large O. mykiss population declines after dam construction, we did not detect shifts in population genetic diversity or allele frequencies of loci putatively involved in migratory phenotypic variation. Steelhead descendants from formerly below and above dammed populations recolonized the river rapidly after dam removal, suggesting that dam construction did not significantly reduce genetic diversity underlying O. mykiss life history strategies. These results have significant evolutionary implications for the conservation of migratory adaptive potential in O. mykiss populations above current anthropogenic barriers. Full article
(This article belongs to the Special Issue Genetics and Genomics of Salmonid Fishes)
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Open AccessRetraction
Retraction: Middleton, B. and Cosgrove, S.M. Isolation and Elimination of Latent and Productive Herpes Simplex Virus from the Sacral and Trigeminal Ganglions. Proceedings 2020, 50, 92
Proceedings 2020, 50(1), 150; https://doi.org/10.3390/proceedings2020050150 (registering DOI) - 13 Jan 2021
Abstract
The Proceedings Editorial Office has been made aware that there is fake affiliation information. [...] Full article
Open AccessArticle
A Population-Based Retrospective Study of Biliary Tract Cancers in Alberta, Canada
Curr. Oncol. 2021, 28(1), 417-427; https://doi.org/10.3390/curroncol28010044 (registering DOI) - 13 Jan 2021
Abstract
Background: Biliary tract cancers (BTC) are uncommon malignancies and are underrepresented in the literature. Methods: We performed a retrospective population-based review of adult patients with biopsy-confirmed BTC in Alberta from 2000 to 2015. Demographic data, risk factors, symptoms, treatment, and staging data were [...] Read more.
Background: Biliary tract cancers (BTC) are uncommon malignancies and are underrepresented in the literature. Methods: We performed a retrospective population-based review of adult patients with biopsy-confirmed BTC in Alberta from 2000 to 2015. Demographic data, risk factors, symptoms, treatment, and staging data were collected and analyzed. Survival analyses were completed. Results: A total of 1604 patients were included in our study, of which 766 (47.8%) were male. The median age at diagnosis was 68 (range 19–99). There were 374 (23.3%) patients with resectable tumors at diagnosis versus 597 (37.2%) with unresectable tumors. Of the patients, 380 (21.5%) received chemotherapy (CT) and 81 (5.0%) underwent radiation therapy. There was a clear trend with worsening stage and performance status associated with shorter median overall survival (OS). Ampulla of Vater tumors had the best median OS (25.69 months), while intrahepatic bile duct cancers had the worst (5.78 months). First-line palliative CT regimens included gemcitabine+cisplatin (OS 14.98 months (mo), n = 212), single agent gemcitabine (OS 12.42 mo, n = 22), capecitabine (OS 8.12 mo, n = 8), and capecitabine+gemcitabine (OS 6.93 mo, n = 13). Patients with advanced or metastatic disease who received first-line gemcitabine+cisplatin had a median OS of 11.8 months (n = 119). Conclusion: BTCs have poor survival. Worse outcomes occur in higher stage and poorer Eastern Cooperative Oncology Group (ECOG) performance status patients across all tumor subtypes. Tumor resectability at diagnosis was associated with better OS. Our study supports the use of gemcitabine+cisplatin as a combination first-line palliative CT, as patients treated in Alberta have a comparable OS to that reported in the ABC-02 phase III study. Full article
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Open AccessArticle
National Thoracic Surgery Standards Implementation: Barriers, Enablers, and Opportunities
Curr. Oncol. 2021, 28(1), 405-416; https://doi.org/10.3390/curroncol28010043 (registering DOI) - 13 Jan 2021
Abstract
Background: Diagnosis and surgical treatment decision making for thoracic cancers is complex. Moreover, there is demonstrated variability in how each province in Canada delivers cancer care, resulting in disparities in patient outcomes. Recently, the Canadian Partnership Against Cancer (CPAC) published pan-Canadian evidence-based standards [...] Read more.
