cssi/SciSciGPT-SciSciNet huggingface dataset:
Ball lightning: new physics, new energy source, or just entertainment?

Summary form only given. Ball lightning is a natural phenomenon characterized by a glowing ball of light that forms outside in the open air and inside closed rooms, aircraft, and submarines; floats along at about 1 m/s (even against the prevailing wind) or flies along side aircraft at hundreds of m/s; lasts 1 to 1000 seconds; passes through glass and metal with or without leaving a hole; does no great harm to people on contact or kills them promptly. Ball lightning can reportedly produce impressive artifacts; e.g. excavating ~200 tons of water saturated earth in less than 20 minutes. Since the effects of ball lightning vary considerably, the underlying physics may be very different for different events. Although laboratory experiments have produced a glowing ball of light that lasts for as long as there is a source of electrical power and then decays within a half second, the underlying physics of naturally occurring ball lightning - including its source of energy - is not known. This presentation focuses on cases that leave measurable effects with no apparent connection to a power source. Some effects are consistent with large induced currents. If these effects are caused by a radiating in the TEM mode, then the RF signatures should be observable by satellite and ground based sensors. Observations of long-lived RF bursts are indeed observed with satellite based systems. The following alternate explanations have been examined and found lacking: plasma instabilities, communication signals, radar signals, meteors, and malfunctioning electronics. These observations have not been tied to ball lightning observations. In addition, many and perhaps all of these emissions originated above the ionosphere - based on the lack of frequency chirping of lower frequency components passing through the ionosphere. If these RF bursts are caused by whatever causes ball lightning, then the phenomenon is not limited to the atmosphere and may be more fundamental than atmospheric discharges. The next step is to search for RF signals from ball lightning with a network of ground based sensors. More generally, reported observations are compared to existing theories and a path forward to investigating this elusive phenomenon is proposed
Cdk4/6 Inhibition Induces Epithelial–Mesenchymal Transition and Enhances Invasiveness in Pancreatic Cancer Cells

Aberrant activation of Cyclin D-Cdk4/6 signaling pathway is commonly found in pancreatic ductal adenocarcinoma (PDAC). Here, we show that PD-0332991, a highly specific inhibitor for Cdk4 and Cdk6, exerted growth inhibitory effects on three human PDAC cell lines. Microarray analysis revealed that PD-0332991 downregulated cell-cycle-related genes, but upregulated genes implicated in extracellular matrix (ECM) remodeling and pancreatic cancer cell invasion and metastasis. Moreover, PD-0332991 enhanced invasion in TGF-β-responsive PDAC cell lines that harbor a wild-type SMAD4 gene (COLO-357, PANC-1), but not in TGF-β-resistant AsPC-1 cells that harbor a mutated SMAD4. PD-0332991 also induced epithelial-mesenchymal transition (EMT) in COLO-357 and PANC-1, but not in AsPC-1 cells. Inhibition of CDK4/6 using shRNA mimicked the effects of PD-0332991 on EMT induction. Furthermore, PD-0332991 increased Smad transcriptional activity in luciferase readout assays and activated TGF-β signaling. SB-505124, an inhibitor of the type-I TGF-β receptor (TβRI) kinase, completely blocked EMT induction by PD-0332991. When combined with PD-0332991, SB-505124 inhibited the growth of COLO-357 and PANC-1 cells. Taken together, these data suggest that anti-Cdk4/6 therapy could induce EMT and enhance pancreatic cancer cell invasion by activating Smad-dependent TGF-β signaling, and that combining PD-0332991 and SB-505124 may represent a novel therapeutic strategy in PDAC.
Student Engagement through Faculty Engagement: Faculty Learning Communities as Professional Development

The meaningful collaboration I experienced as a gradate student working with Douglass Seaton at Florida State University created an appreciation for professional development with long-lasting impact. I have recently benefitted from returning to that high level of collaboration with my colleagues in a Faculty Learning Community (FLC). FLCs are long-term, sustainable groups investigating pedagogy in higher education. This article quickly reviews the basic ideas of FLCs, describes the Scholarly Teaching Academy at Appalachian State, and details my research on student engagement in introductory music courses with large enrollments.
Neurodevelopmental test selection, administration, and performance in the main Seychelles child development study.

The Seychelles Child Development Study was designed to provide data on normal neurodevelopment of Seychellois children and to examine the relationship of their neurodevelopmental outcomes to in utero fetal exposure to low concentrations ofmethylmercury from a maternal diet high in fish. This paper outlines the strategies used to select, modify, and field test evaluation tools used in the main longitudinal prospective study of 740 children (95% of the cohort of 779 initially enrolled in 1989). It also gives population statistics and quality assurance data for the tests administered and the evaluation of the home environments.
Creating a Culture of Inquiry

I am certain that you want your students to become lifelong learners. You want them to have a hunger for knowledge that goes well beyond the classroom and well past their formal educational years. You want them to be curious, inquisitive, and eager to learn. For many students, though, it is less likely that this will occur without you leading them toward this goal. This process begins in the classroom as you build a culture of inquiry into your teaching and classroom management.
EEG AFTER INTRACEREBROVENTRICULAR TETRODOTOXIN IN CATS.

