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Sample records for jejunal rotation caused

  1. Primarily Proximal Jejunal Stone Causing Enterolith Ileus in a Patient without Evidence of Cholecystoenteric Fistula or Jejunal Diverticulosis

    PubMed Central

    Mneimneh, Mostapha; Hammoud, Mazen M.; Zaaroura, Ahmed; Papas, Yasmina S.

    2016-01-01

    Stone formation within the intestinal lumen is called enterolith. This stone can encroach into the lumen causing obstruction and surgical emergency. Jejunal obstruction by an enterolith is a very rare entity and often missed preoperatively. To our knowledge, most cases of jejunal obstruction, secondary to stone, were associated with biliary disease (cholecystoenteric fistula), bezoar, jejunal diverticulosis, or foreign body. Hereby we present a rare case report of small bowel obstruction in an elderly man who was diagnosed lately to have primary proximal jejunal obstruction by an enterolith without evidence of a cholecystoenteric fistula or jejunal diverticulosis. This patient underwent laparotomy, enterotomy with stone extraction, and subsequent primary repair of the bowel. PMID:27803836

  2. Phytobezoar in a jejunal diverticulum as a cause of small bowel obstruction: a case report

    PubMed Central

    2011-01-01

    Introduction Phytobezoars are concretions of poorly digested fruit and vegetable fibers found in the alimentary tract. Previous gastric resection, gastrojejunostomy, or pyloroplasty predispose people to bezoar formation. Small-bowel bezoars normally come from the stomach, and primary small-bowel bezoars are very rare. They are seen only in patients with underlying small-bowel diseases such as diverticula, strictures, or tumors. Primary small-bowel bezoars almost always present as intestinal obstructions, although it is a very rare cause, being responsible for less than 3% of all small-bowel obstructions in one series. Jejunal diverticula are rare, with an incidence of less than 0.5%. They are usually asymptomatic pseudodiverticula of pulsion type, and complications are reported in 10% to 30% of patients. A phytobezoar in a jejunal diverticulum is an extremely rare presentation. Case presentation A 78-year-old Pakistani man presented to our clinic with small-bowel obstruction. Upon exploration, we found a primary small-bowel bezoar originating in a jejunal diverticulum and causing jejunal obstruction. Resection and anastomosis of the jejunal segment harboring the diverticulum was performed, and our patient had an uneventful recovery. Conclusion Primary small-bowel bezoars are very rare but must be kept in mind as a possible cause of small-bowel obstruction. PMID:21951579

  3. Jejunal intussusception caused by a huge Vanek's tumor: a case report

    PubMed Central

    Neishaboori, Hassan; Emadian, Omid

    2013-01-01

    Inflammatory fibroid polyp (known also as Vanek's tumor) is a type of localized, non-neoplastic inflammatory pseudotumor or inflammatory myofibroblastic tumor that occurs most commonly in the stomach but also in the small and large bowel. It is a documented cause of intussusception in adults. We report a case of a 40-year-old woman who presented with severe, postprandial abdominal pain followed by projectile vomiting over a period of three days. Ultrasonography demonstrated a solid and echogenic mass surrounded by the typical mural layers of an invaginated jejunum. She underwent urgent laparotomy and resection of an 18 cm tumor from the distal jejunum. The immuno-histopathological diagnosis after segmental jejunal resection was a jejunal inflammatory fibroid polyp. Although inflammatory fibroid polyps are seen very rarely in adults, they are among the probable diagnoses that should be considered in obstructive tumors of the small bowel causing intussusceptions. PMID:24834274

  4. Late-onset dysphagia caused by severe spastic peristalsis of a free jejunal graft in a case of hypopharyngeal cancer.

    PubMed

    Imai, Takayuki; Goto, Takahiro; Matsumoto, Ko; Kurosawa, Koreyuki; Asada, Yukinori; Saijo, Shigeru; Matsuura, Kazuto

    2016-12-01

    Free jejunal transfer is the main technique used for reconstructing a circumferential defect caused by total pharyngo-laryngo-cervical-esophagectomy in certain cancer cases. We report a rare case of severe late-onset dysphagia caused by autonomous spastic peristalsis, which led to complete obstruction of the free jejunal route. A 70-year-old man underwent treatment for hypopharyngeal cancer involving total pharyngolaryngectomy with free jejunal transfer. After uneventful peri- and postoperative recovery, he developed sudden-onset severe dysphagia 22 months later. Gastrografin fluoroscopy revealed abnormal peristalsis and contraction of the transferred jejunum, leading to complete obstruction. Nutritional treatment, application of depressants of peristalsis, and xylocaine injection into the outer space of the jejunal mucosa all failed to alleviate the dysphagia. Surgical treatment involving a longitudinal incision of the jejunal graft, and interposing a cutaneous flap, as a fixed wall, between the incised jejunal margins to prevent obstruction was performed. After further reconstructive surgery involving using a pectoralis major musculocutaneous flap and a split-thickness skin graft to close a refractory jejunum-skin fistula, the dysphagia was permanently alleviated. To our knowledge, this is the first report of severe dysphagia caused by peristalsis of a free jejunal graft.

  5. Late-onset dysphagia caused by severe spastic peristalsis of a free jejunal graft in a case of hypopharyngeal cancer.

    PubMed

    Imai, Takayuki; Goto, Takahiro; Matsumoto, Ko; Kurosawa, Koreyuki; Asada, Yukinori; Saijo, Shigeru; Matsuura, Kazuto

    2016-12-01

    Free jejunal transfer is the main technique used for reconstructing a circumferential defect caused by total pharyngo-laryngo-cervical-esophagectomy in certain cancer cases. We report a rare case of severe late-onset dysphagia caused by autonomous spastic peristalsis, which led to complete obstruction of the free jejunal route. A 70-year-old man underwent treatment for hypopharyngeal cancer involving total pharyngolaryngectomy with free jejunal transfer. After uneventful peri- and postoperative recovery, he developed sudden-onset severe dysphagia 22 months later. Gastrografin fluoroscopy revealed abnormal peristalsis and contraction of the transferred jejunum, leading to complete obstruction. Nutritional treatment, application of depressants of peristalsis, and xylocaine injection into the outer space of the jejunal mucosa all failed to alleviate the dysphagia. Surgical treatment involving a longitudinal incision of the jejunal graft, and interposing a cutaneous flap, as a fixed wall, between the incised jejunal margins to prevent obstruction was performed. After further reconstructive surgery involving using a pectoralis major musculocutaneous flap and a split-thickness skin graft to close a refractory jejunum-skin fistula, the dysphagia was permanently alleviated. To our knowledge, this is the first report of severe dysphagia caused by peristalsis of a free jejunal graft. PMID:27068782

  6. Peritonitis caused by jejunal perforation with Taenia saginata: report of a case.

    PubMed

    Bekraki, Ali; Hanna, Khalil

    2016-03-01

    Complicated Taeniasis necessitating surgical intervention is extremely rare and is usually reported to occur in the distal ileal region of the Gastrointestinal tract. A case of peritonitis secondary to proximal jejunal perforation due to Taenia saginata is presented. Preoperative evaluation suggested the diagnosis of acute duodenal ulcer perforation. Although no real change in management and outcome is present, Taenia remains an exceptional direct cause of intestinal perforation, and should be kept on the list of differential diagnosis of peritonitis and acute abdomen in endemic geographical locations. PMID:27065626

  7. Jejunal lymphangioma: an unusual cause of intussusception in an adult patient.

    PubMed

    Limaiem, F; Khalfallah, T; Marsaoui, L; Bouraoui, S; Lahmar, A; Mzabi, S

    2015-03-01

    Adult intussusception is a relatively rare clinical entity. Almost 90% of cases of intussusception in adults are secondary to a pathologic condition that serves as a lead point. Lymphangioma of the small bowel is an unusual tumour that has been rarely reported to cause intussusception. In this paper, we present a rare case of adult intussusception due to jejunal lymphangioma. A 22-year-old female patient with a medical history significant for anaemia presented with intermittent colicky abdominal pain, diarrhoea and oedema of the inferior limbs for the past three months. Ultrasonography and CT scan revealed a typical target sign with dilated intestinal loops. At laparotomy, a jejuno-jejunal intussusception was found. Partial resection of the jejunum was performed. Macroscopic examination of the surgical specimen revealed a pedunculated polyp measuring 2 cm in diameter. Histological sections of the polyp revealed in the lamina propria and submucosal layer of the jejunum several markedly dilated thin-walled lymphatic spaces lined with single layers of flat endothelial cells. The final pathologic diagnosis was submucosal lymphangioma. This case report indicates that intussusception, although rare in adults, should be considered in the differential diagnosis of abdominal pain. Moreover, it should be taken into consideration that lymphangioma is one of the possible lesions that can cause intussusception.

  8. Toxoplasma gondii causes death and plastic alteration in the jejunal myenteric plexus

    PubMed Central

    Araújo, Eduardo José de Almeida; Zaniolo, Larissa Marchi; Vicentino, Suellen Laís; Góis, Marcelo Biondaro; Zanoni, Jacqueline Nelisis; da Silva, Aristeu Vieira; Sant’Ana, Débora de Mello Gonçales

    2015-01-01

    AIM: To assess the effects of ME-49 Toxoplasma gondii (T. gondii) strain infection on the myenteric plexus and external muscle of the jejunum in rats. METHODS: Thirty rats were distributed into two groups: the control group (CG) (n = 15) received 1 mL of saline solution orally, and the infected group (IG) (n = 15) inoculated with 1 mL of saline solution containing 500 oocysts of M-49 T. gondii strain orally. After 36 d of infection, the rats were euthanized. Infection with T. gondii was confirmed by blood samples collected from all rats at the beginning and end of the experiment. The jejunum of five animals was removed and submitted to routine histological processing (paraffin) for analysis of external muscle thickness. The remaining jejunum from the others animals was used to analyze the general population and the NADH-diaphorase, VIPergic and nitrergic subpopulations of myenteric neurons; and the enteric glial cells (S100-IR). RESULTS: Serological analysis showed that animals from the IG were infected with the parasite. Hypertrophy affecting jejunal muscle thickness was observed in the IG rats (77.02 ± 42.71) in relation to the CG (51.40 ± 12.34), P < 0.05. In addition, 31.2% of the total number of myenteric neurons died (CG: 39839.3 ± 5362.3; IG: 26766.6 ± 2177.6; P < 0.05); hyperplasia of nitrergic myenteric neurons was observed (CG: 7959.0 ± 1290.4; IG: 10893.0 ± 1156.3; P < 0.05); general hypertrophy of the cell body in the remaining myenteric neurons was noted [CG: 232.5 (187.2-286.0); IG: 248.2 (204.4-293.0); P < 0.05]; hypertrophy of the smallest varicosities containing VIP neurotransmitter was seen (CG: 0.46 ± 0.10; IG: 0.80 ± 0.16; P < 0.05) and a reduction of 25.3% in enteric glia cells (CG: 12.64 ± 1.27; IG: 10.09 ± 2.10; P < 0.05) was observed in the infected rats. CONCLUSION: It was concluded that infection with oocysts of ME-49 T. gondii strain caused quantitative and plastic alterations in the myenteric plexus of the jejunum in rats. PMID

  9. Uterine rotation: a cause of intestinal obstruction.

    PubMed

    González-Mesa, Ernesto; Narbona, Isidoro; Cohen, Isaac; Villegas, Emilia; Cuenca, Celia

    2013-01-01

    Intestinal obstruction is an uncommon surgical emergency during pregnancy that affects seriously the prognosis of gestation. The underlying cause can be identified in the majority of cases and usually consists of adhesions secondary to previous abdominal or pelvic surgery, followed in order of frequency by intestinal volvuli. In recent years there have been no reports in which the gravid uterus has been the cause of intestinal obstruction. We report the case of a woman in week 33 + 4 of pregnancy who developed extrinsic compression of the colon secondary to uterine rotation and pelvic impaction of the head of the fetus.