Background: Diagnosis and surgical treatment decision making for thoracic cancers is complex. Moreover, there is demonstrated variability in how each province in Canada delivers cancer care, resulting in disparities in patient outcomes. Recently, the Canadian Partnership Against Cancer (CPAC) published pan-Canadian evidence-based standards for the care of thoracic surgery cancer patients. This study was undertaken to assess the degree to which these standards were currently met in practice and to further understand the determinants to their implementation nationally. Methods: This study was undertaken in two parts: (1) a national survey of thoracic surgeons to assess the perceived extent of implementation of these standards in their institution and province; and (2) formation of a focus group with a representative sample of thoracic surgeons across Canada in a qualitative study to understand the determinants of successful standards implementation. Results: 37 surgeons (33% response rate) participated in the survey; 78% were from academic hospitals. The top categories of standards that were under-implemented included (a) quality assurance processes, data collection and clinician audit and feedback, and (b) ongoing regional planning and workload assessments for thoracic surgeons, and (c) pathology turnaround time target of two weeks and the use of a standardized synoptic pathology report format. Enablers, barriers, and opportunities for standards implementation contextualized the discussion within the focus group. Conclusion: Study results demonstrated variation in the implementation of surgery standards across Canada and identified the determinants to the delivery of high quality surgical care. Future work will need to include the promotion and development of quality improvement strategies and effective resource allocation that is aligned with the implementation of thoracic cancer surgery standards in order to improve patient outcomes. Full article
Open AccessReview
Success Rates of Monitoring for Healthcare Professionals with a Substance Use Disorder: A Meta-Analysis
J. Clin. Med. 2021, 10(2), 264; https://doi.org/10.3390/jcm10020264 (registering DOI) - 13 Jan 2021
Abstract
In the past decades, monitoring programs have been developed for healthcare professionals with substance use disorders. We aimed to explore estimates of abstinence and work retention rates after participation in such monitoring programs. A literature search was performed using PubMed, Embase, PsycINFO, and [...] Read more.
In the past decades, monitoring programs have been developed for healthcare professionals with substance use disorders. We aimed to explore estimates of abstinence and work retention rates after participation in such monitoring programs. A literature search was performed using PubMed, Embase, PsycINFO, and CINAHL. Twenty-nine observational studies reporting on success rates (abstinence and work retention) of monitoring for healthcare professionals with a substance use disorder were included in the meta-analysis. Quality-effects models calculated pooled success rates and corresponding 95%-Confidence Intervals (CI), with subgroup analyses on monitoring elements and patient characteristics. Pooled success rates were 72% for abstinence (95%-CI = 63–80%) and 77% for work retention (95%-CI = 61–90%). Heterogeneity across studies was partly explained by the starting moment of monitoring, showing higher abstinence rates for studies that started monitoring after treatment completion (79%; 95%-CI = 72–85%) compared to studies that started monitoring with treatment initiation (61%; 95%-CI = 50–72%). About three-quarters of healthcare professionals with substance use disorders participating in monitoring programs are abstinent during follow-up and working at the end of the follow-up period. Due to selection and publication bias, no firm conclusions can be drawn about the effectiveness of monitoring for healthcare professionals with SUD. Full article
(This article belongs to the Special Issue Addictive Disorders and Clinical Psychiatry)
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Open AccessProceedings
Temporal Changes and Alternating Host Tree Root and Shoot Growth Affect Soil Microbiomes
Proceedings 2020, 66(1), 35; https://doi.org/10.3390/proceedings2020066035 (registering DOI) - 13 Jan 2021
Abstract
Patterns of trees’ endogenous rhythmic growth (ERG) and paralleled C allocation shift between root and shoot systems have been studied, but there is still a need to understand their impact in shaping soil microbiomes. Moreover, the impact of plants on soil microbial communities [...] Read more.