SummaryTetrodotoxin injected into the lateral cerebral ventricle of cats produced a reversible loss of volitional control. This syndrome differs from general anesthesia in that the EEG showed a waking pattern which could be “activated” by sensory stimulation throughout the course of motor dysfunction. The behavioral effects of lateral ventricular procaine mimicked those of tetrodotoxin, but procaine interfered with EEG activation due to sensory stimulation.
A Comparison of Learning Outcomes in Skills-Based Courses: Online Versus Face-To-Face Formats

In comparing the learning outcomes of online versus face-to-face courses, skills-based forms of instruction have received little attention. This study asks the question “Can skills-based courses taught online achieve the same outcomes as face-to-face courses in which the instructor and students interacting in real time may have higher levels of interaction, thus potentially facilitating higher levels of skill improvement?” If so, what are the critical success factors that influence these outcomes? These questions are examined by comparing four classes in negotiations (two face-to-face and two online) taught by the same professor. The courses were designed to be as similar as possible except for their delivery method. Results indicate that face-to-face learners earned higher negotiation outcomes than online learners even when using the same technology. Suggestions are offered for improving outcomes.
Study of Low Temperature Sintered LiZn Ferrites Prepared by Sol-Gel Method

The Li0.5-0.5xZnxMna Fe2.5-0.5x-aO4 (0.1x0.6) ferrites were prepared by sol-gel method. The XRD spectra of two kinds of powders prepared by the chelating agent of citric acid and polyethylene alcohol (PVA), are compared. The XRD spectra of the powders from the citrate precursor show that the formation of spinel phase LiZn ferrites begins from 400℃ and ends at 600℃ with particle size of 6-22 nm. The powders prepared by PVA chelating agent exhibit complicate XRD spectra involving two phases. The curves of sintering shrinkage versus temperature and the SEM photographs of samples sintered at temperature from 800 to 880℃ are illustrated for the powders (L54, L03) having different activity because of different processes, which demonstrats that the sintering behaviors of the LiZn ferrites powders depend strongly on the activity of the powder. The abnormal grain growth was observed on SEM photographs. The sintering temperature decreases with increasing Bi2O3 content, and the sintering at temperature Ts bellow 900℃ can be achieved by using 0.25mol%Bi2O3. The drawing of the saturation magnetization Ms and the ferromagnetic resonance linewidth ΔH versus zinc content was shown for the specimens of Li0.5-0.5xZnxMna Fe2.5-0.5x-aO4 ferrite sintered at 880+20℃.
Creep-fatigue interaction and thermo-mechanical fatigue behaviors of thermoplastics and their composites

Abstract Creep-fatigue interaction and thermo-mechanical fatigue (TMF) behaviors of injection molded thermoplastic composites were investigated. Talc-filled polypropylene and short glass fiber reinforced polypropylene, polyamide-6.6, and a blend of polyphenylene-ether and polystyrene were used for the experimental study. Trapezoidal load signal with hold time periods was used for the creep-fatigue testing. Effects of temperature, frequency, load level, and hold-stress position on creep-fatigue interaction behavior were studied. In-phase TMF tests were conducted on polyamide-based composites for the temperature variation between 85 and 120 °C. Significant non-linearity was observed for the interaction of creep and fatigue damage. The applicability of Chaboche non-linear creep-fatigue interaction model to predict creep-fatigue and TMF lives for thermoplastic composites was investigated. A frequency term was added to the model to consider the beneficial effect of increased frequency observed for some thermoplastics. More than 90% of the life predictions by the Chaboche model were within a factor of 2 of the experimental life for both creep-fatigue and TMF test conditions.
Quadrivalent HPV vaccine prevented cervical neoplasia caused by HPV-16 and HPV-18.

Source Citation The Future II Study Group. Quadrivalent vaccine against human papillomavirus to prevent high-grade cervical lesions. N Engl J Med. 2007;356:1915-27. 17494925
A "Caged" Luciferin for Imaging Cell-Cell Contacts.

Cell–cell interactions underlie fundamental biological processes but remain difficult to visualize over long times and large distances in tissues and live organisms. Bioluminescence imaging with luciferase–luciferin pairs is sufficiently sensitive to image cells in vivo but lacks the spatial resolution to identify cellular locations and interactions. To repurpose this technology for visualizing cellular networks, we developed a “caged” luciferin that produces light only when cells are in close contact. This molecule comprises a nitroaromatic core that can be selectively reduced (“uncaged”) by one cell type, liberating a luciferin that can be selectively consumed by neighboring, luciferase-expressing cells. When the two cell types are in contact, robust light emission is observed. This imaging strategy will enable the noninvasive visualization of cell–cell interactions relevant to organismal biology.
Exploring Electron/Proton Transfer and Conformational Changes in the Nitrogenase MoFe Protein and FeMo-cofactor Through Cryoreduction/EPR Measurements

