Standby Position Research Articles

A two-step mechanism controls the timing of behaviour leading to emergence from soil in adult males of the scarab beetle Dasylepida ishigakiensis

Adults of the white grub beetle Dasylepida ishigakiensis Niijima et Kinoshita (Coleoptera: Scarabaeidae) emerge from the soil around dusk for mating on subtropical islands. The present study examines the factors controlling the emergence of males in the laboratory. There are two steps involved. Standby behaviour (i.e. insect head appears at the soil surface) can be observed for several hours before the beetles actually emerge for mating. The standby behaviour is facilitated by warm conditions, although the proportion of standby individuals is influenced not only by the temperature on that day, but also by that on the previous day. Experiments in which beetles are exposed to photoperiod and thermoperiod combinations, in and out of phase, show that temperature is more important in inducing standby and emerging behaviour than light alone. For the second step, factors such as temperature, light and the presence of the female sex pheromone determine whether males will leave the standby position and emerge onto the ground. The female sex pheromone stimulates standby beetles to exhibit emerging and wing vibration behaviours, although the effect depends on when it is presented to beetles. Beetles burrow back into the soil; this behaviour is influenced by illumination and time of the day but not by temperature. The results suggest that D. ishigakiensis possesses a sophisticated mechanism controlling male emergence from the soil.

Letter to the Editor on ‘Effects of exposure to a mobile phone on testicular function and structure in adult rabbit’ by Salama et al.

Dear Editor, Recently, a paper was published (Salama et al., 2008) describing the effects of electromagnetic fields from a mobile phone on testicular functions in New Zealand White (NZW) rabbits. We have a number of concerns; the two most important ones deal with the exposure conditions and the biological effects respectively. Exposure was carried out by a GSM mobile phone at 800 MHz in ‘standby position’. In standby mode (we assume that this is meant by ‘standby position’), a GSM mobile phone does not transmit RF electromagnetic fields, as in talk mode, except for short signals once in a while (every 0.5 h up to several hours, depending on the network operator) indicating its presence to the base station. Therefore, the animals were not exposed to high-frequency electromagnetic fields for eight hours per day, but only for a few seconds! The reported whole-body SAR values of 0.43 W/kg are therefore probably wrong because we expect they were calculated for the transmit frequency. Besides, GSM 800 is not the standard for mobile communication in Japan (where the experiments were performed). Although the authors did not give any details of how they measured the electric fields, it appears very likely that they used a broadband probe which picks up fields usually between 100 kHz and some GHz. Actually, a measurement of several GSM mobile phones fields in the laboratory of IMST revealed electrical field strengths of approximately 3 V/m directly at the phones’ display. A frequency analysis showed, however, that the emissions were mainly in the kHz range and they originate from the phones’ internal electronics (e.g. display processor, switching power supply). The other point of concern relates to the reported values for sperm counts (Fig. 2, Salama et al., 2008), and sperm motility (Fig. 3, Salama et al., 2008) respectively, showing (in both control groups and the exposed group until week 7) negligible coefficients of variation (CV; standard deviations divided by the means) of approximately 3%, and only minute changes in the mean values (<4%) during the experimental period of 12 weeks. In other words, both the within- and the between-variability of these parameters are exceptionally small and in sharp contrast to previously published data on NZW rabbits (Williams et al., 1990), showing CVs which are higher by an order of magnitude. Also, the extremely sudden (and thereafter entirely stable) effects on sperm counts and motility respectively are biologically incomprehensible. We therefore express our severe concerns about the validity of the exposure conditions and the reported biological effects in the study.

Retracted: Effects of exposure to a mobile phone on testicular function and structure in adult rabbit

The accumulating effects of exposure to electromagnetic radiation emitted by a conventional mobile phone (standby position) on the testicular function and structure are not yet fully investigated. To study these effects longitudinally, a total of 24 adult male rabbits were randomly and equally divided into three groups. Rabbits in the first (phone) group were exposed, in specially designed cages, to radio frequency emitted from the mobile phone (800 MHz) in a standby position opposite to that of testes for 8 h daily for 12 weeks. The second group consisted of the stress controls which were kept in the same kind of cages to appreciate any cage-induced anxiety. The third group included the ordinary controls which were kept in the conventional roomy cages. Semen analysis and sperm function tests (viability, hypo-osmotic swelling and acridine orange) were conducted weekly. Histological testicular sections and serum total testosterone were also evaluated. A drop in the sperm concentration appeared in the phone group at week 6. This became statistically significant at week 8, compared with the two control (stress and ordinary) groups (133, 339 and 356 x 106/mL, respectively) and to the initial sperm count (341 x 106/mL) of this group. Motile sperm population showed similarity amongst the three study groups until week 10 when it declined significantly, and thereafter in the phone and stress control groups, with more significant decline in the phone animals (50, 61 and 72.4%, respectively). Histological examination showed also a significant decrease in the diameter of seminiferous tubules in the phone group vs. the stress and ordinary controls (191 microm vs. 206 and 226 microm, respectively). The other study points did not show any difference. In conclusion, low intensity pulsed radio frequency emitted by a conventional mobile phone kept in the standby position could affect the testicular function and structure in the adult rabbit.

