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To eliminate the negative effect of soil contamination with heavy metals on plant growth and crop yield, different methods and techniques are the subject of discussion and study. In this study, we aimed to evaluate the effect of secondary pulp and paper-mill sludge application to soil on the response of the main physiological processes such as the growth, photosynthesis, and respiration of lettuce (Lactuca sativa L.) plants to soil contamination with Pb. For the pot experiment, Pb was added to sandy loam soil at concentrations of 0, 50, and 250 mg Pb(NO3)2 per kg of the soil, and secondary sludge was added to a 0, 20, or 40% sludge solution during each plant watering. The Pb-mediated change in plant biomass allocation, decrease in the photosynthetic rate, increase in leaf respiration rate, and the degree of light inhibition of respiration were closely associated with increases in both root and shoot Pb content. For the Pb-free soil condition, secondary sludge application contributed to the allocation of plant biomass towards a greater accumulation in the shoots than in the roots. Although stomatal opening was not affected by either Pb or sludge, sludge application increased photosynthetic CO2 assimilation regardless of soil Pb content, which was associated with an increase in the electron-transport rate and carboxylase activity of Rubisco. Soil contamination with Pb significantly increased the ratio of respiration to photosynthesis, reflecting a shift in the carbon balance toward carbon losses in the leaves, but sludge application modified the coupling between the processes with a decrease in the proportion of respiratory carbon losses. The sludge-mediated recovery of the physiological processes of L. sativa reflected an increase in plant tolerance to soil contamination with heavy metals, the formation of which is associated with plant and soil adjustments initiated by secondary sludge application.

The paper mulberry is a commonly found tree species with a long history of cultivation. It also serves as a crucial case study for understanding how woody plants adapt to low temperatures. Under cold treatment, we observed a substantial number of alternative splicing (AS) genes, showcasing the intricate landscape of AS events. We have detected all seven types of AS events, with the alternative 3′ splice site (A3) having the most. We observed that many genes that underwent differential AS were significantly enriched in starch and sucrose metabolism and circadian rhythm pathways. Moreover, a considerable proportion of differentially spliced genes (DSGs) also showed differential expression, with 20.38% and 25.65% under 12 h and 24 h cold treatments, respectively. This suggests a coordinated regulation between gene AS and expression, playing a pivotal role in the paper mulberry’s adaptation to cold stress. We further investigated the regulatory mechanisms of AS, identifying 41 serine/arginine-rich (SR) splicing factors, among which 11 showed differential expression under cold treatment, while 29 underwent alternative splicing. Additionally, genes undergoing AS displayed significantly higher DNA methylation levels under cold stress, while normal splicing (non-AS) genes exhibited relatively lower methylation levels. These findings suggest that methylation may play an important role in governing gene AS. Finally, our research will provide useful information on the role of AS in the cold acclimation tolerance of the paper mulberry.

This laboratory exercise affords students a hands-on experience learning about traditional dyes, fiber strength, and paper making. It is economical, simple to prepare, provides satisfactory results, and is student friendly. Dyes were extracted from plant leaves, stems, roots, and fruits. Hard-boiled eggs were place in the dyes for 15 minutes to determine what color each dye would produce. Colors of the eggs differed from the colors of the dye solutions. Fibers were procured from different materials (cotton, jute, hemp, etc.). Filaments were removed from the twine and a stress test was used to determine the strength:weight for each fiber type. Twine from each fiber type was used to make rope using the rope maker from the Boy Scout's Pioneering merit badge pamphlet (1993). Paper was made from recycled fibers suspended in water. A homemade deckle was used to collect and press the fibers to make a sheet of paper. Students found the exercise interesting and stimulating. (Contains 1 table.)

