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The Colorado River is a vital water source for the western United States, yet the river is governed by disjointed and outdated policies that have left water management fragmented and water quantities overallocated. Groundwater is an overlooked component of Colorado River Basin (CRB) water supplies, making it vulnerable to overuse from disparities in uncoordinated protective management strategies. In this study, we analyzed state level groundwater policies to reveal the diversity and efficacy of groundwater governance mechanisms. The existing groundwater management plans for each state throughout the basin are fragmented and limited in scope. We found that with policies only covering 22% of the basin, they do not provide adequate protection at the basin scale for the sustainable use of groundwater resources in the face of increasing demands, creating a positive feedback loop that reinforces the scarcity issue. We conclude that a comprehensive management plan that can fully address resource use throughout the CRB is necessary for the sustainable use of groundwater and its contribution to base flow in the Colorado River. We suggest that such a plan could be derived through an interstate compact like the Colorado River Compact that is used for surface water management.

Background and aims – The species name Gymnosporia filiformis, validly published in a 1927 revision of South African Celastraceae, was based on syntypes representing both Maytenus cordata and a new species. Subsequent studies supported the distinction of Gymnosporia and Maytenus as separate genera. From 1984, this new species was provisionally referred to by the designation “Maytenus sp. A”. Maytenus in Africa comprises a diverse group of species not closely related to the New World members of Maytenus. Here, we clarify the taxonomic identity and generic placement of G. filiformis, and compare it with species with which it has historically been confused. Material and methods – Descriptions and observations are based on extensive field work, supported by conventional taxonomic methods, including study of relevant literature and herbarium collections. Key results – The name Gymnosporia filiformis is lectotypified using a syntype representing “Maytenus sp. A”. We describe a new monotypic genus, Marijordaania, to accommodate “Maytenus sp. A”, and propose the new combination, Marijordaania filiformis. An amended description is provided for the species. It is morphologically quite different from Maytenus cordata, but also from Maytenus acuminata and Maytenus abbottii, species with which it has been confused in the past. Marijordaania filiformis grows in the understorey of evergreen Scarp Forest and is relatively rare, known with certainty only from KwaZulu-Natal and the Eastern Cape provinces, South Africa. A preliminary conservation assessment suggests that M. filiformis should be classified as Endangered. Conclusion – Marijordaania filiformis is a taxonomically isolated species with no apparent close relatives among African Celastraceae. While the generic status of other African members of Maytenus still needs to be resolved, it would not impact the taxonomic status of Marijordaania. In a recent key for Celastraceae genera based on morphology and geography, M. filiformis ran to the genus Euonymus, but this association lacks support from available molecular evidence.

This research introduces a fractional high-order sliding mode control (FHOSMC) method that utilises an inverse integral fractional order, 0<β<1, as the high order on the FHOSMC reaching law, exhibiting a novel contribution in the related field of study. The application of the proposed approach into a bioreactor system via diffeomorphism operations demonstrates a notable improvement in the management of the bioreactor dynamics versus classic controllers. The numerical findings highlight an improved precision in tracking reference signals and an enhanced plant stability compared to proportional–integral–derivative (PID) controller implementations within challenging disturbance scenarios. The FHOSMC effectively maintains the biomass concentration at desired levels, reducing the wear of the system as well as implementation expenses. Furthermore, the theoretical analysis of the convergence within time indicates substantial potential for further enhancements. Subsequent studies might focus on extending this control approach to bioreactor systems that integrate sensor technologies and the formulation of adaptive algorithms for real-time adjustments of β-type fractional-orders.

In the field of breast cancer diagnosis, the precise classification of benign images plays a pivotal role in ensuring effective patient care. This research undertakes a detailed examination of EfficientNetV2 models, specifically focusing on their ability to discern benign histopathology breast cancer images. The dataset were carefully curated to include diverse benign cases such as adenosis, fibroadenoma, phyllodes_tumor, and tubular_adenoma of image level for 40X magnification factor underwent thorough preprocessing before being divided into training and testing sets. Various variants of the EfficientNetV2 model—EfficientNetV2B0, EfficientNetV2B1, EfficientNetV2B2, EfficientNetV2B3, EfficientNetV2S, EfficientNetV2M, and EfficientNetV2L—were trained on the designated dataset. The performance evaluation shows the intricacies of the efficiency of each model. Notably, EfficientNetV2L emerged as a standout performer, boasting impressive metrics such as Accuracy (0.97), Precision (0.97), Recall (0.97), F1-score (0.97). These findings underscore the potential of EfficientNetV2L as a robust tool for accurately discerning benign histopathology breast cancer images. This study contributes significant insights to the field of breast cancer diagnostics, particularly addressing the critical task of classifying benign cases accurately. The gained insights pave the way for improved decision-making in assessments, ultimately enhancing the overall efficacy of breast cancer diagnosis.

Abstract As geoscience and water related enrollment and degrees continue to decline, new methods are needed to recruit and engage students in these interesting and challenging interdisciplinary fields. An existing water-themed distinguished lecture tour was reinvented and reinvigorated to include a workshop to (1) promote interdisciplinary collaboration and (2) increase student engagement in earth sciences. The Geological Society of America has dedicated foundation support for a domestic and international lecture tour to promote the scientific discipline of hydrogeology. In addition to the lecture tour with a standard presentation and meetings with faculty, staff, and students, a half-day, interactive field demonstration of the inventory and assessment techniques for springs ecosystems was conducted at a spring near the lecture site. Local faculty hosts were encouraged to engage students in the planning and implementation of the demonstration workshop. The students were provided additional training to enter the interdisciplinary ecosystem data into a cloud-sourced database and to be actively engaged in producing a publication related to the springs ecosystems inventories and assessments. Of the participants of the demonstration workshops, students at eight of the host institutions became co-authors of the resulting manuscript. With the significant investment of time, resources, and logistics to implement a lecture tour, an additional interactive, hands-on, demonstration workshop is a cost-effective way to increase student engagement and provide interdisciplinary collaboration.

