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This study proposes a novel method for managing surplus soil in urban construction projects by investigating the use of banana leaf powder (BLP) as an eco-friendly and efficient mud-soil stabilizer. This study is pioneering in its focus on the use of an agricultural waste product, BLP, as an alternative to conventional methods that frequently rely on cement or lime, which pose environmental concerns owing to their high alkalinity and carbon emissions. BLP, derived from dried and pulverized banana leaves, traditionally used in various industries, was evaluated for its suitability as a stabilizer against orange peel biopolymer (OBP) and fly ash (FA). The findings of this study are groundbreaking. BLP's water absorption capacity, Wab, although lower than that of OBP, was significantly higher than that of FA, demonstrating its potential as a mud soil stabilizer. BLP increased the compaction and strength of the treated clay, whereas OBP made it more challenging to compact the clay owing to gelatinization. The ease of compaction with BLP is attributed to the absorption of free water into the pores of the particles. These results suggest that differences in the stabilizer's water absorption mechanism affect the effectiveness of the post-treatment compaction process on the treated soil. An analysis of the impact of water absorption capacity on the cone index, qc, revealed a material-independent relationship between the parameter β (=Wab × A, where A denotes stabilizer addition content) and qc for BLP and FA. This is because, in contrast to OBP, BLP and FA did not gelatinize the free water that was not absorbed by the stabilizer and remained in the same form within the treated clay. This indicates that understanding the water absorption capacity and mechanism of organic- or inorganic-based stabilizers is important for predicting the strength of treated soil. The same relationship between β and qc holds true for the hybrid-treated clay using both BLP and FA, with β considered to be the sum of β for both BLP and FA. Furthermore, this study innovatively addresses the concern of BLP decay in treated soil by creating a hybrid stabilizer with FA and conducting experiments to accelerate BLP decay using fungal mycelia. These experiments revealed that the hybrid-treated clay exhibited a more gradual decrease in carbon content and stabilized pH levels, implying that FA could inhibit decay by fungal mycelia, improving the BLP-treated soil's long-term durability. These findings suggest that agricultural wastes with high organic content can be effectively used for soil stabilization and ground improvement in civil engineering construction and maintenance projects by combining inorganic materials and taking advantage of their properties, such as high water absorbency. This can address the issues (such as high alkalinity and high carbon dioxide emissions) associated with cement- and lime-based stabilizers, which were previously widely used.

This study aimed to address and overcome the inherent challenges associated with the influence of primary curing on the consistency, compaction, and strength attributes of clays treated with biomass ash, specifically palm kernel shell ash (PKSA) and rice husk ash (RHA), for stabilization. Primary curing refers to the time from the addition of PKSA or RHA to the clay until its use for fill or backfill purposes. This study explores the effect of curing on the water absorption capacities of PKSA and RHA to elucidate the treatment mechanisms that shape the characteristics of the treated clays. Wab, which is the amount of water absorbed by 1 g of each stabilizer, was determined using the suction filtration technique. PKSA exhibited a significant increase in Wab with an increase in the curing period t. Wab of RHA showed no significant variation with t. The water absorption mechanisms of each stabilizer were successfully demonstrated using scanning electron microscopy (SEM) images and X-ray diffraction (XRD) patterns. It was also observed that the impact of primary curing on the limit states, compaction, and strength of the clays treated with PKSA and RHA differed significantly. The observed differences are consistent with the variation in Wab with respect to t between PKSA and RHA. The test results also suggest that changes in the free water content of the clays owing to water absorption by PKSA and RHA are closely related to changes in the properties of the PKSA- and RHA-treated clays. Parameter β represents the product of Wab and the addition ratio of each stabilizer, A, relative to the mass of the dry clay. The contributions of β to the limit states, compaction, and strength attributes of PKSA- and RHA-treated clays were much more significant than those of A.