Abstract Background Broussonetia papyrifera (L.) L’Hér. ex Vent. has the characteristics of strong stress resistance, high crude protein content, and pruning tolerance. It is an ecological, economic, and medicinal plant. Polyploid plants usually perform better than their corresponding diploid plants in terms of nutrients, active substances, and stress resistance. Results In this study, the leaves, calli, and seeds of diploid B. papyrifera were used for tetraploid induction by colchicine. The induction effect of colchicine on B. papyrifera was summarized through the early morphology, chromosome count and flow cytometry. It was concluded that the best induction effect (18.6%) was obtained when the leaves of B. papyrifera were treated in liquid MS (Murashige and Skoog) medium containing 450 mg·L-1 colchicine for 3 d. The comparative analysis of the growth characteristics of diploid and tetraploid B. papyrifera showed that tetraploid B. papyrifera has larger ground diameter, larger stomata, thicker palisade tissue and thicker sponge tissue than diploid B. papyrifera. In addition, the measurement of photosynthetic features also showed that tetraploids had higher chlorophyll content and higher photosynthetic rates. Conclusion This study showed that tetraploid B. papyrifera could be obtained by treating leaves, callus and seeds with liquid and solid colchicine, but the induction efficiency was different. Moreover, there were differences in stomata, leaf cell structure and photosynthetic features between tetraploid B. papyrifera and its corresponding diploid. The induced tetraploid B. papyrifera can provide a technical basis and breeding material for the creation of B. papyrifera germplasm resources in the future.

The separately stored type herbarium of the Herbarium Greuter in Palermo is comprised of 339 sheets, corresponding to 336 specimens pertaining to 328 different names. Material from the Mediterranean area, especially Greece, predominates, followed by that from the Caribbean (Cuba) and Australia. The list includes transcribed label data and links to the digital specimen images and to the protologue texts. A new type of terminology is introduced, with the terms “first-step holotype” and “second-step holotype” designating type categories parallel to the similar terms already in use for lectotypes, and the phrase “detailed here” is used as an equivalent to “designated here” in second-step typification.

The article discusses the importance of molecular plant sciences in sustaining food security in the face of global climate change. It emphasizes the need for interdisciplinary collaboration between plant science, physics, mathematics, and computer sciences to collect reliable information about plant biology and develop models that can predict interactions between genotype and environment. The article highlights the impact of abiotic and biotic stress on plants and the role of molecular biology in understanding stress resilience. It also discusses advancements in omics technologies, such as genomics and proteomics, for identifying genetic markers associated with stress tolerance. The article includes review papers on various topics, including plant responses to abiotic and biotic stress, methodology, and the detection and identification of specific plant species. Overall, the article provides valuable information for researchers in the field of molecular plant sciences and its applications in improving crop yields and food security. [Extracted from the article]

This paper provides evidence gathered from two suites of non-formal science activities that were intended to increase engagement in science by culturally diverse groups. Both studies involved the delivery of science activities that were designed, implemented and evaluated to show culturally contextualised science. The activities were run in two very different contexts (urban and very rural areas) and were designed to be of relevance to two distinctive cultural groups (those with links to South Asia, and those being educated through the medium of Gaelic, an indigenous minority language in Scotland), while also actively engaging with those beyond the target group. The link between language identity and culture was incorporated into the design of both sets of activities as well as the qualitative evaluation. The latter considers how the participants' assessment of the interventions, implemented by writing or drawing on a blank postcard, was designed to provide unstructured responses and explores what the resulting data revealed about the impact of the interventions. The findings suggest that the set of activities that most strongly engaged participants on the value of diversity in the creation of scientific knowledge, as well as increasing their focus on the consequences of scientific activity, were those that facilitated a more exploratory approach to the subject matter. By contrast, activities that had to be done according to a standard scientific protocol produced growth in subject-specific knowledge. The present paper explores the principles of the inclusive pedagogies that informed the design of the activities and discusses how these were operationalised in two very contrasting cultural contexts. The key finding was that presenting science as social practice, rather than as being socially neutral, is key to promoting engagement, along with the benefits of explicitly demonstrating the relevance of science to participants' daily lives.