Se presenta un procedimiento de diseño para el control en modo deslizante de primer orden aplicado a un sistema en forma de cadena de integradores pura o perturbada, (forma canónica controlable perturbada). La ley de control se propone de forma novedosa. La magnitud de control se define directamente por los coeficientes del polinomio de la superficie de deslizamiento. Se muestra que este procedimiento minimiza en cierto sentido el esfuerzo de control para alcanzar la superficie diseñada. Los cálculos son aún más sencillos que los de las técnicas clásicas en modo deslizante. Además, la elección de una dinámica de superficie estable garantiza un tiempo de alcance finito a la misma. El esfuerzo de control y el castañeteo (chattering) son bajos. Las perturbaciones y términos conocidos que provocan inestabilidad se aprovechan en ciertas condiciones del alcance a la superficie. Se presentan simulaciones que ilustran los resultados y comparando el comportamiento de métodos de control en modo deslizante existentes en la literatura con el propuesto en este artículo.

Today, there is a fierce rivalry between ethnic groups in Nigeria on a number of issues, such as the division of power and resources, aversion to dominance, and uneven growth. Ethnicity as an identity naturally occupies a prominent position in the political arena. It is the simplest and most natural way for people to mobilize around essential human needs such as security, food, shelter, economical well-being, inequity, land distribution, autonomy, and recognition. Recent research has revealed the potential to determine an individual's ethnicity based on biometric data automatically. These studies reported significant advancements in automatically predicting demographics based on facial and iris traits. This success has been ascribed to the availability of a sufficient amount of high-quality data. There needs to be more data about the likelihood that fingerprints can disclose an individual's ethnicity. A need for more data causes this difficulty. This study aims to obtain fingerprint pictures via live scan among the major ethnic groups in Nigeria. For training and classification of the fingerprint images, the proposed Dynamic Horizontal Voting Ensemble (DHVE) deep learning with a Hybrid of Convolutional Neural Network (CNN) and Long Short-Term Memory (LSTM) as the base learner was employed. Standard performance classification metrics such as Accuracy, Recall, Precision, and F1 score were used to evaluate the performance analysis of the model. This study demonstrated an accuracy of over 98% in predicting a person's ethnicity. Additionally, the proposed model outperformed existing state-of-the-art models.

Abstract Background A well-qualified workforce is critical to effective functioning of health systems and populations; however, skill gaps present a challenge in low-resource settings. While an emerging body of evidence suggests that mentorship can improve quality, access, and systems in African health settings by building the capacity of health providers, less is known about its implementation in surgery. We studied a novel surgical mentorship intervention as part of a safe surgery intervention (Safe Surgery 2020) in five rural Ethiopian facilities to understand factors affecting implementation of surgical mentorship in resource–constrained settings. Methods We designed a convergent mixed-methods study to understand the experiences of mentees, mentors, hospital leaders, and external stakeholders with the mentorship intervention. Quantitative data was collected through a survey (n = 25) and qualitative data through in-depth interviews (n = 26) in 2018 to gather information on (1) intervention characteristics including areas of mentorship, mentee-mentor relationships, and mentor characteristics, (2) organizational context including facilitators and barriers to implementation, (3) perceived impact, and (4) respondent characteristics. We analyzed the quantitative and qualitative data using frequency analysis and the constant comparison method, respectively; we integrated findings to identify themes. Results All mentees (100%) experienced the intervention as positive. Participants perceived impact as: safer and more frequent surgical procedures, collegial bonds between mentees and mentors, empowerment among mentees, and a culture of continuous learning. Over 70% of all mentees reported their confidence and job satisfaction increased. Supportive intervention characteristics included a systems focus, psychologically safe mentee-mentor relationships, and mentor characteristics including generosity with time and knowledge, understanding of local context, and interpersonal skills. Supportive organizational context included a receptive implementation climate. Intervention challenges included insufficient clinical training, inadequate mentor support, and inadequate dose. Organizational context challenges included resource constraints and a lack of common understanding of the intervention. Conclusion We offer lessons for intervention designers, policy makers, and practitioners about optimizing surgical mentorship interventions in resource-constrained settings. We attribute the intervention’s success to its holistic approach, a receptive climate, and effective mentee-mentor relationships. These qualities, along with policy support and adapting the intervention through user feedback are important for successful implementation.

Tissue boundaries in our body separate organs and enable healing, but boundary mechanics are not well known. Here, the authors define mechanical rules for colliding cell monolayers and use these rules to make complex, predictable tessellations.

Relevance .This study examines the efforts of the Nigerian government towards managing the coronavirus infection. COVID-19 is an infectious disease that originated from Wuhang, China at the end of 2019. In the early stages, the virus infected about 300 people and caused the deaths of six people. Despite early detections and reactions by the Chinese government, the disease spread to the different countries of the world. By June 2021 more than 170 million (170,000,000) people have been infected with the disease with more than three million and sixty thousand (3,600,000) deaths. According to Johns Hopkins University in Nigeria, in June 2021, 167 thousand cases of diseases and more than 2 thousand deaths were registered. Materials and Methods . The study analyses data from open sources such as academic journals, books, newspapers and online sources. Results and Discussion. Findings of the study reveal that while the actions of the Nigerian government have been preventive, they have not curtailed the spread of the virus. Conclusion . The researchers recommend that the Nigerian government intensifies its efforts towards to limit the spread of the virus by effectively implementing lockdowns and bans on public gatherings, improve testing capacities to identify and isolate carriers of the virus.