Effects of exposure to a mobile phone on sexual behavior in adult male rabbit: an observational study

The accumulating effects of exposure to electromagnetic radiation emitted by a conventional mobile phone (MP) on male sexual behaviour have not yet been analyzed. Therefore, we studied these effects in 18 male rabbits that were randomly divided into phone and control groups. Six female teasers were taken successively to the male's cage and the copulatory behavior was recorded. Serum total testosterone, dopamine and cortisol were evaluated. The animals of the phone group were exposed to MPs (800 MHz) in a standby position for 8 h daily for 12 weeks. At the end of the study, the copulatory behavior and hormonal assays were re-evaluated. Mounts without ejaculation were the main mounts in the phone group and its duration and frequency increased significantly compared with the controls, whereas the reverse was observed in its mounts with ejaculation. Ejaculation frequency dropped significantly, biting/grasping against teasers increased notably and mounting latency in accumulated means from the first to the fourth teasers were noted in the phone group. The hormonal assays did not show any significant differences between the study groups. Therefore, the pulsed radiofrequency emitted by a conventional MP, which was kept on a standby position, could affect the sexual behavior in the rabbit.

The effects of microwave emitted by cellular phones on ovarian follicles in rats

The aim of this study was to investigate whether there were any toxic effects of microwaves of cellular phones on ovaries in rats. In this study, 82 female pups of rats, aged 21 days (43 in the study group and 39 in the control group) were used. Pregnant rats in the study group were exposed to mobile phones that were placed beneath the polypropylene cages during the whole period of pregnancy. The cage was free from all kinds of materials, which could affect electromagnetic fields. A mobile phone in a standby position for 11 h and 45 min was turned on to speech position for 15 min every 12 h and the battery was charged continuously. On the 21st day after the delivery, the female rat pups were killed and the right ovaries were removed. The volumes of the ovaries were measured and the number of follicles in every tenth section was counted. The analysis revealed that in the study group, the number of follicles was lower than that in the control group. The decreased number of follicles in pups exposed to mobile phone microwaves suggest that intrauterine exposure has toxic effects on ovaries. We suggest that the microwaves of mobile phones might decrease the number of follicles in rats by several known and, no doubt, countless unknown mechanisms.

Effects of coldness on the protective performance of earmuffs

The type test of hearing protectors (HPD) for certification purposes will be conducted in laboratory at room temperature. Optionally, the mechanical durability of HPDs will be tested in cold environment by a drop test. The purpose of this study was to find out the relevance of the drop test, the change of performance in HPD protection, and finally to estimate the possible change of protection efficiency against noise in cold environment. In total, 22 HPDs were selected to the measurements: 18 earmuffs, and 4 earmuffs attached to an industrial helmet. Attenuation of each earmuff cup was measured by applying insertion loss method for the test subjects in cold. The change of attenuation and temperature of cushion ring was followed up to nine minutes using 30-second intervals for sampling. Three HPDs were damaged in the test. The replaceable cushion was broken in two earmuffs and in one helmet-mounted HPD. The replaceable parts were replaced, and the HPD with attachment failure was removed from insertion loss measurement. In nine HPDs the relative change was less than 3 dB, and was at worst 10 dB. This change was typically at low frequencies, 125 Hz at the beginning when cooled HPDs were placed. In various HPDs the time to get the attenuation levelled varied from 1.5 minutes to 8 minutes. The recovery was dependent on the temperature of the cushion ring. In all cases the temperature of the full attenuation was achieved when the cushion ring reached 7 degrees C. This temporary decrease in attenuation will have a minor effect to the protection efficiency, when the HPD is used full time during the whole exposure duration. A typical group of forest workers will have their exposure interrupted. The chain saws have to refuel, and the chain needs to be sharpened about every 40 minutes. During 6 hour daily operational time there will be about 9-10 minute break, long enough to cool the cushion ring back to below zero at -10 degrees C, if the helmet mounted earmuffs are placed in stand-by position. In the worst case this will cause 1.6 dB increase in daily exposure level to noise.

IS THERE A RELATIONSHIP BETWEEN CELL PHONE USE AND SEMEN QUALITY?