Major challenges are encountered when using high-water-content clays as construction materials owing to their low shear strength and high compressibility. Processes, such as sun drying and stabilization using chemical agents, can address the problems met with these clays during their conveyance and reuse. However, natural dehydration is a time-consuming process, and chemical stabilization can lead to an increase in the hydrogen ion index (pH) of the surrounding environment. Thus, the aim of this study is to improve the performance of high-water-content clay using a combination of green and byproduct materials, specifically bamboo chips and fly ash, which are cost-effective and eco-friendly. No previous study has attempted to design a mixture for the purpose of improving the performance of clay based on the water absorption and retention performance of stabilizers. In this study, the water absorption and retention rate (Wab), which is the mass of the water absorbed and retained by 1 g of each stabilizer, was measured by removing the unabsorbed and unretained water through filtration under vacuum suction. A series of Cone Index tests were conducted on clay, separately treated with bamboo chips and fly ash, and the tests demonstrated a correlation among the Cone Index (qc), Wab, and amount of stabilizer added (Ast). A novel mixture design was proposed for hybrid-treated clay, using the two types of stabilizers in the composite, based on parameter β, which is defined as the sum of the product (Wab/100)×(Ast/100) of each stabilizer used in the hybrid-treated clay. The results of the Cone Index tests performed on the hybrid-treated clay showed that the proposed mixture design can predict the combinations of certain amounts of each stabilizer needed to attain the target qc with minimal errors. The results of pH measurement tests indicated that the hybrid-treated clays produced by the proposed mixture design were more eco-friendly than fly ash-treated clays. Furthermore, the theoretical maximum CO2 fixation capacities of the hybrid-treated clays were evaluated to assess their feasibility as CO2-fixing materials.

In this study, a novel testing method was developed to evaluate the water absorption and retention of waste-based stabilizers using suction filtration. Suction filtration was seen to remove most of the unabsorbed and unretained water from the waste-based stabilizer without losing any waste-based stabilizer particles. Therefore, oven-drying of the wet stabilizer, which can deteriorate the stabilizer, was not necessary. In addition, a formula was introduced to estimate the residual free water in the stabilizer after suction filtration based on the particle size. This estimate was used as a correction to determine the water absorption and retention rate (Wab) of the stabilizer. Subsequently, newly developed tests were conducted on fly ash (FA), a paper sludge ash-based stabilizer (PSAS), biomass ash (BMA), and the PSAS–BMA hybrid to evaluate Wab. The results show that the PSAS exhibited the highest Wab, followed by the BMA and FA. This is attributed to the CaO content of each stabilizer, which may have initiated hydration reactions. The Wab of the PSAS–BMA hybrid was similar to that of the PSAS, which is attributed to the synergistic effects of the components of each type of waste. Finally, the strength development of the FA, PSAS, BMA, and PSAS–BMA hybrid-treated clays was investigated via cone index tests. In addition to the stabilizer addition ratio (A), the Wab of the stabilizers is suggested to be an essential indicator for predicting the strength development of clays treated with waste-based stabilizers. Parameter β, which is the product of Wab and A, governs the cone index qc of the treated clays instead of A and Wab. Thus, the modified water content, w*, which considers the absorbed and retained water as a solid instead of a liquid, was applied to the cone index test results. The results show that the qc of the treated clays is more correlated to w* than to the measured water content. An empirical relationship for predicting cone index qc using w* was also proposed.

In an attempt to reduce environmental impact, paper sludge ash (PS ash) has recently been studied for its complementary reuse with cement for soil stabilization. In order to establish the optimal mixture design for combining PS ash and cement in soils, a detailed investigation into the stabilizing mechanism is required. To assess the combined effects of PS ash and cement on the strength development of stabilized clay soil, referred to as PS ash–cement-treated clay, a new critical parameter, the unabsorbed and unretained clay-water/cement ratio W*/C, was proposed. To determine W*/C, a new testing method for evaluating the water absorption and retention performance of PS ash was developed. It was revealed that the water absorption and retention rate Wab of PS ash increased with curing time. Unconfined compression tests conducted on the PS ash–cement-treated clay with various water-cement–PS ash mixture proportions and different curing times affirmed that the strength development was fundamentally governed by the parameter W*/C. This suggests that the water absorption and retention rate Wab obtained by the developed method is an essential material parameter in the mixture design for the PS ash–cement-treated clay. It was also found that the effect of the hybrid treatment method, which uses both cement and PS ash, was better than that of the method which uses cement alone, particularly under high W*/C conditions. This indicates that the water absorption and retention performance of PS ash can be fully utilized when the mixture has sufficient unabsorbed and unretained water for cement hydration.

