cssi/SciSciGPT-SciSciNet huggingface dataset:
Assessing social vulnerability of villages in Mt. Kasigau area, Kenya, using the analytical hierarchy process

This research assesses the social vulnerability of five villages (Jora, Kiteghe, Makwasinyi, Bungule, and Rukanga) in Mt. Kasigau, Kenya. Our goal was to develop a social vulnerability model by adopting a vulnerability conceptual framework that conceptualizes vulnerability into three major components: exposure, sensitivity, and adaptive capacity and using the analytical hierarchy process (AHP). Employing the AHP, the three components of vulnerability were decomposed into its constituent components and structured into a hierarchical format where each component was represented by different societal and environmental criterions and stressors. Next, we performed a pairwise comparison at each level of the hierarchy to obtain local priorities. Finally, we aggregated the local priorities from the bottom up to obtain global priorities of the social vulnerability of each village. The results from this study revealed that Makwasinyi was the most vulnerable village followed by Bungule, Kiteghe, Jora, and Rukanga respectively. Further, the results suggested that adaptive capacity and exposure played a critical role in determining the social vulnerability compared to sensitivity. Considering this, reducing social vulnerability in the area should focus much on improving the adaptive capacity of the people and reducing their exposure specifically in Makwasinyi village.
Catalysis-Hub.org, an open electronic structure database for surface reactions.

We present a new open repository for chemical reactions on catalytic surfaces, available at https://www.catalysis-hub.org . The featured database for surface reactions contains more than 100,000 chemisorption and reaction energies obtained from electronic structure calculations, and is continuously being updated with new datasets. In addition to providing quantum-mechanical results for a broad range of reactions and surfaces from different publications, the database features a systematic, large-scale study of chemical adsorption and hydrogenation on bimetallic alloy surfaces. The database contains reaction specific information, such as the surface composition and reaction energy for each reaction, as well as the surface geometries and calculational parameters, essential for data reproducibility. By providing direct access via the web-interface as well as a Python API, we seek to accelerate the discovery of catalytic materials for sustainable energy applications by enabling researchers to efficiently use the data as a basis for new calculations and model generation.
External Validation of Generic and Cancer-Specific Risk Stratification Criteria for Predicting 30-Day Mortality in Patients Presenting with Pulmonary Embolism and Active Cancer

Abstract Introduction: The Hestia criteria has been established as a highly sensitive prognostic tool used by clinicians to identify newly diagnosed pulmonary embolism (PE) patients from the general population at low vs. high risk of early (30 day) mortality. Font et al. applied similar risk stratification criteria in a population restricted to PE patients with cancer. We evaluated the performance of the generic Hestia tool and cancer-specific criteria by Font et al. for predicting 30-day post-PE mortality in patients with active cancer. Methods: We identified consecutive, adult, objectively confirmed PE patients with active cancer presenting to the emergency department at our institution from 11/2010-1/2014. We calculated the proportion of patients categorized as low-risk by each set of criteria and determined the accuracy of the criteria for predicting 30-day all-cause mortality. Mortality was determined through Social Security Death Index searches. Results: A total of 124 patients with PE and active cancer (mean age 66.2 years, 46.0% with concurrent deep vein thrombosis, 49.2% with metastatic disease and 46.8%, 16.9% and 10.4% receiving chemotherapy, radiation or both, respectively) were included. Mortality at 30-days occurred in 25 (20.2%) patients. The Hestia tool had a sensitivity of 100% but classified 90% for >24 hours (n=19). Conclusion: In this external validation study, both the generic Hestia tool and cancer-specific Font et al. risk stratification criteria displayed acceptable sensitivity. Compared to Hestia, the Font et al. criteria classified two times as many patients as low-risk. Larger, prospective studies are needed to confirm our results. Download : Download high-res image (85KB) Download : Download full-size image Disclosures Coleman: Janssen Pharmaceuticals: Consultancy, Research Funding; Bayer Pharmaceuticals AG: Consultancy, Research Funding; Boehringer-Ingelheim Pharmaceuticals, inc.: Consultancy, Research Funding.
A positron emission tomography occupancy study of brexpiprazole at dopamine D2 and D3 and serotonin 5-HT1A and 5-HT2A receptors, and serotonin reuptake transporters in subjects with schizophrenia.

