Rubber Ring Research Articles

Effects of age on the electroencephalographic response to castration in lambs anaesthetized with halothane in oxygen from birth to 6 weeks old

ObjectivesTo characterize changes in the cerebro‐cortical response of lambs to rubber‐ring castration during the first 6 weeks of postnatal life. AnimalsCoopworth‐Texel cross ram lambs between 3 hours and 44 days of age. MethodsThe electroencephalogram (EEG) and heart rate responses to rubber ring castration were compared. Anaesthesia was induced via a face mask and maintained with halothane in oxygen (e′Hal = 1.2%). Once a stable plane of anaesthesia had been achieved, data collection of EEG and electrocardiogram (ECG) commenced, and the lambs were castrated 15 minutes later, using rubber rings. Heart rate was derived from the ECG and the median frequency (F50), spectral edge frequency (F95) and total power (ptot) were derived from the EEG. ResultsCastration‐induced changes in F50 increased from 2 ± 1.8% in the youngest lambs to a maximum of 33 ± 8.9% in the 36 ± 0.5 day‐old lambs. Changes in F95 increased from −7 ± 3% in the youngest lambs to a maximum of 16 ± 11% in the 36 ± 0.5 day‐old lambs. Linear regression analysis in lambs up to 10 days of age demonstrated a change in the response with age that was significantly different from zero for F50 (r2 = 0.28, p = 0.007) and F95 (r2 = 0.38, p = 0.001), but not for ptot or heart rate. ConclusionThis study identified significant changes in the responsiveness of the lambs’ cerebral cortex to the noxious stimulation of castration over the first 7–10 days of postnatal life. The results suggest that mechanisms that suppress responses of the fetus to noxious stimulation may still be active in the first few days after birth. Clinical relevanceThis study documents changes in central nociceptive processing which may reflect the ability of neonatal animals to perceive pain.

The Effects of Docking on Growth Traits, Carcass Characteristics and Blood Biochemical Parameters of Sanjabi Fat-tailed Lambs

The effects of docking on growth traits, fattening performance, carcass characteristics and blood biochemical parameters were investigated using 24 fat-tailed Sanjabi single-born male lambs raised from a large commercial sheep herd. The lambs were randomly divided into two groups. One group (n = 12) were docked at two days of age with rubber-rings using an elastrator. The second group (n = 12) were left intact. After weaning (90 days), all lambs were moved to rustic rangelands for 40 days. Then all the lambs were fed concentrates ad libitum for 60 days during the fattening period. Growth traits, body weight and average daily gain (kg) were recorded at the end of the weaning and fattening periods. Blood biochemical parameters including urea, total protein, glucose, triglycerides, cholesterol, low-density lipoproteins (LDL) and high-density lipoproteins (HDL) were measured during the fattening period. Finally, at the end of the fattening period, eight lambs (4 intact and 4 docked lambs) were slaughtered in order to determine carcass characteristics. Fat-tail docking had no effect (p>0.05) on lamb growth from birth to weaning. Body weight and average daily gain of docked lambs were significantly higher (p<0.05) than for intact lambs at the end of the fattening period. There was no difference in carcass measurements between the two groups, except for chest depth and leg weight which were higher (p<0.05) in docked lambs. During the fattening period, cholesterol and LDL of docked lambs were less than in intact lambs (p<0.05). The current results indicated that docking with rubber rings causes an improvement in growth traits during the fattening period and leads to desirable carcass characteristics compared to intact lambs; interestingly, this procedure had a significant effect on the lowering of blood cholesterol and LDL of docked lambs.

Wear and energy-saving freight bogie designs with rubber primary springs: principles and experiences

The traditional radial steering bogie with swing hanger links is known to be track-friendly but heavy, and expensive in investment and maintenance costs. Whereas the actual bogies with longitudinal stiff axle guidance such as Y25 cause severe wear on wheels and rails in curves, and also develop high running resistance in curves. Bogies with rubbers springs like double rubber ring spring (DRRS), Leicht und LaermArm (LEILA) low weight and low noise, and Gigabox are a new feature with good behaviour in curves and on straight tracks. Good experience over many years with DRRS and 35 t axle load on the German Rheinisch Westfaelische Elektrizitaetswerke (RWE) coal line prove its benefits. For the new designs, LEILA and Gigabox, which are being introduced into the market now, even higher benefits can be demonstrated. The principle design features and the benefits regarding lateral track forces, wear, and traction resistance are evident. Also noise behaviour is an increasing demand for freight operation.

