Defining Technology for Learning: Cognitive and Physical Tools of Inquiry

This essay explores definitions of technology and educational technology. The authors argue the following points: 1. Educational stakeholders, and the public at large, use the term technology as though it has a universally agreed upon definition. It does not, and how technology is defined matters. 2. For technology in schools to support student learning, it must to be defined in a way that describes technology as a tool for problem-solving. 3. Integration of technology, particularly when paired with teacher-centered practices, has the potential of reinforcing and heightening the negative consequences of a conception of learning that positions students as recipients of knowledge instead constructors of knowledge. Essay concludes with a call for leaders in the field of educational technology to provide guidance by adopting a definition that encapsulates the third point above

An investigation of herpes simplex virus promoter activity compatible with latency establishment reveals VP16-independent activation of immediate-early promoters in sensory neurones

Herpes simplex virus (HSV) type-1 establishes lifelong latency in sensory neurones and it is widely assumed that latency is the consequence of a failure to initiate virus immediate-early (IE) gene expression. However, using a Ore reporter mouse system in conjunction with Ore-expressing HSV-1 recombinants we have previously shown that activation of the IE ICPO promoter can precede latency establishment in at least 30 % of latently infected cells. During productive infection of non-neuronal cells, IE promoter activation is largely dependent on the transactivator VP16 a late structural component of the virion. Of significance, VP16 has recently been shown to exhibit altered regulation in neurones; where its de novo synthesis is necessary for IE gene expression during both lytic infection and reactivation from latency. In the current study, we utilized the Ore reporter mouse model system to characterize the full extent of viral promoter activity compatible with cell survival and latency establishment. In contrast to the high frequency activation of representative IE promoters prior to latency establishment, cell marking using a virus recombinant expressing Ore under VP16 promoter control was very inefficient. Furthermore, infection of neuronal cultures with VP16 mutants reveals a strong VP16 requirement for IE promoter activity in non-neuronal cells, but not sensory neurones. We conclude that only IE promoter activation can efficiently precede latency establishment and that this activation is likely to occur through a VP16-independent mechanism

Exploring the Efficacy of Consumer Education with Regard to Consumption of Branded and Luxury Counterfeit Merchandise

This study presents the topic of counterfeiting, its negative consequences and the fight against this illegal business. Consumer education was explored as a method of altering future purchase intentions of counterfeit merchandise. Results indicate strong support for the efficacy of a consumer education seminar with regard to knowledge, attitudes, and planned behavior toward the consumption of counterfeit merchandise. on demographic factors. After the educational seminar, students had a greater understanding of counterfeiting, felt more knowledgeable about the topic, acknowledged that it is illegal, realized how it affects the global economy and retailers, and linked it to social issues such as organized crime, terrorism, child labor, and sweatshops. In congruence with scholars who suggest consumer education as a vehicle to decrease counterfeit consumption, participants agreed that this seminar was educational and informative, and an effective means towards minimalizing the consumption patterns of counterfeit merchandise

Pollen microphotographs from Georgia, Caucasus.

Contains 166 photographs of pollen grains that are commonly encountered in sediments from Georgia, are difficult to identify or are endemic to the regio

Gold-alkynyls in catalysis : Alkyne activation, gold cumulenes and nuclearity

The use of cationic gold(i) species in the activation of substrates containing CC bonds has become a valuable tool for synthetic chemists. Despite the seemingly simple label of 'alkyne activation', numerous patterns of reactivity and product structure are observed in systems employing related substrates and catalysts. The complications of mechanistic determination are compounded as the number of implicated gold(i) centres involved in catalysis increases and debate about the bonding in proposed intermediates clouds the number and importance of potential reaction pathways. This perspective aims to illustrate some of the principles underpinning gold-alkynyl interactions whilst highlighting some of the contentious areas in the field and offering some insight into other, often ignored, mechanistic possibilities based on recent findings

MaNGA galaxy properties -- II. A detailed comparison of observed and simulated spiral galaxy scaling relations

