1,668 research outputs found
A Storage-Efficient and Robust Private Information Retrieval Scheme Allowing Few Servers
Since the concept of locally decodable codes was introduced by Katz and
Trevisan in 2000, it is well-known that information the-oretically secure
private information retrieval schemes can be built using locally decodable
codes. In this paper, we construct a Byzantine ro-bust PIR scheme using the
multiplicity codes introduced by Kopparty et al. Our main contributions are on
the one hand to avoid full replica-tion of the database on each server; this
significantly reduces the global redundancy. On the other hand, to have a much
lower locality in the PIR context than in the LDC context. This shows that
there exists two different notions: LDC-locality and PIR-locality. This is made
possible by exploiting geometric properties of multiplicity codes
OAO-3 end of mission tests report
Twelve engineering type tests were performed on several subsystems and experiment(s) of the OAO 3 spacecraft near its end of mission. The systems tested include: Princeton experiment package (PEP), fine error system guidance, inertial reference unit, star trackers, heat pipes, thermal control coatings, command and data handling, solar array; batteries, and onboard processor/power boost regulator. Generally, the systems performed well for the 8 1/2 years life of OAO 3, although some degradation was noted in the sensitivity of PEP and in the absorptivity of the skin coatings. Battery life was prolonged during the life of the mission in large part by carefully monitoring the charge-discharge cycle with careful attention not to overcharge
Carvedilol alone or in combination with digoxin for the management of atrial fibrillation in patients with heart failure?
AbstractObjectivesThis study examined the relative merits of digoxin, carvedilol, and their combination for the management of patients with atrial fibrillation (AF) and heart failure (HF).BackgroundIn patients with AF and HF, both digoxin and beta-blockers reduce the ventricular rate, and both may improve symptoms, but only beta-blockers have been shown to improve prognosis. If combined therapy is not superior to beta-blockers alone, treatment of patients with HF and AF could be simplified by stopping digoxin.MethodsWe enrolled 47 patients (29 males; mean age 68 years) with persistent AF and HF (mean left ventricular ejection fraction [LVEF] 24%) in a randomized, double-blinded, placebo-controlled study. In the first phase of the study, digoxin was compared with the combination of digoxin and carvedilol (four months). In the second phase, digoxin was withdrawn in a double-blinded manner in the carvedilol-treated arm, thus allowing a comparison between digoxin and carvedilol (six months). Investigations were undertaken at baseline and at the end of each phase.ResultsCompared with digoxin alone, combination therapy lowered the ventricular rate on 24-h ambulatory electrocardiographic monitoring (p < 0.0001) and during submaximal exercise (p < 0.05), whereas LVEF (p < 0.05) and symptom score (p < 0.05) improved. In phase 2, there was no significant difference between digoxin alone and carvedilol alone in any variable. The mean ventricular rate rose and LVEF fell when patients switched from combination therapy to carvedilol alone. Six-minute walk distance was not significantly influenced by any therapy.ConclusionsThe combination of carvedilol and digoxin appears generally superior to either carvedilol or digoxin alone in the management of AF in patients with HF
Will the Scottish Cancer Target for the year 2000 be met? The use of cancer registration and death records to predict future cancer incidence and mortality in Scotland.
Cancer mortality data reflect disease incidence and the effectiveness of treatment. Incidence data, however, reflect the burden of disease in the population and indicate the need for prevention measures, diagnostic services and cancer treatment facilities. Monitoring of targets mandates that both be considered. The Scottish Cancer Target, established in 1991, proposed that a reduction of 15% in mortality from cancer in the under-65s should be achieved between 1986 and 2000. Each year in Scotland approximately 8300 persons under 65 are diagnosed with cancer and 4500 die from the disease. The most common malignancies, in terms of both incident cases and deaths, in the under-65s, are lung and large bowel cancer in males, and breast, large bowel and lung cancer in females. A decrease of 6% in the number of cancer cases diagnosed in males under 65 is predicted between 1986 and 2000, whereas the number of cases in females in the year 2000 is expected to remain at the 1986 level. In contrast, substantial reductions in mortality are expected for both sexes: 17% and 25% in males and females respectively. Demographic changes will influence the numbers of cancer cases and deaths in the Scottish population in the year 2000. However, long-term trends in the major risk factors, such as smoking, are likely to be the most important determinants of the future cancer burden
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Triple stimulation (TriStim) before bilateral oophorectomy in a young woman with ovarian cancer: a case report and review of the literature
Background
Double ovarian stimulation (DuoStim) involves two rounds of controlled ovarian stimulation (COS) and oocyte retrieval in immediate succession. It represents a promising approach to increase oocyte yield for patients with diminished ovarian reserve or those with limited time before fertility-threatening oncologic treatment. We report the case of a 31-year-old woman with Stage IC endometrioid ovarian cancer who underwent a triple stimulation or “TriStim,” completing three rounds of COS and oocyte retrieval within 42 days prior to bilateral salpingo-oophorectomy.
