This paper examines Harrodian instability by using the model in which a representative firm maximizes its own profit rate taking a subjective demand function into account. The subjective demand function considered by the firm contains the aggregate demand of economy as an important parameter. This implies that the firm would pay attention to the economic state as a whole. The analysis based on this model shows that its stationary state can be asymptotically stable or there can exist closed cycles around the stationary state in spite of Harrodian investment behavior. Applying the Hopf bifurcation theorem we can demonstrate such character of the dynamic system considered in this paper. Disequilibrium may take place at the stationary state, hence, we call the fluctuation "quasi growth cycle."

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A 37-year-old man involved in a motor vehicle accident was admitted to our hospital with disturbed consciousness. Computed tomography (CT) showed an acute, right-sided epidural hematoma and pneumocephalus. Emergency evacuation of the acute epidural hematoma was carried out, and his condition gradually recovered. However, cerebrospinal fluid (CSF) rhinorrhea continued despite conservative treatment. Three-dimensional reconstructed CT revealed a bone defect, which was approximately 20 mm in size, in the planum sphenoidale and tuberculum sellae, and magnetic resonance imaging demonstrated a traumatic meningo-encephalocele through the defect, with CSF collection in the sphenoid sinus. Endoscopic endonasal transsphenoidal surgery was performed. The 9-mm diameter dural defect was clearly visualized in the sphenoid sinus and was reconstructed with a combination of suturing and overlay with abdominal fascia, and absorbable polyglycolic acid felt. The CSF leakage from a traumatic meningo-encephalocele through the planum sphenoidale was successfully repaired by endoscopic endonasal surgery. Thorough preoperative evaluation of the feasibilities of the endoscopic and transcranial approaches should be based on the preoperative identification of the fistula, the bone defect, and vital structures.

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Here we describe the procedures of endoscopic pituitary and skull base surgery in our institute. We also review the literature to reveal recent advances in this field. Endonasal approach via the sphenoid ostium was carried out for pituitary lesions without the nasal speculum. Postoperative nasal packing was basically not needed in such cases. For meningiomas, craniopharyngiomas, and giant pituitary adenomas, which required intra-dural procedures, nasal procedures such as middle nasal conchotomy and posterior ethmoidectomy, and skull base techniques such as optic canal decompression and removal of the planum sphenoidale were carried out to gain a wider operative field. Navigation and ultrasonic Doppler ultrasonography were essential. Angled endoscopes allowed more successful removal of tumors under direct visualization extending into the cavernous sinus and lower clivus. If cerebrospinal fluid (CSF) leakage occurred during operation, the dural opening was covered with a vascularized mucoseptal flap obtained from the nasal septum. Lumbar drainage system to prevent postoperative CSF rhinorrhea was frequently not required. Angled suction tips, single-shaft coagulation tools, and slim and longer holding forceps, all of which were newly designed for endoscopic surgery, were essential for smoother procedures. Endonasal endoscopic pituitary surgery allows less invasive transsphenoidal surgery since no postoperative nasal packing and less dependence on lumbar drainage are needed. Endoscopic pituitary surgery will be more common and become a standard procedure. Endoscopic skull base surgery has enabled more aggressive removal of extrasellar tumors with the aid of nasal and skull base techniques. Postoperative CSF leakage is now under control due to novel methods which have been proposed to close the dural defect in a water-tight manner. Endoscopic skull base surgery is more highly specialized, so needs special techniques and surgical training. Patient selection is also important, which needs collaboration with ear, nose, and throat specialists. As a safe and successful procedure in skull base surgery, this complex procedure should be carried out only in specialized hospitals, which deal with many patients with skull base lesions.

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Fifteen abnormal hemoglobins which cause or may cause erythrocytosis are reviewed. Their clinical expression is a benign hereditary polycythemia which affects only erythrocytes. Abnormally high oxygen affinity of hemoglobin causes diminished oxygen supply to the tissue, and this in turn stimulates erythropoietin production by the kidneys resulting in increased erythropoiesis in the bone marrow. Hb Hiroshima is discussed first as a representative case, and the functional characteristics of such abnormal hemoglobins are explained in relation to their structural abnormality or a single amino acid substitution. Importance of blood oxygen affinity as a screening test for abnormal hemoglobin in erythrocytosis or anemia is stressed.