The objective of this study (NCT01854944) was to assess D2/D3, 5-HT1A, 5-HT2A and serotonin transporter (SERT) occupancies of brexpiprazole in adult subjects with schizophrenia in order to identify the in vivo pharmacologic profile that may be relevant to the antipsychotic, antidepressant, and side effect profiles of the drug. Subjects were grouped into three independent cohorts of four subjects each. All subjects underwent positron emission tomography (PET) scans with two different radiotracers at baseline prior to brexpiprazole administration, and again on Day 10 after daily doses of either 4 mg (Cohorts 1 and 2), or 1 mg (Cohort 3). Cohort 1 received scans with [11C]-(+)-PHNO to measure D2 and D3 receptor occupancy and [11C]CUMI101 to measure 5-HT1A occupancy; Cohort 2 received [11C]MDL100907 for 5-HT2A occupancy and [11C]DASB for SERT occupancy; Cohort 3 underwent scanning with [11C]-(+)-PHNO and [11C]MDL100907. Five female and seven male subjects, aged 42 ± 8 years (range, 28–55 years), participated in this study. Dose dependency was observed at D2 receptors, with occupancies reaching 64 ± 8% (mean +/− SD) following 1 mg/day and 80 ± 12% following 4 mg/day. D3 receptor availability increased following 1 mg brexpiprazole treatment and did not change with 4 mg. Robust and dose-related occupancy was also observed at 5-HT2A receptors. Negligible occupancy (<5%) was observed at 5-HT1A and SERT at 4 mg/day. In summary, brexpiprazole demonstrated in vivo binding to D2 receptors and 5-HT2A receptors at steady state after 10 days of daily administration in a dose dependent manner, while binding to D3, 5-HT1A receptors and SERT was not detectable with the radiotracers used for these targets. This pharmacologic profile is consistent with the observed antipsychotic and antidepressant effects.
The Effect of Stirrup Length on Impact Attenuation and Its Association With Muscle Strength.

Keener, MM, Critchley, ML, Layer, JS, Johnson, EC, Barrett, SF, and Dai, B. The effect of stirrup length on impact attenuation and its association with muscle strength. J Strength Cond Res XX(X): 000-000, 2020-Horseback-riders have a high prevalence of low back injuries, which may be related to the repetitive low back impacts experienced in riding. The purposes of this study were to quantify the effect of 3 stirrup lengths and 2 riding styles on the peak acceleration experienced by the rider and the association between the peak acceleration and the rider's different elements of muscle strength. Thirteen female riders performed a sitting or rising trot at each of the 3 stirrup lengths (2-point length, mid-seat length, or dressage length), while the acceleration of the tibia, sacrum, seventh cervical vertebra (C7), and head were collected. Subjects completed a push-up, a vertical jump, and 4 core exercises to assess upper-body strength, lower-body strength, and core endurance, respectively. Peak acceleration of the sacrum, C7, and head were generally lower in the standing phase of the rising trot compared with the sitting phase of either the sitting or rising trot, particularly at the shortest stirrup length. Peak acceleration of the sacrum, C7, and head decreased as the stirrup length was shortened in the standing phase of the rising trot. Canonical correlations showed nonsignificant correlations between strength measurements and peak acceleration. Riding with more weight supported through the legs with a short stirrup length may decrease low back impacts and their associated injury risk. Technique training is likely needed to encourage riders to use lower-body and core strength for impact attenuation.
The Work Opportunity and Welfare-to-Work Tax Credits: Participation Rates Among Eligible Workers

This paper examines participation in the Work Opportunity Tax Credit (WOTC) and the Welfare-to-Work Tax Credit (WtW), two federal employer subsidy programs. I use nationally-representative data to ...
A Systematic Review of Peripheral Neuropathies in Breast Cancer-Related Lymphedema.

Controversy exists regarding the influence of breast cancer–related lymphedema (BCRL) in the development of peripheral neuropathies. Our aim was to evaluate the association of secondary lymphedema ...
The impact of phased university reopenings on mitigating the spread of COVID-19: a modeling study.

BACKGROUND: Several American universities have experienced COVID-19 outbreaks, risking the health of their students, employees, and local communities. Such large outbreaks have drained university resources and forced several institutions to shift to remote learning and send students home, further contributing to community disease spread. Many of these outbreaks can be attributed to the large numbers of active infections returning to campus, alongside high-density social events that typically take place at the semester start. In the absence of effective mitigation measures (e.g., high-frequency testing), a phased return of students to campus is a practical intervention to minimize the student population size and density early in the semester, reduce outbreaks, preserve institutional resources, and ultimately help mitigate disease spread in communities. METHODS: We develop dynamic compartmental SARS-CoV-2 transmission models to assess the impact of a phased reopening, in conjunction with pre-arrival testing, on minimizing on-campus outbreaks and preserving university resources (measured by isolation bed capacity). We assumed an on-campus population of N = 7500, 40% of infected students require isolation, 10 day isolation period, pre-arrival testing removes 90% of incoming infections, and that phased reopening returns one-third of the student population to campus each month. We vary the disease reproductive number (Rt) between 1.5 and 3.5 to represent the effectiveness of alternative mitigation strategies throughout the semester. RESULTS: Compared to pre-arrival testing only or neither intervention, phased reopening with pre-arrival testing reduced peak active infections by 3 and 22% (Rt = 1.5), 22 and 29% (Rt = 2.5), 41 and 45% (Rt = 3.5), and 54 and 58% (improving Rt), respectively. Required isolation bed capacity decreased between 20 and 57% for values of Rt ≥ 2.5. CONCLUSION: Unless highly effective mitigation measures are in place, a reopening with pre-arrival testing substantially reduces peak number of active infections throughout the semester and preserves university resources compared to the simultaneous return of all students to campus. Phased reopenings allow institutions to ensure sufficient resources are in place, improve disease mitigation strategies, or if needed, preemptively move online before the return of additional students to campus, thus preventing unnecessary harm to students, institutional faculty and staff, and local communities.
Animal Response to Toxic and Non-Toxic Tall Fescue

