Measurement of the Electromagnetic Field in Dentistry

The aim of this study was to measure the magnetic field in dentistry together with simultaneous substraction of direct ground component of the magnetic field. The research instrument used to measure the power of the magnetic field was of our own design. It measures the magnetic field by the Hall sensor that is powered with 5 to 10 V and is integrated in one chip together with preamplifier. The sensor output is differential (Q1-Q2) and proportionate to measurement values of magnetic induction. As the values of alternate fields in a laboratory setting are small the differential output voltage should be increased by about 100 times. Our study samples consisted of instruments currently available in dentistry: halogen lamps, polymerizing lamps, amalgam mixers, micromotors and dental chairs. On the basis of our study results and statistical analysis the following conclusions are made magnetic field spreads through space in ISOTROPIC manner. The greatest frequency obtained at the smallest distance was 100 kHz. The sensitivity of the measurement instrument was 0.0001 μT and the majority of instruments produce magnetic radiation higher than 4o G. The power of the magnetic field decreases with increasing distance from the source. The investigated instruments produce a relatively mild magnetic field. The instruments with stronger magnetic fields are located far enough from the persons on whom they act. The newly produced instrument acts on their environment by smaller magnetic fields

Vitrification versus controlled-rate freezing in cryopreservation of human ovarian tissue

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Measurement of Magnetic Field in Dentistry

The principal objective was to measure the magnetic fields occurring in dental surgeries at simultaneous subtraction of direct ground component of the magnetic field. A specifically designed instrument with the Hall probe was used for the measurement. It consisted of two amplifiers and a low frequency filter. Its task was to measure mean square values of the field (RMS) dependent on the position in space. Qualitative and quantitative analyses of the investigated variables enabled making conclusions about the magnetic fields in dental surgeries. A number of studies have shown that many dental instruments produce radiation with magnetic field higher than 40 G, at a significant decrease in power of the magnetic field with increasing distance from the source. It has also been reported that instruments of older generations produce stronger magnetic fields than do the new ones

The Role of Parvalbumin-positive Interneurons in Auditory Steady-State Response Deficits in Schizophrenia

© The Author(s) 2019. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.Despite an increasing body of evidence demonstrating subcellular alterations in parvalbumin-positive (PV+) interneurons in schizophrenia, their functional consequences remain elusive. Since PV+ interneurons are involved in the generation of fast cortical rhythms, these changes have been hypothesized to contribute to well-established alterations of beta and gamma range oscillations in patients suffering from schizophrenia. However, the precise role of these alterations and the role of different subtypes of PV+ interneurons is still unclear. Here we used a computational model of auditory steady-state response (ASSR) deficits in schizophrenia. We investigated the differential effects of decelerated synaptic dynamics, caused by subcellular alterations at two subtypes of PV+ interneurons: basket cells and chandelier cells. Our simulations suggest that subcellular alterations at basket cell synapses rather than chandelier cell synapses are the main contributor to these deficits. Particularly, basket cells might serve as target for innovative therapeutic interventions aiming at reversing the oscillatory deficits.Peer reviewe

Relationship Between Osteonecrosis of the Jaw and Bisphosphonate Treatment

Terapija bisfosfonatima i njezina etiopatogenetska povezanost s aseptičkom osteonekrozom čeljusti važan je javnozdravstveni problem današnjice. Svrha je rada pregledom suvremene znanstvene literature utvrditi posljedice višestrukog djelovanja bisfosfonata (antiosteoklastična aktivnost, citotoksičnost na meka i koštana tkiva, antiangiogeneza, genski čimbenici, poremećena ravnoteža između osteoklasta i osteoblasta). Terapija bisfosfonatima jedan je od najčešćih uzroka razvoja osteonekroze čeljusti. Epidemiološki podaci pokazuju da se javlja u bolesnika koji su uzimali jedan ili kombinanciju nitrogenih bisfosfonata. Najvažniji čimbenici rizika za ovu nuspojavu su vrsta bisfosfonata (napose visokopotentni pamidronat i zoledronat koji se daju intravenski), njihova doza i duljina medikacije te vrsta bolesti zbog koje se propisuje terapija. Pojava osteonekroze čeljusti zabilježena je uglavnom u onkoloških bolesnika i u samo 5 % bolesnika s osteoporozom koji su liječeni bisfosfonatima. U patogenezi osteonekroze povezane s bisfosfonatima važno je, sa stajališta dentalnomedicinske prakse, dobro opće oralno zdravlje jer se osteonekroza javlja napose nakon prethodnoga parodontološkog i oralnokirurškog zahvata.Bisphosphonate treatment and its aetiopathogenic association with aseptic osteonecrosis of the jaw is one of the more prominent public health issues today. The aim of this review is to see into the mechanisms of bisphosphonate effects on bones described in literature (anti-osteoclastic activity, cytotoxicity, antiangiogenesis, genetic factors, and imbalance between osteoclasts and osteoblasts). Bisphosphonate treatment is the dominant cause of jaw necrosis. Epidemiological data show an exclusive incidence of osteonecrosis of the jaw in patients who took one or a combination of nitrogen-containing bisphosphonates. Risk factors vary by the bisphosphonate potency (particularly risky are the highly potent pamidronate and zoledronate, which are given intravenously), dosage, duration of treatment, and the illness. Jaw necrosis is most common in oncology patients, and only 5 % in patients with osteoporosis. From a dental-medical point of view, a good oral health is important because osteonecrosis often appears after a periodontal or oral surgical procedure

Field Study of Transit Time of Water and Tracers Through a Soil Liner

HWRIC Project 88-04