We experienced a case of traumatic cardiac contusion accompanied by the rupture of the pericardium after multiple blunt trauma sustained in a traffic accident. A 26-year-old woman who had suffered from blunt chest and abdominal trauma was admitted to our hospital, being unconscious with multiple severe injuries including pelvic fracture, bilateral hemothorax, and multiple fractures in the extremities. The patient was in a shock status. We performed the transcatheter arterial embolization of the internal iliac arteries to control the bleeding, when aortography showed that the contrast media extravasated toward the left thoracic cavity. Immediately, an operation for blunt chest trauma was performed. Blood was flooding out of the ruptured pericardium because of the contusion of myocardium. The postoperative course was uneventful. Blunt chest trauma is usually accompanied by multisystem injury. Therefore, it is imperative to determine the priority of treatment based on preoperative examination in patients having multiple injuries.

We tested the hypothesis that chronic hypercapnia contributes to the development of core/targetoid fibers in ventilatory muscles. Five Wistar rats were kept in 5% CO2 in air for 13 weeks. Arterial blood gases (mean +/- SE) were pH 7.402 +/- 0.017, PaCO2 47.4 +/- 2.4 Torr, and PaO2 105.2 +/- 13.2 Torr. While the rats were chronically hypercapnic, their mean minute ventilation was about 1.7 times higher than that of rats that breathed air. This level was maintained throughout the exposure to CO2. Approximately 6% to 12% of the diaphragmatic type-I fibers were replaced by core/targetoid fibers in 3 of 5 chronically hypercapnic rats but not in the 3 control rats. Chronic hypercapnia may have continuously stimulated the respiratory center and resulted in more work done by the ventilatory muscles. Long-term overuse of the ventilatory muscles, which may occur in patients with chronic respiratory failure, can cause morphological changes in type-I fibers in the diaphragm.

We describe a case in which a left ventricular-coronary sinus communication through a dissecting ventricular septal aneurysm developed after a redo mitral valve replacement. The outlet orifice of the communication was located in the side wall of the ostium of the coronary sinus. Both the communication and the aneurysm were successfully dealt with by performing a right atriotomy and by opening the aneurysm from its outlet orifice.

Anticardiolipin antibody (aCL) is considered to be one of the contributory factors in the development of cerebral infarction. We compared the recurrence and prognosis of 20 ischemic stroke patients with positive IgG aCL who had no collagen vascular diseases with those in 120 patients with negative IgG aCL. The aCL-positive patients comprised 18 females and 2 males aged 43-79 (mean 64) years and the mean follow-up period was 5.6 years. The aCL-negative patients comprised 82 males and 38 females aged 40-84 (mean 64.2) years and the mean follow-up period was 5.8 years. There was no significant difference in age and mean follow-up period between the two groups. We examined the recurrence rate and the intervals from the onset to the recurrence in both groups. We investigated the relationship between the recurrence of stroke and chronological changes in titer of aCL in patients with positive aCL. We also evaluated the effectiveness of antiplatelet agents for the prevention of recurrent stroke in both groups. A positive aCL level was defined as one which was > 3 standard deviations (S.D.) above the mean level for normal controls. A high titer of aCL was defined as being > 7 S.D. above the normal mean value. Among the 20 patients with positive aCL, recurrence of ischemic stroke occurred in 10 (50%) (cerebral thrombosis in 8 and cerebral embolism in 2) and myocardial infarction developed in 2 patients. As regards the number of ischemic episodes of stroke, recurrence occurred twice in 4 and once in 6 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

A 43-year-old woman had noticed muscular weakness in her arms for four years before her admission. Muscle weakness and atrophy were prominent in the bilateral deltoid muscles, but muscular strength was almost unimpaired in the bilateral forearms and intrinsic muscles. There was no sign of sensory impairment except vibratory sensation. EMG revealed neuropathic NMU. X-P of the cervical spine showed enlargement of the spinal canal diameter, and MRI of the spinal cord revealed a large syrinx. On the basis of metrizamide CT and cranial MRI, a diagnosis of syringomyelia with Chiari malformation (type I) was made. Despite the presence of a large syrinx extending from C 1 to Th 11, the only detectable neurological sign was proximal weakness of the upper extremities simulating myopathy.