Effect of Docking and Diet Energy on Carcass Fat Characteristics in Fat-Tailed Baluchian Sheep

Effects of docking on carcass fat characteristics were studied in fat-tailed sheep. Male lambs were randomly divided into 2 groups. One group was docked after birth using rubber rings, and the tails of the other group were left intact (control). After weaning, 20 lambs from each group were divided into 2 subgroups; one subgroup was fed with a normal energy diet (10.25 MJ/kg ME) and the other one with a high-energy diet (11.42 MJ/kg ME) for 84 days. At the end of the fattening period, 28 lambs were slaughtered for determination of warm carcass weight (WCW) and other carcass characteristics. At 24 h postmortem samples of meat, omental fat, and caudal fat were taken from chilled (4 °C) carcasses for the assessment of fatty acid (FA) composition. No significant difference (P > 0.05) was observed in WCW and omental fat between carcasses of docking and control lambs, but lambs on 2 types of energy diets showed a significant difference (P < 0.05). Under these circumstances, docked lambs produced leaner carcasses than intact lambs (P < 0.05). Diet energy had a significant effect on average daily gain and daily feed intake (P < 0.05). Results showed that the predominant FA in body fat was oleic acid and a significant difference was observed for percentage of FA composition between fat in different parts of body (P < 0.05).

Can Romney ram lambs whose scrotums had been shortened by the use of a rubber ring be used as an alternative to vasectomised Perendale rams for inducing early breeding activity in Romney ewe lambs?

AIM: To determine if exposure to ram lambs whose scrotums had been shortened by the use of a rubber ring would induce reproductive activity in ewe lambs, and determine if this technique was an effective alternative to vasectomised mature rams. METHODS: Seven hundred and forty-nine Romney ewe lambs, 7–8 months of age, were randomly assigned to one of three treatment groups. Treatments included exposure for 17 days prior to breeding to either mature vasectomised rams (Vasec), or ram lambs whose scrotums has been shortened via a rubber ring (Ram SS), or not being exposed to either vasectomised or short-scrotum ram lambs (Unteased). Using crayon marks, ewe lambs were identified as having been marked during the first 17 days only, during both 17-day periods, during the second 17 days only, or not marked. Hoggets were weighed on the day of introduction of entire rams. All ewe lambs were diagnosed for pregnancy status using ultrasound. RESULTS: Unteased ewe lambs and those exposed to ram lambs whose scrotums had been shortened by the use of a rubber ring were less (p<0.05) likely to be marked and pregnant to the first 17 days of breeding than ewe lambs exposed to mature vasectomised rams. Twin-bearing ewe lambs were heavier (p<0.05) than their single-bearing counterparts at introduction of the rams. CONCLUSION: Exposure of ewe lambs to mature vasectomised rams is an effective means of increasing the numbers of ewe lambs bred and pregnant to the first 17 days of breeding. In contrast, a 17-day exposure to ram lambs whose scrotums had been shortened by the use of a rubber ring, at the ratios utilised in the present study, were not a suitable alternative to mature vasectomised rams for inducing early breeding activity in ewe lambs.

Sexual foreplay incontinence in men with erectile dysfunction after radical prostatectomy: a clinical observation

Incontinence is a known complication of radical prostatectomy for prostate cancer. Recently, climacturia, or orgasmic incontinence, has been reported after this procedure. Patients have occasionally reported some loss of urine during sexual foreplay, even when general daytime incontinence was not present. A review of questions on this subject was conducted in 45 men to better appreciate how often this occurred. Nine of twenty-four men (38%) with no daytime incontinence stated that they had some incontinence with sexual foreplay. These men involved have related that this causes embarrassment and frustration, with the effect of avoidance of sexual activity. This in turn causes relationship problems. The use of a rubber ring at the base of the penis during foreplay can help relieve this difficulty.

2P1-D24 マイクロ多分岐切換バルブチップの開発 : 駆動機構の改良とバルブ性能測定(ナノ・マイクロ流体システム)

This paper describes the Improvement of the multi-directional micro switching valve chip with ten outlets. Designed for air-pressure driven micro dispenser systems, this switching valve chip has a special rotary mechanism with a silicone rubber ring to prevent leaks and a precise auto-positioning mechanism. The design of the switching valve was optimized to enable a micro solenoid (IN, 6V DC) to be built into the chip, allowing this chip to quickly switch among ten outlets under high pressure (higher than 500kPa). As the next step, the switching valve has been improved to the drive mechanism that doesn't need fine adjustment. Moreover, the valve performance except proof pressure were evaluated experimentally.

