Miracle-dz/UniFAR-FTUs huggingface dataset:
What Do Platforms Do? Understanding the Gig Economy

The rapid growth of the platform economy has provoked scholarly discussion of its consequences for the nature of work and employment. We identify four major themes in the literature on platform work and the underlying metaphors associated with each. Platforms are seen as entrepreneurial incubators, digital cages, accelerants of precarity, and chameleons adapting to their environments. Each of these devices has limitations, which leads us to introduce an alternative image of platforms: as permissive potentates that externalize responsibility and control over economic transactions while still exercising concentrated power. As a consequence, platforms represent a distinct type of governance mechanism, different from markets, hierarchies, or networks, and therefore pose a unique set of problems for regulators, workers, and their competitors in the conventional economy. Reflecting the instability of the platform structure, struggles over regulatory regimes are dynamic and difficult to predict, but they are sure to gain in prominence as the platform economy grows.
Composting based on moderately thermophilic and aerobic conditions for the production of commercial mushroom growing compost.

Mushroom compost was prepared using an enclosed, environmentally controlled composting (ECC) method, designed to promote rapid substrate decomposition and subsequent establishment of ecological conditions favourable to mushroom culture. Composting aerobically. usually at 54¦C early in processing followed by 47¦C for the majority of processing. produced a compost ready for spawning in 6-8 days. Final compost had a bulk density of 486 kg/m3 (range 440-510 kg/m3) at 70.4% moisture (range 66-75%) and produced average fresh mushroom yields of 19.4 kg per bed m2 (range 22.7-17.3/m2), or 0.66 kg per kg dry compost, in a 3 flush cropping cycle. Disease, or growth of competitive fungi, was not observed. Composting odours were greatly reduced compared to traditional methods. The processing control and uniformity of the ECC method offer much potential for detailed investigation into compost production and ecological and chemical factors in mushroom nutrition.
A new class of q-Hermite-based Apostol-type polynomials and its applications

: The present article is to introduce a new class of q -Hermite based Apostol-type polynomials and to investigate their properties and characteristics. In particular, the generating functions, series expression and explicit and recurrence relations for these polynomials are established. We derive some relationships for q -Hermite based Apostol-type polynomials associated with q -Apostol-type Bernoulli polynomials, q -Apostol-type Euler and q -Apostol-type Genocchi polynomials.
The Signaling Effect of Sampling Size in Online Physical Goods Sampling

Despite the popular use of product sampling as a promotional strategy by retailers, existing research has only studied offline sampling of physical goods and online sampling of information goods, but overlooked online sampling of physical goods. We thus assemble a rich panel-level data set from Taobao to quantify the sales impact of online sampling of physical goods. Based on multiple identification strategies and estimation methods, we find robust evidence that online sampling promotion has a positive relationship with product sales. Specifically, a 1% increase in the number of free samples provided of a product is related to a 0.106% increase in the product’s sales quantity. Additionally, online sampling promotion has the largest sales impact for experience products (sales elasticity = 0.291), followed by search products (sales elasticity = 0.092), and then credence products (insignificant sales elasticity). Furthermore, product popularity does not moderate the sales impact of online sampling, but is twice as effective as online sampling in driving product sales. Our empirical findings provide important contributions to existing product sampling literature, and offer critical managerial implications to online retailers’ promotional strategies.
Ants as Bioindicators of Natural Succession in Savanna and Riparian Vegetation Impacted by Dredging in the Jequitinhonha River Basin, Brazil