This study was conducted to determine a possible relationship between regular cell phone use and different human semen attributes. The history-taking of men in our university clinic was supplemented with questions concerning cell phone use habits, including possession, daily standby position and daily transmission times. Semen analyses were performed by conventional methods. Statistics were calculated with SPSS statistical software. A total of 371 were included in the study. The duration of possession and the daily transmission time correlated negatively with the proportion of rapid progressive motile sperm (r = -0.12 and r = -0.19, respectively), and positively with the proportion of slow progressive motile sperm (r = 0.12 and r = 0.28, respectively). The low and high transmitter groups also differed in the proportion of rapid progressive motile sperm (48.7% vs. 40.6%). The prolonged use of cell phones may have negative effects on the sperm motility characteristics.

Fast reciprocating probe assembly for the Hanbit magnetic mirror device

A fast reciprocating probe assembly (RPA), which can scan a long length up to 100 cm (with maximum velocity of 136 cm/s), is fabricated to measure basic plasma parameters during a plasma discharge time (∼500 ms) in the Hanbit magnetic mirror device. The probe driving mechanism consists of two steps of movements; first a slow movement to set the probe at a standby position, and then a fast one to measure plasma parameters within an adjustable time interval. Both movements are driven by only a pneumatic system. This is a distinctive feature of the probe drive system that has advantages of a simple driving mechanism and an easy adjustment of the fast stroke length for the wide range. The probe head is fabricated as a modular type for easy replacement. Performance test results and initial measurements from the fabricated RPA will be discussed.

THE MORCELLATOR KNIFE

In Brief Background Cutting the cervix, morcellation, and extraction of the uterus and myomata remain major problems in endoscopic surgery. We developed an efficient, safe, reusable, and inexpensive instrument to cut the cervix and morcellate the uterus and myomata: the morcellator knife. Instrument The morcellator knife is a classic lancet with an interchangeable blade, transformed into an endoscopic instrument that can be inserted easily through a 10-mm-diameter trocar. The blade has an automatic retraction system and is set in the standby position, ensuring security. Cutting the cervix and uterine or myoma fragmentation are easy. The mass to be cut is held between two grasping forceps for easy cutting with the blade, under permanent visual control. After morcellation, extraction of the masses is performed through a posterior culdotomy. Experience We have used this morcellator knife in 54 subtotal hysterectomies and 16 myomectomies. There were no complications during the procedures. Morcellation lasted 3–14 minutes and involved the use of an average of two to three blades. Conclusion The morcellator knife is a simple, safe, reusable, and inexpensive instrument with a low maintenance cost. A new, safe, simple, and inexpensive instrument can be used to cut the cervix during endoscopic supracervical hysterectomy and morcellation of the uterus or leiomyomata.

Whole-body microwave exposure emitted by cellular phones and testicular function of rats.

This study investigated whether there are adverse effects due to microwave exposure emitted by cellular phones in male rats. Eighteen Wistar Albino rats were separated into three groups, a sham group and two experimental groups. The rats were confined in Plexiglas cages and cellular phones were placed 0.5 cm under the cages. In the first experimental group, cellular phones were in standby position for 2 h. In the second experimental group, phones were turned to the speech position three times each for 1 min duration over 2 h. Rats in the first and second experimental groups were exposed to microwaves emitted by phones for 2 h/day for a duration of 1 month. After the last exposure the rats were killed. Brain, eyes, ears, liver, heart, lungs, stomach, kidneys, testes, small and large intestines and skin of the rats were observed histologically. The decrease of epididymal sperm counts in the speech groups were not found to be significant (P > 0.05). Differences in terms of normal and abnormal sperm forms were not observed (P > 0.05). Histological changes were especially observed in the testes of rats of the speech groups. Seminiferous tubular diameter of rat testes in the standby and speech groups was found to be lower than the sham group (P < 0.05). Rectal temperatures of rats in the speech group were found to be higher than the sham and standby groups (P < 0.05). The rectal temperatures of rats before and after exposure were also found to be significantly higher in the speech group (P < 0.05). Specific absorption rate (SAR) was determined as 0.141 W/kg.