Tall fescue (Festuca arundinacea Schreb.J is currently grown on about 35 million acres in the United States. It has been utilized extensively for grazing cattle, especially in the south central and southeastern regions. Performance of cattle grazing tall fescue has been quite variable, especially during the warm summer season. Reduced performance during this time is often referred to as the summer syndrome, summer slump or summer fescue toxicosis. This syndrome is characterized by reduced gains, elevated body temperature, increased respiration rate, excess salivation, long rough hair coat, decreased milk production and standing in the shade and wet places.
Results of a Multicenter Phase II Trial of Brentuximab Vedotin as Second-Line Therapy before Autologous Transplantation in Relapsed/Refractory Hodgkin Lymphoma

Abstract This multicenter prospective phase II study examines the activity and tolerability of brentuximab vedotin as second-line therapy in patients with Hodgkin lymphoma that was relapsed or refractory after induction therapy. Brentuximab vedotin (1.8 mg/kg) was administered i.v. on day 1 of a 21-day cycle for a total of 4 cycles. Patients then proceeded to autologous hematopoietic cell transplantation (AHCT), if eligible, with or without additional salvage therapy, based on remission status after brentuximab vedotin. The primary endpoint was overall response rate (ORR). Secondary endpoints were safety, stem cell mobilization/collection, AHCT outcomes, and association of CD68+ with outcomes. Of 37 patients, the ORR was 68% (13 complete remission, 12 partial remission). The regimen was well tolerated with few grade 3/4 adverse events, including lymphopenia (1), neutropenia (3), rash (2), and hyperuricemia (1). Thirty-two patients (86%) were able to proceed to AHCT, with 24 patients (65%) in complete remission at time of AHCT. Thirteen patients in complete remission, 4 in partial remission, and 1 with stable disease (49%) received AHCT without salvage combination chemotherapy. CD68 expression did not correlate with response to brentuximab vedotin. The median number of stem cells mobilized was 6.0 × 106 (range, 2.6 to 34), and median number of days to obtain minimum collection (2 × 106) was 2 (range, 1 to 6). Brentuximab vedotin as second-line therapy is active, well tolerated, and allows adequate stem cell collection and engraftment. For Hodgkin lymphoma patients with relapsed/refractory disease after induction therapy, second-line brentuximab vedotin, followed by combination chemotherapy for residual disease, can effectively bridge patients to AHCT.
Memory Conscious Task Partition and Scheduling in Grid Environments

While resource management and task scheduling are identified challenges of Grid computing, current Grid scheduling systems mainly focus on CPU and network availability. Recent performance improvement of CPU and computer network has made memory usage a significant factor of overall performance. In this study, we consider memory availability as a performance factor and introduce memory conscious task partition and scheduling. Three task partition policies are discussed. They are CPU-based, memory-based, and CPU-memory combined partition. We first investigate the three task partition policies on dedicated resources and verify the effectiveness of the CPU-memory combined partition algorithm in finding an optimal solution. We then extend the task partition policies in non-dedicated environments with the consideration of resource sharing. Analytical and experimental results show that the CPU-memory combined scheduling approach outperforms either the CPU-based or memory-based scheduling approach considerably for memory-intensive applications in Grid environments.
Large dose furosemide therapy for hypertension: Long-term use in 22 patients

Abstract A retrospective study of 22 hypertensive patients receiving large oral doses of furosemide (80 to 640 mg daily for 32 ± 7 months) and standard antihypertensive therapy was performed. All patients had moderately severe or severe hypertension. The substitution of furosemide for the previous diuretic agents resulted in a 22 percent average reduction in arterial pressure and significant improvement in the clinical status of 15 patients. The addition of furosemide allowed a reduction in the dose of antihypertensive medication in four patients. Besides preventing the sodium retention and extracellular fluid volume expansion associated with standard antihypertensive agents, large doses of furosemide may have exerted an additional antihypertensive effect. The combination of orally administered furosemide and standard antihypertensive therapy permitted better control of arterial pressure than that obtained with previous diuretic-antihypertensive combinations in the patients studied. The overall safety of large dose furosemide therapy for extended periods of time appears to be relatively good.
Further Experimental Study of H2O-LH2 Heat Exchangers

At the Nuclear Rocket Development Station (NRDS) in Nevada, heat exchangers are under construction that will convert large quantities of liquid hydrogen to ambient temperature hydrogen gas using water as the heat source. In a previous paper [1] results were presented from a scale model H2O-LH2 heat exchanger built and tested at this laboratory. During the past year heat transfer was studied in the small model incorporating a twisted tape swirl inducer and in 2 passes (160 ft) of the 4.06-in. ID full-scale unit. The results of both these investigations are discussed herein.
Parallel and Serial Processing

