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The fluid borne-vibration generated from a hydraulic pump is known to be one of drawbacks in hydraulic systems. In order to decrease the noise and vibration effectively, the simulation tool to predict the pressure ripple at an arbitrary point in the hydraulic circuit must be used at a design stage. Therefore, accurate mathematical models for hydraulic components is required for such simulation. In this research, the target is set to develop a precise mathematical model for the source impedance characteristics of an axial piston pump. In the past research, the simple approximation models have been already developed to be able to express the source impedance characteristics. These models need the parameter identification for the dimension of discharge passageway by the experimental acquired source impedance. Hence, the models can not be used as a design purpose. In this report, the theoretical investigations which consider shapes and dimensions of a discharge passageway inside the pump, as well as the pump chambers with discharge process, are conducted and compared with the experimental results. It was found that the source impedance of axial piston pump can be modeled by the distributed parameter pipe model which takes into account all pump chambers connecting the discharge port.

Generally, industrial vehicles such as agricultural machines and construction machinery use hydraulic systems for heavy-load work. Also the work often continues for a long time in a certain area. Consequently, noise exposure of the surrounding environment is increased. Thus noise regulations are established in several countries. The noise emitted from the hydraulic system has a significant contribution to the over-all of the noise in an industrial vehicle. Recently, the choice of power sources in industrial vehicles has tended to shift from internal combustion engines to electric motors. Consequently, the contribution of noise emitted from the internal combustion engine will decrease and the contribution of noise emitted from a hydraulic system will become relatively prominent in the future. It is, therefore, more than ever important to take care of the noise generated by the hydraulic system of the industrial vehicles. It is known that speed of sound in hydraulic oil has an effect on pressure ripples which can be source of noise. Therefore, it is important to understand behavior of the speed of sound reasonably in design of quiet hydraulic systems. However, relationship between operating conditions and the speed of sound has not been revealed up to now. In this study, the speed of sound has been investigated at the operating conditions that are oil temperature, loading pressure, volume ratio of entrained air to the hydraulic oil and type of the oil for typical agricultural machines and construction machinery.

It is known that fluid-borne noise emitted from a hydraulic system often causes severe discomfort of the operator. It is also known that the noise can change as the system warms up. The temporal change in steady operation can be a factor for misperception of mechanical failure, because noise can play an important role as a signal that indicates abnormal operation. It is therefore important to understand the behavior of hydraulic pressure ripples that are a source of hydraulic noise in steady operation, and how they change in relation to the operating time. This study has investigated the influence of oil temperature changing over time on pressure ripples in a hydraulic line in steady operation. Variables that can change in steady operation have been considered using mathematical models of the pressure ripples. The consideration has shown that, when there is no air-entrainment from an outer system, the change over time is caused solely by the change of the hydraulic oil temperature. Physical properties of the oil and speed of sound in the oil have been defined as temperature-related variables in the mathematical models. The physical properties that are used in the mathematical models have been obtained directly from the manufacturer. In contrast, the speed of sound in the oil has to be obtained using theoretical approaches. The behaviors of the hydraulic pressure ripples in three simple hydraulic systems have been investigated using mathematical models that took into account the thermal properties. Each hydraulic system consists of a hydraulic pump, a straight pipe and a termination condition that is one of the following typical three types: non-reflection, valve and volume. The mathematical models have shown distinct behaviors resulting from the change in the oil temperature. The behaviors have been verified experimentally.

In fluid power systems, a Helmholtz type hydraulic silencer is often utilized in order to attenuate pressure pulsations, which are detrimental to the system because of the vibration and noise that they generate. The silencer has the important feature that it is effective within a narrow band range around the resonance frequency. Therefore, it is very useful to be able to predict the attenuation characteristics by means of a mathematical model. Previous research has shown that there are noticeable discrepancies between the experimental values and calculated results when the ratio of the volume length L to diameter D is comparatively small. In this paper, a novel distributed parameter model was proposed in order to examine these discrepancies. The mathematical model was derived by taking into account the elastic deformation on the upper and lower vessel walls of a Helmholtz silencer with a flat volume. The analysis revealed that the resonance frequency of the silencer is reduced by a reduction in the volume length or by a reduction in the cover thickness. The reason for this is the reduction of the effective bulk modulus. In addition, experimental work was conducted to examine the attenuation characteristics under various conditions. The experimental results were found to correspond to the mathematical model qualitatively.