  10. Rare Jejunal Diverticular Bleeding

    PubMed Central

    Christman, Emily; Hassell, Lewis A.; Kastens, Donald

    2016-01-01

    Severe gastrointestinal bleeding (GIB) secondary to jejunal diverticulosis (JD) is very rare. Delay in establishing a diagnosis is common and GIB from JD is associated with significant morbidity and mortality. We report an illustrative case diagnosed by push enteroscopy and managed with surgery. PMID:27800518

  11. Rotator Cuff Damage: Reexamining the Causes and Treatments.

    ERIC Educational Resources Information Center

    Nash, Heyward L.

    1988-01-01

    Sports medicine specialists are beginning to reexamine the causes and treatments of rotator cuff problems, questioning the role of primary impingement in a deficient or torn cuff and trying new surgical procedures as alternatives to the traditional open acromioplasty. (Author/CB)

  12. Uncomplicated jejunal diverticulosis with pneumoperitoneum

    PubMed Central

    Kwak, Jae Young; Park, Eun Hwa; Park, Cheon Soo; Kim, Ji Hoon; Han, Myeong Sik

    2016-01-01

    Small bowel diverticulosis is a rare finding within all bowel diverticuloses and jejunal diverticulosis is even rarer. Their relative clinical rarity and varied presentation may make diagnosis both delayed and difficult. We experienced a case of jejunal diverticulosis, which was diagnosed intraoperatively. A 55-year-old woman was admitted to Emergency Department with pneumoperitoneum on plain chest and abdominal film from a local clinic. She was hemodynamically stable with minimal tenderness on the left upper quadrant of the abdomen but no rebound tenderness. At surgery, small bowel torsion and jejunal diverticulosis were confirmed. Over 30 variable sized small bowel diverticula were noted on the mesenteric side of the proximal jejunum. The affected segment of the jejunum was about 180 cm. On exploration, we could not find any perforation site. No postoperative complications were observed, and the patient made a full recovery. Jejunal diverticulosis is rare, but it should not be regarded as insignificant. PMID:27274511

  13. A Rare Case of Jejunal Atresia Due to Intrauterine Intussusception.

    PubMed

    Joshi, Sanjeev B; Kinhal, Vidyadhar; Desai, Mahesh; Tilak; Choudhari, Fazal Ur Rehman

    2015-09-01

    Intestinal atresia is generally caused by intrauterine vascular obstructions involving mesenteric vessels. Intrauterine intussusceptions (IUI) are one of these disruptive events. Intestinal intussusceptions affects children commonly between 3 months and 3 years of age, but it rarely affects in intrauterine life. The relationship between intrauterine intussusception and intestinal atresia has been demonstrated by few cases in literature, suggesting intrauterine intussusception as a rare cause of intestinal atresia. We report a 7-day-old full term neonate presenting with intrauterine intussusceptions (jejuno-jejunal) resulting in jejunal atresia. PMID:26500958

  14. Differential Rotation and Angular Momentum Transport Caused by Thermal Convection in a Rotating Spherical Shell

    NASA Astrophysics Data System (ADS)

    Takehiro, S.; Sasaki, Y.; Hayashi, Y.-Y.; Yamada, M.

    2013-12-01

    We investigate generation mechanisms of differential rotation and angular momentum transport caused by Boussinesq thermal convection in a rotating spherical shell based on weakly nonlinear numerical calculations for various values of the Prandtl and Ekman numbers under a setup similar to the solar convection layer. When the Prandtl number is of order unity or less and the rotation rate of the system is small (the Ekman number is larger than O(10-2)), the structure of thermal convection is not governed by the Taylor-Proudman theorem; banana-type convection cells emerge which follow the spherical shell boundaries rather than the rotation axis. Due to the Coriolis effect, the velocity field associated with those types of convection cells accompanies the Reynolds stress which transports angular momentum from high-latitudes to the equatorial region horizontally, and equatorial prograde flows are produced. The surface and internal distributions of differential rotation realized in this regime are quite similar to those observed in the Sun with helioseismology. These results may suggest that we should apply larger values of the eddy diffusivities than those believed so far when we use a low resolution numerical model for thermal convection in the solar interior.

  15. Period Tripling Causes Rotating Spirals in Agitated Wet Granular Layers

    NASA Astrophysics Data System (ADS)

    Huang, Kai; Rehberg, Ingo

    2011-07-01

    Pattern formation of a thin layer of vertically agitated wet granular matter is investigated experimentally. Rotating spirals with three arms, which correspond to the kinks between regions with different colliding phases, are the dominating pattern. This preferred number of arms corresponds to period tripling of the agitated granular layer, unlike predominantly subharmonic Faraday crispations in dry granular matter. The chirality of the spatiotemporal pattern corresponds to the rotation direction of the spirals.

  16. Spontaneous Intra-Abdominal Hemorrhage Due to Rupture of Jejunal Artery Aneurysm in Behcet Disease

    PubMed Central

    Wu, Xiao-yan; Wei, Jiang-peng; Zhao, Xiu-yuan; Wang, Yue; Wu, Huan-huan; Shi, Tao; Liu, Tong; Liu, Gang

    2015-01-01

    Abstract Rupture of jejunal artery aneurysm is a very rare event resulting in life-threatening hemorrhage in Behcet disease (BD). We report a case of ruptured jejunal artery aneurysm in a 35-year-old patient with BD. The patient had a 1-year history of intermittent abdominal pain caused by superior mesenteric artery aneurysm with thrombosis. Anticoagulation treatment showed a good response. Past surgical history included stenting for aortic pseudoaneurysm. On admission, the patient underwent an urgent operation due to sudden hemorrhagic shock. Resection was performed for jejunal artery aneurysm and partial ischemia of intestine. The patient was diagnosed with BD, based on a history of recurrent oral and skin lesions over the past 6 years. Treatment with anti-inflammatory medications showed a good response during the 8-month follow-up. An increased awareness of BD and its vascular complications is essential. Aneurysms in BD involving jejunal artery are rare, neglected and require proper management to prevent rupture and death. To our knowledge, this is the first reported case of jejunal artery aneurysm caused by BD. PMID:26559278

  17. A Rotating Stall Type Phenomenon Caused by Cavitation in LE-7A LH2 Turbopump

    NASA Astrophysics Data System (ADS)

    Shimura, Takashi; Yoshida, Makoto; Kamijo, Kenjiro; Uchiumi, Masaharu; Yasutomi, Yoshinobu

    The cause of 350 Hz large-amplitude rotor vibration of the H-2A rocket's LE-7A fuel turbopump was investigated by wideband oscillating-pressure measurement. Measurement was successfully conducted by quartz-type pressure sensors in full-load liquid-hydrogen tests. The phase difference of pressure oscillations between two pressure measurement ports under conditions of pump cavitating operation revealed a phenomenon similar to rotating stall in turbomachinery which had not been previously observed. The rotating speed of a cell was 350 Hz, about a half the rotor speed. This phenomenon is different from rotating cavitation in which the cavitation pattern rotates around the periphery of an impeller faster than shaft rotating speed. Based on these findings, it was concluded that this phenomenon cased the large-amplitude 350 Hz vibration of the LE-7A fuel turbopump. Results of FFT analysis of measured oscillating pressure are presented.

  18. Anthropogenic versus Seismogenic Causes of the Rotation of a Lycian Sarcophagus in Pinara, SW-Turkey

    NASA Astrophysics Data System (ADS)

    Hinzen, Klaus-G.; Schreiber, Stephan; Yerli, Baris

    2010-05-01

    A Lycian sarcophagus located in the ancient city of Pınara, southwest Turkey, shows a clockwise rotation of 5.37° with respect to its North-South oriented foundation. The city of Pınara was occupied from the Lycian period, through Roman times to the Byzantine era. Considering the seismotectonic potential of the area and numerous other indications of earthquake related damages in the archaeological site, this rotation has also been attributed to earthquake ground motion before. We present a 3D model of the sarcophagus constructed out of 12 million points from a 3D laser scan. The sarcophagus has a foundation block directly worked out of the outcropping rock. On top of this is a 2.46 x 1.67 m and 0.91 m high base block on which the 1.64 m high coffin and lid of the same height are resting. The sarcophagus shows a crater in the eastern side of the coffin, which was most probably caused by the detonation of an explosive charge during a looting attempt. The direction of the rotation agrees with the sense expected from the blast. Therefore the question arises whether the rotation has a natural, seismogenic, or an anthropogenic cause. A rigid block model of the sarcophagus with a total weight of 26.5 t was derived from the laser scan with application of CAD. With the rigid block model we studied the feasibility of two alternative sources as the cause for the rotation of the coffin: an explosion and earthquake ground motion. Scaled recorded ground motions from local earthquakes and a strong motion record from the recent L'Aquila, Italy, earthquake were used to study the sarcophagus dynamic reactions to earthquake motions. The geometry of the structure requires large ground motion amplitudes to initiate rocking. However, rocking is necessary to produce rotation around the vertical axis by translational movements. The size of the explosion is back calculated from the crater size and compared to the duration and amplitude of an impulse necessary to rotate the coffin. All

  19. Recurrent Midgut Bleeding due to Jejunal Angioleiomyoma

    PubMed Central

    Mityushin, Petr

    2016-01-01

    Angioleiomyoma being a type of true smooth muscle gastrointestinal tumors can lead to serious life-threatening gastrointestinal bleeding. We report a case of 21-year-old male patient with recurrent midgut bleeding. Contrast-enhanced CT revealed highly vascular small bowel neoplasm. The patient underwent laparotomy with bowel resection and recovered uneventfully. Histopathology revealed jejunal angioleiomyoma. PMID:27668116

  20. Recurrent Midgut Bleeding due to Jejunal Angioleiomyoma.

    PubMed

    Gachabayov, Mahir; Mityushin, Petr

    2016-01-01

    Angioleiomyoma being a type of true smooth muscle gastrointestinal tumors can lead to serious life-threatening gastrointestinal bleeding. We report a case of 21-year-old male patient with recurrent midgut bleeding. Contrast-enhanced CT revealed highly vascular small bowel neoplasm. The patient underwent laparotomy with bowel resection and recovered uneventfully. Histopathology revealed jejunal angioleiomyoma. PMID:27668116

  1. Recurrent Midgut Bleeding due to Jejunal Angioleiomyoma

    PubMed Central

    Mityushin, Petr

    2016-01-01

    Angioleiomyoma being a type of true smooth muscle gastrointestinal tumors can lead to serious life-threatening gastrointestinal bleeding. We report a case of 21-year-old male patient with recurrent midgut bleeding. Contrast-enhanced CT revealed highly vascular small bowel neoplasm. The patient underwent laparotomy with bowel resection and recovered uneventfully. Histopathology revealed jejunal angioleiomyoma.