Background Published randomized controlled trials are underpowered for binary clinical end points to assess the safety and efficacy of renin‐angiotensin system inhibitors (RASi) in adults with COVID‐19. We therefore performed a meta‐analysis to assess the safety and efficacy of RASi in adults with COVID‐19. Methods and Results MEDLINE, EMBASE, ClinicalTrials.gov, and the Cochrane Controlled Trial Register were searched for randomized controlled trials that randomly assigned patients with COVID‐19 to RASi continuation/commencement versus no RASi therapy. The primary outcome was all‐cause mortality at ≤30 days. A total of 14 randomized controlled trials met the inclusion criteria and enrolled 1838 participants (aged 59 years, 58% men, mean follow‐up 26 days). Of the trials, 11 contributed data. We found no effect of RASi versus control on all‐cause mortality (7.2% versus 7.5%; relative risk [RR], 0.95; [95% CI, 0.69–1.30]) either overall or in subgroups defined by COVID‐19 severity or trial type. Network meta‐analysis identified no difference between angiotensin‐converting enzyme inhibitors versus angiotensin II receptor blockers. RASi users had a nonsignificant reduction in acute myocardial infarction (2.1% versus 3.6%; RR, 0.59; [95% CI, 0.33–1.06]), but increased risk of acute kidney injury (7.0% versus 3.6%; RR, 1.82; [95% CI, 1.05–3.16]), in trials that initiated and continued RASi. There was no increase in need for dialysis or differences in congestive cardiac failure, cerebrovascular events, venous thromboembolism, hospitalization, intensive care admission, inotropes, or mechanical ventilation. Conclusions This meta‐analysis of randomized controlled trials evaluating angiotensin‐converting enzyme inhibitors/angiotensin II receptor blockers versus control in patients with COVID‐19 found no difference in all‐cause mortality, a borderline decrease in myocardial infarction, and an increased risk of acute kidney injury with RASi. Our findings provide strong evidence that RASi can be used safely in patients with COVID‐19.

Rangelands in South Africa, Lesotho, and Eswatini contain a rich diversity of valuable fodder trees and shrubs. This research is the first attempt to document the regional diversity and distribution of these browse resources. Scientific publications, textbooks, databases, and published reports were accessed to compile a database of plant species that were recorded as utilised by ruminants and non-ruminants. Relevant forage attributes, such as functional traits as well as utilisation traits, were added to each species record. Thereafter, distribution records were extracted from the South African National Biodiversity Institute’s Botanical Database of South Africa and analysed with numerical techniques to establish phytogeographical patterns. A total of 613 plant species from 76 families have been recorded, which formed seven distinct phytochoria, termed the Central Arid, Eastern Subtropical, Highland Temperate, Moist Temperate, Northern Subtropical, Southern Temperate, and Western Arid browse-choria. Key families and species, as well as functional and utilisation traits, are discussed, focusing on key species present in the browse-choria. This browse database, together with the earlier compiled Leguminosae and Poaceae databases, will be used to prioritise indigenous southern African plant species/infraspecific taxa to be collected for the conservation of genetic resources and future evaluations for potential development as forage crops.

This paper provides a technical analysis of a river’s current and future resilience in a watershed with intensive agricultural and fishing activities. The study area was the last section of the Culiacan River corresponding to the river mouth over a lagoon system. Dissolved oxygen modeling was performed using the Streeter-Phelps model to evaluate the river self-depuration capability using Biochemical Oxygen Demand, dissolved oxygen, streamflow, and water temperature data from 2013 to 2020. Fieldwork was carried out to establish the geomorphological characteristics of the river by determining stream velocity, width, and depth and the location of nine sources of pollution on the river. The modeling was performed for three groups of months with different temperatures, identified by hierarchical cluster analysis. Estimates were made for future scenarios, assessing the effect of climate change on the Culiacan River’s self-depuration capability. The results showed that most of the year, the degradation rate of the system results in rapid assimilation of organic matter. However, the modeling indicates that the river would lose its resilience capability under climate change. Thus, it is essential to implement wastewater treatment systems to reduce the environmental impact on the aquatic ecosystem in the river and the lagoon system.

Objetivo: Determinar la correlación entre el resultado de la prueba de reacción en cadena de la polimerasa con transcriptasa reversa (RT-PCR) positiva con los hallazgos reportados por tomografía computarizada de alta resolución (TACAR) expresados en CO-RADS (COVID-19 Reporting and Data System) en pacientes con sospecha de enfermedad por coronavirus 2019 (COVID-19). Material y métodos: Incluimos 1,179 pacientes con definición operacional para COVID-19 en quienes se realizó RT-PCR y TACAR al inicio. Estudio retrospectivo, transversal, descriptivo y analítico de marzo a julio de 2020. Resultados: La mediana de edad fue de 57. El 54% de los hombres se afectó con mayor frecuencia, con igualdad en las varianzas. En TACAR la mayoría fue CO-RADS 1 y 5. En el 58% de pacientes la RT-PCR salió positiva. De las categoría CO-RADS 1, 5, 4 y 3, 278 CO-RADS 1 tuvieron PCR negativa y 28 prueba positiva, 601 CO-RADS 5 presentaron PCR positiva y 89 negativa, 45 CO-RADS 4 estimaron PCR positiva y 20 negativa, y 26 CO-RADS 3 obtuvieron PCR positiva y 72 negativa, demostrando tener una relación positiva significativa, con una p ≤ 0.001. Conclusiones: En nuestro estudio la clasificación de CO-RADS en los pacientes con alta sospecha de infección por COVID-19 tiene un alto valor predictivo positivo y el porcentaje de mortalidad obtenido, del 7%, es similar al reportado en otras publicaciones y en la OMS.

The KwaZulu-Natal province of South Africa has a varied topography, geology and climate and presents diverse habitats that support a rich and diverse flora. Aloes are well represented in KwaZulu-Natal, with four genera [Aloe L., Aloiampelos Klopper & Gideon F.Sm., Aloidendron (A.Berger) Klopper & Gideon F.Sm. and Aristaloe Boatwr. & J.C.Manning] and 49 taxa occurring in the province. Fourteen of these are endemic and eleven near-endemic to the province. A floristic treatment of the aloes of KwaZulu-Natal is presented in the form of a synoptic review. Included are an identification key to the aloes that occur naturally in the province, species-level distribution maps and accompanying images, so providing for the first time, an atlas of aloe occurrence in this part of the subcontinent.