This chapter reviews theoretical and empirical progress that has been made in answering the question “Is processing parallel or serial?” Answers to the question are complicated because the distinction between parallel and serial processing interacts with other basic distinctions, including exhaustive versus self-terminating search, limited versus unlimited capacity, discrete versus continuous processing, and stochastic versus functional independence. Because of these complications, parallel and serial models readily mimic each other's predictions. Empirical answers to the question are complicated as well because different procedures invoke parallel and serial processing in different ways, and because detailed theories of empirical phenomena often mimic each other's predictions. The chapter reviews progress in distinguishing parallel and serial models of memory search, visual search, dual-task performance, redundant stimulation, and memory retrieval. It addresses recent alternatives to parallel processing, such as coactivation and mixture models. It ends by evaluating the amount of cumulative progress that has been made in answering the question “Is processing parallel or serial?” and by speculating about prospects for progress in the future. Keywords: attention; automaticity; dual tasks; limited capacity; memory search; parallel processing; reaction time; serial processing; skill acquisition; unlimited capacity; visual search
Magma storage beneath Axial volcano on the Juan de Fuca mid-ocean ridge

Axial volcano, which is located near the intersection of the Juan de Fuca ridge and the Cobb–Eickelberg seamount chain beneath the northeast Pacific Ocean, is a locus of volcanic activity thought to be associated with the Cobb hotspot1. The volcano rises 700 metres above the ridge, has substantial rift zones extending about 50 kilometres to the north and south, and has erupted as recently as 1998 (ref. 2). Here we present seismological data that constrain the three-dimensional velocity structure beneath the volcano. We image a large low-velocity zone in the crust, consisting of a shallow magma chamber and a more diffuse reservoir in the lower crust, and estimate the total magma volume in the system to be between 5 and 21 km3. This volume is two orders of magnitude larger than the amount of melt emplaced during the most recent eruption3,4 (0.1–0.2 km3). We therefore infer that such volcanic events remove only a small portion of the reservoir that they tap, which must accordingly be long-lived compared to the eruption cycle. On the basis of magma flux estimates, we estimate the crustal residence time of melt in the volcanic system to be a few hundred to a few thousand years.
Circulating endothelial progenitor cells are reduced in SLE in the absence of coronary artery calcification

Circulating endothelial progenitor cells (EPCs) are reduced in patients with systemic lupus erythematosus (SLE). A reduced number of EPCs are associated with the presence of atherosclerosis in other populations. We sought to determine whether the reduction in EPC numbers in SLE is dependent on the presence of advanced coronary artery calcification (CAC). Patients with SLE had previous coronary calcium scores which placed them in either the >75th percentile or <25th percentile for their age. Seventeen patients with SLE and 13 healthy controls (HC) were included in the study. White blood cells were stained for EPC and progenitor cell markers including CD34, CD133, and VEGFR and analyzed by flow cytometry. SLE patients had repeated coronary imaging as well as carotid ultrasound. There was no difference in age between groups. SLE patients with advanced CAC were more likely to be hypertensive, to be smokers, and to have longer disease duration than SLE patients without CAC. SLE patients without evidence of CAC had a significantly lower number of EPCs (CD34+/CD133+/VEGFR+) compared to HC (median (IQR)) 0 (0, 6.7) vs. 10.2 (5.8, 12.3) (P = 0.02). Total numbers of PCs (CD133+/CD34+) were not significantly decreased in patients with SLE ((mean ± SEM) 1,007 ± 154 vs. 824 ± 170 (P = 0.20)). No significant difference was seen in EPC number between SLE patients without CAC and those with advanced CAC. Increased carotid intima-media thickness did not correlate with CAC or EPC number in SLE patients. Reduced numbers of EPCs in SLE patients may be observed compared to HC even in the absence of CAC. Differences in measured risk factor profiles and depletion of total circulating PCs do not fully explain this finding.
AUTOMATED VARIABLE STAR CLASSIFICATION USING THE NORTHERN SKY VARIABILITY SURVEY

We have identified 4659 variable objects in the Northern Sky Variability Survey. We have classified each of these objects into one of the five variable star classes: (1) Algol/β Lyr systems including semidetached, and detached eclipsing binaries, (2) W Ursae Majoris overcontact and ellipsoidal variables, (3) long-period variables such as Cepheid and Mira-type objects, (4) RR Lyr pulsating variables, and (5) short-period variables including δ Scuti stars. All the candidates have outside of eclipse magnitudes of ~10-13. The primary classification tool is the use of Fourier coefficients combined with period information and light-curve properties to make the initial classification. Brief manual inspection was done on all light curves to remove nonperiodic variables that happened to slip through the process and to quantify any errors in the classification pipeline. We list the coordinates, period, Two Micron All Sky Survey colors, total amplitude variation, and any previous classification of the object. 548 objects previously identified as Algols in our previous paper are not included here.
Costs and Benefits of Family Involvement in Homework

Homework represents one research-based instructional strategy linked to student achievement. However, challenges abound with its current practice. This paper presents the results of three 2-year longitudinal interventions of the Teachers Involve Parents in Schoolwork (TIPS) homework program in elementary mathematics, middle school language arts, and middle school science. Each weekly standards-related TIPS assignment included specific instructions for students to involve a family partner in a discussion, interview, experiment, or other interaction. Depending on subject and grade level, TIPS students returned between 72% and 91% of TIPS activities, and families signed between 55% and 83% of TIPS assignments. TIPS students and families responded significantly more positively than controls to questions about their emotions and attitudes about the homework experience, and TIPS families and students reported higher levels of family involvement in the TIPS subject. No differences emerged in the amount of time s...
Dendritic cells are early responders to retinal injury.