  2. Rotation change in the orientation of the centre-of-figure frame caused by large earthquakes

    NASA Astrophysics Data System (ADS)

    Zhou, Jiangcun; Sun, Wenke; Jin, Shuanggen; Sun, Heping; Xu, Jianqiao

    2016-08-01

    A method to estimate the rotation change in the orientation of the centre-of-figure (CF) frame caused by earthquakes is proposed for the first time. This method involves using the point dislocation theory based on a spherical, non-rotating, perfectly elastic and isotropic (SNREI) Earth. The rotation change in the orientation is related solely to the toroidal displacements of degree one induced by the vertical dip slip dislocation, and the spheroidal displacements induced by an earthquake have no contribution. The effects of two recent large earthquakes, the 2004 Sumatra and the 2011 Tohoku-Oki, are studied. Results showed that the Sumatra and Tohoku-Oki earthquakes both caused the CF frame to rotate by at least tens of μas (micro-arc-second). Although the visible co-seismic displacements are identified and removed from the coordinate time-series, the rotation change due to the unidentified ones and errors in removal is non-negligible. Therefore, the rotation change in the orientation of the CF frame due to seismic deformation should be taken into account in the future in reference frame and geodesy applications.

  3. Rotating wave packet caused by the superposition of two Bessel-Gauss beams

    NASA Astrophysics Data System (ADS)

    Zheng, Shuiqin; Cai, Yi; Li, Ying; Li, Jingzhen; Zheng, Guoliang; Chen, Hongyi; Xu, Shixiang

    2015-12-01

    This paper presents, theoretically, a rotating wave packet by overlapping two Bessel-Gauss beams with different longitudinal wave vectors and topological charges. Our results show that the angular velocity of this kind of packet varies with propagating distance, and that Gauss amplitude modulation thus depends strongly on the Fresnel number N f. In the far field, the angular velocity of the packet tends to zero, so the packet will no longer rotate. If N f > 3.18, the packet will rotate with a constant velocity or have a stable rotating velocity along the propagation distance. Interestingly, if appropriate Gauss waist size and propagating distance z are chosen so that 0.006 < N f < 3.18, both the amplitude and the direction of the rotating angular velocity can be manipulated for given topological charges and longitudinal wave vectors. The small Gauss waist radius can induce angular velocity dispersion, causing radial rotation with out-sync and thereby the phase distortion of the BG beam.

  4. Complicated jejunal diverticulosis: A case report with literature review

    PubMed Central

    Nejmeddine, Affes; Bassem, Abid; Mohamed, Hammami; Hazem, Ben ameur; Ramez, Beyrouti; Issam, Beyrouti Mohamed

    2009-01-01

    Context: Jejunal diverticuli are rare and usually asymptomatic. More commonly, they are seen as incidental findings on CT images, enteroclysis, or during surgery. Complications such as bleeding, perforation, obstruction, malabsorption, diverticulitis, blind loop syndrome, volvulus, and intussusceptions may warrant surgical intervention. Case report: We report a case of 47-year old woman who had suffered from intestinal obstruction for 3 days. The symptoms did not improve after conservative treatment. An exploratory laparotomy found small bowel obstruction due to proximal jejunal diverticulum with an adhesion epiploic band. Strangulation of the jejunum resulted from the internal hernia caused by the band. The band was removed and the proximal jejunum segmentally resected. The postoperative course was uneventful. Conclusion: Although this phenomenon is rare, we should keep in mind that intestinal diverticulosis may induce intestinal obstructions of different kinds, repeat physical examinations and X-ray films are needed and enteroclysis studies or CT scan are helpful in diagnosis. Surgery is indicated for acute abdominal or repeated intestinal obstruction. PMID:22666695

  5. Demanding response time requirements on coherent receivers due to fast polarization rotations caused by lightning events.

    PubMed

    Krummrich, Peter M; Ronnenberg, David; Schairer, Wolfgang; Wienold, Daniel; Jenau, Frank; Herrmann, Maximilian

    2016-05-30

    Lightning events can cause fast polarization rotations and phase changes in optical transmission fibers due to strong electrical currents and magnetic fields. Whereas these are unlikely to affect legacy transmission systems with direct detection, different mechanisms have to be considered in systems with local oscillator based coherent receivers and digital signal processing. A theoretical analysis reveals that lightning events can result in polarization rotations with speeds as fast as a few hundred kRad/s. We discuss possible mechanisms how such lightning events can affect coherent receivers with digital signal processing. In experimental investigations with a high current pulse generator and transponder prototypes, we observed post FEC errors after polarization rotation events which can be expected from lightning strikes. PMID:27410158

  6. Demanding response time requirements on coherent receivers due to fast polarization rotations caused by lightning events.

    PubMed

    Krummrich, Peter M; Ronnenberg, David; Schairer, Wolfgang; Wienold, Daniel; Jenau, Frank; Herrmann, Maximilian

    2016-05-30

    Lightning events can cause fast polarization rotations and phase changes in optical transmission fibers due to strong electrical currents and magnetic fields. Whereas these are unlikely to affect legacy transmission systems with direct detection, different mechanisms have to be considered in systems with local oscillator based coherent receivers and digital signal processing. A theoretical analysis reveals that lightning events can result in polarization rotations with speeds as fast as a few hundred kRad/s. We discuss possible mechanisms how such lightning events can affect coherent receivers with digital signal processing. In experimental investigations with a high current pulse generator and transponder prototypes, we observed post FEC errors after polarization rotation events which can be expected from lightning strikes.

  7. Crystal settling and crystal growth caused by Ostwald Ripening in a terrestrial magma ocean under rotation

    NASA Astrophysics Data System (ADS)

    Maas, C.; Moeller, A.; Hansen, U.

    2013-12-01

    About 4.5 billion years ago the earth was covered by a heavily convecting and rotating global magma ocean which was caused by an impact of a mars-sized impactor in a later stage of the earth's accretion. After the separation of metal and silicate (see A. Möller, U. Hansen (2013)) and the formation of the earth's core it began to crystallize. Small silicate crystals emerge and grow by Ostwald Ripening when the fluid is supersaturated. This process results in shrinking of small crystals and growing of large crystals on behalf of the smaller ones. This leads to an altering of the crystal settling time. One question which is still under great debate is whether fractional or equilibrium crystallization occurred in the magma ocean. Fractional crystallization means that different mineral fractions settle one after the other which would lead to a strongly differentiated mantle after solidification of the magma ocean. In contrast to that equilibrium crystallization would result in a well mixed mantle. Whether fractional or equilibrium crystallization occurred is for example important for the starting model of plate tectonics or the understanding of the mantle development until today. To study the change of crystal radius in a convecting and rotating magma ocean we employed a 3D numerical model. Due to the low viscosity and strong rotation the influence of rotation on the early magma Ocean cannot be neglected. In the model the crystals are able to influence each other and the fluid flow. They are able to grow, shrink, vanish and form and gravitational, Coriolis and drag forces due to the fluid act on them. In our present work we study the crystal settling depending on different rotation rates and rotation axes with two configurations. For the polar setting the rotation axis is parallel, at the equator it is perpendicular to gravity. Low rotation at the pole leads to a large fraction of suspended crystals. With increasing rotation the crystals settle and form a thick layer

  8. Jejunal tackle: a case report of complete jejunal transection in rugby union.

    PubMed

    Perry, William; Fischer, Jesse; Wakeman, Christopher

    2014-09-01

    Jejunal perforation as a result of blunt abdominal trauma during sport is particularly rare. We are aware of 6 reported cases of jejunal perforation in sport: 1 in hockey, 2 in football (soccer), and 3 in American football. This report presents the case of a 25-year-old professional rugby union player, who presented to an "After Hours" general practice clinic with increasing central abdominal and epigastric pain after a heavy tackle during an international match in New Zealand. Despite suffering complete jejunal transection, the patient continued to play on, only presenting to an After Hours general practice clinic 3 hours after the injury. The case demonstrates the remarkable physiological resilience of professional rugby players and acts as a reminder to maintain a high degree of suspicion for small bowel injury despite normal vital signs in healthy young patients with abdominal pain secondary to blunt trauma.

  9. Root cause determination of on-orbit degradation of the VIIRS rotating telescope assembly

    NASA Astrophysics Data System (ADS)

    Barrie, J. D.; Fuqua, P. D.; Meshishnek, M. J.; Ciofalo, M. R.; Chu, C. T.; Chaney, J. A.; Moision, R. M.; Graziani, L.

    2012-09-01

    The Visible Infrared Imaging Radiometer Suite (VIIRS) is a sensor onboard the recently launched Suomi NPP spacecraft. Shortly after launch, VIIRS was found to exhibit a pronounced decrease in the optical throughput of several bands, with the near-infrared bands being more affected than those in the visible. The anomaly investigation team performed several experiments that concluded the primary source of degradation was throughput loss in the VIIRS rotating telescope assembly, likely caused by ultraviolet light illumination. This paper will discuss the laboratory investigation that determined the root cause of the telescope degradation to be UV photo-darkening of a tungsten oxide contaminant film that had been inadvertently deposited during the mirror manufacturing process. We will present data from experiments conducted on witness mirrors manufactured along with the telescope, as well as other mirrors of the same type that were not contaminated.

  10. Rotation of the ionospheric electric potential caused by spatial gradients of ionospheric conductivity

    NASA Astrophysics Data System (ADS)

    Nakamizo, A.; Yoshikawa, A.; Ohtani, S.; Ieda, A.; Seki, K.