Patterns of trees’ endogenous rhythmic growth (ERG) and paralleled C allocation shift between root and shoot systems have been studied, but there is still a need to understand their impact in shaping soil microbiomes. Moreover, the impact of plants on soil microbial communities can be modulated or overweighed by time-induced plant and/or seasonal changes. Thus, we intended to analyze the structure of soil microbiomes as response to simultaneous alternated host tree root and shoot flushes and time-induced changes within one vegetation period at two sites in Central Germany. In this study, we utilized oak phytometers (Quercus robur L., clone DF159) as host trees, and made use of their ERG, whereby consecutive root and shoot flushes make a complete growth cycle. We studied two complete growth cycles during the same vegetation period, performed a non-destructive soil sampling and applied high-throughput amplicon sequencing of the bacterial 16S gene and the fungal ITS2 region. As C allocation shifts between the tree root and shoot, released root exudates and consequently the nutrient availability alternate for soil microorganisms. We therefore anticipated different microbial communities in the host tree root zone along the growth cycles until autumnal leaf senescence. In our results, the bacterial community exhibited a directional change over time along the vegetation period. In contrast, the fungal community appeared sample specific. Our findings enlarge the current understanding of the temporal microbial assembly in the host tree root zone. Full article
Open AccessArticle
Bidirectional Power Sharing for DC Microgrid Enabled by Dual Active Bridge DC-DC Converter
Energies 2021, 14(2), 404; https://doi.org/10.3390/en14020404 (registering DOI) - 13 Jan 2021
Abstract
Currently, high-performance power conversion requirements are of increasing interest in microgrid applications. In fact, isolated bidirectional dc-dc converters are widely used in modern dc distribution systems. The dual active bridge (DAB) dc-dc converter is identified as one of the most promising converter topology [...] Read more.
Currently, high-performance power conversion requirements are of increasing interest in microgrid applications. In fact, isolated bidirectional dc-dc converters are widely used in modern dc distribution systems. The dual active bridge (DAB) dc-dc converter is identified as one of the most promising converter topology for the mentioned applications, due to its benefits of high power density, electrical isolation, bidirectional power flow, zero-voltage switching, and symmetrical structure. This study presents a power management control scheme in order to ensure the power balance of a dc microgrid in stand-alone operation, where the renewable energy source (RES) and the battery energy storage (BES) unit are interfaced by DAB converters. The power management algorithm, as introduced in this work, selects the proper operation of the RES system and BES system, based on load/generation power and state-of-charge of the battery conditions. Moreover, a nonlinear robust control strategy is proposed when the DAB converters are in voltage-mode-control in order to enhance the dynamic performance and robustness of the common dc-bus voltage, in addition to overcoming the instability problems that are caused by constant power loads and the dynamic interactions of power electronic converters. The simulation platform is developed in MATLAB/Simulink, where a photovoltaic system and battery system are selected as the typical RES and BES, respectively. Assessments on the performance of the proposed control scheme are conducted. Comparisons with the other control method are also provided. Full article
(This article belongs to the Section Smart Grids and Microgrids)
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Open AccessArticle
Experimental Analysis of Ultrasonic Multiple Scattering Attenuation through the Air with Fine Dust
Appl. Sci. 2021, 11(2), 694; https://doi.org/10.3390/app11020694 (registering DOI) - 13 Jan 2021
Abstract
In this study, we experimentally evaluated the application of multiple scattering theory for measuring ultrasonic attenuation. Based on the independent approximation theory, the method adopted for calculating the attenuation of coherent waves through air with fine dust is discussed. To obtain a scattering [...] Read more.