The presence and activity of dendritic cells (DC) in retina is controversial, as these cells are difficult to identify in retina due to limited markers and sparse numbers. Transgenic mice that express green fluorescent protein (GFP) on the CD11c promoter to label DC allowed the visualization and quantification of retinal DC. Two retina injury models, the optic nerve crush (ONC) and light injury, were used to study their injury response. Many GFP+ DC were tightly associated with retinal ganglion cell nerve fibers following ONC, while very few microglia (GFP−CD11b+ cells) were found in close contact. The GFP+ cells were greatly elevated in the outer plexiform layer following photic injury. All of the GFP+ DC were CD11b+, suggesting a myeloid origin. In addition, the GFP+ DC upregulated expression of MHC class II after injury, while the GFP−CD11b+ microglia did not. This study shows that DC were found in the retina and that they rapidly responded to neural injuries. We propose that they are a previously overlooked population, distinct from microglia, and may be important in the injury response.
State Environmental Policies: Analyzing Green Building Mandates

This research addresses state requirements that public facilities be constructed as “green buildings” that promote environmental friendly, energy efficient, and healthy workplaces. We consider state choices to adopt green building mandates and the form of their policy enactment. In considering the way that low salience issues like green buildings get on state agendas and the circumstances under which governors decide to engage the issue, we extend William Gormley's (1986) depiction of “board room” regulatory politics. State energy agencies provide an attention-focusing role while governors behave strategically in deciding whether to issue executive orders about green buildings. This research adds to the growing understanding of states as innovators in aspects of environmental policy not normally subject to state regulation.
Survey of random neural network applications

Abstract This paper consists of a survey of various engineering applications based on the random neural network (RNN) model [Neural Computation 1(4) (1989) 502–511; 2(2) (1990) 239–247; Comptes-Rendus Acad. Sci. t. Serie II 310(2) (1990) 177–180; Applied Math. Modelling 15 (1991) 534–541; Neural Computation 5(1) (1993) 154–164], and also a summary of the recent image processing techniques such as still image compression, image enlargement, and image fusion. The advantage of the RNN model is that it is closer to biophysical reality and mathematically more tractable than standard neural methods, especially when used as a recurrent structure.
Penobscot: A new variety of potato with leafroll resistance and high solids

Penobscot is a variety of potato bred primarily for leafroll resistance by the United States Department of Agriculture and tested cooperatively in Maine and other States as part of the National Potato-Breeding Program. The tubers of Penobscot are oblong to ovate in shape with light-cream, buff skin and medium-deep eyes. In the Maine tests, yields of Penobscot compared favorably with those of Kennebec, Katahdin, and Irish Cobbler. The specific gravity values of Penobscot were relatively high and usually exceeded those of three other commercial varieties grown in Maine. Penobscot was similar to Kennebec in chipping qualities determined both after harvest and after storage at 38 F followed by reconditioning, but its French fry color index and texture were slightly less favorable than Kennebec when fried after harvest. Penobscot possesses field immunity from mild mosaic and has considerably more resistance to leafroll in the field than the standard varieties now being grown. Its favorable processing qualities, high specific gravity, and its good yielding ability, along with its disease resistance, are all characteristics that should help to make Penobscot a valuable variety for both grower and processor.
Network Firewall Dynamics and the Subsaturation Stabilization of HIV

In 2001, Friedman et al. conjectured the existence of a "firewall effect" in which individuals who are infected with HIV, but remain in a state of low infectiousness, serve to prevent the virus from spreading. To evaluate this historical conjecture, we develop a new graph-theoretic measure that quantifies the extent to which Friedman's firewall hypothesis(FH)holds in a risk network. We compute this new measure across simulated trajectories of a stochastic discrete dynamical system that models a social network of 25,000 individuals engaging in risk acts over a period of 15 years. The model's parameters are based on analyses of data collected in prior studies of the real-world risk networks of people who inject drugs (PWID) in New York City. Analysis of system trajectories reveals the structural mechanisms by which individuals with mature HIV infections tend to partition the network into homogeneous clusters (with respect to infection status) and how uninfected clusters remain relatively stable (with respect to infection status) over long stretches of time. We confirm the spontaneous emergence of network firewalls in the system and reveal their structural role in the nonspreading of HIV.
Emphysematous pyelitis presenting as an acute abdomen in an end-stage renal disease patient treated with peritoneal dialysis.