    2013-12-01

    The present study focuses on the relationship between the inhomogeneity of the ionospheric conductivity and the rotation of the ionospheric potential. By applying a simplified version of the Hall-conjugate separation method [Yoshikawa, in preparation] to a global ionospheric potential solver, we analyze calculated potential structures separating them into the primary field and secondary field (the polarization field generated by the Hall effect). Calculations are performed with the following conditions for simplification. Here we call the diagonal and off-diagonal components of the conductivity tensor used in the potential solver SGTT/SGPP and SGTP, respectively, and we regard them as Pedersen and Hall conductivities for the high-latitude region. Besides, we call SGTP 'effective-Hall conductivity' based on its characteristics. (1) The input is a dawn-dusk and day-night symmetric R1-FAC. (2) The basic conductivity distribution is homogeneous in the longitudinal direction with only the latitudinal gradient by solar EUV and equatorial enhancement, no day-night difference and no auroral enhancement. (3) From the basic distribution, SGTP is changed with respect to the fixed SGTT/SGPP with the Hall-Pedersen ratio and offset that are applied globally. It is confirmed that the rotation angle (polarization field) is not so changed when we add only offsets but it becomes larger as the Hall-Pedersen ratio increases. This result is not only consistent with a theoretical prediction [Yoshikawa et al., 2013b] but also provides the fact that the ionospheric internal process, the primary-secondary fields generation process, does affect largely on the potential structure, and eventually on the magnetosphere-ionosphere processes. By combining the previously obtained and current results, we will clarify how the potential structure is actually described by the primary field and secondary field. The results can be applied to qualitatively/quantitatively identify the ionospheric causes

  11. Characteristics of nobiletin-induced effects on jejunal contractility.

    PubMed

    Xiong, Yong-Jian; Chen, Da-Peng; Lv, Bo-Chao; Liu, Fang-Fei; Wang, Li; Lin, Yuan

    2014-04-01

    Nobiletin, a citrus polymethoxylated flavone, exhibits multiple biological properties including anti-inflammatory, anti-carcinogenic, and anti-insulin resistance effects. The present study found that nobiletin exerted significant stimulatory effects on the contractility of isolated rat jejunal segments in all 6 different low contractile states, and meanwhile significant inhibitory effects in all 6 different high contractile states, showing characteristics of bidirectional regulation (BR). Nobiletin-exerted BR on jejunal contractility was abolished in the presence of c-kit receptor tyrosine kinase inhibitor imatinib or Ca(2+) channel blocker verapamil. In the presence of neuroxin tetrodotoxin, nobiletin only exerted stimulatory effects on jejunal contractility in both low and high contractile states. Hemicholinium-3 and atropine partially blocked nobiletin-exerted stimulatory effects on jejunal contractility in low-Ca(2+)-induced low contractile state. Phentolamine or propranolol or l-NG-nitro-arginine significantly blocked nobiletin-exerted inhibitory effects on jejunal contractility in high-Ca(2+)-induced high contractile state respectively. The effects of nobiletin on myosin light chain kinase (MLCK) mRNA expression, MLCK protein content, and myosin light chain phosphorylation extent were also bidirectional. In summary, nobiletin-exerted BR depends on the contractile states of rat jejunal segments. Nobiletin-exerted BR requires the enteric nervous system, interstitial cell of Cajal, Ca(2+), and myosin phosphorylation-related mechanisms.

  12. On the experimental prediction of the stability threshold speed caused by rotating damping

    NASA Astrophysics Data System (ADS)

    Vervisch, B.; Derammelaere, S.; Stockman, K.; De Baets, P.; Loccufier, M.

    2016-08-01

    An ever increasing demand for lighter rotating machinery and higher operating speeds results in a raised probability of instabilities. Rotating damping is one of the reasons, instability occurs. Rotating damping, or rotor internal damping, is the damping related to all rotating parts while non-rotating damping appearing in the non-rotating parts. The present study describes a rotating setup, designed to investigate rotating damping experimentally. An efficient experimental procedure is presented to predict the stability threshold of a rotating machine. The setup consists of a long thin shaft with a disk in the middle and clamped boundary conditions. The goal is to extract the system poles as a function of the rotating speed. The real parts of these poles are used to construct the decay rate plot, which is an indication for the stability. The efficiency of the experimental procedure relies on the model chosen for the rotating shaft. It is shown that the shaft behavior can be approximated by a single degree of freedom model that incorporates a speed dependent damping. As such low measurement effort and only one randomly chosen measurement location are needed to construct the decay rate plot. As an excitation, an automated impact hammer is used and the response is measured by eddy current probes. The proposed method yields a reliable prediction of the stability threshold speed which is validated through measurements.

  13. Exposure to a Rotating Virtual Environment During Treadmill Locomotion Causes Adaptation in Heading Direction

    NASA Technical Reports Server (NTRS)

    Mulavara, A. P.; Richards, J. T.; Marshburn, A.; Nomura, Y.; Bloomberg, J. J.

    2005-01-01

    The goal of the present study was to investigate the adaptive effects of variation in the direction of optic flow, experienced during linear treadmill walking, on modifying locomotor trajectory. Subjects (n = 30) walked on a motorized linear treadmill at 4.0 km/h for 24 minutes while viewing the interior of a 3D virtual scene projected onto a screen 1.5 m in front of them. The virtual scene depicted constant self-motion equivalent to either 1) walking around the perimeter of a room to one s left (Rotating Room group) 2) walking down the center of a hallway (Infinite Hallway group). The scene was static for the first 4 minutes, and then constant rate self-motion was simulated for the remaining 20 minutes. Before and after the treadmill locomotion adaptation period, subjects performed five stepping trials where in each trial they marched in place to the beat of a metronome at 90 steps/min while blindfolded in a quiet room. The subject s final heading direction (deg), final X (for-aft, cm) and final Y (medio-lateral, cm) positions were measured for each trial. During the treadmill locomotion adaptation period subject s 3D torso position was measured. We found that subjects in the Rotating Room group as compared to the Infinite Hallway group: 1) showed significantly greater deviation during post exposure testing in the heading direction and Y position opposite to the direction of optic flow experienced during treadmill walking 2) showed a significant monotonically increasing torso yaw angular rotation bias in the direction of optic flow during the treadmill adaptation exposure period. Subjects in both groups showed greater forward translation (in the +X direction) during the post treadmill stepping task that differed significantly from their pre exposure performance. Subjects in both groups reported no perceptual deviation in position during the stepping tasks. We infer that 3 viewing simulated rotary self-motion during treadmill locomotion causes adaptive modification

  14. Exposure to a Rotating Virtual Environment During Treadmill Locomotion Causes Adaptation in Heading Direction

    NASA Technical Reports Server (NTRS)

    Ruttley, T; Marshburn, A.; Bloomberg, J. J.; Mulavara, A. P.; Richards, J. T.; Nomura, Y.

    2005-01-01

    The goal of the present study was to investigate the adaptive effects of variation in the direction of optic flow, experienced during linear treadmill walking, on modifying locomotor trajectory. Subjects (n = 30) walked on a motorized linear treadmill at 4.0 kilometers per hour for 24 minutes while viewing the interior of a 3D virtual scene projected onto a screen 1.5 in in front of them. The virtual scene depicted constant self-motion equivalent to either 1) walking around the perimeter of a room to one s left (Rotating Room group) 2) walking down the center of a hallway (Infinite Hallway group). The scene was static for the first 4 minutes, and then constant rate self-motion was simulated for the remaining 20 minutes. Before and after the treadmill locomotion adaptation period, subjects performed five stepping trials where in each trial they marched in place to the beat of a metronome at 90 steps/min while blindfolded in a quiet room. The subject's final heading direction (deg), final X (for-aft, cm) and final Y (medio-lateral, cm) positions were measured for each trial. During the treadmill locomotion adaptation period subject's 3D torso position was measured. We found that subjects in the Rotating Room group as compared to the Infinite Hallway group: 1) showed significantly greater deviation during post exposure testing in the heading direction and Y position opposite to the direction of optic flow experienced during treadmill walking 2) showed a significant monotonically increasing torso yaw angular rotation bias in the direction of optic flow during the treadmill adaptation exposure period. Subjects in both groups showed greater forward translation (in the +X direction) during the post treadmill stepping task that differed significantly from their pre exposure performance. Subjects in both groups reported no perceptual deviation in position during the stepping tasks. We infer that viewing simulated rotary self-motion during treadmill locomotion causes

  15. Upper G.I. hemorrhage from glass fragments’ ingestion in a patient with jejunal diverticula – Case report☆

    PubMed Central

    Gattai, Riccardo; Pantalone, Desire’; Migliaccio, Maria Luisa; Bonizzoli, Manuela; Peris, Adriano; Bechi, Paolo

    2014-01-01

    Introduction Acute upper gastrointestinal bleeding is a common emergency. The ingestion of foreign bodies represents a less frequent cause of bleeding, but it is equally life-threatening, especially if the patient does not report the incident. Presentation of case We are reporting the case of a 77-year-old patient with a bleeding caused by ingestion of glass fragments with co-existing jejunal diverticula. Discussion The ingestion of foreign bodies is a rare, mostly accidental event. Another possible source of upper G.I. bleeding is jejunal diverticula; in this case, the examination of the specimens showed evidence of glass ingestion fragments as the likely cause of bleeding. Conclusion Surgeons should be aware that patients may fail to report correctly on the possible causes of bleeding, misleading the diagnosis, and delaying the diagnostic routes. PMID:25543882

  16. Perforated jejunal diverticulum: a rare case of acute abdomen

    PubMed Central

    Sehgal, Rishabh; Cheung, Cherry X.; Hills, Tristram; Waris, Aqueel; Healy, Donagh; Khan, Tahir

    2016-01-01

    Jejunal pseudo-diverticulosis is a rare acquired herniation of the mucosa and submucosa through weakened areas of the muscularis mucosa of the mesenteric aspect of the bowel. They are asymptomatic in the majority of cases; however, they can present with a wide spectrum of non-specific symptoms such as chronic abdominal discomfort, postprandial flatulence, diarrhoea, malabsorption and steattorhoea. In up to 15% of cases, more serious acute complications may arise such as the development of intestinal obstruction, haemorrhage or as in our case, localized peritonitis secondary to perforation. Perforation carries an overall mortality rate of up to 40% and exploratory laparotomy followed by copious lavage with segmental resection and primary anastomosis remains the mainstay of managing such sequalae of jejunal pseudo-diverticulosis. Our case report highlights the importance of maintaining a high clinical suspicion of a perforated jejunal diverticulum in an elderly patient presenting with an acute abdomen. PMID:27765806

  17. Symbolic dynamics of jejunal motility in the irritable bowel

    NASA Astrophysics Data System (ADS)

    Wackerbauer, Renate; Schmidt, Thomas

    1999-09-01

    Different studies of the irritable bowel syndrome (IBS) by conventional analysis of jejunal motility report conflicting results. Therefore, our aim is to quantify the jejunal contraction activity by symbolic dynamics in order to discriminate between IBS and control subjects. Contraction amplitudes during fasting motility (phase II) are analyzed for 30 IBS and 30 healthy subjects. On the basis of a particular scale-independent discretization of the contraction amplitudes with respect to the median, IBS patients are characterized by increased block entropy as well as increased mean contraction amplitude. In a further more elementary level of analysis these differences can be reduced to specific contraction patterns within the time series, namely the fact that successive large contraction amplitudes are less ordered in IBS than in controls. These significant differences in jejunal motility may point to an altered control of the gut in IBS, although further studies on a representative number of patients have to be done for a validation of these findings.

  18. Jejunal intussusception and small bowel transmural infarction in a baboon (Papio hamadryas anubis).

    PubMed

    Cary, Max E; Suarez-Chavez, Maria; Wolf, Roman F; Kosanke, Stanley D; White, Gary L

    2006-03-01

    A 4.3-y-old, colony-bred female baboon (Papio hamadryas anubis) of low social rank and exhibiting no clinically significant signs of illness or distress was found dead at the Oklahoma University Health Sciences Center baboon breeding facility at El Reno, OK. Prior to death she exhibited excessive grooming behavior both toward herself and other baboons. In addition, she was consistently shy, timid, reclusive, and prone to minimal sustained movement (that is, generally lethargic behavior). Animals of low social rank typically exhibit some degree of these behaviors in order to avoid surplus interactions with other animals within their groups, which can lead to conflict and injury. Accordingly, her death was surprising in view of the apparent lack of clinical signs. Necropsy established the cause for death as systemic shock with resultant cardiovascular collapse resulting from a massive jejunal intussusception. This intussusception and resulting entrapment of the jejunal mesenteric vasculature caused total occlusion of the small bowel blood supply, with resulting hemorrhage and ischemic necrosis (small bowel infarction). Jejunal intussusceptions generally are considered to be uncommon and therefore are rarely reported in either the veterinary or human literature. Of special interest was the cause for this intussusception, determined to have been a large hairball located at the most proximal portion of the jejunum. Extending from this hairball and traversing essentially the entire length of the jejunum was a braided strand of hair acting as a string foreign body about which the intussusception formed. In light of our findings we suggest that animals of low social rank exhibiting excessive grooming behavior and lethargy might merit clinical evaluation to rule out possible abdominal disorders.