Background: Many instructors transitioned their courses from face-to-face environments to computer-mediated learning environments (CMLEs) following the onset of the coronavirus disease 2019 (COVID-19) pandemic. However, little was known about how teleconferencing platforms and their corresponding functions affect student learning when the COVID-19 pandemic began. Objectives: The aim of this study was to provide more clarity on the conditions through which online teleconferencing platforms influence student achievement. More specifically, this study investigated how displaying lecture-relevant and lecture-irrelevant messages in a chat box during a video lecture delivered via the Zoom teleconferencing platform affected student learning and note taking. Methods: Participants viewed the video lecture either with (relevant or irrelevant) or without messages appearing in the chat box of the Zoom window. Participants completed a learning test immediately following the lecture. Results and Conclusions: No difference regarding student achievement was observed between the three groups. However, results revealed that students in the relevant-lecture messages group reported a higher extraneous cognitive load than the other groups even if they reported positive attitudes about the messages appearing on the chat box. Students in the lecture-relevant group also recorded more notes during the lecture compared to the two other groups, but this result did not reach significance. This study extends previous research that investigated how messaging influences learning in classroom settings. Findings suggest that allowing relevant discussions is not the best strategy to promote learning in CMLEs as this information seems to compete with the other relevant information being presented during the ongoing lecture.

A hydrological basin is established as a geographic frame to officially determine surface water availability and is basic to confer or deny water rights. In Mexico, the legal definition of a hydrological basin is confusing and inconsistent with the official basin delineation published by the authority. This situation is demonstrated through the analysis of eight study cases located in Hydrological Region 10 Sinaloa. A proposal to define the legal term of hydrological basin, ensuring its consistency with official delineation of hydrological basins is presented. Geographic analysis was performed using QGIS software, by using official sources of Mexico and worldwide data bases. By law, in Mexico a water parting is defined as a borderline of maximum elevation. Nevertheless, the legal definition fails to explain hydrologic basin official boundaries where the basin limit is the location of a hydrometric station. Besides, the presence of this equipment does not mean that a waterbody exists in a hydrological basin, or that the delimited basin is an autonomous differentiated unit, as it is required by the legal definition. Other inconsistencies are presented dealing with the presence of inland water bodies as watershed limits and with groups of independent watersheds incongruously considered as a single basin. An amendment is proposed to harmonize this situation, with a minimum of changes in policy documents. The method proposed can be useful to analyze similar situations in other countries where discrepancies between the legal and official definitions of watershed delineation are also observed, or in countries where no official watershed definition has been established.

Forest restoration is necessary for maintaining healthy watersheds and the ecological spatial networks that provide environmental goods and services. Consideration of the dollar value of these provided benefits in restoration planning is essential to the efficient use of limited resources available to project implementation. Nonmarket valuation is a methodology of economics commonly used to estimate monetary values for environmental goods and services that are not typically bought or sold in a traditional market. Valuation studies are prolific within the restoration literature; however, the use of nonmarket values as decision support is not well represented. We introduce a method using Geographic Information Systems (GIS) to spatially analyze the results from a nonmarket valuation study that estimated dollar values for the attributes of forest restoration characteristic of a semi-arid watershed in the Southwest United States. Map layers were created for the five attributes valued by the study and represent areas in the watershed that are designated as critical habitats, determined to influence surface water quality, prone to high-severity wildfire, representative of culturally significant areas, and contribute to aquifer recharge. A series of overlay analyses were performed to create a composite benefit map that spatially displays nonmarket values throughout the watershed. The per acre benefit values range from USD 0 to USD 104 where all five attributes are present.

ABSTRACT: Objective: To present a rare case of parathyromatosis. Methods: We present the clinical, laboratory, and imaging findings, along with a review of the literature. Results: A 33-year-old man with a history of right upper parathyroid adenoma removal 5 years prior due to hyperparathyroidism was admitted for severe hypercalcemia (15.6 mg/dL; normal, 8.5 to 10.5 mg/dL) with elevated plasma parathyroid hormone (PTH) (882 pg/mL; normal, 15 to 65 pg/mL). Ultrasound, computed tomography (CT), sestamibi, and positron emission tomography scans were unremarkable; however, a four-dimensional CT (4DCT) of the neck showed an area of increased signal enhancement and hypervascularity without discrete nodule in the posterior right thyroid region. The patient underwent parathyroid surgical exploration with right hemithyroidectomy and compartment neck dissection to remove the affected tissue. PTH levels dropped to 208 pg/mL postoperatively; calcium decreased but remained elevated at 12.7 mg/dL. Pathology revealed the presence of several small nodular foci of atypical hyperplastic parathyroid tissue in the right thyroid and soft tissue in the left central neck compartment consistent with parathyromatosis. Conclusion: This case report represents the first-time use of 4DCT to localize parathyromatosis. Parathyromatosis is a rare but problematic cause of recurrent hyperparathyroidism. Ultrasound and 4DCT may represent the best imaging modalities for identification and perioperative management to remove all affected tissue without reseeding.

The principal aim of this study was to establish biogeographical patterns in the legume flora of southern Africa so as to facilitate the selection of species with agricultural potential. Plant collection data from the National Herbarium, South Africa, were analysed to establish the diversity and areas covered by legumes (Leguminosae/Fabaceae) indigenous to South Africa, Lesotho and Swaziland. A total of 27,322 records from 1,619 quarter degree grid cells, representing 1,580 species, 122 genera and 24 tribes were included in the analyses. Agglomerative hierarchical clustering was applied to the presence or absence of legume species in quarter degree grid cells, the resultant natural biogeographical regions (choria) being referred to as leguminochoria. The description of the 16 uniquely formed leguminochoria focuses on defining the associated bioregions and biomes, as well as on the key climate and soil properties. Legume species with a high occurrence in a leguminochorion are listed as key species. The dominant growth form of key species, species richness and range within each leguminochorion is discussed. Floristic links between the leguminochoria are established, by examining and comparing key species common to clusters, using a vegetation classification program. Soil pH and mean annual minimum temperature were found to be the main drivers for distinguishing among legume assemblages. This is the first time that distribution data for legumes has been used to identify biogeographical areas covered by leguminochoria on the subcontinent. One potential application of the results of this study is to assist in the selection of legumes for pasture breeding and soil conservation programs, especially in arid and semi-arid environments.