We combine cryoreduction/annealing/EPR measurements of nitrogenase MoFe protein with results of earlier investigations to provide a detailed view of the electron/proton transfer events and conformational changes that occur during early stages of [e-/H+] accumulation by the MoFe protein. This includes reduction of (i) the non-catalytic state of the iron-molybdenum cofactor (FeMo-co) active site that is generated by chemical oxidation of the resting-state cofactor (S = 3/2)) within resting MoFe (E0), and (ii) the catalytic state that has accumulated n =1 [e-/H+] above the resting-state level, denoted E1(1H) (S ≥ 1) in the Lowe-Thorneley kinetic scheme. FeMo-co does not undergo a major change of conformation during reduction of oxidized FeMo-co. In contrast, FeMo-co undergoes substantial conformational changes during the reduction of E0 to E1(1H), and of E1(1H) to E2(2H) (n = 2; S = 3/2). The experimental results further suggest that the E1(1H) → E2(2H) step involves coupled delivery of a proton and electron (PCET) to FeMo-co of E1(H) to generate a non-equilibrium S = ½ form E2(2H)*. This subsequently undergoes conformational relaxation and attendant change in FeMo-co spin state, to generate the equilibrium E2(2H) (S = 3/2) state. Unexpectedly, these experiments also reveal conformational coupling between FeMo-co and P-cluster, and between Fe protein binding and FeMo-co, which might play a role in gated ET from reduced Fe protein to FeMo-co.
Population genomic evidence for multiple Pliocene refugia in a montane-restricted harvestman (Arachnida, Opiliones, Sclerobunus robustus) from the southwestern United States

The integration of ecological niche modelling into phylogeographic analyses has allowed for the identification and testing of potential refugia under a hypothesis-based framework, where the expected patterns of higher genetic diversity in refugial populations and evidence of range expansion of nonrefugial populations are corroborated with empirical data. In this study, we focus on a montane-restricted cryophilic harvestman, Sclerobunus robustus, distributed throughout the heterogeneous Southern Rocky Mountains and Intermontane Plateau of southwestern North America. We identified hypothetical refugia using ecological niche models (ENMs) across three time periods, corroborated these refugia with population genetic methods using double-digest RAD-seq data and conducted population-level phylogenetic and divergence dating analyses. ENMs identify two large temporally persistent regions in the mid-latitude highlands. Genetic patterns support these two hypothesized refugia with higher genetic diversity within refugial populations and evidence for range expansion in populations found outside hypothesized refugia. Phylogenetic analyses identify five to six genetically divergent, geographically cohesive clades of S. robustus. Divergence dating analyses suggest that these separate refugia date to the Pliocene and that divergence between clades pre-dates the late Pleistocene glacial cycles, while diversification within clades was likely driven by these cycles. Population genetic analyses reveal effects of both isolation by distance (IBD) and isolation by environment (IBE), with IBD more important in the continuous mountainous portion of the distribution, while IBE was stronger in the populations inhabiting the isolated sky islands of the south. Using model-based coalescent approaches, we find support for postdivergence migration between clades from separate refugia.
Compressive sensing based initial beamforming training for massive MIMO millimeter-wave systems

The abundant spectrum at millimeter-wave (mmWave) has the potential to greatly increase the capacity of 5G cellular systems. However, to overcome the high pathloss in the mmWave frequencies, beamforming with large antenna arrays is required at both the base station and user equipments for sufficient link budget. This feature is a challenge for beamforming training during initial access due to low SNR and poor synchronization. A recently developed compressive sensing (CS) based training algorithm exploits channel sparsity but it is vulnerable to phase error from poor synchronization. We propose a novel CS-based algorithm that tracks and compensates frequency offset and phase noise. Simulation results show that the proposed method improves achievable rate by 10 times compared with existing CS-based method during initial beamforming training.
Quantitative assessment and validation of a stroke rehabilitation game

We explore a quantitative assessment for a Microsoft Kinect-based stroke rehabilitation virtual reality (VR) video game, Mystic Isle, by evaluating three assessment metrics of player hand movement- maximum range (extension), peak velocity and mean velocity. We also analyze the left-right hand symmetry by visualizing trajectories of both hands throughout the game. Assessment metrics obtained by the Kinect-based game have been validated using a Vicon motion capture system. The percentage errors of maximum range and mean velocity are less than 10%. The peak velocity metric is more sensitive to noise and sampling rate with a percentage error up to 18%.
Direct measurement of aerosol glass fiber alignment in a DC electric field

ABSTRACTWe report non-conducting aerosol fiber (i.e., glass fiber) alignment in a DC electric field. Direct observation of fiber orientation state is demonstrated and quantitative analysis of fiber alignment is made using phase contrast microscopy in four different conditions: (i) dry air and naturally charged fibers, (ii) humid and naturally charged, (iii) humid and neutralized (Boltzmann charge distribution), and (iv) humid and neutralized with an electrostatic precipitator upstream electrodes (i.e., non-charged). The glass fiber aerosols generated by a vortex shaking method were conditioned using a Po-210 neutralizer or humidifier and were provided into a test unit where cylindrical or parallel plate electrodes are used and high voltage is applied to them. Fibers were collected on a filter immediately downstream from the electrodes and their images were taken through an optical microscope to visualize the fiber orientation and measure the alignment angles and lengths of the fibers. The results showed t...
Pathologically Confirmed Alzheimer's Disease in APOE ɛ2 Homozygotes is Rare but Does Occur.

