564 research outputs found
Sensitivity Curves for Asymmetric Trimming Hinge Estimators
Robust estimators have been developed and tested for symmetric distributions via simulation studies. The primary objective was to show that they are more efficient than the sample mean when used in conjunction with asymmetric distributions. Little attention has been given to how they perform on data that are from asymmetric distributions, or from distributions that have inherent anomalies (messy data). Thus, the behavior of hinge estimators using sensitivity curve are examined
Standardized Laparoscopic Intracorporeal Right Colectomy for Cancer: Short-Term Outcome in 111 Unselected Patients
Purpose This study was designed to evaluate the impact of a standardized laparoscopic intracorporeal right colectomy on the short-term outcome of patients with neoplasia. Methods Consecutive patients with histologically proven right colon neoplasia underwent a standardized laparoscopic intracorporeal right colectomy with medial to lateral approach encompassing ten sequential steps: 1) ligation of ileocolic vessels, 2) identification of right ureter, 3) dissection along superior mesenteric vein, 4) division of omentum, 5) division of right branch of middle colic vessels, 6) transection of transverse colon, 7) mobilization of right colon, 8) transection of terminal ileum, 9) ileocolic anastomosis, 10) delivery of specimen. Values were medians (ranges). Results From July 2002 to June 2005, 111 laparoscopic intracorporeal right colectomies were attempted with a 5.4 percent conversion rate. There were 57 women and 54 men, aged 64.9 (range, 40â85) years, with body mass index of 33 (range, 20â43), American Society of Anesthesiology score of 2 (range, 2â4), 36.9 percent comorbidities, and 37.8 percent previous abdominal surgery. The indication for surgery was cancer in 109 patients. Operative time was 120 (range, 80â185) minutes. Estimated blood loss was 69 (range, 50â600) ml. Overall length of skin incisions was 66 (range, 60â66) mm; 29 (range, 2â41) lymph nodes were harvested. Length of stay was four (range, 2â30) days. Complication rate was 4.5 percent. Conclusions A standardized laparoscopic intracorporeal right colectomy resulted in a favorable short-term outcome in unselected patients with neoplasia of the right colon
The absolutely continuous spectrum of one-dimensional Schr"odinger operators
This paper deals with general structural properties of one-dimensional
Schr"odinger operators with some absolutely continuous spectrum. The basic
result says that the omega limit points of the potential under the shift map
are reflectionless on the support of the absolutely continuous part of the
spectral measure. This implies an Oracle Theorem for such potentials and
Denisov-Rakhmanov type theorems.
In the discrete case, for Jacobi operators, these issues were discussed in my
recent paper [19]. The treatment of the continuous case in the present paper
depends on the same basic ideas.Comment: references added; a few very minor change
Active control of qubit-qubit entanglement evolution
In this work, we propose a scheme to design the time evolution of the entropy
of entanglement between two qubits. It is shown an explicit accurate solution
for the inverse problem of determining the time dependence of the coupling
constant from a user-defined dynamical entanglement function. Such an active
control of entanglement can be implemented in many different physical
implementations of coupled qubits, and we briefly comment on the use of
interacting flux qubits.Comment: Author added, Expanded version, 10 figure
Molecular materials from 1,3,2-dithiazolyls. Solid-state structures and magnetic properties of 2,3-naphthalene and quinoxaline derivatives
Hearing loss and satisfaction with healthcare: An unexplored relationship
Patient healthcare satisfaction has become increasingly important since Medicareâs introduction of the Hospital Care Quality Information from the Consumer Perspective (HCAHPS) survey. Greater satisfaction is associated with important healthcare outcomes including lower risk of 30-day readmission
SchrĂśdinger operators with δ and δâ˛-potentials supported on hypersurfaces
Self-adjoint SchrĂśdinger operators with δ and δâ˛-potentials supported on a smooth compact hypersurface are defined explicitly via boundary conditions. The spectral properties of these operators are investigated, regularity results on the functions in their domains are obtained, and analogues of the BirmanâSchwinger principle and a variant of Kreinâs formula are shown. Furthermore, Schattenâvon Neumann type estimates for the differences of the powers of the resolvents of the SchrĂśdinger operators with δ and δâ˛-potentials, and the SchrĂśdinger operator without a singular interaction are proved. An immediate consequence of these estimates is the existence and completeness of the wave operators of the corresponding scattering systems, as well as the unitary equivalence of the absolutely continuous parts of the singularly perturbed and unperturbed SchrĂśdinger operators. In the proofs of our main theorems we make use of abstract methods from extension theory of symmetric operators, some algebraic considerations and results on elliptic regularity
Scaling anomaly in cosmic string background
We show that the classical scale symmetry of a particle moving in cosmic
string background is broken upon inequivalent quantization of the classical
system, leading to anomaly. The consequence of this anomaly is the formation of
single bound state in the coupling interval \gamma\in(-1,1). The inequivalent
quantization is characterized by a 1-parameter family of self-adjoint extension
parameter \omega. It has been conjectured that the formation of loosely bound
state in cosmic string background may lead to the so called anomalous
scattering cross section for the particles, which is usually seen in molecular
physics.Comment: 4 pages,1 figur
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