We investigated the response of ant species to landscape and geomorphologic parameters of a long‐term (7–11 years) restoration project in the Jequitinhonha River (Northern State of Minas Gerais, Brazil) margins, previously dredged by a diamond mining company. Geomorphological changes from the dredging were severe and the area is unlikely to be adequately restored, mainly due to the negative effects of flooding. Our hypothesis is that ant species assemblages bioindicate successional stages and soil characteristics. We studied the association of effects from the river's flooding zone, the native vegetation, and sedimentary grain size with that of ant species diversity, abundance, and composition. An ant sampling program was conducted in April 2005, using three methods: baits, pitfall traps, and direct collection. Grain size was measured by sieving. In total, 10,784 ants were sampled, belonging to 7 subfamilies, 24 genera and 45 morphospecies. Ant species richness was greater in the undisturbed savanna area than in the restored habitats, and equivalently greater in the ecotone and intermediate zone habitats than on the river bank, the poorest habitat. Atta sexdens rubropilosa indicated a condition related to small forest remnants having well‐structured soil. On the other hand, ants with a body length of under 0.5 cm (Dorymyrmex pyramicus and Pheidole fallax) predominated in sandy areas, where the majority of the granules were the finest. The lack of organic matter and soil structure for constructing suitable nests may prevent large ants from colonizing such areas, and thus inhibit the advance of natural succession.
Oncogene activation of HIV-LTR-driven expression via the NF-ϰB binding sites

: The Raf-1 proto-oncogene product is a highly regulated serine/threonine kinase that functions in signal transduction downstream from growth factor receptors and upstream from nuclear proto-oncogene products. Using a transient cotransfection assay we have found that activated Raf-1 activates expression from the HIV-LTR. Analysis of a series of 5' deletion and point mutations revealed the NF-kappa B motifs as the Raf-responsive element in the HIV-LTR. Moreover, Raf-BXB activated expression from heterologous promoters driven by the HIV NF-kappa B binding sites. In addition to Raf, we show that v-Src, v-H-Ras and v-Mos activate HIV-LTR expression through the NF-kappa B binding sites and v-H-Ras-induced HIV-LTR expression is mediated by Raf-1. These findings may have implications for the involvement of the cellular homologues of these oncogenes in the switch from latent to productive infection by HIV in response to T-cell activation.
The neonate nutrition hypothesis: early feeding affects the body stoichiometry of Daphnia offspring

SUMMARY 1. Aquatic herbivores consume variable quantities and qualities of food. In freshwater systems, where phosphorus (P) is often a primary limiting element, inadequate dietary P can slow maternal growth and reduce body P content. There remains uncertainty about whether and how dietary effects on mothers are transferred to offspring by way of egg provisioning. 2. Using the keystone herbivore Daphnia, we tested a novel explanation (the ‘neonate nutrition hypothesis’) to determine whether the early nutrition of newborns affects their elemental composition and whether the indications of differences in maternal P nutrition found previously might be overestimated. 3. We thus examined the P content of mothers and their eggs from deposition through development to the birth of neonates. We examined further whether very short periods of ingestion (3 h) by the offspring alter the overall P content of juvenile Daphnia. 4. We showed that strong dietary P effects on mothers were not directly transferred to their eggs. Irrespective of the supply of P in the maternal diet, the P content of eggs in different developmental stages and in (unfed) neonates did not differ. This indicates that Daphnia mothers do not reduce the quality (in terms of P) of newly produced offspring after intermittent periods (i.e. several days) of poor nutrition. In contrast, the P content of neonates reflected that of their food after brief periods of feeding, indicating that even temporary exposure to nutrient poor food immediately after birth may strongly affect the elemental composition of neonates. 5. Our results thus support the neonate nutrition hypothesis, which, like differential maternal provisioning, is a possible explanation for the variable elemental quality of young Daphnia.
Permian igneous clasts from the Matzitzi Formation, southern Mexico: isotopic constraints on the final amalgamation of Pangaea