This study aims at highlighting the collaborative activity of two high school students (age 14) in the cases of modeling the complex biological process of plant growth with two different tools: the "paper & pencil" concept mapping technique and the computer-supported educational environment "ModelsCreator". Students' shared activity in both cases is carried out in the presence of a facilitator providing technical as well as cognitive support when necessary. The objective of the study is to highlight the ways in which the collaborating students are engaged in the plant growth modeling activity in the two cases and also identify the activity's similar and different aspects in each one. Our analysis is carried out on two complementary axes, the first of which concerns the "process" of collaboratively creating a plant growth model with each different tool, while the second has to do with the students' conceptualizations of the biological aspect of the modeling task in each case. A two-level analytic tool for the modeling process has been derived within the theoretical framework of "activity theory" on the basis of the "OCAF" scheme for "basic modeling operations" and the scheme of Stratford et al. [Stratford, S. J., Krajcik, J., & Soloway, E. (1998). Secondary students' dynamic modeling processes: analyzing, reasoning about, synthesizing, and testing models of stream ecosystems. "Journal of Science Education and Technology," 7(3), 215-234.] for "higher-order modeling actions." According to our results, four major "modeling actions (analysis, synthesis, testing-interpreting, technical and cognitive support)" performed through a plethora of "modeling operations" define the steps of the modeling process in both cases, while specific qualitative differences can be actually identified. Finally, the students' conceptualizations of the biological aspect of the modeling task in the two-case activity is analyzed in regard with their capability of shifting reasoning between macro- and micro-levels, while educational implications are also discussed.

The 16th Congress of the Mediterranean Phytopathological Union (MPU2022) took place in Limassol, Cyprus from 4–8 April, 2022. Plant pathologists from the region and beyond celebrated the 60th anniversary of the Union and the 62 years of publication of Phytopathologia Mediterranea as a top level plant pathology journal. MPU2022 entitled “Safeguarding Mediterranean Plant Health” promoted dissemination of the latest scientific advances, and facilitated dialogue and collaboration between researchers interested in all aspects of Phytopathology. This conference also addressed wider perspectives in scientific fields not previously explored at MPU Congresses, including abiotic stresses, biopesticides, forest pathology, smart agriculture and gender equality in research, funding, teaching and professional development. Papers presented at the Congress included 83 oral presentations, including 15 keynote presentations from leading scientists, and 63 poster presentations, covering all areas of plant pathology and plant stress research, from 130 participants. Five special sessions in cutting edge subjects were organised. A special session was organised jointly with the Arab Society of Plant Protection. All these scientific contributions are part of this issue.

Abstract It is common practice in scientific journals to print genus and species names in italics. This is not only historical as species names were traditionally derived from Greek or Latin. Importantly, it also facilitates the rapid recognition of genus and species names when skimming through manuscripts. However, names above the genus level are not always italicized, except in some journals which have adopted this practice for all scientific names. Since scientific names treated under the various Codes of nomenclature are without exception treated as Latin, there is no reason why names above genus level should be handled differently, particularly as higher taxon names are becoming increasingly relevant in systematic and evolutionary studies and their italicization would aid the unambiguous recognition of formal scientific names distinguishing them from colloquial names. Several leading mycological and botanical journals have already adopted italics for names of all taxa regardless of rank over recent decades, as is the practice in the International Code of Nomenclature for algae, fungi, and plants, and we hereby recommend that this practice be taken up broadly in scientific journals and textbooks.

Plants is instituting the Best Paper Awards to recognize the outstanding papers published in the journal [...]

Bagging regulates the fruit microenvironment and improves the quality and market value of fruits. It is a safe and ecofriendly technique to protect fruits from insect/pest infestation and multiple biotic and abiotic stresses. In the current study, the influence of fruit bagging was evaluated on the development and quality of loquat fruits. Fruits from a healthy loquat orchard (Cv. Zaozhong No.6), located in Fujian, China, were enveloped in paper (T1), aluminum (T2), and aluminum–polyethylene bags (T3), while unbagged fruits were maintained as control (T0). In general, fruit bagging improved fruit quality in terms of fruit physiological and biochemical attributes and protected fruits from physical damage. In particular, aluminum–polyethylene bagging enhanced fruit weight, length, and width by 1.37-, 1.18-, and 1.13-fold, respectively. Loquat fruits bagged with paper bags exhibited the maximum soluble sugar and lowest titratable acid content. Fruits treated with paper and aluminum–ethylene bags showed twofold higher sugar–acid ratio as compared to control. Aluminum–polyethylene bagging caused 66.67%, 55.56%, and 33.33% reductions in skin burn, fruit rotting, and black spot of loquat. The fruits bagged in aluminum and aluminum–polyethylene did not show insect or bird damage, while unbagged fruits had 14.70% and 17.65% insect and bird damage, respectively. Overall, the results suggest that paper, aluminum, and aluminum–polyethylene bagging improved fruit health by 75%, 131%, and 144%, respectively, as compared to control. To delineate bagging type-dependent effects, principal component analysis was performed. Paper bagging was positively correlated with fruit firmness, rotting, soluble sugars, sugar–acid ratio, and proline content. Aluminum bagging was highly associated with improvements in titratable acids, cystine, and methionine. Aluminum–polyethylene bags were correlated with fruit weight, size, peel thickness, edible rate, and certain amino acids.