BACKGROUND Homozygous APOEɛ4 status is a well-known risk factor in the development of Alzheimer's disease (AD). However, other genotypes of APOE have not yet been found to have equal clinical significance. There is a paucity of reports regarding clinically or pathologically described AD in APOEɛ2 homozygotes compared to the other alleles. OBJECTIVE To notify clinicians that patients with homozygous APOEɛ2 are also at risk of developing AD based on results from the largest prospectively gathered registry of brain samples to date. METHODS We queried the National Alzheimer's Coordinating Center (NACC) database for autopsy-confirmed AD cases. Of the Uniform Data Set (UDS) participants who are deceased, 5,779 were diagnosed with dementia at their last UDS visit prior to death, and autopsy data is available for 3,518. RESULTS Of the brains in the NACC database with pathologically confirmed dementia, seven were found to be homozygous for APOEɛ2, which represents only 0.2% of the autopsy-confirmed sample. Furthermore, pathology-confirmed AD represents 29% (2/7) of the APOEɛ2/ɛ2 patients diagnosed with dementia. CONCLUSIONS Although rare, autopsy-confirmed AD can be present in APOEɛ2/ɛ2 carriers.
Direct current stimulation of endothelial monolayers induces a transient and reversible increase in transport due to the electroosmotic effect

We investigated the effects of direct current stimulation (DCS) on fluid and solute transport across endothelial cell (EC) monolayers in vitro. Our motivation was transcranial direct current stimulation (tDCS) that has been investigated for treatment of neuropsychiatric disorders, to enhance neurorehabilitation, and to change cognition in healthy subjects. The mechanisms underlying this diversity of applications remain under investigation. To address the possible role of blood-brain barrier (BBB) changes during tDCS, we applied direct current to cultured EC monolayers in a specially designed chamber that generated spatially uniform direct current. DCS induced fluid and solute movement across EC layers that persisted only for the duration of the stimulation suggesting an electroosmosis mechanism. The direction of induced transport reversed with DCS polarity – a hallmark of the electroosmotic effect. The magnitude of DCS-induced flow was linearly correlated to the magnitude of the applied current. A mathematical model based on a two-pore description of the endothelial transport barrier and a Helmholtz model of the electrical double layer describes the experimental data accurately and predicts enhanced significance of this mechanism in less permeable monolayers. This study demonstrates that DCS transiently alters the transport function of the BBB suggesting a new adjunct mechanism of tDCS.
A Meta-Analysis Characterizing Stem-Like Gene Expression in the Suprachiasmatic Nucleus and Its Circadian Clock

Cells expressing proteins characteristic of stem cells and progenitor cells are present in the suprachiasmatic nucleus (SCN) of the adult mammalian hypothalamus. Any relationship between this distinctive feature and the master circadian clock of the SCN is unclear. Considering the lack of obvious neurogenesis in the adult SCN relative to the hippocampus and other structures that provide neurons and glia, it is possible that the SCN has partially differentiated cells that can provide neural circuit plasticity rather than ongoing neurogenesis. To test this possibility, available databases and publications were explored to identify highly expressed genes in the mouse SCN that also have known or suspected roles in cell differentiation, maintenance of stem-like states, or cell-cell interactions found in adult and embryonic stem cells and cancer stem cells. The SCN was found to have numerous genes associated with stem cell maintenance and increased motility from which we selected 25 of the most relevant genes. Over ninety percent of these stem-like genes were expressed at higher levels in the SCN than in other brain areas. Further analysis of this gene set could provide a greater understanding of how adjustments in cell contacts alter period and phase relationships of circadian rhythms. Circadian timing and its role in cancer, sleep, and metabolic disorders are likely influenced by genes selected in this study.
Effect of the Mediterranean Diet on Cancer Reduction