Recently, highly efficient small heat transport devices have been required. In particular, pulsating heat pipes (PHP) have come to draw a lot of attention. The contribution of sensible heat transport and latent heat transport in oscillating working fluid, which plays an important role in heat transport performance of PHP, has not been clarified enough experimentally yet. The purpose of this study is to evaluate the contribution of sensible heat transport and latent heat transport experimentally by making liquid column oscillate sinusoidally in the channel. The channel was initially evacuated, and ethanol was charged to form a liquid column, which is called single component system. In addition, the ethanol was charged in the channel with air in the gas phase at atmospheric pressure, which is called two components system. The effective thermal conductivity of latent heat transport is determined by the difference between the effective thermal conductivity in single component system and that in two component system. In two components system, that is sensible heat transport, the effective thermal conductivity decreases monotonically as oscillation center moves to cooling section under the same amplitude, because residence time of liquid column at heating section decreases. On the other hand, in latent heat transport, the effective thermal conductivity increases as oscillation center moves to cooling section under the same amplitude, because liquid film at cooling section becomes longer. In addition, numerical analysis was conducted for sensible heat transport in oscillating working fluid. The comparison of the numerical results with the experimental results indicates that liquid film at the tip of liquid column would enhance sensible heat transport.

Pressure pulsation is caused by the flow ripples from a positive displacement hydraulic pump. It transmits throughout fluid power equipment and causes unwanted excitation of the mechanical parts. In many practical applications, a Helmholtz type hydraulic silencer may be used to attenuate such pulsation. It is the preferred solution on account of its simple structure and high attenuation performance. However the distinctive drawback of this silencer is that it is effective only within a narrow range of the attenuating frequency. Therefore, the silencer is only suitable for use in the hydraulic systems running at constant pump rotational speeds. The purpose of this research is to develop a novel silencer for hydraulic systems that have a fixed displacement pump driven under variable speed. Firstly, a mechanism for adjusting the resonant frequency has been pro-posed. This works by changing the volume of the silencer. Secondly, a prototype of the novel silencer was designed using a new distributed parameter system model, in which the vessel volume was modelled as an annular fluid line. Finally, the at-tenuation characteristics of the prototype silencer were verified by measuring the transmission loss and insertion loss under various conditions, and comparing them with the calculated results.

The noise and vibration caused by pressure pulsation are one of detrimental problems in hydraulic systems. A Helmholtz type hydraulic silencer, which is based on the resonant phenomena of a mass-spring-damper system for its attenuate principle, is known as one of the most practical silencers in the hydraulic systems. In the previous researches, the transmission loss characteristics of the Helmholtz type hydraulic silencer were modeled by a distributed parameter model. However, in the design case that the ratio of the length and diameter L/D of the cylindrical volume is smaller, the resonance frequency of the existing model begins to deviate from the experimental results and the disparity increases with decreasing the ratio of L/D. The purpose of this research is to clarify the influence of a neck and volume geometry on the attenuation characteristics. In particular, a mathematical model that considers the flow for the radial direction of the cylindrical volume is newly proposed for the design case that L/D is smaller. The transmission loss characteristics of the Helmholtz type hydraulic silencer are investigated theoretically for both the proposed model and existing models. In addition, the experimental examination of the influence of volume geometry on the attenuation characteristics is carried out in order to verify the theoretical investigations.

This paper presents a real-time simulation for coupled system with rigid body system and hydraulic system. The equations of motion for the rigid body are derived by transforming the rigid body motion to the linear element motion. The system equations can be presented as the ordinary differential equations of motion for the coupled system of the rigid body system and the hydraulic system without introducing the constraint conditions, describing the motions of the rigid body system using the linear element motion. Then, this modeling is useful for the real time simulation for the coupled system, as numerical stability is improved by carrying out coupled system simulation in one software package. Firstly, rigid body system driven by the linear element is formulated, coupled analysis theory with the hydraulic system is derived, and electric motor drive system is formulated. Finally, the actual digging simulations of a hydraulic excavator are implemented using the present technique. It is clarified that the real time simulation is successfully conducted.