We present a catalogue of dynamical properties for 2368 late-type galaxies from the MaNGA survey. The latter complements the catalogue of photometric properties for the same sample based on deep optical DESI photometry processed with AutoProf. Rotation curves (RCs), extracted by model fitting H$\alpha$ velocity maps from the MaNGA Data Analysis Pipeline, extend out to 1.4 (1.9) R$_{e}$ for the primary (secondary) MaNGA samples. The RCs and ancillary MaNGA Pipe3D data products were used to construct various fundamental galaxy scaling relations that are also compared uniformly with similar relations from NIHAO zoom-in simulations. Simulated NIHAO galaxies were found to broadly reproduce the observed MaNGA galaxy population for $\log (M_*/{\rm M_{\odot}) > 8.5}$. Some discrepancies remain, such as those pertaining to central stellar densities and the diversity of RCs due to strong feedback schemes. Also presented are spatially-resolved scatters for the velocity-size-stellar mass (VRM$_*$) structural relations using MaNGA and NIHAO samples. The scatter for these relations in the galaxian interiors is a consequence of the diversity of inner RC shapes, while scatter in the outskirts is dictated by the large range of stellar surface densities which itself is driven by sporadic star formation. The detailed spatially-resolved scatter analysis highlights the complex interplay between local and global astrophysical processes and provides a strong constraint to numerical simulations.Comment: 21 pages, 13 Figures, Accepted for publication in MNRA

Associations between Sociodemographics and Pediatric Osteosarcoma Characteristics

https://openworks.mdanderson.org/sumexp23/1022/thumbnail.jp

Infected Necrosis in Severe Pancreatitis - Combined Nonsurgical Multi-Drainage with Directed Transabdominal High-Volume Lavage in Critically Ill Patients

Background: Infection of pancreatic necrosis is a life-threatening complication during the course of acute pancreatitis. In critically ill patients, surgical or extended endoscopic interventions are associated with high morbidity and mortality. Minimally invasive procedures on the other hand are often insufficient in patients suffering from large necrotic areas containing solid or purulent material. We present a strategy combining percutaneous and transgastric drainage with continuous high-volume lavage for treatment of extended necroses and liquid collections in a series of patients with severe acute pancreatitis. Patients and Methods: Seven consecutive patients with severe acute pancreatitis and large confluent infected pancreatic necrosis were enrolled. In all cases, the first therapeutic procedure was placement of a CT-guided drainage catheter into the fluid collection surrounding peripancreatic necrosis. Thereafter, a second endosonographically guided drainage was inserted via the gastric or the duodenal wall. After communication between the separate drains had been proven, an external to internal directed high-volume lavage with a daily volume of 500 ml up to 2,000 ml was started. Results: In all patients, pancreatic necrosis/liquid collections could be resolved completely by the presented regime. No patient died in the course of our study. After initiation of the directed high-volume lavage, there was a significant clinical improvement in all patients. Double drainage was performed for a median of 101 days, high-volume lavage for a median of 41 days. Several endoscopic interventions for stent replacement were required (median 8). Complications such as bleeding or perforation could be managed endoscopically, and no subsequent surgical therapy was necessary. All patients could be dismissed from the hospital after a median duration of 78 days. Conclusion: This approach of combined percutaneous/endoscopic drainage with high-volume lavage shows promising results in critically ill patients with extended infected pancreatic necrosis and high risk of surgical intervention. Neither surgical nor endoscopic necrosectomy was necessary in any of our patients. Copyright (C) 2009 S. Karger AG, Basel and IA

Breast Milk from Tanzanian Women has Divergent Effects on Cell-Free and Cell-Associated HIV-1 Infection in Vitro.

Transmission of HIV-1 during breastfeeding is a significant source of new pediatric infections in sub-Saharan Africa. Breast milk from HIV-positive mothers contains both cell-free and cell-associated virus; however, the impact of breast milk on HIV-1 infectivity remains poorly understood. In the present study, breast milk was collected from HIV-positive and HIV-negative Tanzanian women attending antenatal clinics in Dar es Salaam. Milk was analyzed for activity in vitro against both cell-free and cell-associated HIV-1. Potent inhibition of cell-free R5 and X4 HIV-1 occurred in the presence of milk from all donors regardless of HIV-1 serostatus. Inhibition of cell-free HIV-1 infection positively correlated with milk levels of sialyl-Lewis(X) from HIV-positive donors. In contrast, milk from 8 of 16 subjects enhanced infection with cell-associated HIV-1 regardless of donor serostatus. Milk from two of these subjects contained high levels of multiple pro-inflammatory cytokines including TNFα, IL-1β, IL-6, IL-8, MIP-1α, MIP-1β, MCP-1 and IP-10, and enhanced cell-associated HIV-1 infection at dilutions as high as 1∶500. These findings indicate that breast milk contains innate factors with divergent activity against cell-free and cell-associated HIV-1 in vitro. Enhancement of cell-associated HIV-1 infection by breast milk may be associated with inflammatory conditions in the mother and may contribute to infant infection during breastfeeding