Search for Lepton Number and Flavor Violation in K

Searches for the lepton number violating K^{+}→π^{-}µ^{+}e^{+} decay and the lepton flavor violating K^{+}→π^{+}µ^{-}e^{+} and π^{0}→µ^{-}e^{+} decays are reported using data collected by the NA62 experiment at CERN in 2017-2018. No evidence for these decays is found and upper limits of the branching ratios are obtained at 90% confidence level: B(K^{+}→π^{-}µ^{+}e^{+})<4.2×10^{-11}, B(K^{+}→π^{+}µ^{-}e^{+})<6.6×10^{-11} and B(π^{0}→µ^{-}e^{+})<3.2×10^{-10}. These results improve by 1 order of magnitude over previous results for these decay modes.

Predictions for Higgs and supersymmetry spectra from SO(10) Yukawa unification with mu > 0.

We use t, b, tau Yukawa unification to constrain supersymmetry parameter space. We find a narrow region survives for mu>0 (suggested by b-->sgamma and the anomalous magnetic moment of the muon) with A0 approximately -1.9m(16), m(10) approximately 1.4m(16), m(16) approximately 1200-3000 GeV and muM(1/2) approximately 100-500 GeV. Demanding Yukawa unification thus makes definite predictions for Higgs and sparticle masses.

Glia-axon interactions and the regulation of the extracellular K+ in the peripheral nerve.

Changes in membrane potential of both axons and Schwann cells were measured simultaneously during electrical activity and during the period of recovery in the rabbit vagus nerve by the use of the sucrose-gap apparatus. During low-frequency stimulation (0.5-1 Hz) the preparation developed a ouabain-sensitive hyperpolarization. This hyperpolarization increased when the inwardly rectifying K+ channels in Schwann cells were blocked with Ba2+, indicating that the hyperpolarization was generated by the electrogenic glial Na(+)-K+ pump. During trains at higher frequencies (15 Hz), the preparation depolarized, but after cessation of the stimulation it developed a posttetanic hyperpolarization (PTH). The PTH was also ouabain-sensitive and was strongly enhanced by Cs+ which is known to block the hyperpolarization-activated inward current (Ih) in axons but not in glial cells. These results show that the PTH reflects mainly the axonal electrogenic pump. Our results indicate that during activity the K+ released from the firing axons is removed from the extracellular space by Schwann cells and that after cessation of the stimulation the K+ surplus returns from Schwann cells back to axons. Both the glial and axonal K+ uptake is mediated by successive activation of the glial and axonal Na(+)-K+ pump. The nature of the signalling mechanisms that control the pumping rates of the respective pumps remain unknown.

[The effect of gender on prevalence and survival in thyroid carcinoma]. / Vliv pohlaví na prevalenci a prezití karcinomu stítné zlázy.

Based on their own experience with a large group of patients with thyroid cancers, the authors confirm the higher prevalence of differentiated thyroid cancers both papillary and follicular (1 : 3,5) in females, while the differences in anaplastic and medullary cancers are much less prominent. Survival of females in univariate studies is much higher in both papillary and follicular cancers compared to males, in multivariate studies these differences lose their significance and only in papillary cancers under the age of 40 years at diagnosis and in a subgroup of papillofollicular cancers the differences retain their significance. The authors therefore deduce that differences found in univariate studies are significantly influenced by other factors such as age at the diagnosis and the spread of disease at the diagnosis.

Positive thyroid cancer scintigraphy using technetium-99m methoxyisobutylisonitrile.

The aim of the study was to evaluate the possibility of detecting thyroid cancer recurrences without the need for withdrawal of thyroid suppressive treatment. Upper-body or whole-body scintigraphy was performed in a group of 200 patients evaluated for differentiated thyroid cancers in 1993 and 1994 using technetium-99m sestamibi. Scans were performed 20-30min following i.v. administration of 500MBq of 99mTc-methoxyisobutylisonitrile (MIBI). Bone and lung metastases were detected with very high sensitivity and specificity, with a very high predictive value of negative results and a somewhat lower predictive value of positive results. The sensitivity and specificity of findings in the neck were lower but the predictive value of negative results was high. Whole-body scans with 99mTc-MIBI are a useful tool in the follow-up of patients with differentiated thyroid cancer, for the detection of distant metastatic lesions.

Positive thyroid cancer scintigraphy using 99Tcm-tetrofosmin (Myoview): a preliminary report.

99Tcm-tetrofosmin imaging was performed in 23 thyroid cancer patients and compared with whole-body 131I scans, neck ultrasonography and plasma thyroglobulin levels. Of 22 patients with differentiated thyroid cancer, 8 showed identical images on 131I scan and tetrofosmin; 1 patient with medullary cancer had identical images with 99Tcm-DMSA and 99Tcm-tetrofosmin, the findings being confirmed by sonography. The potential usefulness of 99Tcm-tetrofosmin imaging in the follow-up of thyroid cancers is discussed.

Urinary tract diseases in adolescence: a radiological and clinical view.

A total of 2,003 adolescent in-patients aged 14-19 years were studied. Of these 801 (40 per cent) were found to have urinary tract disease. In 224 patients (28 per cent) a previously undetected urinary tract anomaly was diagnosed: this number including 59 per cent of girls and 41 per cent of boys. This is the first analysis showing such a high frequency of urinary tract anomalies in clinical and radiological investigations during the period of adolescence. Of particular importance are minor anomalies, in so far as these are responsible for disorders to the flow of urine. It is thought that urinary tract anomalies manifest themselves in adolescence because of increased stress and a different pattern of life, as compared with that in the preceding era of childhood. The present paper shows the cardinal importance of radiological examination and of the radiologist's role in evaluating the dynamics of the process and the prognosis of the disease and, in helping to assess the future potential for physical stress in either work or sport.