Ekebergia capensis is a medium-sized to large evergreen to deciduous tree ranging from southern Africa to Ethiopia. Two morphologically-distinct variants of E. capensis, southern and northern, may be recognized in southern Africa. Despite its wide distribution range there appear to be no published reports on the secretory structures occurring on the leaves. In very young leaves, colleters on the petiolules, adjacent portions of the rachis and the midrib of the adaxial leaflet surfaces, secrete fluid which at least partly covers these developing areas. This is the first record of colleters in Meliaceae. In addition, several extrafloral nectaries (EFNs) are found in variable positions on the abaxial side of the leaflets. No stomata are associated with the EFNs. The glandular tissue of active EFNs is surrounded by druse crystals of calcium oxalate and consists of secretory cells some of whose walls are separated by “strands” of amorphous lipophilic material, especially in a radial orientation. EFNs on developing leaves are inconspicuous but with time, frequently become more easily visible due to the accumulation of pinkish/reddish anthocyanins. Even on senescent leaves, shed in autumn, large droplets of nectar are frequently visible on the EFNs. The secretory tissue originates from protoderm and ground tissues. Slight differences in abundance, size, shape, position and structure exist between the EFNs of the southern and northern forms. Varying proportions of glucose, fructose and sucrose were detected in the rather viscous nectar with the most abundant sugar usually being fructose. Ants were only rarely observed feeding on the nectar. This finding is in conflict with the generally accepted idea that EFNs provide food for ants which in turn protect the plant from herbivores. More detailed studies of the chemistry of the nectar, which is relatively copious, may provide clues as to the function.

Caesalpinia pulcherrima (Caesalpiniaceae) is an ornamental plant with several ethnomedicinal uses. The present study was designed to investigate the brine shrimp cytotoxicity and insecticidal activity of oil obtained from C. pulcherrima root. The powdered root was extracted with methanol and then defatted with petroleum ether (40-60oC) to obtain a viscous oil. The oil was investigated for its brine shrimp cytotoxicity and insecticidal activity in vitro. The chemical constituents were identified by Gas chromatography-Mass spectrometry. The oil showed significant lethal effect against Artemia salina (Brine shrimp) with LC50 of 23.85 μg/mL and mild insecticidal activity against Tribolium castaneum and Callosbruchus analis with percentage mortality of 20% and 40% respectively at 1 mg/cm2. GC-MS analysis identified 37 compounds mainly steroids, terpenoids and fatty acids. Keywords: Caesalpinia pulcherrima, chemical constituents, cytotoxicity, insecticidal activity.

River basin delineation can be inappropriate to determine surface water availability in a country, even if it is established by its water authority. This is because the effect of agricultural and urban infrastructure in runoff direction is ignored, and the anthropogenic changes in hydrography and topography features distort the runoff. This situation is really important because water rights are granted based on volumes that are not physically accessible. The existence of this problem is demonstrated through a case of study: the Culiacan River Basin in Mexico. To overcome such a situation, this study poses criteria to revise official river basin configurations and to delineate new river basins based on digital elevation models, vector files of agricultural infrastructure, and extensive field verification. Significant differences were noticed in surface water availability calculated under distinct river basin delineations.

Many college students prefer to type their lecture notes rather than write them by hand. As a result, the number of experimental and quasi-experimental studies comparing these two note-taking mediums has flourished over the past decade. The present meta-analytic research sought to uncover trends in the existing studies comparing achievement and note-taking outcomes among college students. Results from 24 separate studies across 21 articles revealed that taking and reviewing handwritten notes leads to higher achievement (Hedges' g = 0.248; p < 0.001), even though typing notes benefits note-taking volume (Hedges' g = 0.919; p < 0.001), among college students. Furthermore, our binomial effect size display shows that taking handwritten lecture notes is expected to produce higher course grades than typing notes among college students. We conclude that handwritten notes are more useful for studying and committing to memory than typed notes, ultimately contributing to higher achievement for college students.

We recorded the hyper-Raman spectra resulting from the interaction of a near-infrared (near-IR) picosecond pulse and a terahertz (THz) ultrashort pulse at the surface of a (111) silicon sample. A simple model is proposed to analyze the evolution of the hyper-Raman spectra vs the time delay between the near-IR and THz pulses. It links the hyper-Raman spectra to the multi-phonon absorption in silicon. This approach makes it possible to demonstrate that, during carrier generation by the near-IR pulse, the two-phonon and three-phonon absorption bands are enhanced in modes involving optical phonons. This process results from the very rapid and strong population of the optical phonons induced by the photo-generated hot carriers. It occurs over a few hundreds of femtoseconds and lasts throughout the duration of the near-IR pulse. [ABSTRACT FROM AUTHOR]

Background: Helictotrichon (excluding Amphibromus, Avenula, Helictochloa and Tricholemma), a genus of temperate C3 grasses, is represented by 14 species in southern Africa. Members of the genus are difficult to identify at species level on the basis of macromorphology alone. Objectives: The primary objective of this study was to investigate the usefulness of the micromorphology of the lemma surface for differentiating amongst the southern African members of Helictotrichon. Method: Lemma surfaces were studied with scanning electron microscopy (SEM). Lemmas were obtained from herbarium specimens housed in the National Herbarium, Pretoria (PRE). These were mounted on aluminium stubs using double-sided adhesive tape, sputter-coated with gold, and photographs were taken using a J840 scanning electron microscope. Results: Based on whether the lemma surface is smooth, papillate, scaberulous, scabrid or a combination of these, five groups of species are distinguished. All species, except Helictotrichon barbatum which has a smooth lemma surface, have small prickles (scaberulous). Helictotrichon leoninum, Helictotrichon quinquesetum and Helictotrichon rogerellisii have only small prickles, whilst Helictotrichon dodii, Helictotrichon hirtulum, Helictotrichon namaquense and Helictotrichon roggeveldense have, in addition, medium to large prickles (scabrid). Helictotrichon capense, Helictotrichon longifolium, Helictotrichon longum and Helictotrichon turgidulum have a combination of small prickles and papillae whilst Helictotrichon galpinii and Helictotrichon natalense have a combination of all three. A key to the groups and photos of the different types of surfaces are provided. Conclusion: The micromorphology of the lemma surface was shown to be of considerable taxonomic significance and to be extremely useful for differentiating amongst species.