Emphysematous pyelitis is air in the renal collecting system in patients with urinary tract infections. This entity is uncommon and seen primarily in patients with diabetes mellitus. We report a case of a patient with end-stage renal disease treated with peritoneal dialysis who developed emphysematous pyelitis who presented with signs and symptoms that were more consistent with appendicitis. The spectrum of infections causing air in the urinary tract and the method by which end-stage renal disease patients are treated are discussed. Patients receiving dextrose peritoneal dialysis are at risk for emphysematous pyelonephritis, pyelitis, and cystitis.
The brittle compressive fracture of ice

Abstract The brittle compressive fracture under uniaxial loading of fresh-water, granular ice Ih has been studied. Measurements are reported of the fracture stress at temperatures from −10 to −50°C at strain rates of 10 −3 and 10 −1 s −1 for grain sizes from approximately 1 to 10 mm. Also a summary is reported of measurements by Jones et al . (unpublished) of the kinetic coefficient of friction for ice on ice at temperatures from −10 to −40°C at sliding velocities from 5 × 10 −7 m s −1 to 5 × 10 −2 ms −1 . Observations via high speed photography of internal cracking during loading are included. The strength, albeit scattered, increases with decreasing grain size, with decreasing temperature and at −10°C with decreasing strain rate. Similarly, the coefficient of friction increases with decreasing temperature and at −10°C with decreasing sliding velocity. Wing cracks were observed on some inclined cracks nucleated during loading. The results are explained in terms of the frictional crack sliding-wing crack model [as developed by Ashby and Hallam, Acta metall. 34, 497 (1986)] of compressive fracture. Finally, a simple model is presented for the transition from ductile to brittle behavior. It is based upon the competition between the building up and the relaxation of internal stresses within the vicinity of the internal cracks, and it leads to a transition strain rate which can be expressed in terms of the fracture toughness, the creep rate, the kinetic coefficient of friction and the microstructural scale of the material.
Mystery novel reveals model for educators: reflections on teaching and learning

A narrative passage from a novel is used to explicate knowledge, behaviors, and attitudes of good teachers. Emphasis is on teacher–student interactions designed to facilitate a positive educational experience. Asserted strategies and principles of good teaching are supported by recent literature.
Studies on the mechanism of 3-deazaguanine cytotoxicity in L1210-sensitive and -resistant cell lines.

3-Deazaguanine (3-DG), a purine analogue, has unusual antitumor activity against experimental mammary tumor models and a number of other solid tumors. Others have shown that mutant CHO cells deficient in hypoxanthine guanine phosphoribosyl transferase (HGPRTase) or adenine phosphoribosyl transferase (APRTase) are resistant to 3-DG. We developed a L1210 cell line resistant to 3-DG, L1210/3-DG, by subculturing the parent L1210/0 cells in the presence of increasing concentrations of 3-DG. The IC50 was 3.5 μM and 620 μM for L1210/0 and L1210/3-DG, respectively. Cytotoxicity studies proved the resistance to be stable. Examination of the baseline-specific activity of HGPRTase and APRTase showed that the former was 118-fold lower in L1210/3-DG than in L1210/0, and the latter demonstrated no difference. A 4-h treatment of the cell lines at IC50 doses showed 48% and 23% reductions in IMP dehydrogenase in L1210/0 and L1210/3-DG, respectively. The rate of de novo purine biosynthesis was studied by using [14C]formic acid. Formate flux increased 2-fold in L1210/3DG in concert with the observed deficiency of HGPRTase in the cell line. 3-DG uptake was studied with [14C]-labelled compound. The total radioactivity was 9-fold higher in L1210/0 than in L1210/3-DG at 2 h. Subsequent chromatographic separation of radioactivity showed the 3-DG and 3-deazaguanosine pools of the drug to be equal in both lines. However, 3-DG nucleotide pools at 1 min and 2 h were 2.5-fold and 16-fold lower, respectively, in L1210/3-DG than in L1210/0. 3-DG incorporation studies with radiolabelled drug demonstrated that 3-deazaguanine is incorporated in the acid-insoluble fraction of the cell. These studies conclude that HGPRTase, and not APRTase, is required for the activation of drug. Inhibition of IMP dehydrogenase is partially responsible for antitumor activity of the drug. The incorporation of drug into nucleic acids may be a major mechanism for its antitumor activity. Further studies using a cloned cDNA probe for hypoxanthine guanine phosphoribosyltransferase (HGPRT) demonstrated no change in the DNA arrangements of the L1210/3-DG cell line, and Northern blot analysis showed approximately equal expression of mRNA in both cell lines.
You can't be in my choir if you can't stand up: one journey toward inclusion