The Mediterranean diet is a plant-based dietary pattern characterized by high intake of olive oil, legumes, whole grains, fruit, vegetables, nuts, seeds, fish, and red wine. The diet has been linked to a decreased risk of developing many non-communicable diseases including several types of cancer. Although findings have been somewhat inconsistent, several large prospective cohort studies have shown an association between greater adherence to a traditional Mediterranean diet and lower overall cancer incidence. When specific forms of cancer are examined, current research suggests a stronger association with some types and a weaker or non-existent relationship with others. Existing literature is equivocal on the association between the Mediterranean diet and breast cancer, but studies are heterogeneous in menopausal status and tumor hormone receptor status. For colorectal cancer, data is reasonably consistent to suggest that adherence to the Mediterranean diet is associated with a reduced risk, although more studies are needed to confirm and refine the relationship. Evidence for a protective association of a Mediterranean dietary pattern on upper gastrointestinal cancers is quite consistent and suggests that the Mediterranean diet is associated with a reduction of risk. It should be noted that due to the small number of studies, more data, especially from non-European countries, is needed. Suggested mechanisms through which the Mediterranean diet may impact cancer initiation and proliferation include increased insulin sensitivity and reduction of excess insulin production, anti-inflammatory and antioxidant effects of the diet, high fiber content and an association with reduced risk of excess weight gain and obesity.
Using Environmental Education Project Curricula with Elementary Preservice Teachers

Few studies have focused on the use of the Project WET, WILD, WILD Aquatic, and Learning Tree Guides as a means of introducing environmental education (EE) in preservice settings. Four different case studies demonstrate methods of integrating EE through the use of the Project Guides into preservice teacher coursework at four different universities. The integration methods strengthen elementary preservice teachers’ science content knowledge, develop science process and inquiry skills, integrate literacy, and introduce fieldwork. Elementary preservice teachers in all four cases reported positive teaching and learning experiences from their use of the Project Guides.
A Preliminary Analysis of the Logged Questions that Students Ask in Introductory Computer Science.

Asking questions is widely believed to contribute to student learning, but little is known about the questions that students ask or how to exploit them in tutorial interventions to help students learn. This paper presents a preliminary analysis of student questions from an introductory computer science course, logged automatically when students requested help during open lab consulting hours. The data set consists of one hundred and forty two questions that introductory computer science students asked while working on four weekly programming assignments. The initial data suggest that student questions can be repetitive in nature and different students ask different kinds of questions. The paper concludes by suggesting that an analysis technique that is more sophisticated than cosine similarity applied to raw text with stop words removed will be necessary to classify student initiated questions.
Ultrasonic Velocity Measurements Applied to Process Control of Metal Matrix Composites Densification

Discontinuous metal-matrix composites are emerging as advanced materials for applications requiring high performance isotropic mechanical properties. They offer significant improvement in the mechanical and physical properties over conventional monolithic alloys which can result in significant weight savings. They also have the advantage of tailoring certain properties to meet specific requirements. There are, however, some impediments that adversely limit the use of metal-matrix composites, such as production cost and lack of suitable nondestructive techniques to be applied for the control of processing parameters used in their manufacturing[1]. The control of these parameters will result in the manufacturing of composites with uniform properties and the detection of defects at early stages of processing cycles, which reduce manufacturing cost and enhance productivity.
Outcomes in patients with head and neck squamous cell carcinoma (HNSCC) requiring salvage resection after definitive therapy.

e17572Background: Salvage surgical resection is often offered in HNSCC patients who develop locally recurrent disease after definitive therapy. However, survival outcomes are often poor and subsequ...
Machine Learning as Grounded Theory: Human-Centered Interfaces for Social Network Research through Artificial Intelligence:

Internet technologies have created unprecedented opportunities for people to come together and through their collective effort generate large amounts of data about human behavior. With the increase...
Gender-Based Violence Prevention Workshops: An Experimental Evaluation of Efficacy

Gender-based violence has become an increasingly visible and salient public problem. In the Fall of 2015, the University of Connecticut’s Violence Against Women Prevention Program (VAWPP) implemented interactive workshops in first-year experience (FYE) classes to reduce rape myth acceptance, improve knowledge and understanding of the University’s affirmative consent policy, and increase confidence in interpreting cues related to sexual consent. This randomized experimental design tested whether these outcomes were realized as a result of the workshops. In almost all instances, the workshops substantially and statistically significantly decreased students’ rape myth acceptance, increased their knowledge and understanding of consent, and improved their confidence in cue interpretation.
Cashing in on the File-System Cache

We consider the disk cache (file-system cache) information channel, and show how it can be exploited on various systems to yield potentially sensitive information. Our approach can be used locally by an unprivileged adversary to detect whether another user is writing to disk, and if so, the rate at which data is being written. Further, we also show how an attacker can detect whether specific files have been recently accessed by the victim. We then extend this attack to remote access through a web server, using timing analysis to identify recent access of chosen pages.
Association of metabolic syndrome with glioblastoma: a retrospective cohort study and review.