Oberholzeria etendekaensis, a succulent biennial or short-lived perennial shrublet is described as a new species, and a new monotypic genus. Discovered in 2012, it is a rare species known only from a single locality in the Kaokoveld Centre of Plant Endemism, north-western Namibia. Phylogenetic analyses of molecular sequence data from the plastid matK gene resolves Oberholzeria as the sister group to the Genisteae clade while data from the nuclear rDNA ITS region showed that it is sister to a clade comprising both the Crotalarieae and Genisteae clades. Morphological characters diagnostic of the new genus include: 1) succulent stems with woody remains; 2) pinnately trifoliolate, fleshy leaves; 3) monadelphous stamens in a sheath that is fused above; 4) dimorphic anthers with five long, basifixed anthers alternating with five short, dorsifixed anthers, and 5) pendent, membranous, one-seeded, laterally flattened, slightly inflated but indehiscent fruits.

Current sequencing methods produce large amounts of data, but genome assemblies based on these data are often woefully incomplete. These incomplete and error-filled assemblies result in many annotation errors, especially in the number of genes present in a genome. In this paper we investigate the magnitude of the problem, both in terms of total gene number and the number of copies of genes in specific families. To do this, we compare multiple draft assemblies against higher-quality versions of the same genomes, using several new assemblies of the chicken genome based on both traditional and next-generation sequencing technologies, as well as published draft assemblies of chimpanzee. We find that upwards of 40% of all gene families are inferred to have the wrong number of genes in draft assemblies, and that these incorrect assemblies both add and subtract genes. Using simulated genome assemblies of Drosophila melanogaster, we find that the major cause of increased gene numbers in draft genomes is the fragmentation of genes onto multiple individual contigs. Finally, we demonstrate the usefulness of RNA-Seq in improving the gene annotation of draft assemblies, largely by connecting genes that have been fragmented in the assembly process.

A hallmark of visual rhabdomeric photoreceptors is the expression of a rhabdomeric opsin and uniquely associated phototransduction molecules, which are incorporated into a specialized expanded apical membrane, the rhabdomere. Given the extensive utilization of rhabdomeric photoreceptors in the eyes of protostomes, here we address whether a common transcriptional mechanism exists for the differentiation of rhabdomeric photoreceptors. In Drosophila, the transcription factors Pph13 and Orthodenticle (Otd) direct both aspects of differentiation: rhabdomeric opsin transcription and rhabdomere morphogenesis. We demonstrate that the orthologs of both proteins are expressed in the visual systems of the distantly related arthropod species Tribolium castaneum and Daphnia magna and that their functional roles are similar in these species. In particular, we establish that the Pph13 homologs have the ability to bind a subset of Rhodopsin core sequence I sites and that these sites are present in key phototransduction genes of both Tribolium and Daphnia. Furthermore, Pph13 and Otd orthologs are capable of executing deeply conserved functions of photoreceptor differentiation as evidenced by the ability to rescue their respective Drosophila mutant phenotypes. Pph13 homologs are equivalent in their ability to direct both rhabdomere morphogenesis and opsin expression within Drosophila, whereas Otd paralogs demonstrate differential abilities to regulate photoreceptor differentiation. Finally, loss-of-function analyses in Tribolium confirm the conserved requirement of Pph13 and Otd in regulating both rhabdomeric opsin transcription and rhabdomere morphogenesis. Taken together, our data identify components of a regulatory framework for rhabdomeric photoreceptor differentiation in Pancrustaceans, providing a foundation for defining ancestral regulatory modules of rhabdomeric photoreceptor differentiation.

Secondary pollen presentation is a well-known phenomenon in the Rubiaceae with particularly conspicuous pollen presenters occurring in the tribe Vanguerieae. These knob-like structures are formed by a modification of the upper portion of the style and stigma, together known as the stylar head complex. In the flower bud and shortly before anthesis, the anthers surrounding the stylar head complex dehisce and release pollen grains which adhere to the pollen presenter. The epidermal cells of the pollen presenter facing the anthers are radially elongated with a characteristic wall thickening encircling the anticlinal walls of each cell towards the distal end. These cells were studied in the pollen presenter of Vangueria infausta using electron and light microscopy in conjunction with histochemical tests and immunohistochemical methods. Other prominent thickenings of the cell wall were also observed on the distal and proximal walls. All these thickenings were found to be rich in pectin and possibly xyloglucan. The terms "thickenings of Igersheim" and "bands of Igersheim" are proposed to refer, respectively, to these wall structures in general and those encircling the anticlinal walls of each cell near the distal end. The epidermal cells have an intricate ultrastructure with an abundance of organelles, including smooth and rough endoplasmic reticulum, Golgi apparatus, mitochondria and secretory vesicles. This indicates that these cells are likely to have an active physiological role. The pollen grains possess prominent protruding onci and observations were made on their structure and development. Walls of the protruding onci are also rich in pectin. Pectins are hydrophilic and known to be involved in the dehydration and rehydration of pollen grains. We hypothesise that the thickenings of Igersheim, as well as the protruding onci of the pollen grains, are functionally associated and part of the adaptive syndrome of secondary pollen presentation, at least in the Vanguerieae.

