A fast high-order method to calculate wakefield forces in an electron beam

In this paper we report on a high-order fast method to numerically calculate wakefield forces in an electron beam given a wake function model. This method is based on a Newton-Cotes quadrature rule for integral approximation and an FFT method for discrete summation that results in an $O(Nlog(N))$ computational cost, where $N$ is the number of grid points. Using the Simpson quadrature rule with an accuracy of $O(h^4)$, where $h$ is the grid size, we present numerical calculation of the wakefields from a resonator wake function model and from a one-dimensional coherent synchrotron radiation (CSR) wake model. Besides the fast speed and high numerical accuracy, the calculation using the direct line density instead of the first derivative of the line density avoids numerical filtering of the electron density function for computing the CSR wakefield force

TAM or VFM? Which Model Matches How People Ascribe Actually Value?

The IT community has a long history of developing theory to explain when people will change their behaviors to adopt new technology systems. Two current technology adoption theories, the Technology Adoption Model and the Value Frequency Model, draw from different groups of referent theory: Reasons Theories (RTs) and Expectancy Value Theories (EVTs). RTs and EVTs make different assumptions about how people form attitudes toward behavioral changes (i.e., to adopt or not). Having a better understanding of how people make judgments that affect their behavioral choices could help guide the choice of referent theory when developing new IT theory. This study examined how people responded to attitude-shaping scenarios as a way to gain insight into the assumptions that could be guiding their choices. Their responses indicated a tendency to assign values in ways consistent with the assumptions and processes articulated in EVTs

Exchange biased anomalous Hall effect driven by frustration in a magnetic kagome lattice.

Co[Formula: see text]Sn[Formula: see text]S[Formula: see text] is a ferromagnetic Weyl semimetal that has been the subject of intense scientific interest due to its large anomalous Hall effect. We show that the coupling of this material's topological properties to its magnetic texture leads to a strongly exchange biased anomalous Hall effect. We argue that this is likely caused by the coexistence of ferromagnetism and geometric frustration intrinsic to the kagome network of magnetic ions, giving rise to spin-glass behavior and an exchange bias

Mortality of Cranes (Gruidae) Associated with Powerlines over a Major Roost on the Platte River, Nebraska

Two 69-kilovolt powerlines spanning the Platte River in south central Nebraska are suspected to cause substantial mortality to sandhill cranes (Grus canadensis) and pose a threat to endangered whooping cranes (G. americana) that roost overnight on the river during spring and fall migrations. Most studies of crane collisions with powerlines in the region have focused on counts of carcasses away from night roosts on the river and none have accounted for potential biases in detecting carcasses. We found 61 carcasses of sandhill cranes below over-river segments of the two powerlines during 4 March to 7 April 2006 and 90 such carcasses between 5 March and 13 April 2007. In 2007 we estimated the number of carcasses undetected in our surveys due to removal by scavengers, loss to downstream flow, and observer oversight. We estimated between 165 and 219 sandhill cranes were killed by the two powerlines during spring 2007. These cnlculations exclude mortalities from individuals injured by powerline collisions and dying elsewhere, as well as those killed before or after our 5 March to 13 April survey period. We detected no evidence of mortality for whooping cranes during our surveys. Our results corroborate anecdotal evidence of signficant sandhill crane mortality each spring due to collisions with above-ground powerlines at this major night roost. Collisions by sandhill cranes will continue and collisions by Whooping cranes seem likely unless an effective means of averting birds from powerlines is implemented at this site

Progressive Wound Necrosis Associated With Postoperative Thrombocytosis in Mastectomy and Immediate Breast Reconstruction Surgery: Report of a Case

A 37-year-old who underwent splenectomy for motor vehicle accident-related injuries was diagnosed with stage IIA carcinoma of left breast 12 years later. She underwent bilateral mastectomy and bilateral immediate unipedicle TRAM flap reconstruction. Her preoperative platelet counts ranged from 332 to 424 K/cmm. Intraoperative fluorescein confirmed mastectomy flap viability. On postoperative day 1, platelet count was 374 K/cmm and all suture lines appeared benign. The patient was discharged 3 days later with healthy appearing tram flaps and slight epidermolysis in the abdominal region. Over the next 2 weeks, both the mastectomy flaps and the abdominal region underwent progressive necrosis as the platelet count increased to 1390 K/cmm. Aspirin therapy was instituted at this time. The TRAM flaps remained completely viable. Eighteen days later, the patient required wound debridement with secondary closure of the breast wounds. Platelet count peaked at 1689 K/cmm 2 days later (postoperative day 38). The wounds deteriorated again and were managed conservatively. Two months after mastectomy, the first area of spontaneous healing was documented (platelet count 758 K/cmm). Ultimately, wounds healed as platelet count reached its preoperative baseline. We hypothesize that an abnormal secondary thrombocytosis at subdermal plexus level caused problematic healing in this patient's mastectomy and abdominal flaps