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A 38-year-old woman presented with a case of post-traumatic ethmoidal cerebrospinal fluid (CSF) leak that was repaired using a purely endoscopic endonasal approach. Six weeks after a mild domestic maxillofacial trauma, she started complaining of clear, watery discharge from the left nostril and headache. Neuroimaging investigations disclosed a linear fracture of the left anterior ethmoidal roof without evidence of large bony breaches or any brain tissue damage. After conservative medical treatment with carbonic anhydrase inhibitors failed, she was referred to our hospital for surgical repair of the osteodural defect. An endoscopic endonasal transethmoidal approach was successfully performed, and an overlay technique was used to reconstruct the defect. The patient was discharged without clinical evidence of CSF rhinorrhea and no leaks were apparent at the 3-month follow-up clinical and radiological examinations. Post-traumatic CSF rhinorrhea occurs in cases of dural tears associated with small bone breaks, most frequently involving the anterior skull base. Recovery is often spontaneous following only bed rest, or with medical treatments such as inhibitors of carbonic anhydrase diuretics, steroids, or eventually stool softeners to help reduce CSF pressure. Surgical repair is required when first-line conservative treatment proves ineffective. The present case shows that the endoscopic endonasal technique for the management of CSF leaks provides a less invasive surgical route to achieve valid dural repair.

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This work describes the design, synthesis, AChE inhibitory activity, and structure-activity relationship of compounds related to a recently discovered series of AChE inhibitors: phthalimide alkyloxyphenyl N-methylcarbamates. The influence of structural variations on inhibitory potency was carefully investigated by modifying different alkyloxy chain lengths and positions between phthalimide and phenyl N-methylcarbamate. The biological properties of the series were investigated in some detail by considering their activity on isolated enzymes. All of the newly synthesized derivatives, when tested on isolated AChE from the brain of the housefly (Musca domestica), were more active than phenyl N-methylcarbamate. In particular, compound I1 displayed the best AChE inhibition (352-fold higher than phenyl N-methylcarbamate, and 29-fold higher than metolcarb), which suggested that the phthalimide group of I1 bound strongly to the residues lining the gorge, and phenyl N-methylcarbamate bound at the catalytic sites.

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The Atacama Kozan Mine is located in the Candelaria-Punta del Cobre district which is known to host IOCG type ore deposits. The ore deposit of the mine lies at 300m-400m below the surface and it is completely a concealed ore deposit.
The Nittetsu Mining Co., Ltd. has conducted exploration work in the area consisting of surface geological surveys, geophysical surveys and drilling surveys in order to develop the Atacama Kozan Mine.
In the early days of the exploration the ore deposit type to be expected in this area was thought to be of breccia (vein) type from the analogy to the deposits of the Socavon Mine and the Carola Mine just across to the east of the valley. But as the drilling survery went on, frequent occurrences of layered copper ore accompanying abundant, magnetite were recognized from a certain horizon of the strata and a horizontally elongated shape of the ore body was implied by subsequent geophysical surveys such as CSAMT, TDEM, and PEM logging survey. So the target ore deposit type was modified to the one composed of strata-bound (manto) ore deposit although it was still in an early stage of the exploration.
Based on this ore deposit model, an exploration tunnel was excavated and drilling surveys were conducted both from the surface and the underground. Consequently an ore reserve of 30 million tons (with the recoverable ore of 20 million tons) at the copper grade of 1.5% was discovered and finally the Atacama Kozan Mine was developed.