Many college students believe that typing lecture notes on computers produces better notes and higher achievement than handwritten lecture notes on paper. The few studies investigating computer versus longhand note taking yielded mixed note-taking and achievement findings. The present study investigated computer versus longhand note taking but permitted note takers to revise or recopy notes during pauses interspersed throughout the lecture. Moreover, the present study analyzed notes recorded while a lecture was ongoing and following revision pauses to determine if lecture ideas and images were recorded completely or partially. Findings did not support the belief that computers aid note taking and achievement and, instead, favored longhand note taking and revision. Computer and longhand note takers recorded a comparable number of complete and partial ideas in notes while the lecture was ongoing, but longhand note takers recorded more lecture images. Among note revisers, longhand note takers added three-times-as-many complete ideas to their notes during revision as computer note takers--an important finding because note completeness predicted achievement. Achievement results showed that longhand note takers who revised notes scored more than half a letter grade higher on a lecture posttest than computer note takers who revised notes. Present findings suggest that college instructors should provide students with revision pauses to improve note taking and achievement and encourage students to record and revise notes using the longhand method. Finally, regarding the computer versus longhand note-taking debate, the need to investigate further the interplay between note-taking medium and lesson material is discussed.

Domatia are small structures on the lower surface of a leaf, usually taking the form of cavities, pouches, domes with an opening, or hairs (or a combination of these), and located in the axils between the main veins. They are found in many dicotyledons including certain members of the Rubiaceae. As part of an ongoing study of selected southern African members of the tribe Vanguerieae of this family, their structure in transverse section was investigated. In some taxa, such as Plectroniella armata, light microscopic (LM) observations revealed large numbers of stomata in the domatia as well as a number of channel-like structures extending across the cuticle toward the cavity of the domatia. The cuticle of the epidermis lining the domatia also appeared thicker than in other parts of the leaves. The epidermis in P. armata was also examined using transmission electron microscopy (TEM). Domatia have been shown to house mainly mites, many of which are predatory or fungivorous, in a symbiotic (mutualistic) relationship with the plant. To date, much research has focussed on the role of domatia in providing shelter for various organisms, their eggs and their young. However, the TEM study revealed the apparent "channels" and thick cuticle seen under LM to be electron dense non-cellulosic branching fibrils within pronounced, often closely spaced cuticular folds. The functional significance of these fibrils and folds requires further investigation. Folding of cell walls and membranes at ultrastructural level is usually functionally associated with an increased surface area to facilitate active exchange of compounds/metabolites. This may indicate that translocation of substances and/or other forms of communication is possible between the domatium and its inhabitants. This therefore suggests a far more active role for the leaf in the symbiotic relationship than was previously thought. More work is required to test such a possibility.

The distributions of naturalised alien plant species that have invaded natural or semi-natural habitat are often geographically restricted by the environmental conditions in their new range, implying that alien species with similar environmental requirements and tolerances may form assemblages and characterise particular areas. The aim of this study was to use objective numerical techniques to reveal any possible alien phytogeographic regions (i.e. geographic areas with characteristic alien plant assemblages) in southern Africa. Quarter degree resolution presence records of naturalised alien plant species of South Africa, Lesotho, Swaziland, Namibia and Botswana were analysed through a divisive hierarchical classification technique, and the output was plotted on maps for further interpretation. The analyses revealed two main alien phytogeographic regions that could be subdivided into eight lower level phytogeographic regions. Along with knowledge of the environmental requirements of the characteristic species and supported by further statistical analyses, we hypothesised on the main drivers of alien phytogeographic regions, and suggest that environmental features such as climate and associated biomes were most important, followed by human activities that modify climatic and vegetation features, such as irrigation and agriculture. Most of the characteristic species are not currently well-known as invasive plant species, but many may have potential to become troublesome in the future. Considering the possibility of biotic homogenization, these findings have implications for predicting the characteristics of the plant assemblages of the future. However, the relatively low quality of the dataset necessitates further more in-depth studies with improved data before the findings could be directly beneficial for management.

We recently showed that hypoxia-inducible factor 1 (HIF-1) plays a crucial role in the pro-allergic functions of human basophils by transcriptional control of energy metabolism via glycolysis as well as directly triggering expression of the angiogenic cytokine vascular endothelium growth factor (VEGF). Here, we investigated HIF-1 involvement in controlling the synthesis of angiogenic and inflammatory cytokines from various human effector cells stimulated by IgE-dependent or innate immune triggers. Purified primary human basophils, LAD2 human mast cells and THP-1 human myeloid cells were used for investigations of FcεRI and Toll-like receptor (TLR) ligand-induced responses. In contrast to basophils, LAD2 mast cells expressed background levels of HIF-1α, which was largely independent of the effects of stem cell factor (SCF). Both mast cells and basophils expressed TLR2 and 4, albeit weakly compared to THP-1 cells. Cytokine production in mast cells following TLR ligand stimulation was markedly reduced by HIF-1α knockdown in LAD2 mast cells. In contrast, although HIF-1 is involved in IgE-mediated IL-4 secretion from basophils, it is not clearly induced by peptidoglycan (PGN). HIF-1α accumulation is critical for sustaining human allergic effector cell survival and function. This transcription complex facilitates generation of both pro-angiogenic and inflammatory cytokines in mast cells but has a differential role in basophil stimulation comparing IgE-dependent triggering with innate immune stimuli.

We examined college instructors' perceptions of the behaviors and contextual factors that allow them to initiate and maintain rapport with their students. Phenomenological interviews with 21 college instructors indicated that instructors rely on different strategies and contextual factors to initiate and to maintain rapport with students across the semester. At the beginning of the semester, these instructors rely on a variety of connecting, common grounding, and information sharing behaviors and leverage baked-in rapport to cultivate a sense of rapport from their students. After rapport has been initiated, these instructors place more emphasis on attentive and courteous behaviors, while continuing to engage in connecting behaviors. Furthermore, these instructors identified personalized instruction and tactful responses to delicate situations as essential for maintaining a strong sense of rapport across the semester. Findings from the present study provide college instructors with a framework for initiating and maintaining rapport with students in their classrooms.