Band Ligation of the Perforated Gall Bladder During Laparoscopic Cholecystectomy

Perforation of the gall bladder is a frequent complication during laparoscopic cholecystectomy. Grasping the perforated part of the gall bladder, clip application, or endoscopic loop application are possible solutions to prevent spillage. We propose laparoscopic rubber band application to close the perforated part of the gall bladder as an easy and safe method. We performed rubber band application after iatrogenic perforation of the gall bladder during laparoscopic cholecystectomy in 5 patients. Two-millimeter-wide multiple rubber rings, cut from a 14-Fr Foley catheter, are loaded on a grasper. When a perforation occurred during the dissection of the gall bladder, the hole is grasped with this instrument and 1 of the rings is placed on the gall bladder by the aid of a dissector. Thus, the grasper remained available for traction of the Hartmann's pouch during further dissection of the gall bladder. The rubber bands were placed successfully in all cases. Two perforations occurred in 1 case, and 2 bands were placed with ease. Bile leakage or gall stone spillage did not occur. Operation time was not prolonged. Rubber band ligation of perforation of the gall bladder is a simple, safe, inexpensive, and effective method to prevent spillage of the bile or gallstones in laparoscopic surgery.

Elastomeric impression as a diagnostic method of cavitation in proximal dentin caries in primary molars

The purpose of this study was to validate the elastomeric impression after temporary tooth separation as a method of cavitation detection in proximal caries lesions in primary molars with outer half dentin radiolucency. Fifty-one children (4-10 years old), presenting radiolucency in the outer half of the dentin at the proximal surfaces of primary molars and proximal anatomic contact with the adjacent tooth (without restoration/cavitated caries lesion) were enrolled in the study. Temporary tooth separation was performed with an orthodontic rubber ring placed around the contact point during 2-3 days. Thereafter, impression of the proximal surfaces was made. The elastomeric impressions were classified as "non-cavitated" or "cavitated" surfaces. Visual inspection after tooth separation was considered as the gold standard. Examiner reliability of visual inspection after tooth separation was determined (kappa 0.92). Impression examination was repeated every 5 participants to evaluate the reproducibility of the method. The frequency of cavitated lesions was 65%, and 67% of those were inactive. Sensitivity, specificity, positive and negative predictive values were 0.88% (95%CI 0.73-0.95), 0.89% (95%CI 0.67-0.97), 0.94% (95%CI 0.79-0.98) and 0.80% (95%CI 0.58-0.92), respectively. Impression examination showed total agreement regarding cavitation. The evaluation of elastomeric impression after tooth separation is a useful clinical resource in cavitation detection for clinicians and researchers when visual inspection is doubtful.

Multi-directional micro-switching valve chip with rotary mechanism

This paper describes the development of the world's first multi-directional micro-switching valve chip with 10 outlets. Designed for air-pressure driven micro-dispenser systems, this switching valve chip has a special rotary mechanism with a silicone rubber ring to prevent leaks and a precise auto-positioning mechanism. The design of the switching valve was optimized to enable a micro-solenoid (1 N, 6 V DC) to be built into the chip, allowing this chip to quickly switch among 10 outlets under high pressure (higher than 500 kPa). The switching valve chip was fabricated using our original method of hybrid microstereolithography (hybrid-IH process), thereby eliminating the need for microassembly and bonding.

In vivo experiments with tracheostoma tissue connector prototypes

In cancer patients who have undergone total surgical removal of the larynx, ideally voice rehabilitation should be performed using a shunt valve (placed in a fistula of the tracheo-esophageal wall) and a tracheostoma valve (TSV) to enable hands-free tracheo-esophageal speech. A tracheostoma is created by suturing the trachea into the lower anterior part of the neck, and a TSV is a device that can be placed at the stoma. Unfortunately, many patients are unable to use a TSV, mainly due to fixation difficulties. To improve the fixation of the TSV, tracheostoma tissue connector (TS-TC) prototypes have been designed. Prototype 1 consisted of a titanium ring, inner diameter 30 mm, with a circular polypropylene mesh glued to it with silicone adhesive. Four holes had been drilled into the ring for the insertion of sub- and percutaneous screws. Prototype 2 consisted of a silicone rubber ring, inner diameter 30 mm, combined with polypropylene mesh and four titanium inserts that functioned as a base plate for the insertion of sub- and percutaneous screws. In adult female goats a tracheostoma was created and the prototypes were implanted. After 6 weeks of subcutaneous implantation, percutaneous screws were inserted. After twelve weeks, the experiment was terminated and the implants with the surrounding tissues were processed and examined histologically. The clinical appearance during weeks 7-12 varied from very poor to relatively good. Histologically, the implants showed a uniform inflammatory response. We found that all the tissue surrounding the screws showed signs of epithelial down growth. It was concluded that the two-stage implantation procedure of our prototype TS-TCs in this animal model was unsuccessful. Additional research efforts are necessary to improve tissue immobilization and to devise reliable fixation systems for TSVs.