Abstract The tectonic reconstructions of southern Mexico during Late Paleozoic–Middle Triassic time are related to the final stages of Pangaea assembly. Petrographic analysis combined with U–Pb and Hf isotopic analyses of zircon grains belonging to volcanic conglomerate clasts from the Matzitzi Formation in southern Mexico allow characterization of the magmatism at the end of Pangaea accretion. Volcanic pebbles from the Matzitzi Formation have felsic to intermediate compositions and ages ranging from 269 to 285 Ma, which indicate the erosion of a Permian volcanic source. The ɛHf zircon values show two groups with different isotopic signatures. Intermediate hypabyssal samples have εHf(t) values ranging from −7.8 to +0.2 and two-step model ages from 1.6 to 1.7 Ga, suggesting late Paleoproterozoic to Mesoproterozoic crustal residence times. Felsic volcanic samples have εHf(t) values ranging from −3.5 to +8.8 and crustal model ages ranging from 0.7 to 1.5 Ga, suggesting Neo-Mesoproterozoic crustal sources and a juvenile depleted mantle source. Grenvillian grains in volcanic clasts, as well as their isotopic signatures, suggest that the volcanic rocks were emplaced over Mesoproterozoic Oaxaquia-type crust and are related to the Permian–Carboniferous plutonic arc in southern Mexico, which formed along the northwestern Gondwana margin.
A Teaching Experience through the use of Tasks: Limits and possibilities for learning Mathematics in a university context

Context: Rethinking mathematics teaching practices in a university context is an emerging research theme. Objectives: In this article, we aim to discuss the limits and possibilities of using mathematical tasks in the teaching and learning processes of the concepts of Derivative, Integral and the Fundamental Theorem of Calculus. Design: The study is based on a qualitative-interpretative perspective of research, with methodological procedures inspired by a Design-Based Research. Environment and participants: The research was developed with students attending a Functions of a Variable class in a public university in the state of Sao Paulo. Data collection and analysis: Data were collected through mathematical tasks on Differential and Integral Calculus solved by students. The protocols produced were analysed, pointing out the main aspects identified, which led us to organize categories of analysis and dimensions (i) knowledges mobilized and developed by students in relation to mathematical concepts; (ii) main errors and difficulties presented by students in the development of tasks; (iii) limits and possibilities of the practice of exploratory teaching in the university context. Results: The results reveal aspects that characterize a process of resignifying the mathematical concepts discussed with the students and a deepening of their knowledge about the concepts of the DIC. Conclusions: As future notes, we suggest rethinking university teaching practice, since the study indicated possibilities and potentialities of the use of exploratory tasks in the teaching of Differential and Integral Calculus.
Concentration in Saliva and Antibacterial Effect of Xylitol Chewing Gum: In Vivo and In Vitro Study

Purpose. The saliva concentration of xylitol released from two chewing gums was recorded, the first containing xylitol as the only sweetener (100% xylitol) and the second containing only 22% of the polyol. In addition, the in vitro antibacterial effect of the two chewing gums was evaluated. Materials and Methods. The salivary concentration of Xylitol in 32 subjects was determined before and at 0.30, 1.00, 2.00, 5.00, and 10.00 min while using the chewing gums, and at 15.00, 20.00, and 25.00 min after the gums were discarded. In vitro antibacterial activity was determined on a pooled subgingival plaque sample obtained from four patients with periodontal disease. Cariogenic and periodontal bacteria were evaluated before and 15 min, 60 min, and 24 h after gum contact. Results. Using the 100% xylitol chewing gum, saliva levels increased bimodally, one peak after 30 s (1.49 ± 1.41 logμg/L) and a second one at a 10-min evaluation (1.41 ± 1.11 logμg/L); the 22% chewing gum peaked only two minute after contact (1.21 ± 1.24 logμg/L). Overall, a statistically significantly higher salivary concentration of xylitol was detected using the 100% xylitol gum. All bacteria decreased after the addition of the two chewing gums; the 100% gum achieved a greater decrease than the 22% gum. Conclusion. The use of both chewing gums increased the concentrations of xylitol in saliva, with a statistically significantly higher concentration using the 100% xylitol gum. Cariogenic and periodontal bacteria were reduced by both chewing gums; 100% xylitol gum produced the highest and longest lasting effect. This study opens up to the use of xylitol against periodontal disease.
THE EFFECT OF CLIMATE ON THE COLOUR CHANGES OF MOUNTAIN HARES IN SCOTLAND