The present study investigated how course policies and enforcement strategies designed to curb classroom digital distraction affect undergraduates' perceptions of student-instructor rapport. Data gathered from online surveys completed by undergraduates at four United States universities revealed that student perceptions of rapport can be influenced by digital distraction prevention. Participants endorsed course technology policies that are developed in collaboration between students and instructors and that are targeted at curbing the use of digital devices for social, rather than educational, purposes. Findings indicate that such policies can improve student buy-in and improve student perceptions of rapport. Although participants identified confrontational enforcement strategies (e.g., calling students out, grade reductions, phone confiscation) as most effective for reducing the amount of digital distraction during class when policies are violated, these strategies were also identified as being most harmful to their perceptions of rapport with instructors. Despite regularly using devices for off-task purposes during class, most participants are not worried about getting caught because they do not believe their instructors are particularly concerned about the amount of ongoing digital distraction in the classroom. Recommendations for addressing student digital distraction while protecting the quality of student-instructor rapport are provided through the lens of self-determination theory.

Objectives: Although prior research has uncovered shifts in computer science (CS) students' implicit beliefs about the nature of their intelligence across time, little research has investigated the factors contributing to these changes. To address this gap, two studies were conducted in which the relationship between ineffective self-regulation of learning experiences and CS students' implicit intelligence beliefs at different times during the semester was assessed. Participants: Participants for Studies 1 (n = 536) and 2 (n = 222) were undergraduate students enrolled in introductory- and upper-level CS courses at a large, public, Midwestern university. Race-ethnicity information was not collected due to IRB concerns about possible secondary identification of participants from underrepresented groups. Study Method: Participants completed a condensed version of the Implicit Theories of Intelligence Scale [16, 54] and the Lack of Regulation Scale from the Student Perceptions of Classroom Knowledge Building scale [51, 53] at the beginning (Studies 1 and 2), middle (Study 2), and end (Studies 1 and 2) of semester-long undergraduate CS courses. Survey responses were analyzed using path analyses to investigate how students' lack of regulation experiences throughout the semester predicted their implicit intelligence beliefs at the beginning (Study 2) and end (Studies 1 and 2) of the semester. Findings: Results from Study 1 indicate that undergraduate CS students come to more strongly believe that their intelligence is a fixed, unchanging entity from the beginning until the end of the semester. Moreover, participants' responses to the lack of regulation scale were predictive of their implicit intelligence beliefs at the end of the semester. Results from Study 2 indicate that ineffective self-regulation experiences early in the semester enhance CS students' belief in the unchanging nature of intelligence (i.e., during the first half of the semester). Taken altogether, these findings provide evidence that self-regulation experiences influence students' beliefs about the malleability of intelligence. Conclusions: Findings align with Bandura's [4] contention that students' behaviors and experiences influence their values and beliefs. Students who experienced poor self-regulated learning came to view intelligence as more of a fixed, unalterable entity than their more successfully self-regulated peers. Findings suggest that CS instructors can positively affect student motivation and engagement by embedding self-regulated learning strategy instruction into their courses and helping CS students adopt an incremental-oriented (e.g., growth-oriented) belief system about their intellectual abilities.

Stem cell factor (SCF) is a hematopoietic growth factor that exerts its activity by signalling through the tyrosine kinase receptor known as Kit or CD117. SCF-Kit signalling is crucial for the survival, proliferation and differentiation of hematopoietic cells of myeloid lineage. Furthermore, since myeloid leukaemia cells express the Kit receptor, SCF may play an important role in myeloid leukaemia progression too. However, the mechanisms of this pathophysiological effect remain unclear. Recent evidence shows that SCF triggers accumulation of the inducible alpha subunit of hypoxia-inducible factor 1 (HIF-1) in hematopoietic cells--a transcription complex that plays a pivotal role in cellular adaptation to low oxygen availability. However, it is unknown how SCF impacts on HIF-1α accumulation in human myeloid leukaemia and mast cells. Here we show that SCF induces HIF-1α accumulation in THP-1 human myeloid leukaemia cells but not in LAD2 mast cells. We demonstrated that LAD2 cells have a more robust glutathione (GSH)-dependent antioxidative system compared to THP-1 cells and are therefore protected against the actions of ROS generated in an SCF-dependent manner. BSO-induced GSH depletion led to a significant decrease in HIF-1α prolyl hydroxylase (PHD) activity in THP-1 cells and to near attenuation of it in LAD2 cells. In THP-1 cells, SCF-induced HIF-1α accumulation is controlled via ERK, PI3 kinase/PKC-δ/mTOR-dependent and to a certain extent by redox-dependent mechanisms. These results demonstrate for the first time an important cross-talk of signalling pathways associated with HIF-1 activation--an important stage of the myeloid leukaemia cell life cycle.

This study updates and extends prior work on institutional and individual productivity in educational psychology journals ("Cognition and Instruction," "Contemporary Educational Psychology," "Educational Psychologist," "Educational Psychology Review," "Journal of Educational Psychology") from 2015 to 2021. As in previous studies, the University of Maryland, College Park, was the top-producing institution. Several universities (e.g., University of Tübingen) emerged as highly productive compared to previous time periods. Using two approaches to measure individual productivity, we found that Richard Mayer, Ulrich Trautwein, Fred Paas, Patricia Alexander, and Logan Fiorella claimed the top spots. We also identified productive early career scholars and, for some, recognized connections to productive doctoral advisors. Overall, compared to prior years, authors of educational psychology journal articles were increasingly working from non-US institutions and in larger teams (higher mean number of authors per article). A discussion of these trends and future directions for research are included.

This paper presents the unscented transform (UT) applied to uncertainty modeling of manufacturing tolerances at the design stage of microwave passive devices. The process combines the UT with electromagnetic simulations and assumes that the numerical sources of error are negligible in comparison to the imperfections due to the manufacturing process. The technique was validated with the simulation, construction, and test of several sets of identical microstrip filters with very good results. Although the combination of UT and electromagnetic simulators was presented for microstrip filters, it can also be used for different types of microwave devices.