Einfluss der Lokalanästhesie auf Kurz- und Langzeitschmerzen verursacht durch drei unblutige Kastrationsmethoden beim Kalb

Behavioural and cortisol responses of calves were used as indicators of pain to assess short- and long-term effects of three bloodless castration methods with and without local anaesthesia. Eighty calves, aged 21 to 28 days, were control handled (20) or castrated by Burdizzo (25), rubber ring (25), or crushing technique (10). Either a total volume of 10 ml of Lidocaine or NaCl was distributed in both spermatic cords and the scrotal neck. The plasma cortisol response was monitored for 72 hours, and behavioural and clinical traits over a three-month period. Castration success was assessed by degree of atrophy and histological tissue examination. The crushing technique cannot be recommended due to incomplete castration success, and the evaluation was stopped after 10 animals. Local anaesthesia reduced the level of indicators of acute pain after Burdizzo and rubber ring technique. It did, however, not result in a totally painless castration. When castration is performed at the age of 3 to 4 weeks, the rubber ring but not the Burdizzo method showed evidence of chronic pain lasting for several weeks.

Einfluss der Lokalanästhesie auf Schmerz und Stress verursacht durch unblutige Kastrationsmethoden beim jungen Lamm

Behavioural and cortisol responses of lambs were used as indicators of pain and distress to assess short- and long-term effects of bloodless castration methods with and without local anaesthesia. Eighty lambs, aged 2-7 days, were control handled or castrated by crushing- Burdizzo- or rubber ring method with and without local anaesthesia. Either 4 mg/kg diluted lidocaine, or corresponding volumes of physiologic sodium chloride solution were distributed in both spermatic cords and the scrotal neck. The serum cortisol response was monitored for 48 h, behavioural- and clinical traits over a 3-month period. The crushing castration method was excluded from the study after 10 lambs had been castrated, since this method showed severe local reactions. Local anaesthesia significantly reduced behavioural and cortisol responses after rubber ring castration and tendentially after Burdizzo castration. Prolonged or chronic pain after rubber ring castration with anaesthesia was not evident. If combined with local anaesthesia, both the rubber ring and the Burdizzo method are acceptable methods for castration of lambs up to one week of age.

The influence of strength-endurance training on the oxygenation of isometrically contracted forearm muscles

Ice-climbers frequently use the squeezing of rubber rings for increasing their isometric strength-endurance in the forearm muscles. The aim of this study was to ascertain whether such training influences oxygenation and endurance of forearm muscles at higher as well as lower testing intensities. Fourteen healthy young ice-climbers were divided and randomized into two groups. Group A performed a specific ice-climbing test, an ice-axe-grasping (axe weight 750 g) until fatigue. Group B performed 150 N isometric hand-squeezing of dynamometer until fatigue. Both groups performed similar training of squeezing a rubber ring at 30% of Maximal Voluntary Contraction (MVC) for 6 weeks. The forearm oxygenation was assessed by relative saturation of oxygen (RSO(2)), total hemoglobin concentration (RTOTHb), the concentration of oxygenated hemoglobin (ROXYHb) and concentration of deoxygenated hemoglobin (RDEOXYHb). The results revealed that muscle strength-endurance training increased performance of forearm muscles during 150 N contraction with an accompanied increase in oxygenation of the exercising muscles. In contrast, the same training did not influence the performance of forearm muscles during ice-axe-grasping in spite of increased oxygenation. Muscle oxygenation during intense isometric contraction is low in spite of an increase observed in training. This may be due to oxygenation levels that were below the limit where oxygenation may influence the duration of the contraction. Increased oxygenation may have occurred due to an increased blood flow and perfusion through superficial muscles or layers may not have contributed to the generation of the force of the contraction, as would be the case in deeper muscle layers.

Improving the durability of the initial sections of continuous casters Nos. 2 and 3 at the Magnitogorsk Metallurgical Combine

To eliminate the main reason for the jamming of continuous-caster rollers-the entry of water, scale, etc., into the region of the bearing assembly-designers have developed a new assembly with rubber and fluoroplastic seals. The seals are composed of rubber (grade TKMShch) and fluoroplastic (fluoroplast-4) rings. To reduce the friction coefficient, the shaft is clad with brass before the fluoroplastic is applied. The bearing cap is cast iron. Mobile-Gris is used as a protective lubricant. A bushing which is kept from rotating by a pin is installed between the shaft and the cap to protect the shaft from wear. The bushing is also clad with brass and then covered with the fluoroplastic to reduce friction.

