99 research outputs found
Flight Performance of the AKARI Cryogenic System
We describe the flight performance of the cryogenic system of the infrared
astronomical satellite AKARI, which was successfully launched on 2006 February
21 (UT). AKARI carries a 68.5 cm telescope together with two focal plane
instruments, Infrared Cameras (IRC) and Far Infrared Surveyor (FIS), all of
which are cooled down to cryogenic temperature to achieve superior sensitivity.
The AKARI cryogenic system is a unique hybrid system, which consists of cryogen
(liquid helium) and mechanical coolers (2-stage Stirling coolers). With the
help of the mechanical coolers, 179 L (26.0 kg) of super-fluid liquid helium
can keep the instruments cryogenically cooled for more than 500 days. The
on-orbit performance of the AKARI cryogenics is consistent with the design and
pre-flight test, and the boil-off gas flow rate is as small as 0.32 mg/s. We
observed the increase of the major axis of the AKARI orbit, which can be
explained by the thrust due to thermal pressure of vented helium gas.Comment: 19 pages, 10 figures, and 6 tables. Accepted for publication in the
AKARI special issue of the Publications of the Astronomical Society of Japa
A Report on Hydrographic Activities Following the Great East Japan Earthquake
The Great East Japan Earthquake (Mw9.0) on 11 March 2011 accompanied with a huge tsunami of more than 10 meters in height devastated many cities and ports along the Pacific coast of northeastern Japan, and claimed nearly 20,000 lives with many of them still missing. This report reviews actions taken by the Japan Hydrographic and Oceanographic Department (JHOD) after this unprecedented disaster. Immediately after the earthquake, the JHOD carried out hydrographic surveys for the urgent need to help clear the passage in ports due to sunken debris swept away by the tsunami. These surveys have enabled the vessels with relief supplies on board for the affected areas to enter the ports. The JHOD revisited the affected ports for the next stage of hydrographic surveys. These surveys will contribute to revised nautical charts based on new data collected after the earthquake, and includes the ongoing restoration and reconstruction work of quays and port facilities. This stage includes the re-determination of the datum level of the affected ports, which is necessary because of large subsidence being reported in the areas. All of these efforts by the JHOD clearly demonstrate the significance of the hydrographic activities in case of the post-quake emergency situation, not only for the safety of navigation but also for economic recovery
Mice with defects in HB-EGF ectodomain shedding show severe developmental abnormalities
Heparin-binding EGF-like growth factor (HB-EGF) is first synthesized as a membrane-anchored form (proHB-EGF), and its soluble form (sHB-EGF) is released by ectodomain shedding from proHB-EGF. To examine the significance of proHB-EGF processing in vivo, we generated mutant mice by targeted gene replacement, expressing either an uncleavable form (HBuc) or a transmembrane domain–truncated form (HBΔtm) of the molecule. HBuc/uc mice developed severe heart failure and enlarged heart valves, phenotypes similar to those in proHB-EGF null mice. On the other hand, mice carrying HBΔtm exhibited severe hyperplasia in both skin and heart. These results indicate that ectodomain shedding of proHB-EGF is essential for HB-EGF function in vivo, and that this process requires strict control
Coexistent poorly-differentiated neuroendocrine cell carcinoma and non-invasive well- differentiated adenocarcinoma in tubulovillous adenoma of the rectum : report of a casel
A 74-years old man was referred to our hospital for treatment of a rectal mass.
Colonoscopy revealed villous tumor covering all the lower rectal lumen. Biopsy yielded
a diagnosis of adenoma. CT examination showed tumor shadows of the rectum and the
liver. Pelvic MRI examination showed a 10.5 8 7 cm tumor with high signal intensity on
the T2 weighted images in the rectum. Rectosigmoidectomy with lymph node dissection
was performed with the diagnosis of rectal cancer that metastasized to the liver. Histological
and immuno- histochemical features showed coexistent poorly-differentiated small
cell neuroendocrine cell (NEC) carcinoma and non-invasive well-differentiated adenocarcinoma
in tubulovillous adenoma. However the chemotherapy with FOLFOX and
Bevacizumab was performed postoperatively, the patient died in cancer 3 months after
surgery. Rectal poorly-differentiated NEC carcinomas are thought to be a tumor with a
high malignant potential. Recently, the UICC TNM classifications of malignant tumors,
7th edition and the Guidelines for colorectal NEC tumors of European Neuroendocrine
Tumor Society have been published. They would be evaluated, and effective multimodal
therapy for NEC carcinomas should be established
スイ カイメンジョウ リンパカンシュ cavernous lymphangioma of the pancreas ニ タイシテ フククウキョウカ シュヨウ テキシュツジュツ オ オコナッタ 1レイ
Cavernous lymphangioma of the pancreas is a rare condition, recognized as nonepithelial pancreatic cystic tumors. This is the first case report, to our knowledge, of performance of a laparoscopic excision for lymphangioma of the pancreas. A 49 year-old male presented with an enlarged cystic tumor involving the pancreas body and tail and without abdominal pain, was prepared for laparoscopic excision. The surgical specimen showed a multicystic mass measuring 7.0×5.5×3.0cm, which was diagnosed as a benign lymphangioma with cavernous features. The patient remains symptom free 4 years after laparoscopic excisio
A case of perinephric liposarcoma which recurred ten years later from the initial operation
A 58-year old man was referred to our hospital for treatment of an abdominal
mass. As for him, tumor resection with right nephrectomy had been performed ten years
ago for a giant well-differentiated perinephric liposarcoma. CT examination showed a
huge tumor shadow in the abdominal cavity. Abdominal MRI examination showed a 15 8
cm tumor with almost high signal intensity on the T2 weighted images. At lapalotomy, a
large bulky retroperitoneal tumor pointed out before an operation was found. Surgical
extirpation of the tumor was performed. Besides, several tumors of the thumb head size
were detected into right retroperitoneal fatty tissue. The right side mesocolon and the
tumors were not able to exfoliate, therefore right hemicolectomy was performed. Histological
features showed dedifferentiated liposarcoma. The postoperative course was uneventful.
But eight months after surgery, he was admitted again for treatment of a 4 3
cm retroperitoneal tumor. Extirpation of the tumor was performed. Histological finding
of this tumor also showed dedifferentiated liposarcoma. Dedifferentiation, occurring in
15% of the well-differentiated liposarcomas, sometimes may develop later. Long-term detailed
follow-up is necessary for well-differentiated liposarcoma
ジョウチョウカンマク ドウミャクセイ ジュウニシチョウ ヘイソクショウ SMA syndrome ニ タイスル フククウキョウカ ジュウニシチョウ クウチョウ フンゴウジュツ
Superior mesenteric artery (SMA) syndrome is a rare disorder, recognized as nausea, vomiting, weight loss, and postprandial abdominal pain due to compression and obstruction of the third portion of the duodenum by the SMA. If conservative treatment fails, then duodenojejunostomy or lysis of the ligament of Treitz is indicated. Recently, laparoscopic techniques have been described. This is the first case report, to our knowledge, of performance of a laparoscopic duodenojejunostomy for treatment of SMA syndrome in Japan. A 17-year-old female with a diagnosis of SMA syndrome was prepared for surgery after having failed conservative management. Laparoscopic duodenojejunostomy was performed through the mesenterium of the transverse colon. Postoperative course was uneventful. A gastografin study obtained on postoperative day 6 demonstrated no leakage of the anastomosis and free flow of contrast medium through the duodenojejunostomy. Laparoscopic duodenojejunostomy is safe and effective and a viable method for treatment of SMA syndrome
- …