We reported an autopsy case of a 14-year-old girl with cardiac myxoma, presenting sudden onset of consciousness disturbance and right hemiplegia while running in an 800 meter race. Though CT scan showed no abnormal findings, cerebral angiogram revealed an embolic stenosis of the left middle cerebral artery, and abdominal aortogram showed complete obstruction of the bilateral common iliac artery. Histological study of emboli taken from obstructed femoral arteries showed systemic embolization of the cardiac myxoma. She died three days after admission. Autopsy was performed. Myxoma tissue was not found, but its stalk was left in the left atrial septum. The brain was very edematous, and a myxoma emboli was found in the left middle cerebral artery. Systemic embolization of myxoma to spleen, kidneys, liver, pancreas, etc. was found histologically. Left atrial myxoma is a rare but potentially treatable cause of stroke, and should be included in the differential diagnosis of cerebral vascular disease, especially in young patients.

Although tubular aggregates (TAs) are nonspecific findings observed in various neuromuscular disorders, they are specifically recognizable in the muscles of patients with periodic paralysis. However, their function and significance are still unknown. We have previously reported that TAs were observed in normal male, but not in female mouse muscles. To clarify the effects of sex hormones on morphogenesis of TAs, the following studies were performed. In normal male mice (ICR/JCL, N = 102), TAs began to appear at 3-4 months, and were seen in all animals above 6-7 months of age. On the other hand, in normal female mice (N = 50), TAs were observed in only 2 mice, at 14 and 18 months of age. When mice were castrated (N = 69: male 34/female 35), TAs were not found in either males or females. The results suggested that there is a close relationship between TA formation and male hormone. Testosterone propionate (TP) was administered to both castrated and un-castrated mice (N = 167: male 84/female 83). TAs were not found in castrated, TP 10 mg/2M implanted mice (N = 22: male 12/female 10). When TP was increased to 20 mg/1M, TAs began to appear in both male and female, castrated and un-castrated mice at 3 months, and were observed in 100% of mice, except female un-castrated mice, older than 4-5 months of age. Accordingly, a fairly large amount of TP above a certain threshold and a long incubation time of at least 3 months is necessary to induce TAs in the skeletal muscle.(ABSTRACT TRUNCATED AT 250 WORDS)

Two patients with life-threatening respiratory insufficiency resulting from tracheobronchial compression by expanding aneurysms of the ascending aorta and innominate artery were successfully treated by cardiopulmonary bypass, even in the presence of significant aortic regurgitation. The pertinent surgical procedures are described.

Eighty-seven patients with isolated ventricular septal defect (VSD) operated on in the first 5 years of life, that had a mean interval of 10 months between diagnostic catheterization and surgery, were studied retrospectively. The size of the VSD was correlated with diagnostic catheterization data and comparative analysis of clinicl findings (ECG and CTR) was made between the time of diagnostic catheterization and just prior to surgery. The study showed that 42 per cent of patients with the ratio of systolic pulmonary artery pressure to systolic systemic artery pressure (Pp/Ps) 0.5 to 0.8 had a marked reduction in size of VSD in a rather short interval of 10 months. In patients with Pp/Ps greater than or equal to 0.8, the incidence of decrease in VSD size was close to nil. The highest incidence of decrease in VSD size was seen in patients with high flow and low resistance. ECG and CTR were very useful diagnostic tools to follow the course of the VSD size. The patients with Pp/Ps 0.5 to 0.8 should be observed for an interval of 10 to 12 months, expecting spontaneous decrease in VSD size. If clinical parameters (ECG, CTR) fail to improve in that interval, then the patients should have surgery. The patients with Pp/Ps greater than or equal to 0.8 should be operated on without delay.

Cardiodynamic effects of acute experimental right bundle branch block (RBBB) were studied in canine hearts: group A included 15 normal hearts; group B-1 had seven hearts with mild right ventricular hypertrophy (RVH), and group B-2 had 11 hearts with marked RVH. The main sequential changes following RBBB were marked prolongation of the Q upstroke interval of the right ventricle and striking shortening of right ventricular systolic time that affected right and left ventricular interaction, particularly in the hearts with RVH. Hemodynamic changes were: the right ventricular end-diastolic pressure was elevated markedly (4.4 +/- 2.2----9.8 +/- 2.6 mm Hg, p less than 0.001) in group B-2, moderately (p less than 0.01) in group B-1, and not at all in group A. The right ventricular positive peak dp/dt decreased remarkably (1036 +/- 151----827 +/- 152 mm Hg/sec, p less than 0.001) in group B-2 and negligibly in the other groups. A significant correlation existed between the percentage of decrease in right ventricular peak dp/dt and the QRS duration of RBBB in each group (p less than 0.01). The left ventricular peak negative dp/dt decreased distinctly (2570 +/- 326----+/- 2055 +/- 362 mm Hg/sec, p less than 0.01) in group B-2 and not at all in the other groups. The stroke volume showed 12% decrease in group B-2 (p less than 0.001), 8% decrease in group B-1 (NS), and no decrease in group A. In the presence of RVH, acute RBBB causes significant impairment of right and left ventricular function. The magnitude of the impairment invariably depends upon both the prior degree of RVH and the width of the QRS complex.