Military Medicine Responds to Terrorism

MENTAL HEALTH teams from Landstuhl (Germany) Regional Army-Air Force Medical Center are working with survivors of the terrorist bombing of the Khobar Towers US military housing complex in Dhahran, Saudi Arabia. At the same time, the approximately 20 000 US military people serving in the Persian Gulf area are bracing for possible further terrorism. Military medical personnel are reviewing emergency support plans. Some of this emergency medical planning was put into effect promptly after the housing in Dhahran's al-Khobar suburb was blasted by a truck bomb. Forward Area Surgical Teams from Ramstein (Germany) and Incirlik (Turkey) bases rushed to the scene. And a Critical Care Augmentation Transport Team that was supporting North Atlantic Treaty Organization peace enforcers in Bosnia-Herzegovina moved into standby position. Some 30 US Air Force medical personnel already were stationed at the Dhahran area King Abdul Aziz Air Base staging site, including 4 physicians. One flight surgeon

Nonparametric methods for 1-out-of-2: G repairable systems

The steady state availability of 1-out-of-2 : G repairable system is obtained under the assumption that the life time of a component in standby position follows exponential distribution. It's nonparmetric estimator is proposed. The asymptotic properties of the estimator are used to provide the fixed width coinfience interval with specified coverage probability and testing of hypothesis problem using sequential procedure.

Ergodicity conditions for queueing systems with repeated calls

Systems with repeated calls are closely related - as far as the analysis of the limiting behavior as the time {tau}{yields}{infinity} is concerned - to systems with restrictions [1, 2]. These systems are of interest to mathematicians mainly because their obvious importance in various applications (communication theory, air traffic control, information systems) when a customer who was refused service (an aircraft which cannot land in an airport because the landing strip is occupied) is directed into a standby position from which the demand for service is then repeated at random periods of time (an aircraft circles and then attempts another landing). A special feature of these systems is that even when there are customers at standby, the server may be idle, thus reducing the capacity of the system. Moreover, there can be restrictions on the duration of a customer at a standby position or on the number of repetitions allowed. Service disciplines may also vary. All this resulted in a wide variety of models with repeated calls especially in the engineering literature. Moreover, conditions for the existence of a stationary state are either not considered at all or are determined for special models under the simplest assumptions on the controllingmore » sequence which allows us to utilize the known ergodicity criteria for Markov chains.« less

Ribosome-mRNA contact sites at different stages of translation initiation as revealed by cross-linking of model mRNAs

Two model mRNAs, one with and one without the Shine-Dalgarno (SD) sequence, were bound to Escherichia coli 30S ribosomal subunits in the presence and absence of initiation factors and initiator tRNA and then cross-linked by diepoxybutane. The distribution of the cross-linked mRNA among rRNA and tibosomal proteins (r-proteins) and the extent to which individual r-proteins react was found to be affected by the presence or absence of the SD sequence and by the initiation factors and initiator tRNA. The results are consistent with the hypothesis that the position of the 30S-bound mRNA is shifted under the influence of the initiation factors and fMet-tRNA from a stand-by position towards a second site where the decoding of the initiation triplet by the initiator tRNA occurs

Development of a vision-based inspection system on a micro-computer

The role of inspection in achieving enhanced quality and productivity is of paramount importance. There is a trend towards more reliable methods of inspection—like, machine vision, automated inspection, computer-aided inspection, etc. But, for these newer inspection systems to be attractive, these need to be cost-effective. The present paper is based on a project which was concerned with the design and development of an automated micro-based system integrating machine vision with a robot to carry out inspection tasks. To simulate a real-world industrial process, the inspection of common washers has been carried out using the system. Depending on the outcome of the inspection process, the robot arm gets activated to pick a washer and transfer it in a good/bad bin, or place it on an assembly workstation. The manipulator next returns to its standby position and remains there until a new target is presented. The special features of the inspection are: (i) micro-computer based, (ii) low-cost, being under $7500, (iii) flexible and reprogrammable, and (iv) likely to remain effective at the shop floor.

Simulation of an Aircraft Accident at Brussels Airport

The exercise held at Brussels Airport was carried out by inexperienced personnel to highlight the most common errors and shortcomings of an existing disaster plan.INCIDENT COMMUNICATIONOnce an aircraft is known to be in trouble, all the nearby fire brigades are alerted by means of the unique call number 900 and move to take up their stand-by position close to the landing point. The Military Hospital is also alerted and sends out a liaison car, with a doctor among its occupants. This car joins the stand-by position. Once the aircraft has crashed, the fire engines rush to the site and all the major university hospitals and the Military Hospital are notified by the same 900-code number. Disaster teams arrive by road.This report is almost exclusively limited to aspects of rescue, triage, on-site stabilization, and evacuation of the casualties.

Stand-by position of the dioxygen-dependent ubiquinone-8 synthesis apparatus in anaerobically grown Escherichia coli K-12

Stand-by position of the dioxygen-dependent ubiquinone-8 synthesis apparatus in anaerobically grown Escherichia coli K-12

Stand-by position of the dioxygen-dependent ubiquinone-8 synthesis apparatus in anaerobically grown Escherichia coli K-12

Stand-by position of the dioxygen-dependent ubiquinone-8 synthesis apparatus in anaerobically grown Escherichia coli K-12