Drought is a key factor restricting plant survival, growth and development. The physiological parameters of plants are commonly used to determine the water status, in order to irrigate appropriately and save water. In this study, mulberry (Morus alba L.) and paper mulberry (Broussonetia papyrifera (L.) Vent.) seedlings were used as experimental materials, and four soil moisture treatments were set up for both plant species: 70–75% (CK: the control group, referred to as T0), 55–60% (T1: mild drought), 40–45% (T2: moderate drought), and 25–30% (T3: severe drought). The growth parameter of the plants was measured every two days from the onset of the treatment, the photosynthetic and electrophysiological parameters of the plants were measured every other week for a total of five times. The physiological responses and electrophysiological traits of leaves under different treatment levels were analyzed. The results showed that the photosynthetic and electrophysiological parameters could characterize the response of mulberry growth and development to soil water, and the growth and electrophysiological parameters could characterize the response of paper mulberry growth and development to soil water. Mild drought had no significant effects on the growth and development of mulberry and paper mulberry.

Plants is instituting the Best Paper Awards to recognize the outstanding papers published in the journal [...]

The characterization of plant compounds with pharmacological activity is a field of great relevance in research and development. As such, identification techniques with the goal of developing new drugs or even validating the bioactive properties of extracts must be explored in order to further expand the knowledge of plant extract composition. Most works in this field employ HPLC, when exploring non-structural and cell wall carbohydrates from Rhynchelytrum repens. Phenolic compounds were studied by classical chromatography techniques and UV-vis spectrophotometry, with C-glycosylated flavonoids being detected but with no further details regarding the chemical structure of these compounds. In this work we employ paper spray ionization mass spectrometry (PS-MS) for the evaluation of the chemical profile of R. repens methanol extract. Positive ionization mode identified 15 compounds, belonging to flavonoids, fatty acids, and other classes of compounds; negative mode ionization was able to identify 20 compounds comprising the classes of quinic acids, stilbenes and flavonoids. PS-MS proved effective for the evaluation of R. repens extracts, making it possible to identify a total of thirty-five compounds. The bioactive properties attributed to R. repens were confirmed by the identification and characterization of compounds identified by PS-MS.

The JK Paper industry located at Rayagada discharges biologically untreated effluent more than the permissible limit prescribed by Pollution Control Board, Odisha in to the environment. The industry is seriously polluting the surrounding aquatic and terrestrial environment. No detailed intensive study was carried out by previous workers on this industry earlier. The present study aims at finding out the impact of effluent on the flora at the contaminated site. The chemically treated effluent (TE) contained significant amount of mercury and cadmium. The TE has high BOD, COD, dissolved solids and suspended solids when compared to normal river water at the site of discharge. The TE deteriorated the natural water bodies changing the physico-chemical properties of natural river water. After meeting the river water the TE was diluted after 1 km distance from the meeting point of the river. Crop plants collected from the contaminated site showed higher level of residual Hg and Cd and significant depletion in pigment was observed. Plants collected from both the sides of the treated effluent canal showed significant amount residue mercury and cadmium in the plant leaves. The plants exposed to the TE, showed variation in chlorophyll and Phaeophytin pigment content when compared to their respective control values in all terrestrial plants collected from the contaminated site. In some plant leaves little increment in the pigment level was noted but the values were not significant. The changes observed in the plant pigment might be due to heavy metal accumulation. The presence of residual Hg and Cd in crop plants and plant leaves grazed by grazing animals after absorption, accumulation and enrichment may lead to a possible biological magnification, warrants attention. Proper biological treatment, treatment of effluent by modern methods and removal of heavy metals from the effluent before discharge by the industry is suggested. • Biological treatment of the effluent was not carried out by the industry & chemicals present in the effluent were significantly high.. • The water quality of the river water deteriorated due to the discharge of effluent of the paper mill. • Plants collected from the contaminated site showed significant accumulation of cadmium and mercury in leaf tissues • Significant depletion in pigment content of exposed plant leaves was noticed. • Depletion in plant pigment was due to accumulation of cadmium and mercury in plant tissues absorbed from the effluent. [ABSTRACT FROM AUTHOR]