The seasonal colour changes of mountain hares (Lepus timidus) were studied by standardized field observations in Scotland. The rate of colour change in spring varied according to the climate, being retarded in very cold springs and hastened in mild springs. Hares at high altitudes turned white earlier and more completely than hares at low altitudes, and turned dark later in spring. The colour and moult of different individuals varied greatly. Late-born young turned white later in autumn than fully grown hares. Climate and light cycle are discussed in relation to these colour changes.
Construction by polymerase chain reaction and intragenic DNA probes for three main types of transferable β-lactamases (TEM, SHV, CARB)

Intragenic DNA probes were synthesized by polymerase chain reaction using fragments of the genes of three major types of β-lactamases (TEM, SHV, CARB) as templates. The TEM probe hybridized with the genes encoding TEM-1, TEM-2 and six extended-spectrum related enzymes (TEM-3 to TEM-7, TEM-20) in colony hybridizations and Southern-blot analysis. The SHV probe hybridized with the genes for SHV-1, OHIO-1 and four derived extended-spectrum β-lactamases (SHV-2, SHV-3, SHV-4 and SHV-5). The CARB probe hybridized with the genes for PSE-1 (CARB-2), PSE-4 (CARB-1), CARB-3 and CARB-4. None of the probes hybridized with genes for any of eight oxacillin-hydrolysing enzymes, PSE-2, OXA-1 to OXA-7, ROB-1 and chromosomal β-lactamases of various Enterobacteriaceae (except Klebsiella pneumoniae) and Pseudomonas aeruginosa. Investigations of Escherichia coli clinical isolates using these probes indicate the presence of a novel type of extended-spectrum, transferable β-lactamase.
A review of nineteenth-century records of Sowerby's beaked whale (Mesoplodon bidens)

Data on 27 mesoplodont whales are compiled from the original nineteenth century published records from Britain, Ireland, Europe and the United States. These data comprise the type specimen of Sowerby's beaked whale ( Mesoplodon bidens) and 26 other records, all referred to the taxon M. bidens. Records may include the following information: specimen total length, sex, date of discovery and the locality, pigmentation pattern, external morphology, osteology and soft-tissue anatomy. This information is summarized here from the original descriptions. Only a handful of these specimens was externally complete when described at first hand.
Resistance to Drought and Salinity: Avenues for Improvement

Various techniques for improving the resistance of plants to drought or salinity are discussed in relation to a notional spectrum ranging from rationality to random search. The rational end of the spectrum is exemplified by the control of phenology so that flowering occurs at an optimal time; the random end by wide crosses, such as that between wheat and Elytrigia, which give the remote hope that the high yield-potential of one will combine with the toughness of the other. Most of the techniques occupy the middle ground and involve selecting for characters whose protagonists have strong, but often poorly articulated, hunches that the characters will confer resistance to drought or salinity on the plants possessing them. For drought resistance of grain crops, the possible worth of many of these characters is discussed in relation to their likely impact on improving a crop's ability to (a) extract water from the soil, (b) produce dry matter given a limited water supply, and (c) convert dry matter into grain.
pH-induced solubilization of minerals from casein micelles: influence of casein concentration and ionic strength

The concentrations of cations (calcium and magnesium) and anions (inorganic phosphate, citrate and chloride) have been determined during the acidification of casein micelle suspensions in the pH range 6·7–1·5. The effects of casein concentration (27, 55, 83 and 144 g/kg) and ionic strength (0, 10 and 20 g/kg NaCl added) were investigated. Acidification resulted in solubilization of calcium, magnesium, inorganic phosphate and citrate ions. However, the solubilization curves were different and depended on the casein concentration. Increasing ionic strength by adding NaCl had no effect on acid-induced mineral solubilization. These results were compared with those obtained during milk acidification and discussed in relation to the mineral solubilization that occurs during curd acidification in cheese manufacture.
Developing a passive acoustic monitoring technique for Australia’s most numerous seabird, the Short-tailed Shearwater (Ardenna tenuirostris)