In this study, we experimentally evaluated the application of multiple scattering theory for measuring ultrasonic attenuation. Based on the independent approximation theory, the method adopted for calculating the attenuation of coherent waves through air with fine dust is discussed. To obtain a scattering wavefield, a unique ultrasonic scattering hardware was developed, and signal processing schemes were suggested. Four cases of standard particle doses (0, 0.004, 0.008, and 0.012 g) were investigated inside a chamber. The results obtained from the experiments demonstrate that the proposed signal processing approach successfully calculates the scattering attenuation, which correlates well with the applied doses of fine dust. In addition, we discuss the irregular shape and composition of fine dust relative to the scattering cross-section. Full article
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Open AccessEditorial
Acknowledgment to Reviewers of Environments in 2020
Environments 2021, 8(1), 5; https://doi.org/10.3390/environments8010005 (registering DOI) - 13 Jan 2021
Abstract
Peer review is the driving force of journal development, and reviewers are gatekeepers who ensure that Environments maintains its standards for the high quality of its published papers [...] Full article
Open AccessArticle
Facets of Impulsivity in Relation to Diet Quality and Physical Activity in Adolescence
Int. J. Environ. Res. Public Health 2021, 18(2), 613; https://doi.org/10.3390/ijerph18020613 - 12 Jan 2021
Abstract
Although the construct of impulsivity has generally been found to be associated with obesity and health behaviors in adults, research among adolescents is more limited and studies have yet to elucidate which facets of impulsivity may be most salient with regard to different [...] Read more.
Although the construct of impulsivity has generally been found to be associated with obesity and health behaviors in adults, research among adolescents is more limited and studies have yet to elucidate which facets of impulsivity may be most salient with regard to different eating and physical activity behaviors. Therefore, the present cross-sectional study assessed facets of impulsivity, measured by the UPPS-P questionnaire, in relation to health behaviors among adolescents. A sample of 2797 high school students from Los Angeles, California completed self-report measures during the ninth grade. The UPPS-P subscales (i.e., (lack of) premeditation, sensation seeking, (lack of) perseverance, negative urgency, positive urgency) were examined as predictors of unhealthy diet quality (i.e., frequency of consumption of high-fat foods and sweet food and drinks, measured by the National Cancer Institute (NCI) Quick Food Scan) and frequency of vigorous physical activity (measured by the Youth Risk Behavior Surveillance System). Greater sensation seeking, positive urgency, and negative urgency was associated with greater unhealthy diet quality (ps < 0.001). Greater negative urgency and lack of perseverance was associated with less frequent vigorous physical activity, whereas greater sensation seeking, lack of premeditation, and positive urgency was associated with more frequent vigorous physical activity (ps < 0.05). While negative urgency (i.e., impulsivity in the context of negative emotions) was consistently associated with poor health behaviors, other facets of impulsivity may potentiate vigorous physical activity in youth. Together these findings underscore the importance of considering the multidimensional nature of impulsivity in relation to adolescents’ health behaviors and highlight areas for future longitudinal research. Full article
(This article belongs to the Special Issue Risk and Maintenance of Obesity and Eating Disorders in Adolescents)
Open AccessArticle
Keeping a Critical Eye on Majority Language Influence: The Case of Uptalk in Heritage Spanish
Languages 2021, 6(1), 13; https://doi.org/10.3390/languages6010013 - 12 Jan 2021
Abstract
The goal of this study is to highlight the importance of taking into account variations in monolingual grammars before discussing majority language influence as a possible source of heritage speakers’ divergent grammars. In this study, we examine the production of uptalk in Spanish [...] Read more.