During the COVID-19 pandemic, the existing Student Inquiry and Research program at Illinois Mathematics and Science Academy transitioned to a remote-only format. This paper describes the mentoring of 12 high school juniors and seniors in yearlong remote research projects involving plant biology and protein engineering. Working in groups of two or three, students read scientific articles and proposed experiments. An experienced researcher then carried out the experiments and gave the students the data. Students analyzed data, drew conclusions, and shared their results in an oral presentation and in a written paper. Despite the online-only format, all anonymously surveyed students agreed that the experience improved their confidence in both conducting and communicating scientific research, and 90% agreed that because of the experience, they are more likely to pursue a career in STEMM. These results are similar to those seen from in-person research experiences. Given the positive outcomes from this program, further development and use of remote research experiences may be beneficial, particularly for students who would not otherwise have access to any research opportunities. Remote learning technology thus enables existing resources of time and funding to be allocated differently to provide more students with authentic research experiences.

The First Joint Meeting on Soil and Plant System Sciences (SPSS 2019), titled “Natural and Human-Induced Impacts on the Critical Zone and Food Production”, aimed at integrating different scientific backgrounds and topics flowing into the Critical Zone, where chemical, biological, physical, and geological processes work together to support life on the Earth’s surface. The SPSS 2019 meeting gathered the thoughts and findings of scientists, professionals and individuals from different countries working in different research fields. This Special Issue comprises a selection of original works on the plant-related topics presented during this international meeting.

The results of studies on phenolic compounds occurence and variation in the two Aconitum species were reported in our previous paper (Szweykowski, Krzakowa, 1977a and b). A modified extraction method allowed us to get additional data on anthocyanin variation in flowers of the same species. In addition one albino plant of A. variegatum was also investigated in this respect.

The use of water-sensitive papers is an important tool for assessing the quality of pesticide application on crops, but manual analysis is laborious and time-consuming. Thus, this study aimed to evaluate and compare the results obtained from four software programs for spray droplet analysis in different scanned images of water-sensitive papers. After spraying, papers with four droplet deposition patterns (varying droplet spectra and densities) were analyzed manually and by means of the following computer programs: CIR, e-Sprinkle, DepositScan and Conta-Gotas. The diameter of the volume and number medians and the number of droplets per target area were studied. There is a strong correlation between the values measured using the different programs and the manual analysis, but there is a great difference between the numerical values measured for the same paper. Thus, it is not advisable to compare results obtained from different programs.

No abstract available.

In this opinion paper we investigate the effects of forest management on animal and plant biodiversity by comparing protected areas with intensively and extensively managed forests in Germany and in Romania. We want to know the extent to which differences in diversity of Romanian compared to German forests are based on management. The number of tree species was not different in protected and managed forests ranging between 1.8 and 2.6 species per plot in Germany and 1.3 and 4.0 in Romania. Also herbaceous species were independent of management, ranging between 13 species per plot in protected forests of Romania and 38 species per plot in German coniferous forest. Coarse woody debris was generally low, also in protected forests (14 to 39 m3 ha−1). The main difference between Romania and Germany was the volume of standing dead trees (9 to 28 m3 ha−1 for Romania), which resulted in larger numbers of forest relict saproxylic beetles independent of management. Large predators (wolves, bears and lynxes) are only found in regions with low human intervention. Thus, we identified a "cut and leave" type of management in Romania, in which clear-felling of forest are followed by long periods of no human intervention. Forests managed in the "cut and leave" mode contained the highest diversity, due to a natural succession of plant species and due to habitat continuity for animals. In Germany intensive management eliminates poorly formed tree individual and species of low market value during stand development. Forest protection does not ensure the maintenance of more light demanding key species of earlier stages of succession unless competition by shade-tolerant competitors is reduced through disturbances. We compare the economics of intensive and extensive management. The "cut and leave" mode delivers less wood to the wood market, but saves expenses of tending, thinning and administration. Thus the net income could be quite similar to intensive management at a higher level of biodiversity. Our analysis suggests that forest protection per se does not yet ensure the maintenance of species. Clear-felling followed by natural succession may even be superior to the protection of old growth forests, regarding biodiversity. Further research is needed to substantiate this hypothesis.

