Essential Design Elements for Successful Online Courses

This article describes a study of how students perceive and interact with web-based education, with the intent of improving the experience. In particular, the study aimed to understand how undergraduate students learn classical geological laboratory ideas and skills through activity-based instruction via the internet. The focus of this case study was an embryonic web-based course in introductory geology. Over the 2-year study the website expanded and improved iteratively based on feedback from students each term. The study was descriptive in nature and was intended to discover the basic nature of an effective website, regardless of its complexity. The authors suggest several basic rules for pedagogical design of online courses. Educational levels: Graduate or professional

Revisiting "Tin in South-eastern Europe?"

Obnovom arheoloških iskopavanja antičkog kastela Timakum Minus 2019. godine stvorile su se nove mogućnosti za tumačenja njegovih građevina koje su istraživane pre više decenija. Među ostacima građevina oko antičkog kastela Timacum Minus-a posebnu pažnju privlači delimično istražen "objekat sa hipokaustom", naročito u pogledu njegovih konstruktivnih karakteristika. Pored inače čestih antičkih konstrukcija hipokausta i zidnog grejanja, među ostacima ove građevine uočena je i posebna vrsta građevinskih elemenata - keramičke cevi za svodove. Velika količina otkrivenih cevi ukazala je na to da je ova građevina zaista imala svodove izrađene od njih. Iako je pojava cevi za svodove prilikom istraživanja antičkih lokaliteta na tlu jugoistočne Evrope registrovana, ona nije dovoljno dokumentovana, kao što ni sama funkcija cevi često nije prepoznata. Jedan od razloga za to jeste nedovoljna upućenost istraživača u specifične karakteristike cevi za svodove i njihovu funkciju, usled čega se one mešaju sa vodovodnim cevima, tubulusima ili kalemovima vezanim za zidno grejanje - budući da svaki od tih elemenata pripada keramičkim proizvodima koji su namenjeni građevinarstvu. U radu su razmatrane karakteristike cevi za svodove na Timakum Minusu, kao i kontekst u kome su pronađene unutar "objekta sa hipokaustom". Na osnovu nalaza pečata kohorte Aurelije II Daradanorum određeno je da "objekat sa hipokaustom" i konstrukcija svodova od keramičkih cevi potiču iz III veka - u kome je i inače pojava tih svodova širom Rimskog carstva bila česta. Prilikom sistematizacije vrsta keramičkih cevi na Timakum Minusu posebno je izdvojena ona koje je bilo najviše u "objektu sa hipokaustom". U sklopu nje je prepoznat i sasvim specifičan centralni element koji je omogućavao da se dva niza cevi na istom pravcu, ali iz suprotnih smerova, međusobno spoje. Taj element je definisao oblik svoda kojim su bile pokrivene prostorije čiju je rekonstrukciju osnove bilo moguće izvršiti. Arhitektonske analize "objekta sa hipokaustom", kao i karakteristike uočene na samim cevima ukazale su na to da su prostorije bile pokrivene poluobličastim svodom, izgrađenim od lučnih vertikalnih nizova cevi koje su u temenu bile ,,zaključane" centralnim elementom. Rekonstrukcija izgleda cevi i načina njihovog ređanja uklapa se u hronologiju izvođenja objekta i svoda tokom III veka. Daljim statičkim analizama došlo se do još nekoliko saznanja. Pokazalo se da je preko svoda morao biti nanesen određen sloj malterne mase da bi debljina svoda dosegla optimalnu vrednost u opsegu 20-30 cm. Na osnovu proporcija objekta koje su određene u njegovoj osnovi ispitana je visina objekta, gde je grupa slučajeva takođe definisana proporcionalno. Prema našim analizama, zidovi prostorija "objekta sa hipokaustom" u kojima su cevi registrovane mogli su dosezati visinu do 3,08 m, dok je visina prostorija u temenu svoda mogla biti 6,16 m. Ovim istraživanjem pokušali smo da ukažemo na veliki značaj pojedinačnih arhitektonsko-građevinskih elemenata, a među njima i keramičkih cevi za svodove, kojima se često ne pridaje dovoljna pažnja. Nalazi keramičkih cevi za svodove u Timakum Minusu, uz izvršene arhitektonske analize, upotpunjuju sliku otkrivenog "objekta sa hipokaustom" iz više aspekata. Posebno je značajno definisanje njegove visine, koje je veoma teško za antičke građevine profane arhitekture na našem tlu budući da su najčešće sačuvane u prizemnoj ili temeljnoj zoni. Značaj nalaza keramičkih cevi za svodove u Timakum Minusu veliki je stoga što je on omogućio kako konkretno definisanje konteksta njihovog nalaza tako i rekonstrukciju oblika određenih delova građevine pomoću tog elementa, što do sada nije istraživano prilikom analiza antičke arhitekture na tlu jugoistočne Evrope.The important role of the Balkans in the origin and development of metallurgy is well established with respect to copper. In addition, Aleksandar Durman, in his 1997 paper "Tin in South-eastern Europe?", essentially initiated studies into the role of the Balkans in Europe's Bronze Age tin economy. He identified six geologically favourable sites for tin mineralisation and associated fluvial placer deposits in the former Yugoslavian republics, and suggested that these may have added to the tin supply of the region. The viability of two of these sites has been confirmed (Mt Cer and Bukulja, Serbia) but the exploitation potential for the other locations has remained untested. River gravels from these four sites (Motajica and Prosara in Bosnia and Herzegovina; Bujanovac in Serbia; Ogražden in North Macedonia) were obtained by stream sluicing and panning. The sites of Prosara and Bujanovac were found to be barren with respect to cassiterite (SnO 2). Streams flowing from Motajica and Ogražden were both found to contain cassiterite, but in amounts several orders of magnitude less than at Mt Cer and Bukulja. Although it is possible that minor tin recovery occurred at Motajica and Ogražden, it is unlikely that they could have contributed meaningfully to regional tin trade. This is supported by the fact that the isotopic signature (d 124 Sn) of cassiterite from Motajica is highly enriched in light isotopes of tin compared to that associated with Late Bronze Age artefacts of the region