ABSTRACT Establishing appropriate conservation management objectives and actions for seabirds requires timely detection of changes in their populations. However, obtaining regular accurate measures of seabird population size and trends can be difficult due to logistical and financial constraints in accessing remote breeding sites. The Short-tailed Shearwater (Ardenna tenuirostris) is a wide-ranging, burrow-nesting Procellariiform with an estimated breeding population size of ca 23 million individuals. Despite its ecological significance, there is currently limited monitoring of the species. In the present study, eight acoustic data loggers were deployed across six sites over two breeding seasons to assess the efficacy of acoustic monitoring. Five acoustic indices were used to investigate vocal activity over the breeding season, detect phenology events, and to determine the most accurate period to assess the density of occupied nests. The general pattern over the breeding season was similar for several of the acoustic indices and reflected colony attendance patterns. Linear regressions fitted to the normalised difference soundscape index values and density of occupied nests (burrows·m−2) revealed significant relationships in both the incubation and chick-rearing. The results suggest that passive acoustic monitoring could be used as an effective method to predict nesting density in Short-tailed Shearwater breeding colonies. Used in conjunction with information on the breeding colony area, this could enable regular estimates of colony population size. Such information is crucial for the early detection of population trajectory changes. The method may also be applicable for other burrow- or surface-nesting seabirds for which regular wide-spread monitoring currently proves difficult.
Study protocol of a single-arm pre-post study to assess the preliminary effectiveness and feasibility of a home-based bimodal prehabilitation program on preoperative aerobic fitness in high-risk patients scheduled for liver or pancreatic resection

Background: Controversial evidence currently exists regarding the feasibility and effectiveness to improve preoperative aerobic fitness during home-based prehabilitation in patients scheduled for liver or pancreatic resection, whereas morbidity rates are high following these resections. The primary aim of this study is to evaluate the preoperative oxygen uptake (VO 2 ) at the ventilatory anaerobic threshold before and after a four-week home-based preoperative training program with nutritional supplementation in high-risk patients scheduled for elective liver or pancreatic resection. Secondary aims are to evaluate program feasibility, immune system function, cardiopulmonary exercise test responses, individual progression profiles on training responses, quality of life, and postoperative course. Methods: In this multicenter study with a pretest-posttest design, patients with a liver or pancreatic tumor scheduled for elective resection will be recruited. To select the high-risk fraction of this surgical population, their VO 2 at the ventilatory anaerobic threshold should be <11 ml/kg/min for final inclusion. A planned total of 24 high-risk patients will participate in a four-week (three sessions per week) home-based bimodal prehabilitation program. The partly supervised home-based preoperative training program consists of individualized goal setting followed by titration of interval and endurance training on an advanced cycle ergometer, combined with functional task exercises. Additionally, patients will be given protein and vitamin/mineral supplementation. Discussion: Effects of a partly supervised home-based bimodal prehabilitation regimen are unknown in high-risk patients opting for liver or pancreatic resection. Improved preoperative aerobic fitness might translate into improved postoperative outcomes and a reduced demand on care resources. Trial Registration: The study is registered in the Netherlands Trial Registry (NL6151) and was approved by the Institutional Ethics Committee, Twente, Enschede, the Netherlands (P17-08).
Seasonality in the occurrence of the Mediterranean fruit fly [Ceratitis capitata (Wied.)] in the north‐east of Spain

Since the turn of the century, the populations of the Mediterranean fruit fly (Medfly) [Ceratitis capitata (Wied.)] (Dipt., Tephritidae) has steadily increase in the orchards of the Girona Province in the north‐east of Spain, a change which has brought with it considerable damage to fruit grown in that area. In a survey set up to detect the population dynamics of this insect, a large number of Maxitrap® traps containing food‐based lures were hung strategically in peach (224, 208 and 210 traps in the years 2005, 2006 and 2007, respectively), Gala apple (154 traps in 2007) and Fuji apple orchards (97 traps in 2007) in the two main areas where these fruit trees were grown. The results showed a seasonal variation in the population dynamics of the medfly with a peak in September–October, and with adult activity ending in December or January, independently of the kind of host studied. The results take into account the climatic conditions prevailing in each year.