  19. Bacterial colonisation of jejunal mucosa in acute tropical sprue.

    PubMed

    Tomkins, A M; Drasar, B S; James, W P

    1975-01-11

    Fifteen of sixteen Caucasians with acute tropical sprue were founc to have numerous aerobic bacteria closely associated with the mucosal layer of the proximal jejunum. Four species of Enterobacteria were grown in eleven patients, and concentrations were higher in the mucosal patients than in the jejunal fluid. Only one of eight control cases with similar tropical exposure but without mucosal morphological abnormalities had any similar bacteria in the mucosal biopsy. In no case were Bacteroides isolated. Since clinical and biochemical improvement only occurred on treatment with tetracycline when enterobacteria were eliminated from the mucosa, it is suggested that these organisms may be responsible for persisting jejunal abnormalities in tropical sprue.

  20. Multiple indomethacin-induced jejunal ulcerations with perforation: a case report with histology.

    PubMed

    Risty, Gina M; Najarian, Melissa M; Shapiro, Stephen B

    2007-04-01

    Gastric and duodenal inflammation and ulceration are well-known complications of nonsteroidal anti-inflammatory (NSAID) usage. However, small bowel ulceration and perforation secondary to NSAID use is uncommon and has rarely been reported in the literature. We describe a perforated jejunal ulcer that developed in a patient using indomethacin for treatment of ankylosing spondylitis. We performed a literature review of NSAID-induced small bowel injury and compared the histology of NSAID-related injury with more familiar causes of small bowel perforation.

  1. Jejunal perforation due to porcupine quill ingestion in a horse.

    PubMed

    Anderson, Stacy L; Panizzi, Luca; Bracamonte, Jose

    2014-02-01

    An 8-month-old Andalusian filly was treated for jejunal perforations due to ingestion of a porcupine quill. During exploratory laparotomy, 2 separate stapled side-to-side jejunojejunal resection and anastomoses were performed. Post-operative complications after 2 years follow-up included mild incisional herniation following incisional infection and chronic intermittent colic.

  2. Jejunal perforation due to porcupine quill ingestion in a horse

    PubMed Central

    Anderson, Stacy L.; Panizzi, Luca; Bracamonte, Jose

    2014-01-01

    An 8-month-old Andalusian filly was treated for jejunal perforations due to ingestion of a porcupine quill. During exploratory laparotomy, 2 separate stapled side-to-side jejunojejunal resection and anastomoses were performed. Post-operative complications after 2 years follow-up included mild incisional herniation following incisional infection and chronic intermittent colic. PMID:24489394

  3. Jejunal perforation due to porcupine quill ingestion in a horse.

    PubMed

    Anderson, Stacy L; Panizzi, Luca; Bracamonte, Jose

    2014-02-01

    An 8-month-old Andalusian filly was treated for jejunal perforations due to ingestion of a porcupine quill. During exploratory laparotomy, 2 separate stapled side-to-side jejunojejunal resection and anastomoses were performed. Post-operative complications after 2 years follow-up included mild incisional herniation following incisional infection and chronic intermittent colic. PMID:24489394

  4. Evidence that Escherichia coli STb enterotoxin binds to lipidic components extracted from the pig jejunal mucosa.

    PubMed

    Rousset, E; Dubreuil, J D

    1999-11-01

    Escherichia coli strains producing the heat-stable enterotoxin STb cause diarrhoea in pigs, but little is known on the receptor binding step initiating the diarrhoeal process. In the present study, pig jejunal mucosa extracts were tested for the presence of binding component(s) for STb. Jejunal epithelial cells and the mucus layer were analyzed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The separated material was transferred to a polyvinylidene difluoride (PVDF) membrane and overlayed with STb. The results indicated that a band migrating with the tracking dye was bound by STb. This band was not stained by Coomassie blue and was thus regarded as non proteinic but rather as a lipidic component. Thus, total lipid extracts were obtained from the epithelial cells and the mucus layer. Compared to SDS-PAGE on 12% gels, a better separation of the low molecular mass components contained in these extracts was obtained using high-density Phastgel. Most of the components were detected following silver staining but not using Coomassie blue. Interestingly, commercially available pure glycolipids could also be visualized, after separation, only following silver staining. In the total lipid extracts, a band migrating in the 2.5-6.5 kDa range was observed. Using a monoclonal antisulfatide antibody, this band was recognized indicating that sulfatide was, in effect, present in the extract. When pure sulfatide was run on the same gels, it showed the same electrophoretic mobility. In addition, a dose dependent binding of STb to sulfatide could be observed. Taken together, these data suggested that sulfatide present on the jejunal mucosa, could represent a natural target binding molecule for STb. PMID:10482388

  5. Fast rotational motion of water molecules increases ordering of hydrophobes in solutions and may cause hydrophobic chains to collapse.

    PubMed

    Mohorič, Tomaž; Bren, Urban; Vlachy, Vojko

    2015-12-28

    Using the molecular dynamics simulations with separate thermostats for translational and rotational degrees of freedom, we investigate the effects of water's rotational motion on the interaction among Lennard-Jones solutes. The situation with rotational temperature higher than the translational one (TR > TT) is mimicking the effects of microwaves on model solutions. Molecular dynamics simulations suggest that solutions of Lennard-Jones solutes become increasingly more structured with the rise in TR, while keeping the TT constant. This is evidenced by an increase of the first and the second peak of the solute-solute radial distribution function. In addition, the first peak moves toward slightly larger distances; the effect seems to be caused by the destabilization of water molecules in the first hydration shell around hydrophobic solutes. More evidence of strong effects of the rotationally excited water is provided by the simulations of short hydrophobic polymers, which upon an increase in TR assume more compact conformations. In these simulations, we see the re-distribution of water molecules, which escape from hydrophobic "pockets" to better solvate the solvent exposed monomers.

  6. Fast rotational motion of water molecules increases ordering of hydrophobes in solutions and may cause hydrophobic chains to collapse

    NASA Astrophysics Data System (ADS)

    Mohorič, Tomaž; Bren, Urban; Vlachy, Vojko

    2015-12-01

    Using the molecular dynamics simulations with separate thermostats for translational and rotational degrees of freedom, we investigate the effects of water's rotational motion on the interaction among Lennard-Jones solutes. The situation with rotational temperature higher than the translational one (TR > TT) is mimicking the effects of microwaves on model solutions. Molecular dynamics simulations suggest that solutions of Lennard-Jones solutes become increasingly more structured with the rise in TR, while keeping the TT constant. This is evidenced by an increase of the first and the second peak of the solute-solute radial distribution function. In addition, the first peak moves toward slightly larger distances; the effect seems to be caused by the destabilization of water molecules in the first hydration shell around hydrophobic solutes. More evidence of strong effects of the rotationally excited water is provided by the simulations of short hydrophobic polymers, which upon an increase in TR assume more compact conformations. In these simulations, we see the re-distribution of water molecules, which escape from hydrophobic "pockets" to better solvate the solvent exposed monomers.

  7. An approach for online evaluations of dose consequences caused by small rotational setup errors in intracranial stereotactic radiation therapy

    SciTech Connect

    Lu Bo; Li, Jonathan; Kahler, Darren; Yan Guanghua; Mittauer, Kathryn; Shi Wenyin; Okunieff, Paul; Liu, Chihray

    2011-11-15

    Purpose: The purpose of this work is to investigate the impact of small rotational errors on the magnitudes and distributions of spatial dose variations for intracranial stereotactic radiotherapy (SRT) treatment setups, and to assess the feasibility of using the original dose map overlaid with rotated contours (ODMORC) method as a fast, online evaluation tool to estimate dose changes (using DVHs) to clinical target volumes (CTVs) and organs-at-risks (OARs) caused by small rotational setup errors. Methods: Fifteen intracranial SRT cases treated with either three-dimensional conformal radiation therapy (3DCRT) or intensity-modulated radiation therapy (IMRT) techniques were chosen for the study. Selected cases have a variety of anatomical dimensions and pathologies. Angles of {+-}3 deg. and {+-}5 deg. in all directions were selected to simulate the rotational errors. Dose variations in different regions of the brain, CTVs, and OARs were evaluated to illustrate the various spatial effects of dose differences before and after rotations. DVHs accounting for rotations that were recomputed by the treatment planning system (TPS) and those generated by the ODMORC method were compared. A framework of a fast algorithm for multicontour rotation implemented by ODMORC is introduced as well. Results: The average values of relative dose variations between original dose and recomputed dose accounting for rotations were greater than 4.0% and 10.0% in absolute mean and in standard deviation, respectively, at the skull and adjacent regions for all cases. They were less than 1.0% and 2.5% in absolute mean and in standard deviation, respectively, for dose points 3 mm away from the skull. The results indicated that spatial dose to any part of the brain organs or tumors separated from the skull or head surface would be relatively stable before and after rotations. Statistical data of CTVs and OARs indicate the lens and cochleas have the large dose variations before and after rotations

  8. Magnetic field variation caused by rotational speed change in a magnetohydrodynamic dynamo.

    PubMed

    Miyagoshi, Takehiro; Hamano, Yozo

    2013-09-20

    We have performed numerical magnetohydrodynamic dynamo simulations in a spherical shell with rotational speed or length-of-day (LOD) variation, which is motivated by correlations between geomagnetic field and climatic variations with ice and non-ice ages. The results show that LOD variation leads to magnetic field variation whose amplitude is considerably larger than that of LOD variation. The heat flux at the outer sphere and the zonal flow also change. The mechanism of the magnetic field variation due to LOD variation is also found. The keys are changes of dynamo activity and Joule heating.