The main purpose of this study was to expand the current research model available on the inclusion of individuals with special needs in music-making. The case study was designed to provide a unique perspective on music-making in the choral environment from the perspective of the special needs individual. The rationale for conducting research stems from the philosophical desire to show both the possibilities and potential benefits of including individuals with special needs in choirs. The methodology was that of a qualitative case study interpreted through the methodological tool of phenomenology. The case study was primarily conducted through a semi-structured interview process. Follow-up interviews were conducted to help verify interpretations and conclusions and were brief in nature. In addition, a follow-up observation of an inclusion choir rehearsal took place. Grounded theory was used to arrive at an interpretation of the various data gathered from the case study: (a) interview transcriptions, (b) fi...
Convex relaxation of optimal power flow: A tutorial

This is a short survey of recent advances in the convex relaxation of the optimal power flow problem. Our focus is on understanding structural properties, especially the underlying convexity structure, of optimal power flow problems rather than different computational algorithms.
Application of a Combined Catalyst and Sorbent for Steam Reforming of Methane

The performance of a combined catalyst and sorbent material designed for reforming hydrocarbons was evaluated by reacting methane with steam at different temperatures and pressures in a reactor pac...
Dosed myofascial release in three-dimensional bioengineered tendons: effects on human fibroblast hyperplasia, hypertrophy, and cytokine secretion.

Abstract Objective The purpose of this study was to investigate potential differences of magnitudes and durations associated with dosed myofascial release (MFR) on human fibroblast proliferation, hypertrophy, and cytokine secretions. Methods Bioengineered tendons (BETs) attached to nylon mesh anchors were strained uniaxially using a vacuum pressure designed to model MFR varying in magnitudes (0%, 3%, 6%, 9%, and 12% elongation) and durations (0.5 and 1-5 minutes). Conditioned media were analyzed for cytokine secretion via protein microarray (n = 2). Bioengineered tendons were weighted and fibroblasts extracted from the BET were assessed for total cell protein and proliferation via double-stranded DNA quantification (n = 5). All data were compared by a 1-way analysis of variance with post hoc Dunnett test and Student t test. Results Changing MFR magnitude and duration did not have an effect on total fibroblast cellular protein or DNA accumulation. However, we observed a stepwise increase in BET weight with higher-magnitude MFR treatments. Longer durations of MFR resulted in progressive increase in the secretions of angiogenin, interleukin (IL)-3, IL-8, growth colony–stimulating factor, and thymus activation–regulated chemokine. Alternatively, increasing strain magnitude induced secretions of IL-1 β , monocyte chemoattractant cytokine, and regulated and normal T cell expressed and secreted chemotactic cytokine. Conclusion Cellular proliferation and hypertrophy were not significantly changed by any treatment. However, the change in total BET dry weight suggests that production of extracellular matrix protein may be up-regulated. Different MFR parameters induce secretions of a unique subset of cytokines and growth factors that can be further enhanced by increasing the magnitude and duration of treatment. If clinically translatable, these results suggest that variations to manual therapy biomechanical parameters may differentially affect physiological responses in vivo.
A rapid inexpensive quantitative general purpose densitometer and its application to one dimensional gel electrophoretograms

We describe the construction of a densitometer based on a TV camera linked to an IBM personal computer (PC) using commercially available components. We discuss some of the problems of accurate quantitative densitometry using low-cost video systems, and describe the manner in which absolute optical density values may be recorded. We describe a digital analysis routine designed to quantitate unresolved bands on noisy one-dimensional electrophoretograms.
Geometry and Structure of Multimaterial Photodetecting Fibers: a Comparative Study

We report on the influence of geometrical and structural changes on the performance of one dimensional distributed photodetecting fibers for applications in large area optoelectronic systems, remote sensing of analytes and functional fabrics.
Explorations in Neighborhood Differentiation

The cyclical interest in local units of the urban community has failed to provide cumulative knowledge about the varieties, functions and ethnic distribution of types of neighborhoods. Research in ...
Enhancement of hexobarbital-induced sleep by lysine and its metabolites.

Abstract Lysine has been shown to be metabolized in the rat brain to pipecolic acid which is a precursor of piperidine. Lysine and its proposed metabolites in this pathway were studied for the first time for their effect on the sleeping time induced by hexobarbital in the rat. Only L -lysine and D -lysine were found to prolong sleeping time significantly without toxic effect. A 3-day pretreatment with L -lysine produced an even more profound sleep prolongation. In most cases sleep enhancement was accompanied by a significant shortening of the time of sleep onset. Quantification of brain hexobarbital levels in the control and treated rats indicates that prolongation of sleeping time was not produced by inhibition of hexobarbital metabolism. The sleep prolonging effect of lysine, therefore, may be a direct action of lysine, or the metabolite(s) derived in vivo from lysine, on the central nervous system.
Wind Erodibility of Organic Soils

