Thymineless death (TLD) in bacteria has been a focus of research for decades. Nevertheless, the advances in the last 5 years, with Escherichia coli as the model organism, have been outstanding. Independent research groups have presented compelling results that establish that the initiation of chromosome replication under thymine starvation is a key element in the scenario of TLD. Here we review...

OBJECTIVE Third Location Decompression (TLD) is an activity undertaken by UK Armed Forces (UK AF) personnel at the end of an operational deployment which aims to smooth the transition between operations and returning home. We assessed whether TLD impacted upon both mental health and postdeployment readjustment. METHOD Data collected during a large cohort study was examined to identify personn...

Polymer gel dosimetry undertaken on a multislice CT scanner provides an alternative method to conventional dosimetry measurements. Polymer gel dosimeters were used to measure CT radiation doses and compared to TLD and ionization chamber measurements in different diameter phantoms. CTDI was investigated for each of these phantoms for a range of mAs (100-400 mAs), tube voltage (100-135 kV) and no...

The early history of the esoteric phenomenon of thymineless death (TLD) is recounted, from the pioneering discovery by Seymour Cohen and Hazel Barner, through my graduate studies at Yale and postdoctoral research in Copenhagen. My principal contribution was the discovery that restricted synthesis of protein and RNA permits cultures of Escherichia coli to complete their DNA replication cycles wi...

The possibility to combine the track-etched CR-39 or Makrofol detectors with charcoal to increase the detector sensitivity was shown in the last years. Special requests are necessary in the case of a personal dosimeter when the detector must be active only during working activity. Regarding the combination of charcoal with TL detectors our preliminary investigations indicate that the TLD intens...

PURPOSE Thermoluminescent dosimeters are used routinely for dosimetric measurements of photon and electron fields. However, no work has been published characterizing TLDs for use in combined photon and electron fields. This work investigates the response of TLD-100 (LiF:Mg,Ti) in mixed fields of photon and electron beam qualities. METHODS TLDs were irradiated in a 6 MV photon beam, 6 MeV elec...

TLD is a tank filled with water and serves as a dynamic vibration absorber for passive control of structures. This paper addresses the comparisons of TLD performances corresponding to different tank geometries including rectangular and conical shapes. Due to the importance of water and tank weight as a load on top of a building, volume is considered to be a constant parameter in this study. Fir...

In the present paper, we report the indigenous development of a neutron-sensitive thermoluminescent dosemeter (TLD) based on CaSO4:Dy Teflon TL disc. The study includes indigenous development of a neutron dosemeter and its response in terms of operational quantity to different energies of neutrons under various irradiation conditions. It was found that the thermal neutron sensitivity of the CaS...

When grown in thymine-free minimal synthetic medium, thyA recA mutants of Escherichia coli K12 were comparatively more resistant and thyA recBC mutants more sensitive to thymineless death (TLD) than their respective parent strains. No excessive numbers of single-strand breaks were observed in the DNA of the recBC mutant strain starved for thymine, hence the hypersensitivity for TLD in this stra...