Case presentation
A 31 year old nulligravid woman presented for fertility preservation counseling following a bilateral ovarian cystectomy that revealed Stage IC endometroid adenocarcinoma arising within endometrioid borderline tumors. The patient was counseled for bilateral salpingo-oophorectomy, lymph node dissection, and omentectomy followed by three cycles of carboplatin/paclitaxel. Prior to this, all within six weeks, the patient underwent three rounds of controlled ovarian stimulation using an antagonist protocol and human chorionic gonadotropin (hCG) trigger, resulting in vitrification of nine two-pronuclear zygotes (2PN), after which definitive surgery was performed.
Conclusions
Advantages of DuoStim procedures are increasingly recognized, especially for oncology patients with limited time before potentially sterilizing cancer treatment. To our knowledge, this is the first report of a triple stimulation (“TriStim”). Our case highlights that triple stimulation is a viable option for patients needing urgent fertility preservation in order to maximize egg and embryo yield within a limited time period
Mast cells in human periodontal disease
Recently, mast cells have been shown to produce cytokines which can direct the development of T-cell subsets. The aim of the present study was to determine the relationship between mast cells and the Th1/Th2 response in human periodontal disease. Tryptase+ mast cell numbers were decreased in chronic periodontitis tissues compared with healthy/gingivitis lesions. Lower numbers of c-kit+ cells, which remained constant regardless of clinical status, indicate that there may be no increased migration of mast cells into periodontal disease lesions. While there were no differences in IgG2+ or IgG4+ cell numbers in healthy/gingivitis samples, there was an increase in IgG4+ cells compared with IgG2+ cells in periodontitis lesions, numbers increasing with disease severity. This suggests a predominance of Th2 cells in periodontitis, although mast cells may not be the source of Th2-inducing cytokines
Jellyfish and Fish Solve the Challenges of Turning Dynamics Similarly to Achieve High Maneuverability
Turning maneuvers by aquatic animals are essential for fundamental life functions such as finding food or mates while avoiding predation. However, turning requires resolution of a fundamental dilemma based in rotational mechanics: the force powering a turn (torque) is favored by an expanded body configuration that maximizes lever arm length, yet minimizing the resistance to a turn (the moment of inertia) is favored by a contracted body configuration. How do animals balance these opposing demands? Here, we directly measure instantaneous forces along the bodies of two animal models—the radially symmetric Aurelia aurita jellyfish, and the bilaterally symmetric Danio rerio zebrafish—to evaluate their turning dynamics. Both began turns with a small, rapid shift in body kinematics that preceded major axial rotation. Although small in absolute magnitude, the high fluid accelerations achieved by these initial motions generated powerful pressure gradients that maximized torque at the start of a turn. This pattern allows these animals to initially maximize torque production before major body curvature changes. Both animals then subsequently minimized the moment of inertia, and hence resistance to axial rotation, by body bending. This sequential solution provides insight into the advantages of re-arranging mass by bending during routine swimming turns
The Lantern Vol. 6, No. 3, June 1938
• Editorial • A Senior Muses • Affinity • From Darkness Into Light • Just an Old Bell! • Memories of a Friend • To a Small Animal as it Passes • The Sky and I • Between the Mountain and the River • Solace • Three Little Islands Far From Home • Beachcomberhttps://digitalcommons.ursinus.edu/lantern/1011/thumbnail.jp
Nonlinear interaction of charged particles with a free electron gas beyond the random-phase approximation
A nonlinear description of the interaction of charged particles penetrating a
solid has become of basic importance in the interpretation of a variety of
physical phenomena. Here we develop a many-body theoretical approach to the
quadratic decay rate, energy loss, and wake potential of charged particles
moving in an interacting free electron gas. Explicit expressions for these
quantities are obtained either within the random-phase approximation (RPA) or
with full inclusion of short-range exchange and correlation effects. The Z^3
correction to the energy loss of ions is evaluated beyond RPA, in the limit of
low velocities.Comment: 5 pages, 2 figures To appear in Phys. Rev.
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