Numerical simulation of sheet metal drawing by Maslennikov's technique

Abstract The applicability of numerical simulation to the sheet metal drawing by Maslennikov's technique is examined. A circular cup drawing process is numerically simulated using the dynamic explicit finite element code DYNA3D. The effect of the forming parameters, such as dimension and hardness of the rubber ring, frictional coefficient of the interface between the sheet and the rubber ring and mechanical properties of the sheet, on the sheet deformation is investigated. The increment in the cup depth obtained by each drawing operation tends to decrease with the number of times of the operations. The effect of frictional coefficient of the interface between the sheet and the rubber ring on the sheet deformation is not prominent. The sheet drawing with a harder rubber produces the deeper cup. On the other hand, the sallower cup is obtained with a thicker rubber ring. These demonstrated deformation behaviors are considered qualitatively adequate, therefore, it is concluded that the numerical simulation may be helpful in determining the forming conditions for the sheet metal drawing by Maslennikov's technique.

Dynamic Characteristics of Exhaust Hanger Composed of Rubber and Thin Metal Ring

The dynamic characteristics of exhaust hangers for automotive use are studied for high frequencies at which the resonance vibration of the exhaust hangers occurs. A newly developed exhaust hanger composed of rubber and a thin metal ring is presented, which can provide a lower dynamic stiffness in a wide frequency range than an exhaust hanger made of solid rubber. A dynamic characterization testing and finite-element analysis of the exhaust hangers were carried out to clarify the frequency responses of dynamic stiffness in the high-frequency range. A method of treating the viscoelasticity of the rubber material using the finite-element method is proposed to predict the dynamic characteristics of the exhaust hangers. The finite-element method results show a good agreement with the experimental results for the frequency response of dynamic stiffness. Concerning the newly developed exhaust hanger, the effects of metal ring geometry and rubber hardness on the dynamic stiffness are examined to demonstrate the design principle for providing a low dynamic stiffness in a wide frequency range.

Inhibitory Effects of Prior Low-dose X-irradiation on Ischemia-reperfusion Injury in Mouse Paw

We have reported that low-dose, unlike high-dose, irradiation enhanced antioxidation function and reduced oxidative damage. On the other hand, ischemia-reperfusion injury is induced by reactive oxygen species. In this study, we examined the inhibitory effects of prior low-dose X-irradiation on ischemia-reperfusion injury in mouse paw. BALB/c mice were irradiated by sham or 0.5 Gy of X-ray. At 4 hrs after irradiation, the left hind leg was bound 10 times with a rubber ring for 0.5, 1, or 2 hrs and the paw thickness was measured. Results show that the paw swelling thickness by ischemia for 0.5 hr was lower than that for 2 hrs. At 1 hr after reperfusion from ischemia for 1 hr, superoxide dismutase activity in serum was increased in those mice which received 0.5 Gy irradiation and in the case of the ischemia for 0.5 or 1 hr, the paw swelling thicknesses were inhibited by 0.5 Gy irradiation. In addition, interstitial edema in those mice which received 0.5 Gy irradiation was less than that in the mice which underwent by sham irradiation. These findings suggest that the ischemia-reperfusion injury is inhibited by the enhancement of antioxidation function by 0.5 Gy irradiation.

829 弾性ホイールの動的挙動の解析

Flexible wheels have been developed to improve the ride comfort. This wheel is equipped with unique fiber reinforced rubber rings between the disc and the rim, in order to reduce noise and vibration without any compromises with handling and stability. This paper discusses effectiveness of the flexible wheel when weight unbalance added through the uniformity tests, and proposes a new uniformity test method which can simulate more realistic conditions of driving than the conventional method. Simulation analysis was carried out for the new test method, showing that flexible wheels could reduce more radial force variation compared with the conventional wheels.

Multi-directional Switching Valve Chip with the Rotary Mechanism (2nd Report, Proposal of Automatic Switching Mechanism Using the Solenoid)

We have developed the 10-way micro switching valve chip for micro dispenser system. This chip succeeded to switch ten outlets from one inlet without dead volume under high leakage pressure (> 700kPa). The valve was operated manually to confirm the switching principle with the rotary mechanism. As the next step, the micro solenoid drive switching valve chip was developed for simple and quick operation. Positioning and detection of present location at the outlet were achieved with the latch mechanism without necessity of positioning. To build the solenoid into the chip, the valve design parameters (the height of the silicon rubber ring and the compression force to the rotor) affecting the valve performance (the leakage pressure and the rotation force of the rotor) were optimized.