  9. Rotational Spin-up Caused CO2 Outgassing on Comet 103P/Hartley 2

    NASA Astrophysics Data System (ADS)

    Steckloff, Jordan; Graves, Kevin; Hirabayashi, Masatoshi; Richardson, James

    2015-11-01

    The Deep Impact spacecraft’s flyby of comet 103P/Hartley 2 on November 4, 2010 revealed its nucleus to be a small, bilobate, and highly active world [1] [2]. The bulk of this activity is driven by CO2 sublimation, which is enigmatically restricted to the tip of the small lobe [1]. Because Hartley 2's CO2 production responds to the diurnal cycle of the nucleus [1], CO2 ice must be no deeper than a few centimeters below the surface of the small lobe. However the high volatility of CO2 would suggest that its sublimation front should recede deep below the surface, such that diurnal volatile production is dominated by more refractory species such as water ice, as was observed at comet Tempel 1 [3].Here we show that both the near surface CO2 ice and its geographic restriction to the tip of the small lobe suggest that Hartley 2 recently experienced an episode of fast rotation. We use the GRAVMAP code to compute the stability of slopes on the surface of Hartley 2 as a function of spin period. We determine that the surface of the active region of Hartley 2’s small lobe becomes unstable at a rotation period of ~10-12 hours (as opposed to its current spin period of ~ 18 hours [1]), and will flow toward the tip of the lobe, excavating buried CO2 ice and activating CO2-driven activity. However, the rest of the surface of the nucleus is stable at these spin rates, and will therefore not exhibit CO2 activity. We additionally use Finite Element Model (FEM) analysis to demonstrate that the interior of Hartley 2’s nucleus is structurally stable (assuming a cohesive strength of at least 5 Pa) at these spin rates.The uncommonly high angular acceleration of Hartley 2, which has changed the nucleus spin period by two hours in three months [4], suggests that this episode of fast rotation may have existed only a few years or decades ago. Thus, Hartley 2 may provide an excellent case study into the reactivation of quiescent comet nuclei via rotational spin up, as would result from

  10. Jejuno-jejunal intussusception: an unusual complication of feeding jejunostomy.

    PubMed

    Krishna, Sunil; Prabhu, Raghunath; Thangavelu, Siddharth; Shenoy, Rajgopal

    2013-01-01

    The jejuno-jejunal intussusception is a rare complication of jejunostomy tube placement. We are reporting a case of 33-year-old man who was suffering from absolute dysphagia due to carcinoma of cricopharynx with advanced metastatic disease, who underwent Stamms feeding jejunostomy as a part of palliative care. After 1 month he presented with colicky type of pain in the abdomen and vomiting. Sonogram of abdomen revealed a target sign and a feeding tube in a dilated jejunum. Abdominal CT proved the sonographic impression of jejuno-jejunal intussusception. He, therefore, underwent exploratory laparotomy and resection and anastomosis of the intussuscepted bowel. New feeding jejunostomy (FJ) was done distally from the anastomotic site. As per the literature this complication has been reported in Witzels jejunostomy. In our case the patient had undergone Stamms jejunostomy with placement of a Ryle's tube. Intussusception should be considered if a patient comes with abdominal pain and vomiting following FJ.

  11. Jejuno-jejunal intussusception: an unusual complication of feeding jejunostomy

    PubMed Central

    Krishna, Sunil; Prabhu, Raghunath; Thangavelu, Siddharth; Shenoy, Rajgopal

    2013-01-01

    The jejuno-jejunal intussusception is a rare complication of jejunostomy tube placement. We are reporting a case of 33-year-old man who was suffering from absolute dysphagia due to carcinoma of cricopharynx with advanced metastatic disease, who underwent Stamms feeding jejunostomy as a part of palliative care. After 1 month he presented with colicky type of pain in the abdomen and vomiting. Sonogram of abdomen revealed a target sign and a feeding tube in a dilated jejunum. Abdominal CT proved the sonographic impression of jejuno-jejunal intussusception. He, therefore, underwent exploratory laparotomy and resection and anastomosis of the intussuscepted bowel. New feeding jejunostomy (FJ) was done distally from the anastomotic site. As per the literature this complication has been reported in Witzels jejunostomy. In our case the patient had undergone Stamms jejunostomy with placement of a Ryle's tube. Intussusception should be considered if a patient comes with abdominal pain and vomiting following FJ. PMID:23814219

  12. An Atypical Presentation of Sporadic Jejunal Burkitt's Lymphoma.

    PubMed

    Naik, Pratik; Wang, James; Brazeau, Michael J; Rosario, Domingo

    2016-01-01

    Burkitt's lymphoma is a very aggressive type of B-cell NHL with replication approaching 100%. Primary gastrointestinal lymphoma is rare. In our case, a 24-year-old male initially presented with symptomatic anemia. He was initially evaluated with colonoscopy and EGD, both of which were unremarkable. A capsule endoscopy was then performed to further evaluate his significant anemia which revealed friable inflamed ulcerated mass in the jejunum. A push enteroscopy was then performed to obtain tissue from the jejunal mass. Biopsy results and immunohistochemical stains were consistent with Burkitt's lymphoma. PET/CT scan revealed only jejunal involvement. Treatment consisted of bowel resection prior to chemotherapy due to concern for perforation with chemotherapy. Patient achieved complete remission after the treatment. PMID:27672459

  13. An Atypical Presentation of Sporadic Jejunal Burkitt's Lymphoma

    PubMed Central

    2016-01-01

    Burkitt's lymphoma is a very aggressive type of B-cell NHL with replication approaching 100%. Primary gastrointestinal lymphoma is rare. In our case, a 24-year-old male initially presented with symptomatic anemia. He was initially evaluated with colonoscopy and EGD, both of which were unremarkable. A capsule endoscopy was then performed to further evaluate his significant anemia which revealed friable inflamed ulcerated mass in the jejunum. A push enteroscopy was then performed to obtain tissue from the jejunal mass. Biopsy results and immunohistochemical stains were consistent with Burkitt's lymphoma. PET/CT scan revealed only jejunal involvement. Treatment consisted of bowel resection prior to chemotherapy due to concern for perforation with chemotherapy. Patient achieved complete remission after the treatment.

  14. An Atypical Presentation of Sporadic Jejunal Burkitt's Lymphoma

    PubMed Central

    2016-01-01

    Burkitt's lymphoma is a very aggressive type of B-cell NHL with replication approaching 100%. Primary gastrointestinal lymphoma is rare. In our case, a 24-year-old male initially presented with symptomatic anemia. He was initially evaluated with colonoscopy and EGD, both of which were unremarkable. A capsule endoscopy was then performed to further evaluate his significant anemia which revealed friable inflamed ulcerated mass in the jejunum. A push enteroscopy was then performed to obtain tissue from the jejunal mass. Biopsy results and immunohistochemical stains were consistent with Burkitt's lymphoma. PET/CT scan revealed only jejunal involvement. Treatment consisted of bowel resection prior to chemotherapy due to concern for perforation with chemotherapy. Patient achieved complete remission after the treatment. PMID:27672459

  15. The clinical and metabolic significance of jejunal diverticula

    PubMed Central

    Cooke, W. T.; Cox, E. V.; Fone, D. J.; Meynell, M. J.; Gaddie, R.

    1963-01-01

    A study of 33 patients with jejunal diverticula showed that all except four had symptoms or metabolic upsets attributable to the presence of the diverticula. A disturbance of vitamin B12 metabolism or absorption was found in 16 patients and neuropathy was found in 12 patients. It is considered that abnormal bacterial activity in the small intestine is an important factor in these patients. PMID:14022799

  16. GASTRIC AND JEJUNAL HISTOPATHOLOGICAL CHANGES IN PATIENTS UNDERGOING BARIATRIC SURGERY

    PubMed Central

    RODRIGUES, Rosemary Simões Nomelini; ALMEIDA, Élia Cláudia de Souza; CAMILO, Silvia Maria Perrone; TERRA-JÚNIOR, Júverson Alves; GUIMARÃES, Lucinda Calheiros; DUQUE, Ana Cristina da Rocha; ETCHEBEHERE, Renata Margarida

    2016-01-01

    ABSTRACT Background: Morbid obesity is a multifactorial disease that increasingly is being treated by surgery. Aim: To evaluate gastric histopathological changes in obese, and to compare with patients who underwent gastrojejunal bypass and the jejunal mucosa after the surgery. Methods: This is an observational study performed at a tertiary public hospital, evaluating endoscopic biopsies from 36 preoperative patients and 35 postoperative. Results: In the preoperative group, 80.6% had chronic gastritis, which was active in 38.9% (77.1% and 20.1%, respectively, in the postoperative). The postoperative group had a significant reduction in H. pylori infection (p=0.0001). A longer length of the gastric stump and a time since surgery of more than two years were associated with Helicobacter pylori infection. The jejunal mucosa was normal in 91.4% and showed slight nonspecific chronic inflammation in 8.6%. Conclusion: There was a reduction in the incidence of Helicobacter pylori infection in the postoperative group. A longer length of the gastric stump and longer time elapsed since surgery were associated with Helicobacter pylori infection. The jejunal mucosa was considered normal in an absolute majority of patients. PMID:27683773

  17. Annoyance caused by advanced turboprop aircraft flyover noise: Counter-rotating-propeller configuration

    NASA Technical Reports Server (NTRS)

    Mccurdy, David A.

    1990-01-01

    Two experiments were conducted to quantify the annoyance of people to flyover noise of advanced turboprop aircraft with counter rotating propellers. The first experiment examined configurations having an equal number of blades on each rotor and the second experiment examined configurations having an unequal number of blades on each rotor. The objectives were to determine the effects on annoyance of various tonal characteristics, and to compare annoyance to advanced turboprops with annoyance to conventional turboprops and turbofans. A computer was used to synthesize realistic, time-varying simulations of advanced turboprop aircraft takeoff noise. The simulations represented different combinations fundamental frequency and tone-to-broadband noise ratio. Also included in each experiment were recordings of 10 conventional turboprop and turbofan takeoffs. Each noise was presented at three sound pressure levels in an anechoic chamber. In each experiment, 64 subjects judged the annoyance of each noise stimulus. Analyses indicated that annoyance was significantly affected by the interaction of fundamental frequency with tone-to-broadband noise ratio. No significant differences in annoyance between the advanced turboprop aircraft and the conventional turbofans were found. The use of a duration correction and a modified tone correction improved the annoyance prediction for the stimuli.

  18. Geomechanical simulation of the stress tensor rotation caused by injection of cold water in a deep geothermal reservoir

    NASA Astrophysics Data System (ADS)

    Jeanne, Pierre; Rutqvist, Jonny; Dobson, Patrick F.; Garcia, Julio; Walters, Mark; Hartline, Craig; Borgia, Andrea

    2015-12-01

    We present a three-dimensional thermohydromechanical numerical study of the evolution and distribution of the stress tensor within the northwest part of The Geysers geothermal reservoir (in California), including a detailed study of the region around one injection well from 2003 to 2012. Initially, after imposing a normal faulting stress regime, we calculated local changes in the stress regime around injection wells. Our results were compared with previously published studies in which the stress state was inferred from inverting the focal plane mechanism of seismic events. Our main finding is that changes in stress tensor orientation are caused by injection-induced progressive cooling of the reservoir, as well as by the seasonal variations in injection rate. Because of the gravity flow and cooling around a liquid zone formed by the injection, the vertical stress reduction is larger and propagates far below the injection well. At the same time, the horizontal stress increases, mostly because of stress redistribution below and above the cooling area. These two phenomena cause the rotation of the stress tensor and the appearance of a strike-slip regime above, inside, and below the cooling area. The cooling and the associated rotation of the stress regime can play a significant role in the observed long-term deepening of the microseismicity below active injection wells.