Background Metabolic syndrome is identified as a risk factor for the development of several systemic cancers, but its frequency among patients with glioblastoma and its association with clinical outcomes have yet to be determined. The aim of this study was to investigate metabolic syndrome as a risk factor for and affecting survival in glioblastoma patients. Methods A retrospective cohort study, consisting of patients with diagnoses at a single institution between 2007 and 2013, was conducted. Clinical records were reviewed, and clinical and laboratory data pertaining to 5 metabolic criteria were extrapolated. Overall survival was determined by time from initial surgical diagnosis to date of death or last follow-up. Results The frequency of metabolic syndrome among patients diagnosed with glioblastoma was slightly greater than the frequency of metabolic syndrome among the general population. Within a subset of patients (n = 91) receiving the full schedule of concurrent radiation and temozolomide and adjuvant temozolomide, median overall survival was significantly shorter for patients with metabolic syndrome compared with those without. In addition, the presence of all 5 elements of the metabolic syndrome resulted in significantly decreased median survival in these patients. Conclusions We identified the metabolic syndrome at a slightly higher frequency in patients with diagnosed glioblastoma compared with the general population. In addition, metabolic syndrome with each of its individual components is associated with an overall worse prognosis in patients receiving the standard schedule of radiation and temozolomide after adjustment for age.
Incorporation of heavy metals in experimentally grown foraminifera from Sapelo Island, Georgia and Little Duck Key, Florida, U.S.A.

Abstract Benthic foraminifera are valuable indicators in environmental studies, including those on marine pollution monitoring. While a great deal of foraminiferal biomonitoring research utilizes abundance and distributional data, further value resides in better understanding the incorporation of heavy metal pollutants in foraminiferal calcite. By experimentally growing assemblages of foraminifera from propagules (small juveniles) gathered from Sapelo Island, Georgia and Little Duck Key, Florida, this study examines foraminiferal incorporation of the heavy metals arsenic, cadmium, nickel, and zinc over a range of concentrations. Surface sediment was collected and sieved to concentrate the propagules. The propagules were then used to experimentally grow assemblages with each exposed to a different heavy metal. After one month, the experimentally grown foraminifera were harvested and samples of the two most common species from each location, Ammonia tepida (Cushman) and Haynesina germanica (Ehrenberg) from Sapelo Island and Quinqueloculina sabulosa (Cushman) and Triloculina oblonga (Montagu) from Little Duck Key, were selected for trace element analysis. Calcite of the tests was analyzed using LA-ICP-MS to quantify the heavy metal incorporation. Rotalid species A. tepida and H. germanica incorporated more cadmium as its concentration in the surrounding water increased, whereas miliolid species Q. sabulosa and T. oblonga incorporated more of the metals zinc and nickel. This study shows that while foraminiferal incorporation of heavy metals has great potential as a biomonitoring tool, multiple factors (especially inter-clade variation) must be considered carefully. In future marine environmental research, these factors may help to create a more targeted assessment of environmental pollution.
A Granular Physics-Based View of Fault Friction Experiments

Rate‐ and State‐dependent Friction (RSF) equations are commonly used to describe the time‐dependent frictional response of fault gouge to perturbations in sliding velocity. Among the better‐known v...
Evaluation of lactose oxidase as enzymatic antifungal control for Penicillium spoilage in yogurt

ABSTRACT In this study, we investigated the antifungal activity of lactose oxidase (LO) as a potential biopreservative in dairy products. Our study objectives were to screen antifungal activity of LO against common mold strains, to detect the minimum inhibitory level of LO against the same strains, and to understand how LO affects the pH and lactic acid bacteria (LAB) counts in set yogurt. Five mold strains (Penicillium chrysogenum, Penicillium citrinum, Penicillium commune, Penicillium decumbens, and Penicillium roqueforti) were used throughout study. These strains were previously isolated from dairy manufacturing plants. Throughout the study, yogurts were stored at 21 ± 2°C for 14 d. Antifungal activity of LO was screened using 2 enzyme levels (1.2 and 12 g/L LO) against selected strains on the surface of a miniature laboratory set-yogurt model. For all tested strains, no visible mold growth was detected on the surface of yogurts covered with LO compared with control yogurt without LO. The minimum inhibitory level of LO against each strain was further investigated using 4 enzyme levels (0.12, 0.48, 0.84, and 1.2 g/L LO) on the miniature laboratory set-yogurt model. We detected 0.84 g/L LO as the minimum level inhibiting visible hyphal growth across strains. The minimum inhibitory level of LO varied for each individual strain. To study the effect of LO on the pH of yogurt, miniature laboratory set-yogurt models were covered with different enzyme levels (0.12, 0.48, 0.84, 1.2, and 12 g/L LO). At d 14, a difference was detected comparing pH values of treatments to control with no LO. Commercial low-fat set yogurt was used to study the effect of LO on LAB survival when yogurt surface was covered with 0.84 g/L LO under the same experimental conditions. Control with no LO was included. At d 14, 3 levels of catalase were added (0, 0.01, and 0.1%) to each treatment. To enumerate LAB, homogenized samples were plated on de Man, Rogosa, and Sharpe agar and incubated. Yogurts with 0.84 g/L LO had lower LAB counts compared with control yogurts, and catalase level did not have a significant effect on LAB counts. Our results demonstrated potential antifungal efficacy of LO against common spoilage organisms in dairy products with residual lactose and relatively low pH. Manufacturers should establish efficacy of LO against mold strains of interest and determine the effects of LO on organoleptic properties and LAB survival in set yogurt.
Carbon Monoxide Generated by Heme Oxygenase-1 Suppresses the Rejection of Mouse-to-Rat Cardiac Transplants