Effect of Nest Box Temperature Mitigation Treatments on Nest Success and Nestling Condition in a Southeastern Population of Eastern Bluebirds (Sialia sialis)

Understanding behavioral responses of wildlife to climate change will be important as global temperatures continue to rise. Effects of rising temperatures may impact many species, including those that breed in seemingly protected nests, such as cavity nesting birds. Variations in nest cavity microclimate during the early development of secondary cavity nesting passerines may affect the growth of offspring and impact nesting success and survival. We examined the effect of two heat mitigation treatments (white exterior, n=11, and an internal foil heat shield, n=16) and nest box opening orientation (north, south, east, west) on internal nest box temperatures and the effect of internal nest box temperature on nest success and nestling development in a population of Eastern Bluebirds (Sialia sialis) at a restored grassland in central Georgia. We predicted that nest boxes receiving a heat treatment would experience cooler internal temperatures and fledge more offspring of higher body condition compared to control next boxes (n=23). Nest boxes were checked approximately every 3 to 4 days between April and mid-August 2020 and 2021 to record nesting activity and nestling measurements (tarsus and weight). Internal nest box temperature was recorded hourly between April 1st and June 28th using remote data loggers installed on the inside wall of each box. We calculated the maximum daily, minimum nightly and overall averages per nesting attempt and examined the relations of each variable with nestling weight and tarsus length to test the effect of temperature on nest success. White paint applied to the exterior of nest boxes was effective in producing cooler thermal environments compared to control and foil boxes. However, both painted nest boxes and boxes that experienced cooler nightly low temperatures were less likely to be successful. This study highlight the importance of investigating species-specific responses to increasing temperatures before implementing wide-scale habitat modifications

Why doesn’t every family practice rainwater harvesting? Factors that affect the decision to adopt rainwater harvesting as a household water security strategy in central Uganda

© 2018, © 2018 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. This article investigates the reasons householders do, and don’t, adopt domestic rainwater harvesting (DRWH). Using a mixed-methods research approach, we collected data in three districts in central Uganda. Factors that emerged as important with respect to uptake of DWRH to address water shortage, especially at the household scale, include the work of intermediary organizations, finance mechanisms, life course dynamics and land tenure

Genetic-geographic correlation revealed across a broad European ecotypic sample of perennial ryegrass (Lolium perenne) using array-based SNP genotyping