  19. The immediate response of jejunal mucosa to small bowel heterotopic allotransplatation in rats.

    PubMed

    Jonecová, Z; Tóth, Š; Varga, J; Staško, P; Kovalčinová, B; Maretta, M; Veselá, J

    2014-02-01

    The course of histopathological alterations within jejunal graft architecture during the initial adaptation phase in the host body was investigated. Graft tissues were compared to the intestinal tissues of the recipients. This study demonstrates: (1) renewal of intestinal epithelial lining in the graft biopsies during initial hours after transplantation is more likely caused by migration and extension of remaining epithelial cells than by their increased mitotic division. (2) Distinct decrease in histopathological injury was observed in transplanted grafts after 6h, but the morphometrical parameters, particularly villus height and wall thickness, remained altered. (3) Significant decrease in apoptotic cell death in the epithelial lining within 6h of graft recirculation was accompanied by no effect on apoptosis levels of the cells in lamina propria connective tissue. (4) Although the apoptosis level in the connective tissue cells was not modulated in the grafts within the first hour after transplantation, caspase-3 dependent apoptosis was decreased significantly. PMID:24079856

  20. Ileal impaction and jejunal enterotomy in a 4-month-old Arabian filly.

    PubMed

    Davis, Heather A; Munsterman, Amelia

    2012-01-01

    A 4-month-old Arabian filly was treated by surgical correction of an ileal impaction. The impaction was resolved through a distal jejunal enterotomy. One-year follow-up showed no post-operative complications secondary to the enterotomy. Jejunal enterotomy may be a surgical option for resolution of an ileal impaction.

  1. Ileal impaction and jejunal enterotomy in a 4-month-old Arabian filly.

    PubMed

    Davis, Heather A; Munsterman, Amelia

    2012-01-01

    A 4-month-old Arabian filly was treated by surgical correction of an ileal impaction. The impaction was resolved through a distal jejunal enterotomy. One-year follow-up showed no post-operative complications secondary to the enterotomy. Jejunal enterotomy may be a surgical option for resolution of an ileal impaction. PMID:22753967

  2. Filling in of Fraunhofer and gas-absorption lines in sky spectra as caused by rotational Raman scattering.

    PubMed

    Sioris, C E; Evans, W F

    1999-04-20

    A line-by-line radiative-transfer model to quantify the Ring effect as caused by rotational Raman scattering has been developed for the 310-550-nm spectral interval. The solar zenith angle and the resolution are key input parameters, as is the sky spectrum (excluding inelastic atmospheric scattering), which was modeled with MODTRAN 3.5. The filling in is modeled for ground-based viewing geometry and includes surface reflection and single inelastic scattering. It is shown that O2 contributes half of the filling in of N2. A strong inverse relationship with wavelength is noted in the filling in. A comparison with observations shows moderate agreement. The largest filling in occurs in the Ca II K and H lines.

  3. [The latest results of the advanced hypopharyngeal cancer surgery with immediate reconstruction using the free jejunal autograft].

    PubMed

    Jegliński, T; Szmidt, J; Szlenk, Z; Frunze, S

    1994-01-01

    In 21 patients with T3, T4 pharyngo-laryngeal cancer circumferential resection with immediate reconstruction using a free revascularized jejunal autograft was performed. In 13 cases the jejunal reconstruction was successful. In patients previously not irradiated the rate of success was 75% and in irradiated ones 37.5%. Five patients survived more than 5 years: one more than 7, two more than 6 and one more than 5. One patient with an unsuccessful jejunal graft and with subsequent skin reconstruction survived more than 6 years. The causes of failure were:-irreversible spasm of the arteries in 2 cases, skinking of the vessels resulting in flap necrosis in flap necrosis in 2 cases, -necrosis due to widespread atherosclerosis of the cervical arteries in 3 cases and of an unknown cause in 1 case. The cause of death was: widespread metastases in 12 cases, C.V.A. in 1 case, road traffic accident in 1 case, complications of the ileus in 1 case and carotid artery haemorrhage in 1 case. One of the successful patients was irradiated postoperatively, because the pathology report stated there was incomplete resection, and survived more than 6 years with no disturbance of swallowing. In general 10 patients died in the first year, 4 in the second, 1 in the third and 1 in the fourth--without any signs of recurrence. The five year survival of 24% in the presented group is relatively high in comparison with the generally accessible data for T3, T4 hypopharyngeal carcinoma treated by any of the usual methods. PMID:7970759

  4. Jejunal microflora in malnourished Gambian children.

    PubMed Central

    Heyworth, B; Brown, J

    1975-01-01

    Growth of bacteria greater than 10-5 organisms/ml was found in 22 children, of whom 17 gave a histroy of chronic diarrhoea. The other 8 children had either no diarrhoea or where having an acute attack lasting for a few days. In those with chronic diarrhoea, Esch. coli, bacteroides, and enterococci tended to occur more frequently, whereas streptococci occurred more frequently in those with acute diarrhoea. Bacilli, staphylococci, micrococci, klebsiellas, pseudomonads, and candidas often occurred in both groups and in large numbers in those with chronic diarrhoea. This confirms previous reports in other parts of the world that some children with malnutrition have considerable bacterial contamination of the jejunum, and that this may be of aetiological significance as a cause of much of the diarrhoea seen in malnourished children. It is possible too that this may be important in the pathogenesis of malnutrition. The presence of intestinal parasites in these malnourished children is also noted. A double-blind trial in the use of antibiotics in this condition is advocated to determine whether it is possible to break the diarrhoea-malabsorption-malnutrition cycle. At the same time the effect of simply removing the child to a more sanitary environment, together with an estimate of the natural clearance of bacteria from the upper intestine, should be evaluated. PMID:1092272

  5. Effects of spaceflight on the proliferation of jejunal mucosal cells

    NASA Technical Reports Server (NTRS)

    Phillips, Robert W.; Moeller, C. L.; Sawyer, Heywood R.; Smirnov, K. L.

    1991-01-01

    The purpose of this project was to test the hypothesis that the generalized, whole body decrease in synthetic activity due to microgravity conditions encountered during spaceflight would be demonstrable in cells and tissues characterized by a rapid rate of turnover. Jejunal mucosal cells were chosen as a model since these cells are among the most rapidly proliferating in the body. Accordingly, the percentage of mitotic cells present in the crypts of Lieberkuhn in each of 5 rats flown on the COSMOS 2044 mission were compared to the percentage of mitotic cells present in the crypts in rats included in each of 3 ground control groups (i.e., vivarium, synchronous and caudal-elevated). No significant difference (p greater than .05) was detected in mitotic indices between the flight and vivarium group. Although the ability of jejunal mucosal cells to divide by mitosis was not impaired in flight group, there was, however, a reduction in the length of villi and depth of crypts. The concommitant reduction in villus length and crypth depth in the flight group probably reflects changes in connective tissue components within the core of villi.

  6. Properties of Adenyl Cyclase from Human Jejunal Mucosa during Naturally Acquired Cholera and Convalescence

    PubMed Central

    Chen, Lincoln C.; Rohde, Jon E.; Sharp, Geoffrey W. G.

    1972-01-01

    The enterotoxin of Vibrio cholerae causes copious fluid production throughout the lenght of the small intestine. As this is thought to be mediated by stimulation of adenyl cyclase, a study has been made of the activity and properties of this enzyme in jejunal biopsy tissue taken from patients during the diarrheal phase of cholera and after recovery. Adenyl cyclase activity during cholera was increased more than twofold relative to the enzyme in convalescence. Under both conditions stimulation by prostaglandin E1 (PGE1) and by fluoride was observed. The responsiveness to PGE1 was not altered in cholera; the total activity of the fluoride-stimulated enzyme was similar, a finding that suggests cholera toxin stimulates pre-existing enzyme in the intestinal cell. The enzymes during cholera and convalescence were similar in all other properties examined. Optimal Mg++ concentration was 10 mM; Mn++ at 5 mM stimulated the enzyme but could not replace Mg++ except in the presence of 10 mM fluoride. Calcium was markedly inhibitory at concentrations greater than 10-4 M. The pH optimum was 7.5 and the Michaelis constant (Km) for ATP concentration approximated 10-4 M. Thus the interaction of cholera toxin with human intestinal adenyl cyclase does not alter the basic properties of the enzyme. When biopsy specimens were maintained intact in oxygenated Ringer's solution at 0°C, no loss of activity was observed at 1½ and 3 hr. In contrast, when the cells were homogenized, rapid loss of activity, with a half-life of 90 min was seen even at 0°C. Consequently for comparative assays of human jejunal adenyl cyclase, strict control of the experimental conditions is required. It was under such conditions that a twofold increase in basal adenyl cyclase activity during cholera was observed. Images PMID:4335441

  7. Improved Cell Line IPEC-J2, Characterized as a Model for Porcine Jejunal Epithelium

    PubMed Central

    Zakrzewski, Silke S.; Richter, Jan F.; Krug, Susanne M.; Jebautzke, Britta; Lee, In-Fah M.; Rieger, Juliane; Sachtleben, Monika; Bondzio, Angelika; Schulzke, Jörg D.; Fromm, Michael; Günzel, Dorothee

    2013-01-01

    Cell lines matching the source epithelium are indispensable for investigating porcine intestinal transport and barrier properties on a subcellular or molecular level and furthermore help to reduce animal usage. The porcine jejunal cell line IPEC-J2 is established as an in vitro model for porcine infection studies but exhibits atypically high transepithelial resistances (TER) and only low active transport rates so that the effect of nutritional factors cannot be reliably investigated. This study aimed to properly remodel IPEC-J2 and then to re-characterize these cells regarding epithelial architecture, expression of barrier-relevant tight junction (TJ) proteins, adequate TER and transport function, and reaction to secretagogues. For this, IPEC-J2 monolayers were cultured on permeable supports, either under conventional (fetal bovine serum, FBS) or species-specific (porcine serum, PS) conditions. Porcine jejunal mucosa was analyzed for comparison. Main results were that under PS conditions (IPEC-J2/PS), compared to conventional FBS culture (IPEC-J2/FBS), the cell height increased 6-fold while the cell diameter was reduced by 50%. The apical cell membrane of IPEC-J2/PS exhibited typical microvilli. Most importantly, PS caused a one order of magnitude reduction of TER and of trans- and paracellular resistance, and a 2-fold increase in secretory response to forskolin when compared to FBS condition. TJ ultrastructure and appearance of TJ proteins changed dramatically in IPEC-J2/PS. Most parameters measured under PS conditions were much closer to those of typical pig jejunocytes than ever reported since the cell line’s initial establishment in 1989. In conclusion, IPEC-J2, if cultured under defined species-specific conditions, forms a suitable model for investigating porcine paracellular intestinal barrier function. PMID:24260272

  8. Dynamical behavior caused by numerical dynamo simulations in a rotating spherical shell with the heterogeneous outer boundary

    NASA Astrophysics Data System (ADS)

    Nakagawa, T.; Aubert, J.