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This is a report to describe the procedure of the endoscopic endonasal skull base reconstruction using a vascularized nasoseptal flap. Between November 2008 and October 2009, 22 patients underwent reconstructions using a nasal septal flap combined with a balloon catheter (flap group) for closure of large dural defects after the endoscopic endonasal skull base approaches. The method is as follows; We start to harvest the nasal septal flap as a mucoperichondrial flap based on the posterior septal branch of sphenopalatine artery. The middle nasal turbinate is usually dissected. The first incision is the anterior vertical incision made with unipolar electrocautery at the intercutaneomucous point of the nasal vestibule. The second incision is made the along the floor of the nasal cavity from the choana to the location of the initial anterior incision. Thereafter, the superior incision to the sphenoid ostium is made 1.0∼1.5cm below the most superior aspect of the nasal septum. The pedicle of the flap formed in the width from the sphenoid ostium to the choana is extended laterally to the level of the sphenopalatine foramen. The nasal septal flap is usually placed in the nasopharynx until using in later reconstruction. On the reconstruction phase, the nasal septal flap is laid directly on the large dural and bony defect and fat grafts are applied outside with fibrin tissue glue. A Sinus balloon catheter is finally placed as support for 7∼10 days. Otorhinolaryngological endoscopic assessments are regularly performed at outpatient clinics.
Postoperative CSF leaks occurred in two patients (9.1%) Conclusions: Our endoscopic endonasal skull base reconstructions using a nasal septal flap combined with a balloon catheter are useful and reliable for ventral skull base defects after endoscopic endonasal approaches.

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Efficient routes to various kinds of heterocycles incorporating the p-halophenyl moiety have been synthesized. Different pyrrole derivatives have been synthesized, as well, by Thorpe–Ziegler cyclization. Therefore, we synthesized different analogues of tacrine by Friedländer reaction of o-amino nitriles (pyrazolo, furano and pyrrolo) with different cycloalkanones. The use of microwave irradiation leads to shorter production times and high product conversion. These synthesized compounds were biologically evaluated by Ellman’s test on acetylcholinesterase inhibition.

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Skull base reconstruction after an endoscopic endonasal approach into the cerebrospinal fluid (CSF) space is always challenging. Various reconstructive methods are available, but no standard technique is established. This report describes the endoscopic skull base dural closure using a modified nonpenetrating clip device with shaft length of 15 cm. Six patients with an intra-suprasellar or suprasellar tumor who underwent extended endoscopic endonasal transsphenoidal surgery were targeted. For closure of the skull base dural defect after tumor removal, fascia lata was first placed as an inlay graft and was subsequently fixed with the dura using a modified nonpenetrating clip device. No CSF leakage from the closed dura with an inlay fascia lata fixed with clips was confirmed by the Valsalva maneuver. To complete skull base reconstruction, fascia lata was then positioned as an overlay graft and covered with vascularized pedicled nasoseptal flaps. Five of six patients experienced no CSF rhinorrhea postoperatively. The modified nonpenetrating clip device may achieve effective dural closure in the deep and narrow nasal cavity. We introduce this clip device technique as one of the endoscopic skull base dural closure methods.

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Background: Little is known about the characteristics of emergency patients transported to hospital while participating in sports activity. Hence, we identified characteristics of emergency patients transported to hospital by emergency medical service (EMS) while participating in sports activity in Osaka City.

Methods: Population-based ambulance records of Osaka Municipal Fire Department were reviewed. All sports-related emergency transport cases (ie, patients experiencing external injury or illness during/immediately after participation in sports activity and then transported to hospital by the EMS) were enrolled, including both athletes and recreational sports participants. The study was performed from January 1, 2013 to December 31, 2015. Data of patient characteristics were described according to the type of sports.

Results: During the study, 661,190 patients required emergency transport in Osaka city; 2,642 (0.4%) were sports-related emergency transport, including 2,453 external injuries and 298 illnesses. Overall, 79.0% of patients were men and 44.4% were less than 18 years. Emergency transport during ball games accounts for the majority of cases (71.5%, 1,888/2,642), including baseball (n = 380), soccer (n = 368), and futsal (n = 209). The leading diagnosis/symptom of external injury was fracture/bone contusion (n = 701) and that of illness was heatstroke/dehydration (n = 184). Serious acute illness, such as sudden cardiac arrest, accounted for 0.6% (16/2,751) of all accidents, with half of them (n = 8) related to long-distance running.

Conclusion: Characteristics of sports-related accidents widely varied by type of sports. Measures to prevent serious accidents during sports activities should be established based on the information on patient characteristics of each type of sports.

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