KEY MESSAGE: Publically available SNP array increases the marker density for genotyping of forage crop,Lolium perenne. Applied to 90 European ecotypes composed of 716 individuals identifies a significant genetic–geographic correlation. ABSTRACT: Grassland ecosystems are ubiquitous across temperate and tropical regions, totalling 37 % of the terrestrial land cover of the planet, and thus represent a global resource for understanding local adaptations to environment. However, genomic resources for grass species (outside cereals) are relatively poor. The advent of next-generation DNA sequencing and high-density SNP genotyping platforms enables the development of dense marker assays for population genetics analyses and genome-wide association studies. A high-density SNP marker resource (Illumina Infinium assay) for perennial ryegrass (Lolium perenne) was created and validated in a broad ecotype collection of 716 individuals sampled from 90 sites across Europe. Genetic diversity within and between populations was assessed. A strong correlation of geographic origin to genetic structure was found using principal component analysis, with significant correlation to longitude and latitude (P < 0.001). The potential of this array as a resource for studies of germplasm diversity and identifying traits underpinning adaptive variation is highlighted. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00122-015-2556-3) contains supplementary material, which is available to authorized users

Detection of genetically modified organisms (GMOs) using isothermal amplification of target DNA sequences

BACKGROUND: The most common method of GMO detection is based upon the amplification of GMO-specific DNA amplicons using the polymerase chain reaction (PCR). Here we have applied the loop-mediated isothermal amplification (LAMP) method to amplify GMO-related DNA sequences, 'internal' commonly-used motifs for controlling transgene expression and event-specific (plant-transgene) junctions. RESULTS: We have tested the specificity and sensitivity of the technique for use in GMO studies. Results show that detection of 0.01% GMO in equivalent background DNA was possible and dilutions of template suggest that detection from single copies of the template may be possible using LAMP. CONCLUSION: This work shows that GMO detection can be carried out using LAMP for routine screening as well as for specific events detection. Moreover, the sensitivity and ability to amplify targets, even with a high background of DNA, here demonstrated, highlights the advantages of this isothermal amplification when applied for GMO detection

Estimating Mixing Heights Using Microwave Temperature Profiler

A paper describes the Microwave Temperature Profiler (MTP) for making measurements of the planetary boundary layer thermal structure data necessary for air quality forecasting as the Mixing Layer (ML) height determines the volume in which daytime pollution is primarily concentrated. This is the first time that an airborne temperature profiler has been used to measure the mixing layer height. Normally, this is done using a radar wind profiler, which is both noisy and large. The MTP was deployed during the Texas 2000 Air Quality Study (TexAQS-2000). An objective technique was developed and tested for estimating the ML height from the MTP vertical temperature profiles. In order to calibrate the technique and evaluate the usefulness of this approach, estimates from a variety of measurements during the TexAQS-2000 were compared. Estimates of ML height were used from radiosondes, radar wind profilers, an aerosol backscatter lidar, and in-situ aircraft measurements in addition to those from the MTP

Analysis of historical selection in winter wheat

KEY MESSAGE: Modeling of the distribution of allele frequency over year of variety release identifies major loci involved in historical breeding of winter wheat. ABSTRACT: Winter wheat is a major crop with a rich selection history in the modern era of crop breeding. Genetic gains across economically important traits like yield have been well characterized and are the major force driving its production. Winter wheat is also an excellent model for analyzing historical genetic selection. As a proof of concept, we analyze two major collections of winter wheat varieties that were bred in Western Europe from 1916 to 2010, namely the Triticeae Genome (TG) and WAGTAIL panels, which include 333 and 403 varieties, respectively. We develop and apply a selection mapping approach, Regression of Alleles on Years (RALLY), in these panels, as well as in simulated populations. RALLY maps loci under sustained historical selection by using a simple logistic model to regress allele counts on years of variety release. To control for drift-induced allele frequency change, we develop a hybrid approach of genomic control and delta control. Within the TG panel, we identify 22 significant RALLY quantitative selection loci (QSLs) and estimate the local heritabilities for 12 traits across these QSLs. By correlating predicted marker effects with RALLY regression estimates, we show that alleles whose frequencies have increased over time are heavily biased toward conferring positive yield effect, but negative effects in flowering time, lodging, plant height and grain protein content. Altogether, our results (1) demonstrate the use of RALLY to identify selected genomic regions while controlling for drift, and (2) reveal key patterns in the historical selection in winter wheat and guide its future breeding. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00122-022-04163-3