A randomized, prospective study of the effectiveness of preoperative administration of coenzyme Q10 on the prophylaxis of postoperative low cardiac output state was performed in 50 patients with acquired valvular diseases necessitating valve replacement. There were 25 patients in the treatment group and 25 in the control group. Patients in the treatment group received 30 to 60 mg of coenzyme Q10 orally for six days before operation. Preoperative clinical variables, operative procedures, total cardiopulmonary bypass time, and aortic cross-clamping time were similar for the two groups. Postoperatively, mild to severe low cardiac output state developed in 28 of 50 patients (56%) and necessitated the administration of considerable amounts of inotropic agent. The treatment group showed a significantly lower incidence of low cardiac output state during the recovery period than the control group (p less than 0.05). These results suggest that preoperative administration of coenzyme Q10 will increase the tolerance of human hearts to ischemia during aortic cross-clamping.

The influence of graded perfusion pressure (30, 60, and 90 mmHg) at cardiopulmonary bypass were studied on beating empty hearts (BEH) or spontaneously fibrillating hearts (SFH) in the normothermic state. The adequacy and distribution of coronary flow and the myocardial oxygen consumption (MVO2) were examined using the tracer microsphere technique in twelve mongrel dogs. In the SFH, the left ventricular (LV) endocardium (ENDO)/epicardium (EPI) flow ratio indicated significant decrease at 30 and 60 mmHg (0.83 +/- 0.05 and 0.86 +/- 0.06, p less than 0.005, respectively), but was recovered to control value at 90 mmHg (1.01 +/- 0.13). In the BEH, these low perfusion pressures did not result in an abnormal flow distribution in the LV (1.03 +/- 0.03 at 30 mmHg). The flow distribution to the right ventricle (RV) relatively increased in both the BEH and the SFH (p less than 0.001). The ENDO/EPI ratio of the RV did not decrease at 30 mmHg in both groups (1.11 +/- 0.03 in BEH and 1.16 +/- 0.08 in SFH). Coronary blood flow and MVO2 were significantly higher in the SFH than in the BEH. Coronary blood flow increased significantly with increase in the perfusion pressure, in both groups. The MVO2 was constant in the BEH, regardless of the perfusion pressure, but increased in the SFH at increasing pressure. These results show that in the SFH, subendocardial underperfusion of the LV is induced at the perfusion pressure of 30 and 60 mmHg.

To determine the protective effects of amino acids on the ischemic and reperfused myocardium, an experimental study was carried out. Rats were starved for 20 days, then separated into the following three groups: group I: control, group II: glutamate and aspartate were administered before aortic cross clamping for 5 minutes, and added to the cardioplegic solution, group III: glutamate and aspartate were given during the initial 15 minutes of reperfusion. After 25 minutes of equilibration, the hearts were made ischemic at 35.5 degrees C for 45 minutes, and arrested with high potassium cardioplegic solution immediately after aortic cross clamping. The recovery of cardiac output in group II was significantly (p less than 0.05 vs group I & III) better than that in groups I and III, with no difference between groups I and III. Tissue analysis for high energy phosphate compounds revealed that the levels of ATP and total adenine nucleotides were significantly (p less than 0.05 vs group I & III) higher in group II. Lactate output during the initial three minutes of reperfusion was decreased to the greatest extent in group II. Metabolic studies involving the examination of oxygen utilization also revealed no differences between groups I and III. Thus, addition of glutamate and aspartate before and during aortic cross clamping is effective for reducing ischemic damage, however, the administration of these amino acids during the reperfusion is without significant effects.