Mouse-to-rat cardiac transplants survive long term after transient complement depletion by cobra venom factor and T cell immunosuppression by cyclosporin A. Expression of heme oxygenase-1 (HO-1) by the graft vasculature is critical to achieve graft survival. In the present study, we asked whether this protective effect was attributable to the generation of one of the catabolic products of HO-1, carbon monoxide (CO). Our present data suggests that this is the case. Under the same immunosuppressive regimen that allows mouse-to-rat cardiac transplants to survive long term (i.e., cobra venom factor plus cyclosporin A), inhibition of HO-1 activity by tin protoporphyrin, caused graft rejection in 3--7 days. Rejection was associated with widespread platelet sequestration, thrombosis of coronary arterioles, myocardial infarction, and apoptosis of endothelial cells as well as cardiac myocytes. Under inhibition of HO-1 activity by tin protoporphyrin, exogenous CO suppressed graft rejection and restored long-term graft survival. This effect of CO was associated with inhibition of platelet aggregation, thrombosis, myocardial infarction, and apoptosis. We also found that expression of HO-1 by endothelial cells in vitro inhibits platelet aggregation and protects endothelial cells from apoptosis. Both these actions of HO-1 are mediated through the generation of CO. These data suggests that HO-1 suppresses the rejection of mouse-to-rat cardiac transplants through a mechanism that involves the generation of CO. Presumably CO suppresses graft rejection by inhibiting platelet aggregation that facilitates vascular thrombosis and myocardial infarction. Additional mechanisms by which CO overcomes graft rejection may involve its ability to suppress endothelial cell apoptosis.
Asymptotic Expansions of Singularly Perturbed Chandrasekear Type of Equations

The singular perturbation theory provides a powerful design and analysis approach for model order reduction. Another method of simplifying the calculation of feedback gains in a LQG problem is the Chandrasekhar algorithm, which replaces the usual Riccati approach. The method presented in this paper combines the advantages inherent in the singular perturbation theory with those of the Chandrasekhar algorithm. This is accomplished after an asymptotic power series solution is constructed and analyzed. Then, the terms of the asymptotic series can be computed via a simpler way, since they involve the solution of lover dimensional sub-problems of the Chandrasekhar type.
Situated cognition and learning environments: implications for teachers on- and offline in the new digital media age

John Seely Brown suggested that learning environments should be spaces in which all work is public, is subject to iterative critique by instructors and peers, and in which social interaction is primary. In such spaces, students and teachers engage in a situated cognition approach to teaching and learning where “cognitive accomplishments rely in part on structures and processes outside the individual”. Here we describe a qualitative analysis of a socially situated learning setting that aimed to develop children who can design, analyze, critique, and transform media, subjecting existing social media, their designs, and their peers’ designs to public and iterative critique. In this setting, adult mentors supported children’s self-expression, self-reflection, and skillbuilding through authentic, socially situated reading, writing, and discussion, and media production. Creating and leveraging such spaces is essential for preparing all children for successful experiences in the new knowledge economy in formal a...
Passive-dynamic ankle-foot orthosis replicates soleus but not gastrocnemius muscle function during stance in gait: Insights for orthosis prescription.

Background:Passive-dynamic ankle–foot orthosis characteristics, including bending stiffness, should be customized for individuals. However, while conventions for customizing passive-dynamic ankle–f...
Final Remarks on the Binary Hypothesis for the Be Stars

The hypothesis that a significant fraction of Be stars are interacting binaries is discussed in general terms. The author believes that the observed Be stars are a mixture of three different types of objects. The weakest point of the single-star hypothesis is probably the difficulty in explaining the quasi-periodic V/R variations; the weakest point of the binary hypothesis appears to be the statistical expectancy of a fairly high number of eclipsing systems among them.
Quality evaluation of plateletpheresis using the new AMICUS (Baxter) cell separator: evolution of CD 62 expression.

The purpose of this study was to evaluate the new AMICUS (Baxter-Fenwal Division) cell separator in terms of donor safety, efficiency, and quality of the product obtained. One hundred eighty-three single-donor plateletpheresis procedures were performed, using a collection of 4-4.5 x 10 11 platelets as endpoint. During the first part of the study, the mean volume processed was 3,225 ml and the mean procedure duration 69.5 min. During the second part, after a software change, the mean volume and mean procedure time were 3,071 ml and 68.3 min, respectively. According to local policy, every collection bag was separated into two therapeutic units each containing a mean of 1.87 (1.83) x 10 11 platelets. The white blood cell (WBC) contamination per therapeutic unit was less than 5 x 10 6 in 91% of phereses performed in part one of the study and in 98% of phereses performed in part two. During the recommended 5 days storage, sequential in vitro analyses were performed in 27 units, showing limited platelet activation according to CD62 expression and morphological changes on electron microscopy (EM). Furthermore, there was a correlation between CD62 expression and the degree of WBC contamination (P = 0.03). In conclusion, platelet collection with the new Amicus allows for high platelet yields of adequate quality as judged by WBC content, CD62 expression, and electron microscopic morphological changes.
Limitations on the Atmospheric Thermal Effects for High-Power CO 2 Laser Beams*