Over the past several decades, historians of science have come increasingly to focus on the role of so-called “paper technologies,” reorganizing and transforming information through the use of paper and pen, in the emergence of modern science. Taking as a case study an effort by administrators in the seventeenth-century German princely state of Saxe-Gotha to enlist foresters and herb-women to catalog the medicinal plants of the territory, this article analyzes the varied forms of paperwork produced in the process, including an extremely unusual table, and argues that the table represented an effort to produce a synoptic visualization, akin to but not identical to a map, of the location of the territory’s herbs. While this table may not have ultimately succeeded as a viable paper technology, due to problems of incommensurability, it demonstrates the role of administrative practices and state actors in experimenting with information about the natural world during the early modern period. [ABSTRACT FROM AUTHOR]

Worksheets are often used during field trips and utilize a learning cycle with three stages (exploration, concept introduction and concept application) to engage learners in the learning activities of observation and exploration. However, traditional paper worksheets do not provide multimedia and interactive presentations with physical objects, which made learners losing interaction with the physical context during field trips and failing to implement all the stages completely. This study designed an augmented reality worksheet with a three-stage learning cycle and applied it to learning about plants, specifically assisting learners in observing and classifying plants. A pretest-posttest quasi-experimental design was used to show the effect of learning when learners used augmented reality worksheets. Lag sequence analysis was used to identify learning behavioral patterns. The findings indicate that the learning effect of using augmented reality worksheets is much better than that of paper worksheets and improves the learners' interaction with plants.

The first overview is presented of the paper contents of Kew’s Economic Botany Collections (EBC). There are more than 350 specimens of paper representing nearly 50 plant families and more than a hundred genera. The dominant families numerically – and each for different reasons – are the Moraceae, Gramineae, Thymelaeaceae and Cyperaceae, examples from which are highlighted. Some emphasis is given to the historical context and geographical origin of papers, and to the people who collected or donated them. It is suggested that one focus of a future collecting strategy for the EBC should be the sorts of plant products, including papers, that are under threat due to losses of cultural diversity or biological diversity, or both. [ABSTRACT FROM AUTHOR]

• The study of plant–plant parasitism has experienced remarkable growth in the scientific literature. • Research on plant parasites has predominantly focused on ecological and physiological aspects in the last 20 yeras. • Aspects of evolution and host-parasite interactions needs further and deeper investigations. • We hope this special issue will serve as a catalyst for further advancements in the investigation of plant-plant parasitism. The study of plant–plant parasitism has experienced remarkable growth in the scientific literature, particularly over the past two decades. Hemi- and holoparasites, in particular, have been recognized as pivotal components within plant communities, capable of upscale effects to the ecosystem. Research on plant parasites has predominantly focused on ecological and physiological aspects of parasites and hosts, with a global distribution pattern. However, some fields remain relatively unexplored, and specific regions of Asia and the Global South (with exception of Australia and Brazil) have yet to receive comprehensive attention. Here, we introduce the theme on plant hemi- and holoparasites and explore publication trends on plant–plant parasitism over the past half-century, with a particular emphasis on papers published within the last two decades. We explore our findings to extend an invitation to researchers from diverse backgrounds and disciplines to contribute their expertise to a forthcoming Virtual Special Issue of Flora – Morphology, Distribution, Functional Ecology of Plants on "Plant Parasitism: Ecology, Evolution and Functional Aspects", with contributions expected from a wide range of topics related to ecology, physiology, morphology, systematics, and reproductive biology. We believe that this special issue will help in advancing our knowledge in plant-plant parasitism, fostering collaboration and facilitating the growth of this exciting area of research. [ABSTRACT FROM AUTHOR]

No abstract available.