Pseudomyxoma peritonei(PMP)is a rare condition caused by intraductal papillary mucinous neoplasm(IPMN). At our institution, 3 cases, along with literature review, of PMP caused by IPMN were treated with cytoreductive surgery. In case 1, a 70-year-old man was pathologically diagnosed with low-grade PMP with intraductal papillary mucinous carcinoma. Recurrence was discovered 68 months after surgery, and the patient died after 78 months. In case 2, a 69-year-old man was pathologically diagnosed with high-grade PMP with signet-ring cell carcinoma caused by intraductal papillary mucinous carcinoma. The patient died 8 months post-surgery. In case 3, a 77-year-old woman was pathologically diagnosed with low- grade(partially high-grade)PMP with intraductal papillary mucinous adenoma. There was a recurrence 14 months post- surgery. The patient is still alive because of systemic chemotherapy 32 months after surgery.

It is not enough to just create medical practice guidelines; they are also required to be implemented into practice. Therefore, we surveyed specialists to determine the extent of the dissemination of the "HAM Practice Guidelines 2019," to quantify gaps, identify challenges, and understand needs in daily practice. The survey also revealed that the 25% of the specialists were unaware of the tests required for confirming human T-cell leukemia virus type I (HTLV-1) infection. Additionally, they had insufficient knowledge of the HTLV-1 infection. About 90.7% of the specialists agreed with the policy of determining treatment intensity based on disease activity. However, the implementation rate of cerebrospinal fluid marker measurement, which is useful for this assessment, was as low as 27%. Hence, it is important to use the findings of this study to further promote awareness about this issue.

We herein report a case of penile pyoderma gangrenosum that was successfully treated with prednisolone and by urethrocutaneostomy without penectomy. A man in his 50s visite dour department because of painful urination. Pyuria and redness of the external urethral meatus were present. Treatment for urethritis with antibiotics did not improve his symptoms, and a painful ulcer and fistula formation between the glans and urethra subsequently developed. Microbiological cultures revealed no growth, and punch biopsy showed only nonspecific inflammation, leading to a diagnosis of penile pyoderma gangrenosum. We initiated prednisolone (PSL) at 40 mg once daily following placement of an indwelling suprapubic cystostomy tube for dysuria. However, the treatment was ineffective. Therefore, the dosage of PSL was increased to 65 mg once daily. The ulcer disappeared， but urethral stricture remained. Six hundred days after PSL treatment, we performed urethrocutaneostomy. The patient became free of the cystostomy and was able to urinate spontaneously. In recent years, there has been an increasing number of reports of penile preservation in the treatment of penile pyoderma gangrenosum, but knowledge regarding which patients require urethral surgery is lacking. Urologists should keep in mind increased susceptibility to infection, pathergy and possible recurrence, when considering urethral surgery for penile pyoderma gangrenosum.

A 47-year-old man who was previously hospitalized three times due to bacterial meningitis experienced a headache and posterior neck pain in May. He was admitted to our hospital because of a fever 3 h later. He was fully conscious and febrile, with a headache and signs of meningeal irritation. A cerebrospinal fluid examination showed an increased number of cells with polynuclear cell predominance and decreased glucose levels, leading to the diagnosis of bacterial meningitis. Steroid and antibiotic treatment was initiated, at which time, large amounts of nasal discharge were observed. Cisternal scintigraphy was performed, and cerebrospinal fluid was detected in the nasal discharge. The cause was idiopathic, and endoscopic repair was performed. The nasal fluid leakage was suggested to be the cause of the recurrent bacterial meningitis in this case.

We conducted a retrospective review of 16 patients who were diagnosed with enterovesical fistula in our hospital between January 2000 and July 2013. The patient's median age was 74 years old and 4 were female. Most of the chief complaints were pneumaturia and fecaluria. There was a vesicosigmoidal fistula in 12 patients, an ileovesical fistula in 2, and a rectovesical fistula in 2. The main underlying cause was diverticulitis in 9 patients and a sigmoid colon carcinoma in 3. Diagnoses were made based on the findings of cystoscopy, barium enema, abdominal computed tomography and so on. Treatment varied in each case depending on the etiology and the patient's condition. The procedure was mostly open surgery, but laparoscopic sigmoidectomy was performed preserving the bladder in the two most recent cases.

Gastric adenosquamous carcinoma is a rare malignancy with a poor prognosis. We recently performed palliative gastrectomy for a gastric adenosquamous carcinoma with peritoneal dissemination and provided a course of systemic chemotherapy with S-1 plus paclitaxel(PTX)after the surgery. No serious adverse events were observed, and treatment with S-1 plus PTX was continued for 1 year before being switched to adjuvant chemotherapy with S-1 alone for another year. The tumor maker levels normalized within 2 months of the initial treatment, and the peritoneal dissemination could no longer be detected by abdominal computed tomography(CT). The patient remained in clinical remission and maintained long-term survival of over 8 years.