Intensively cropped organic soils are often subject to severe wind erosion. The objective of this study was to measure their physical wind erodibility properties. Four organic soils were collected from Florida, North Carolina, and Michigan. The organic matter content, aggregate density, dry-aggregate stability, aggregate size distribution, and soil water characteristics were measured. Trays (122 by 20 by 6 cm) were filled with field-sampled soils and sieved soils with 80% of aggregates <0.84 mm. Trays of both crusted and uncrusted soil were place in a laboratory wind tunnel and exposed to wind of various speeds. Aggregate densities ranged from 0.93 to 1.13 Mg m -3 , which is less than typical mineral soils. Dry-aggregate stability was relatively high [2.9-4.7 In(J kg -1 )]. Threshold friction velocity varied from 0.40 to 0.83 m s -1 for the field condition and from 0.27 to 0.31 m s -1 for the soil with 80% of the aggregates <0.84 mm. The aggregate abrasion coefficients ranged from 0.0006 to 0.0136 m -1 , meaning the aggregates should be moderately resistant to abrasion losses. The crust abrasion coefficients varied from 0.039 to 0.123 m -1 . Hence, a crusted soil surface should abrade more easily than a well-aggregated soil. The loose erodible material on the crusts ranged from 0.010 to 0.068 kg m -2 and varied directly with sand content and inversely with organic matter. The threshold friction velocities of organic soils were slightly higher than would be predicted for comparable mineral soils. From the results of this study, it is expected that for a given wind speed, a nearly equal mass of soil would be eroded from organic soils as from comparable mineral soil.
Morphological Specializations of the Digestive Tract of Zacryptocerus rohweri (Hymenoptera: Formicidae)

Light, scanning, and transmission electron microscopy are used to examine the morphology and ultrastructure of the peculiar digestive tract of the turtle ant, Zacryptocerus rohweri. The proventriculus is heavily sclerotized and covered with clusters of small spines. Narrow spine-lined channels converging at the opening to the midgut act as a fine filter of food; particles .12.5 µm are unable to pass through the proventriculus. In the midgut, ultrastructural study reveals bacteria among the microvilli of midgut epithelial cells. The hindgut of Z. rohweri consists of an enlarged, dark- colored pouch filled with masses of bacteria of three major morphotypes. A thick layer of circular muscle and deep infoldings of the epithelium greatly increase surface area for absorption. Newly emerged individuals appear to acquire these microorganisms by soliciting material from the abdomen tip of other older workers in the colony. Whether or not the hindgut bacteria are true symbionts is unknown; their acquisition and presence suggest that they may supplement the ants' limited, liquid diet by supplying essential amino acids and other nutrients. J. Morphol. 234:253-262, 1997. r 1997 Wiley-Liss, Inc.
Reflections on Lipoplasty: History and Personal Experience

The author presents a brief history of the development of lipoplasty in the United States over more than 30 years. The chronology includes major clinical advances, along with the author's personal experience and the role of organized plastic surgery in defining and promoting safe practices.
The cosmic far ultraviolet background

Recent progress in understanding the cosmic far-UV background is reviewed. The correlation between the far-UV background and Galactic parameters is examined, and the dust-scattered Galactic radiation is considered as the primary source of the far-UV background. The spectrum of the far-UV background is discussed along with the cosmic background from 912 to 1200 A. The extragalactic background and related exotica are addressed.
An evaluation of JPEG and JPEG 2000 irreversible compression algorithms applied to neurologic computed tomography and magnetic resonance images

We performed visual comparison of 200 head magnetic resonance (MR) and 200 head computed tomography (CT) images compressed at two levels using standard Joint Photographic Experts Group (JPEG) irreversible compression and a preliminary version of the JPEG 2000 irreversible algorithm. Blinded evaluations by neuroradiologists compared original versus either JPEG or JPEG 2000. We found that this version of JPEG 2000 did not perform as well as the current JPEG for head CTs, but for MR images, JPEG 2000 performed as well or better. Around 7∶1 compression ratio seemed to be a conservative point where there was no perceptible difference.
Influence of Model Inaccuracies on the Prediction of Dynamic System Performance

A good understanding of system dynamics is imperative to the design of any control strategy. Results of inaccurate models can lead to inefficient controls. However, the formulation of an accurate dynamic model requires high computational power and hence various simplifying assumptions are made while deriving the system equations. In order to illustrate this concept, a simple dynamic experiment of a double-pendulum is formulated and the responses obtained from the derived model and the actual model were compared. Inaccuracies of the derived model clearly showed up in the comparison. By taking into account factors, which were initially omitted for simplifying calculation, the inaccuracies observed could be minimized.Copyright © 2002 by ASME
Specificity of bacterial collagenase: studies with peptides newly synthesized using the solid-phase method.

Abstract The method of solid-phase synthesis was followed in the preparation of seven new oligopeptides which were used to study the specificity requirements of clostridiopeptidase A (EC 3.4.4.19). The newly synthesized peptides were structural and stereochemical modifications of the collagen-like sequence -Pro-X-Gly-Pro-Y-. It was shown that with the enzyme preparation used, the Y-Gly bond in sequences like -Gly-X-Y-Gly-Pro-Z- or -Gly-X-Y-Gly-Z-Pro- can be cleaved. This observed lack of specificity might be due to the presence of a collagenase with a broader specificity in the preparation utilized in this study or, alternatively, could be accounted for by an inherent property of the subunit-containing enzyme which allows the accommodation of some structural variations and shows, therefore, less specificity than originally was proposed.