Polistes ferreri Saussure, 1853 is a Neotropical paper wasp often found in anthropic environments. However, there is little information available on biological, ecological and behavioral interactions of this species under these environmental conditions. This study investigated the colony cycle, foundation strategy and nesting biology of this species. From March of 2000 to February of 2004, several colonies were studied in the municipal district of Juiz de Fora, in southeastern Brazil. The colony cycle events of P. ferreri are concentrated in specific periods of the year. The colonies are established principally by association of females, the latter is the foundation strategy that confers the greatest success. Nidification on manmade substrates seems common for the species. The peduncle of the nest is increased in width to support the weight of colony members. Likewise, cells are increased in height, in accordance with the size of the layers of meconium, allowing accommodation of the immature. It is suggested that, at least for post-emergent colonies of P. ferreri, the cost of nest construction is not a factor limiting the development of the colonies. Finally, the results also support the idea that the reuse of cells is an advantageous strategy because it saves costs related to the construction of new cells.Polistes ferreri Saussure, 1853 es una avispa de papel neotropical encontrada a menudo en ambientes antrópicos. Sin embargo, hay poca información disponible sobre las interacciones biológicas, ecológicas y de comportamiento de esta especie en estas condiciones ambientales. Este estudio investigó el ciclo de la colonia, la estrategia de fundación y la biología de anidación de esta especie. Desde marzo de 2000 a febrero de 2004, varias colonias fueron estudiadas en el municipio de Juiz de Fora, en el sureste de Brasil. Los eventos del ciclo de la colonia de P. ferreri se concentran en determinados períodos del año. Las colonias se establecen, principalmente, por asociación de hembras, siendo esta la estrategia que se traduce en un mayor éxito. La nidificación en sustratos artificiales parece común para la especie. El pedúnculo del nido va aumentando en ancho para soportar el peso de los miembros de la colonia. Del mismo modo, las celdas aumentan en altura, de acuerdo con el tamaño de las capas de meconio, lo que permite el alojamiento de los inmaduros. Se sugiere que, al menos para las colonias de postemergentes de P. ferreri, el costo de la construcción del nido no es un factor que limita el desarrollo de las colonias. Por último, los resultados también apoyan la idea de que la reutilización de las celdas es una estrategia ventajosa porque reduce los costos relacionados con la construcción de nuevas celdas.

Recientemente se propusieron dos nuevos indicadores bibliométricos aplicados a la productividad de artículos ISI para una muestra de 120 ecólogos chilenos (sensu lato). El propósito de esos índices fue realizar una corrección del índice-h tanto para el número de coautores como para el número de autocitas, y efectuar una estandarización para la edad científica. Sin embargo, un análisis de los residuos de la regresión del logaritmo decimal del número de alocitas (correlacionado con el índice-h) demostró un bajo efecto del número de coautores y autocitas y demostró que el examen de los residuales es un indicador bibliométrico más robusto. Pese a ello, utilizo esa base de datos y, a través de un análisis de regresión log-log y el empleo del programa computacional LOTKA, demuestro que los ecólogos chilenos no siguen la ley epistemométrica de Lotka (1926), la cual postula que es solo una minoría la que produce la mayoría de los artículos publicados en una determinada área disciplinaria.Recently, two new bibliometric indicators were proposed to gauge the productivity of ISI papers and applied to a sample of 120 Chilean ecologists (sensu lato). The purpose of these indexes was to make a correction of the h-index for the number of coauthors and the number of self-citations as well as to a scientific age-standardization of that index. However, an analysis of residuals from the regression of the logarithm of the number of alocitations (correlated with the h-index) showed little effect of both, the number of coauthors and of self-citations and showed that the examination of the residuals is a more robust bibliometric indicator. Nevertheless, in this comment I use that database and, through a log-log regression analysis and the use of the LOTKA computer program, I show that Chilean ecologists do not follow the scientometric law of Lotka (1926), which postulates that only a minority of authors produces most of the articles published in a particular subject area.

This paper describes the master course design process at the largest institution of higher education in Colorado, USA. The master course design process demonstrated principles of backwards design and employed a team-based approach to course development. The course map was the primary vehicle for communicating the design of the course during development and later for accountability. This case study presented the redesign of General College Botany. The General College Botany curriculum employed authentic assessment and provided an andragogical learning environment. The central authentic assessment in the course was a term-long research project. Other assignments included wiki-building discussions, traditional quizzes, and at-home labs. The accounting of this process and the assignments described for an online science course provide a template for other institutions to follow when considering the implementation of master courses in higher education settings. As botanical curricula continue to be cut from degree programs and the need for remote learning becomes imminent in the modern world, the scaling of educational resources is facilitated by master course design. Master course design promotes accountability and standardization while also affording a well-researched, constructive, and blended learning environment. Evaluative results showed that the master course increased student success and retention in the course.