A case of granuloma which developed following a subcutaneous injection of leuprorelin acetate is presented. A prominent induration developed at the site of injection with a three-month type preparation, and radical retropubic prostatectomy and simultaneous excision of the granulomas were requested by the patient since they were large, infectious and painful. Our experience may indicate the necessity of conversion from leuprorelin acetate to other drugs (e.g., goserelin acetate, castration) if a local induration, caused by a subcutaneous injection of leuprorelin acetate, has developed to a large granuloma.

A 24-year-old woman with atopic dermatitis was admitted to our hospital with fever. Echocardiography showed a huge vegetation attached to the posterior mitral commissure without mitral valve dysfunction. Blood culture identified methicillin-sensitive Staphylococcus aureus. The serum level of antiphospholipid antibody was elevated. A splenic infarction occurred on the second hospital day. Surgery to resect the residual mobile vegetation was performed uneventfully on the 6th hospital day. The postoperative course was uneventful, and the patient was discharged after 4 weeks of antibiotic therapy. Preservation of the mitral valve is rare in the face of virulent Staphylococcus infection and the presence of a huge mobile vegetation. These findings were apparently related to the high serum level of infection-related antiphospholipid antibody and atopic dermatitis.

A hundred and nine cases of cecovesical fistula are described in the literature. Although its origin is usually reported to be appendicitis, we present a rare case of cecovesical and rectovesical fistulas secondary to mucinous adenocarcinoma of the cecum. An 84-year-old man was referred to our hospital with the chief complaints of fever and cloudy urine. An enterovesical fistula was seen on cystography, and cystoscopy showed a lot of mucinous fluid in the bladder and the papillary tumor arising from the enteric mucosa was identified through the fistula. Transurethral biopsy of the tumor revealed a mucinous adenocarcinoma of suspected colonic origin. At the operation, cecovesical and rectovesical fistulas secondary to cecal tumor were removed by right hemicolectomy, low anterior resection of the rectum and partial cystectomy.

A 26-year-old man was referred to our hospital for further evaluation of a cystic lesion in the pelvis. He was completely asymptomatic, although he experienced gross hematuria 10 months before his visit. Drip infusion pyelography (DIP) and abdominal computerized tomography (CT) showed a cystic structure behind the bladder and absence of the left kidney. Transrectal ultrasonography (TRUS) suggested left ejaculatory duct obstruction and seminal vesicle deformity. On cystoscopy a large bulging mass under the left side of the bladder was seen. The left half of the trigone and left ureteral orifice were absent. Vasovesiculography demonstrated dilated and tortuous left seminal vesicle. Three days after this procedure, the patient suffered left epididymitis. It did not respond rapidly to antibiotic therapy, so percutaneous drainage of the cyst was performed. He has been completely free of symptoms and no seminal vesicle cysts have been detected on TRUS at five months follow-up.

The effects of partial zona dissection (PZD) were investigated in mouse in vitro fertilization (IVF) with an oligospermic model and then PZD was applied to patients with severe male infertility. Micromanipulated (PZD-treated) and zona-intact (control) mouse oocytes were inseminated with 1 x 10(4) (low sperm concentration) and 1 x 10(5), 1 x 10(6) (normal sperm concentration) motile sperm/ml. In mouse IVF with 1 x 10(4) sperm/ml, the fertilization rate in those PZD-treated were significantly higher than that in the control (21.3% vs 8.1%, p < 0.01). No polyspermy was observed. No significant difference in the rate of development to the blastocyst stage was seen between the PZD-treated and the control (71.0% vs 65.0%). The incorporation rate of 3H-leucine in embryos at the 2-cell and blastocyst stages also did not differ between the two groups of mice. Sixteen patients with severe male infertility who had failed to fertilize for the previous three consecutive IVF cycles were enrolled in the PZD protocol. The fertilization rate in PZD-treated cycles was significantly improved (19.6% in PZD-treated vs 0% in control cycles, p < 0.001). In ten patients who underwent replacement with PZD-treated embryos, one biochemical pregnancy occurred. The present study suggests that although PZD is useful for severe male infertility, further investigation is needed to evaluate PZD in assisted fertilization.