Magneto-Optics of a Weyl Semimetal beyond the Conical Band Approximation: Case Study of TaP.

Landau-level spectroscopy, the optical analysis of electrons in materials subject to a strong magnetic field, is a versatile probe of the electronic band structure and has been successfully used in the identification of novel states of matter such as Dirac electrons, topological materials or Weyl semimetals. The latter arise from a complex interplay between crystal symmetry, spin-orbit interaction, and inverse ordering of electronic bands. Here, we report on unusual Landau-level transitions in the monopnictide TaP that decrease in energy with increasing magnetic field. We show that these transitions arise naturally at intermediate energies in time-reversal-invariant Weyl semimetals where the Weyl nodes are formed by a partially gapped nodal-loop in the band structure. We propose a simple theoretical model for electronic bands in these Weyl materials that captures the collected magneto-optical data to great extent.

Index of cardiac-electrophysiological balance in relapsing-remitting multiple sclerosis patients treated with fingolimod.

BACKGROUND: Fingolimod is indicated for the treatment of relapsing-remitting multiple sclerosis (RRMS) and also targets cardiovascular system due to receptors on cardiomyocytes. Results of previous studies are controversial for the effect of fingolimod in terms of ventricular arrhythmias. Index of cardio-electrophysiological balance (iCEB) is a risk marker for predicting malignant ventricular arrhythmia. There is no evidence on the effect of fingolimod on iCEB in patients with relapsing-remitting multiple sclerosis (RRMS). The aim of this study was to evaluate iCEB in patients with RRMS treated with fingolimod . METHODS: A total of 86 patients with RRMS treated with fingolimod were included in the study. All patients underwent a standard 12-lead surface electrocardiogram at initiation of treatment and 6 h after treatment. Heart rate, RR interval, QRS duration, QT, QTc (heart rate corrected QT), T wave peak-to-end (Tp-e) interval, Tp-e/QT, Tp-e/QTc, iCEB (QT/QRS) and iCEBc (QTc/QRS) ratios were calculated from the electrocardiogram. QT correction for heart rate was performed using both the Bazett and Fridericia formulas. Pre-treatment and post-treatment values were compared. RESULTS: Heart rate was significantly lower after fingolimod treatment (p< 0.001). While the post-treatment values of RR and QT intervals were significantly longer (p< 0.001) and post-treatment iCEB was higher (median [Q1-Q3], 4.23 [3.95-4.50] vs 4.53 [4.18-5.14]; p< 0.001), it was found that there was no statistically significant change in iCEB and other study parameters derived using QT after correcting for heart rate using both of two formulas. CONCLUSIONS: In this study, it was found that fingolimod did not statistically significantly change any of the heart rate-corrected ventricular repolarization parameters, including iCEBc, and it is safe in terms of ventricular arrhythmia.

Geographic Distribution of Multiple Arteries and Veins of 878 Kidney Donors From a Transplant Center in Turkey.

AIM: The diagnosis and management of multiple renal arteries and veins have gained importance with the increasing number of kidney transplantations and improved techniques in interventional radiology and vascular reconstructions. The aim of this study is to define and to detect the rate of multiple renal arteries and veins in our living kidney transplant donors coming from all parts of our country. METHODS: Abdominal computed tomography angiogram findings of 878 kidney transplant donors were analyzed. The presence and the distribution of multiple renal arteries and veins in donors coming from 7 geographic regions in Turkey were noted. RESULTS: The presence of multiple renal arteries was observed in 34% (48/141) of patients in the Marmara Region, 36.7% (79/215) of patients in the Black Sea Region, 37.2% (64/172) of patients in the Central Anatolia Region and 36.1% (30/83) of patients in the Southeastern Anatolia Region. The highest incidences of multiple renal arteries were observed in the Mediterranean and Aegean regions, affecting 40% (32/80) and 41.9% (26/62) of patients, respectively, while East Anatolia was found to have the lowest incidence, affecting 28% (35/125) of patients. The incidence of multiple renal veins also varied across regions. The highest incidence was observed in the Central Anatolia Region, where 23.3% (40/172) of patients were affected; the lowest was seen in the Aegean Region, where 11.3% (7/62) of patients were affected. In Turkey as a whole, 35.8% (314/878) of patients presented with multiple renal arteries, while the rate of multiple renal veins was found to be 19% (167/878) among our donors. CONCLUSIONS: As 80% of the kidney transplantations performed in Turkey involve living donors, we think it will be useful to have knowledge of not only the presence of multiple renal arteries and veins, but also the distribution of this feature throughout the different regions of the country.

Repair of zone 2 flexor pollicis longus lacerations in children.

We reviewed seven thumbs in six children at a mean of 43 months after repair of the flexor pollicis longus tendon in zone 2. Using the classification of Buck-Gramcko et al. (1976) the results were excellent in six and good in one.

Results of ray resection and amputation for ring avulsion injuries at the proximal interphalangeal joint.

We investigated the long-term functional results of ray resection (14 cases) and amputation (nine cases) for ring avulsion injuries of ring finger which could not be replanted or underwent failed replantation. The mean follow-up was 37 (range, 24-63) months in the ray resection group and 32 (range, 24-40) months in the amputation group. Grip strength, key pinch strength, chuck pinch strength, hand circumference and palmar volume were decreased in the ray resection group but only grip strength and pulp pinch strength were significantly decreased in the amputation group. These results suggest that ray resection should be avoided in patients with occupations that need strong key and chuck pinch functions.

Evaluation of the improvement of sensibility after primary median nerve repair at the wrist.

In the Istanbul Hand Surgery and Microsurgery Centre, between 1991-1996, 28 out of 54 patients who had clean-cut median nerve laceration at the wrist level were evaluated in a detailed manner regarding the improvement of sensibility following primary repair. Semmes-Weinstein monofilament and vibration tests form the group of threshold tests, and static and dynamic two-point discrimination tests and the Moberg pick-up test form the group of functional tests which were applied to the patients. Follow-up was from 1 to 5 years. Moreover, subjective findings such as cold intolerance, pain, and paraesthesia were also evaluated. All the results obtained were evaluated in relation to the SO-S4 sensibility improvement criterion which Waylett-Rendall recommended. The following results were obtained: S4 in 35.7% of the patients, S3+ in 28.5%, S3 in 14.2%, S2+ in 7.14%, S2 in 10.7%, and S1 in 3.5%. In our opinion the most important reason for the high rate of success was the fact that we worked with a highly selective group of patients and the fact that there was a high rate of young patients in this group (21.4% of them were under the age of 15). It was observed that there was a significant correlation between age and functional sensibility improvement (P = 0.04). Moreover, when we observed the relation between age and Semmes-Weinstein monofilament, static two-point discrimination, and dynamic two-point discrimination tests, it was seen that age had a significant correlation with each of the parameters (r = 0.61, P = 0.001; r = 0.58, P = 0.002; r = 0.57, P = 0.002). There was a clear decline in the intensity of the paraesthesia in S3+ and S4 group (X2 = 4.7, P = 0.02) and in these groups the period of Moberg pick-up test was meaningfully short (P < 0.05).