A theoretical analysis has been performed of the nonlinear thermal processes associated with the atmospheric absorption of 10.6-μm radiation from laser beams of high power density, with special attention to limitations imposed upon the CO2 absorption rate by the induced-emission phenomenon. Differential equations relating atmospheric absorption and temperature change are formulated to include this and related high power effects, and are solved numerically for a series of power densities, humidities, and altitudes near sea level. Low power formulas are shown to be unreliable above 104 W/cm2, with absorption-saturation processes especially effective in limiting the magnitude of the CO2 cooling at these large values of the laser power density. Analytic expressions are derived, which provide an accurate description of the temperature profile during the cooling phase. The regions of validity for simplified high and low power approximations to these formulas are also discussed.
Using NTEE to classify non-profit organisations: an assessment of human service and regional applications

The National Taxonomy of Exempt Entities (NTEE) constitutes a major contribution to the field of non-profit research, but is beset by conceptual and practical problems. The application of the taxonomy to the list of charitable organisations recognised by the US Internal Revenue Service (IRS) is also an important resource for research, although it has limitations as well, especially for industry-specific and regional analyses. Using survey data from the Chicago metropolitan region, I show that regional estimates for human services based on only those charitable organisations which are required to file tax returns may miss over 40 per cent of the total number of organisations and under-estimate total revenues by almost half. Finally, I point to conceptual, technical and institutional challenges that must be addressed if the NTEE is to gain maximum utility.
Stimulation of human pepsin output by topical hydrochloric acid

Pepsin secretion is stimulated by the back-diffusion of acid across the mucosa of the vagally denervated canine pouch. If back-diffusion is enhanced by damage, pepsin secretion increases. The current study investigates whether this mechanism exists in man. The stomachs of normal human volunteers were irrigated for 1 hour with either buffer or 0.01 N HCl, 1 hour with 0.2 N HCl, and a final hour with buffer or 0.01 N HCl. During the middle hour both the concentration and output of pepsin increased three- or fourfold. From these studies it appears that the human gastric mucosa contains a mechanism similar to the dog's which results in the stimulation of pepsin secretion when exposed to acid. This mechanism could be of etiologic significance in gastric ulcer disease, which has been shown to be associated with increased gastric-musocal permeability.
Dielectric characterization using patch antennas

In this paper, complex permittivities of lossy dielectric mixtures with a wide range of permittivity values are characterized with a patch antenna using near field techniques. Permittivity range explored is from 8 to 80. Measurements are carried out in the 1–2GHz frequency range and the magnitude and phase response from reflection measurements are acquired using a Network Analyzer. Transfer functions are generated using both magnitude and phase to estimate the real and imaginary part of the permittivity. Comparative study is done for the estimation error when only one parameter is used in the estimation as opposed to using multiple parameters in the regression. Complex permittivity measurements from Agilent probe kit 85070 are used as reference values for the empirical models.
Effects of amino acids and α‐amanitin on bovine embryo development in a simple protein‐Free medium

Five experiments, utilizing 3741 embryos produced in vitro, were designed to test the effects of Eagle's nonessential amino acids, and combinations of Eagle's essential amino acids and the RNA polymerase inhibitor alpha-amanitin on the development of preimplantation bovine embryos in a modified protein-free KSOM medium. Embryos were cultured in 5% O2:5% CO2:90% N2 at 39 degrees C for the first 40-44 hr in modified KSOM, and embryos with > or = 4 cells were cultured in modified KSOM-PVA with different amino acids in experiments 1-4, and with the addition of alpha-amanitin in experiment 5. In experiment 1, addition of 0.5x of the essential amino acids, with different concentrations of nonessential amino acids significantly increased hatching of blastocysts and decreased blastocyst degeneration, but increasing the nonessential amino acids from 1x to 5x, did not stimulate embryo development. In experiments 2-4, increasing only the glycine concentration, or adding each of the 12 essential amino acids singly or several in combination to the medium containing nonessential amino acids, did not significantly improve embryo development. Taurine (0.4 mM) in the modified KSOM medium reduced blastocyst degeneration. In experiment 5, alpha-amanitin (20 microM) completely inhibited further embryo development when it was added at several stages from 4-cell embryos to morulae. The study with protein-free KSOM plus amino acids provided a completely defined simple medium for culturing bovine embryos, with evidence that continuous mRNA activity and presumed protein synthesis was obligatory to meet the complex and continuous requirements for proteins by the developing blastocyst.