Comparative Study of Different Drills for Bone Drilling: A Systematic Approach.

INTRODUCTION: The performance of the drilling process depends on the characteristics of the drilling equipment and surgeon's skill. To our knowledge, no research has focused on multi-parameter analysis of the dynamic behaviour of drills during the drilling process. This study aimed to characterise the physical changes and effects of different drills attached to a robotic arm during drilling of artificial bones in a standardised experimental setup. MATERIAL AND METHODS: Drilling processes using three brands of drills attached to a robotic arm were compared in terms of thrust force, vibration, noise level, speed deviation, and temperature. A standardised experimental setup was constructed, and measurement data were analysed statistically. Identical artificial bones were drilled 10 times with each drill. RESULTS: Thrust force measurements, which varied through the cortex and medulla, showed expressive differences for each drill for maximum and mean values (p<0.001). Meaningful differences were obtained for mean vibration values and noise level (p<0.001). Speed variation measurements in drilling showed conspicuous differences with confident statistics (p<0.001). Induced temperature values were measured statistically for Drill 1, Drill 2, and Drill 3 as 78.38±11.49°C, 78.11±7.79°C, and 89.77±7.79°C, respectively. CONCLUSION: Thrust force and drill bit temperature were strongly correlated for each drill. Vibration values and noise level, which also had an influential relationship, were in the acceptable range for all experiments. Both thrust force and speed deviation information could be used to detect the drill bit status in the bone while drilling.

Reduction in serum paraoxonase level in newborns with hyperbilirubinemia as a marker of oxidative stress.

OBJECTIVE: Indirect bilirubin exerts an antioxidant effect when increased mildly. This study aimed to investigate whether increased bilirubin levels lead to an oxidant effect in newborns with hyperbilirubinemia requiring phototherapy. PATIENTS AND METHODS: The study included 30 term newborn infants aged 0-7 days with indirect hyperbilirubinemia requiring phototherapy and no comorbid disease as the study group. In addition, 30 term healthy newborn infants aged 0-7 days without indirect hyperbilirubinemia were employed as a control group. Serum triglyceride, total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), serum paraoxonase (PON) levels and malondialdehyde (MDA) levels were compared between the groups. RESULTS: Serum MDA, total bilirubin, and LDL and HDL levels were significantly higher and the serum PON level was significantly lower, in the study group compared with the controls (p < 0.05). CONCLUSION: In newborns with hyperbilirubinemia requiring phototherapy, an increased bilirubin level causes oxidative stress by decreasing the level of serum PON and increasing the level of MDA.

An unexpected cause of anaphylaxis: potato.

Immediate reactions against contact to raw potato has been reported in adults with generally being in the form of an oral contact dermatitis or contact urticaria, but it may also manifest as rhinitis symptoms, wheezing or even anaphylaxis. Cooked or raw potato allergy has been rarely reported in children as some is being immediate and others being late reactions, and it usually results from ingestion. Herein, we report two cases with a background of allergic diseases developed anaphylaxis one with cooked potato and the other one with raw potato.

Pressurized H2 RF cavities in ionizing beams and magnetic fields.

A major technological challenge in building a muon cooling channel is operating rf cavities in multitesla external magnetic fields. We report the first proof-of-principle experiment of a high pressure gas-filled rf cavity for use with intense ionizing beams and strong external magnetic fields. rf power consumption by beam-induced plasma is investigated with hydrogen and deuterium gases with pressures between 20 and 100 atm and peak rf gradients between 5 and 50 MV/m. The low pressure case agrees well with an analytical model based on electron and ion mobilities. Varying concentrations of oxygen gas are investigated to remove free electrons from the cavity and reduce the rf power consumption. Measurements of the electron attachment time to oxygen and rate of ion-ion recombination are also made. Additionally, we demonstrate the operation of the gas-filled rf cavity in a solenoidal field of up to 3 T, finding no major magnetic field dependence. All these results indicate that a high pressure gas-filled cavity is a viable technology for muon ionization cooling.

Measurement of transmission efficiency for 400 MeV proton beam through collimator at Fermilab MuCool Test Area using Chromox-6 scintillation screen.

The MuCool Test Area (MTA) at Fermilab is a facility to develop the technology required for ionization cooling for a future Muon Collider and∕or Neutrino Factory. As part of this research program, feasibility studies of various types of RF cavities in a high magnetic field environment are in progress. As a unique approach, we have tested a RF cavity filled with a high pressure hydrogen gas with a 400 MeV proton beam in an external magnetic field (B = 3 T). Quantitative information about the number of protons passing through this cavity is an essential requirement of the beam test. The MTA is a flammable gas (hydrogen) hazard zone. Due to safety reasons, no active (energized) beam diagnostic instrument can be used. Moreover, when the magnetic field is on, current transformers (toroids) used for beam intensity measurements do not work due to the saturation of the ferrite material of the transformer. Based on these requirements, we have developed a passive beam diagnostic instrumentation using a combination of a Chromox-6 scintillation screen and CCD camera. This paper describes details of the beam profile and position obtained from the CCD image with B = 0 T and B = 3 T, and for high and low intensity proton beams. A comparison is made with beam size obtained from multi-wires detector. Beam transmission efficiency through a collimator with a 4 mm diameter hole is measured by the toroids and CCD image of the scintillation screen. Results show that the transmission efficiency estimated from the CCD image is consistent with the toroid measurement, which enables us to monitor the beam transmission efficiency even in a high magnetic field environment.

Analytic performance of bacteriuria and leukocyturia obtained by UriSed in culture positive urinary tract infections.

BACKGROUND: Urine analysis is one of the most common tests for assessing urinary-tract infections, which are the most frequently occurring infectious diseases in community populations. Urine culture is still the 'gold standard' for the detection of urinary tract infection, however, it is time- and labor-intensive and and has a high number of unnecessary cultures. The aim of this study was to evaluate the analytical and diagnostic performance of a new urinalysis system LabUMat with UriSed (77 Elektronika, Budapest, Hungary) in comparison to urine culture as the reference method. METHODS: By comparing the test results for 965 urine samples with quantitative urine cultures, we established cutoff criteria for the UriSed. The cut-off values by the receiver operating characteristic (ROC) curve technique, sensitivity, and specificity were calculated for bacteria (BACT) and white blood cells (WBCs). RESULTS: A bacterial cutoff value of 375/microL provided the best discrimination for community-acquired urinary tract infection, with a sensitivity of 96.5% and a specificity of 82.1% compared with 182 urine culture positive samples (AUC: 0.939). It was possible to forgo 62.6% of cultures with only 8 false-negative results. The best cut-off value for WBCs was 13/microL. When we used an algorithm in which the combination with the positivity for 85 BACT/microL and for 13 WBCs/microL count, the sensitivity and NPV improved to 99.8% and 100%, respectively, but the specificity declined from 78.8% to 52.0%. CONCLUSIONS: When screening with the UriSed for community-acquired urinary tract infection, a cut-off value of 85 bacteria/microL and 13 WBCs/microL should be adopted. Diagnostic performance of UriSed is satisfactory and use of this instrument is a reliable method for screening out a major part of the culture negative samples. It would improve the efficiency of microbiology laboratory, and unnecessary antibiotic prescriptions could be reduced.