The goal of this study is to highlight the importance of taking into account variations in monolingual grammars before discussing majority language influence as a possible source of heritage speakers’ divergent grammars. In this study, we examine the production of uptalk in Spanish by heritage speakers of Mexican Spanish in Southern California. Uptalk (i.e., rising intonation contour at the end of a non-question utterance) is frequently associated with California English. Thus, heritage speakers’ use of uptalk is often considered to be influenced from English intonation (i.e., the majority language). Although uptalk in Spanish is not well understood, it has been observed in Mexican Spanish, which calls attention to the importance of investigating uptalk in monolingual Spanish. Using a dyadic interaction task, we obtained spontaneous speech data of 16 heritage speakers and 16 monolingual speakers of Mexican Spanish and compared the phonological and phonetic properties of uptalks produced by the two groups. Our results demonstrated that the heritage speakers and the monolingual speakers produced uptalks with similar frequencies and mainly used L+H* HH% and L* HH% contours. However, the two groups had more differences than similarities. Specifically, heritage speakers’ uptalks presented less dynamic contours and were produced with flatter rises than monolinguals’ uptalks. Heritage speakers’ divergent patterns showed close resemblance with patterns in English, suggesting majority language influence as a valid source of divergence. We discuss possible avenues for future research for a better understanding of the role of majority language influence on heritage Spanish uptalk. Full article
(This article belongs to the Special Issue Contemporary Advances in Linguistic Research on Heritage Spanish)
Open AccessReview
Haemogregarines and Criteria for Identification
Animals 2021, 11(1), 170; https://doi.org/10.3390/ani11010170 - 12 Jan 2021
Abstract
Apicomplexa is a phylum that includes all parasitic protozoa sharing unique ultrastructural features. Haemogregarines are sophisticated apicomplexan blood parasites with an obligatory heteroxenous life cycle and haplohomophasic alternation of generations. Haemogregarines are common blood parasites of fish, amphibians, lizards, snakes, turtles, tortoises, crocodilians, [...] Read more.
Apicomplexa is a phylum that includes all parasitic protozoa sharing unique ultrastructural features. Haemogregarines are sophisticated apicomplexan blood parasites with an obligatory heteroxenous life cycle and haplohomophasic alternation of generations. Haemogregarines are common blood parasites of fish, amphibians, lizards, snakes, turtles, tortoises, crocodilians, birds, and mammals. Haemogregarine ultrastructure has been so far examined only for stages from the vertebrate host. PCR-based assays and the sequencing of the 18S rRNA gene are helpful methods to further characterize this parasite group. The proper classification for the haemogregarine complex is available with the criteria of generic and unique diagnosis of these parasites Full article
Open AccessArticle
Future Changes in Wave Conditions at the German Baltic Sea Coast Based on a Hybrid Approach Using an Ensemble of Regional Climate Change Projections
Water 2021, 13(2), 167; https://doi.org/10.3390/w13020167 - 12 Jan 2021
Abstract
In this study, the projected future long-term changes of the local wave conditions at the German Baltic Sea coast over the course of the 21st century are analyzed and assessed with special focus on model agreement, statistical significance and ranges/spread of the results. [...] Read more.
In this study, the projected future long-term changes of the local wave conditions at the German Baltic Sea coast over the course of the 21st century are analyzed and assessed with special focus on model agreement, statistical significance and ranges/spread of the results. An ensemble of new regional climate model (RCM) simulations with the RCM REMO for three RCP forcing scenarios was used as input data. The outstanding feature of the simulations is that the data are available with a high horizontal resolution and at hourly timesteps which is a high temporal resolution and beneficial for the wind–wave modelling. A new data interface between RCM output data and wind–wave modelling has been developed. Suitable spatial aggregation methods of the RCM wind data have been tested and used to generate input for the calculation of waves at quasi deep-water conditions and at a mean water level with a hybrid approach that enables the fast compilation of future long-term time series of significant wave height, mean wave period and direction for an ensemble of RCM data. Changes of the average wind and wave conditions have been found, with a majority of the changes occurring for the RCP8.5 forcing scenario and at the end of the 21st century. At westerly wind-exposed locations mainly increasing values of the wind speed, significant wave height and mean wave period have been noted. In contrast, at easterly wind-exposed locations, decreasing values are predominant. Regarding the changes of the mean wind and wave directions, westerly directions becoming more frequent. Additional research is needed regarding the long-term changes of extreme wave events, e.g., the choice of a best-fit extreme value distribution function and the spatial aggregation method of the wind data. Full article
(This article belongs to the Special Issue Effect of Climate Change on Coastal Hydrodynamics)
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