    2013-12-01

    We use numerical dynamo simulations in a rotating spherical shell to investigate the thermal structure in the core influenced by the heterogeneous top boundary. The experimental study in a rotating hemispherical shell with huge anomalous heterogeneous outer boundary suggested that the ';front' structure caused by huge amplitude of thermal anomalies at the top boundary but not checked in the various dynamo regimes [Sumita and Olson, 2002], which predicted that the major physical mechanism for the ';front' structure could be understood by the thermal wind balance. Aurnou and Aubert [2011] suggested that there would be several regimes when the heterogeneous condition at the top boundary was imposed in numerical dynamo simulations but not investigated thermal structure in the core to check the experimental consequences as well as the regime transition between convective and boundary modulated dynamo regimes. Here we use two Ekman number (10^-4 and 3x10^-5) and fixed magnetic and thermal Prandtl number (the unity) with varying various Rayleigh number defined the amplitude of lateral variation of heat flux across the top boundary. The pattern of heterogeneous boundary condition is used as (l,m)=(2,2). The two or more ';fronts' are found in imposed heterogeneous boundary at least. These fronts are very small time-dependence for their positions with large lateral temperature variations near fronts. This means that the ';front' structure could be found in the MHD dynamo system as well as non-magnetic cases shown in Sumita and Olson [2002] because the Lorentz force contribution to thermal wind balance seems to be very weak compared to the buoyancy flux to balance the Coriolis effect. More information will be provided in the presentation.

  9. Analysis and calibration of the gyro bias caused by geomagnetic field in a dual-axis rotational inertial navigation system

    NASA Astrophysics Data System (ADS)

    Cai, Qingzhong; Yang, Gongliu; Song, Ningfang; Yin, Hongliang; Liu, Yiliang

    2016-10-01

    A rotational inertial navigation system (RINS) has been wildly used in long term marine navigation. In a dual-axis RINS, with all constant biases averaged out, the errors which can not be averaged out become the main error source. In this paper, the gyro geomagnetic biases of a dual-axis RINS are modelled, analysed and calibrated. The gyro geomagnetic biases are proved unable to be averaged out, but can be modulated to be a constant value in the navigation frame. A slope error term of longitude error is found to be caused by gyro geomagnetic biases in north and upward directions, which increases linearly with time and is remarkable in long term navigation. Thus, a calibration method based on least square regression is proposed to compensate the slope error term. Laboratory and sailing experimental results show that the divergence speed of longitude error can be effectively slowed down by the compensation of gyro geomagnetic biases. In long term independent navigation, the position accuracy of dual-axis RINS is improved about 50% by the calibration method proposed in this paper.

  10. Effects of scapula-upward taping using kinesiology tape in a patient with shoulder pain caused by scapular downward rotation.

    PubMed

    Kim, Byeong-Jo; Lee, Jung-Hoon

    2015-02-01

    [Purpose] The aim of this study was to evaluate the effects of scapula-upward taping (SUT) in a patient with shoulder pain caused by scapular downward rotation (SDR). [Subject] A 26-year-old male with SDR experienced severe pain in the left shoulder when he lifted his left upper extremity to hold the handle in a bus and during and after push-up exercise. [Methods] The patient underwent SUT for a period of 1 month, 5 times per week, for an average of 9 h/d. [Results] The patient's radiographs showed that the degree of SDR had decreased; the left shoulder pain also decreased in the resting state and during and after push-up exercise. The manual muscle strength test grades of the upper trapezius, lower trapezius, and serratus anterior had increased. The patient was able to lift the left upper extremity to hold the handle in a bus and perform the push-up exercise without experiencing any pain. [Conclusion] Repeated SUT application may be a beneficial treatment method for alleviating the degree of SDR and shoulder pain in SDR patients.

  11. Jejunal mucosal immunoglobulins and complement in untreated coeliac disease.

    PubMed

    Scott, B B; Scott, D G; Losowsky, M S

    1977-04-01

    Jejunal immunofluorescence studies have shown that there is a significantly increased incidence of extracellular IgA and complement in the basement membrane zone and lamina propria of untreated adult coeliac patients compared to coeliac patients on a gluten-free diet. IgG was also demonstrated with complement, particularly in the untreated patients. These findings, taken together with those of other studies, suggest that a local antibody-antigen reaction involving IgA and complement may be responsible for the ongoing mucosal damage in untreated coeliac disease as well as for the acute damage following gluten challenge of the treated patient. Furthermore, consequent upon this damage there may be a secondary IgG antibody response, possibly reticulin antibody, contributing to the mucosal damage.

  12. Jejunal atresia with absent mesentery and a helical ileum.

    PubMed

    Zerella, J T; Martin, L W

    1976-11-01

    Of 59 infants with jejunoileal atresia, seven presented with absence of mesentery, the main superior mesenteric artery ceasing to exist beyond the origin of the right colic or ileocolic artery, and a helical ileum. This distinctive form of jejunal atresia has been recognized with increasing frequency in recent years. Distal to the atresia, the small bowel receives its blood supply retrograde from an artery derived from the ileocolic or right colic arcades, and the ileum coils around its nutrient artery in an "apple peel" or "Christmas tree" deformity. The first three patients in this report died. The lastion, but they recovered as their malabsorption gradually disappeared. The treatment includes resection of the dilated bowel, as in other atresias. Resection of part of the distal bowel may be required for additional atresias or for poor vascularity with questionable viability. Postoperative malabsorption generally requires intravenous hyperalimentation.

  13. FIXING JEJUNAL MANEUVER TO PREVENT PETERSEN HERNIA IN GASTRIC BYPASS

    PubMed Central

    MURAD-JUNIOR, Abdon José; SCHEIBE, Christian Lamar; CAMPELO, Giuliano Peixoto; de LIMA, Roclides Castro; MURAD, Lucianne Maria Moraes Rêgo Pereira; dos SANTOS, Eduardo Pachu Raia; RAMOS, Almino Cardoso; VALADÃO, José Aparecido

    2015-01-01

    Background : Among Roux-en-Y gastric bypass complications is the occurrence of intestinal obstruction by the appearance of internal hernias, which may occur in Petersen space or the opening in mesenteric enteroenteroanastomosis. Aim : To evaluate the efficiency and safety in performing a fixing jejunal maneuver in the transverse mesocolon to prevent internal hernia formation in Petersen space. Method : Two surgical points between the jejunum and the transverse mesocolon, being 5 cm and 10 cm from duodenojejunal angle are made. In all patients was left Petersen space open and closing the opening of the mesenteric enteroenteroanastomosis. Results : Among 52 operated patients, 35 were women (67.3%). The age ranged 18-63 years, mean 39.2 years. BMI ranged from 35 to 56 kg/m2 (mean 40.5 kg/m2). Mean follow-up was 15.1 months (12-18 months). The operative time ranged from 68-138 min. There were no intraoperative complications, and there were no major postoperative complications and no reoperations. The hospital stay ranged from 2-3 days. During the follow-up, no one patient developed suspect clinical presentation of internal hernia. Follow-up in nine patients (17.3%) showed asymptomatic cholelithiasis and underwent elective laparoscopic cholecystectomy. During these procedures were verified the Petersen space and jejunal fixation. In all nine, there was no herniation of the jejunum to the right side in Petersen space. Conclusion : The fixation of the first part of the jejunum to left side of the transverse mesocolon is safe and effective to prevent internal Petersen hernia in RYGB postoperatively in the short and medium term. It may be interesting alternative to closing the Petersen space. PMID:26537279

  14. Jejunal diverticular disease complicated by enteroliths: Report of two different presentations

    PubMed Central

    Chugay, Paul; Choi, John; Dong, Xiang Da

    2010-01-01

    Jejunal diverticula are quite rare. Furthermore, small bowel diverticular disease resulting in enteroliths can lead to complications necessitating surgical intervention. In this manuscript, we report two presentations of jejunal diverticulum with complications from enteroliths followed by a review of the literature. The first case was that of a 79-year-old male who presented with abdominal pain and was found, on computed tomography (CT) scan, to have evidence of intestinal perforation. A laparotomy showed that he had perforated jejunal diverticulitis. The second case was that of an 89-year-old female who presented with recurrent episodes of bowel obstruction. A laparotomy showed that she had an enterolith impacted in her jejunum in the presence of significant diverticular disease. Although a rare entity, familiarity with jejunal diverticular disease, its complications, and its management, should be part of every surgeon’s base of knowledge when considering abdominal pathology. PMID:21160831

  15. Percutaneous Retrograde Sclerotherapy for Refractory Bleeding of Jejunal Varices: Direct Injection via Superficial Epigastric Vein

    SciTech Connect

    Nakata, Manabu Nakata, Waka; Isoda, Norio Yoshizawa, Mitsuyo; Sugimoto, Hideharu

    2012-02-15

    Small-bowel varices are rare and almost always occur in cases with portal hypertension. We encountered a patient with bleeding jejunal varices due to liver cirrhosis. Percutaneous retrograde sclerotherapy was performed via the superficial epigastric vein. Melena disappeared immediately after treatment. Disappearance of jejunal varices was confirmed by contrast-enhanced computed tomography. After 24 months of follow-up, no recurrent melena was observed.

  16. [Usefulness of endoscopically guided nasogastric-jejunal feeding tube placement in a case of aspiration pneumonia due to postgastrectomy].

    PubMed

    Tamura, Kosei; Totsuka, Osamu; Tamura, Jun'ichi

    2015-01-01

    A 79-year-old man with a history of gastrectomy with Billroth II reconstruction 27 years previously was admitted to our hospital due to recurrent pneumonia. Because he had dysphagia and had frequently developed pneumonia over the course of a year, enteral nutrition via nasogastric tube was initiated approximately six months before admission. The clinical and computed tomography findings showed that the cause of pneumonia was aspiration of tube feeding nutrients due to gastroesophageal reflux. To prevent gastroesophageal reflux, he was continuously kept in a 30-degree or greater reclining position. However, gastroesophageal reflux was seen at an injection rate of 50 ml/h or greater. After we inserted a nasogastric-jejunal feeding tube guided by endoscopy, gastroesophageal reflux, dumping syndrome and diarrhea were not seen up to an injection rate of 300 ml/h. Endoscopically guided nasogastric-jejunal feeding tube placement is a simple method and may be useful for patients with aspiration pneumonia due to postgastrectomy. Moreover, long-term postgastrectomy patients appear to tolerate the postopyloric injection of enteral nutrition. Because the number of elderly patients who have dysphagia with postgastrectomy is increasing, these findings provide a basis for treatment in elderly medical settings.

  17. [Usefulness of endoscopically guided nasogastric-jejunal feeding tube placement in a case of aspiration pneumonia due to postgastrectomy].

    PubMed

    Tamura, Kosei; Totsuka, Osamu; Tamura, Jun'ichi

    2015-01-01

    A 79-year-old man with a history of gastrectomy with Billroth II reconstruction 27 years previously was admitted to our hospital due to recurrent pneumonia. Because he had dysphagia and had frequently developed pneumonia over the course of a year, enteral nutrition via nasogastric tube was initiated approximately six months before admission. The clinical and computed tomography findings showed that the cause of pneumonia was aspiration of tube feeding nutrients due to gastroesophageal reflux. To prevent gastroesophageal reflux, he was continuously kept in a 30-degree or greater reclining position. However, gastroesophageal reflux was seen at an injection rate of 50 ml/h or greater. After we inserted a nasogastric-jejunal feeding tube guided by endoscopy, gastroesophageal reflux, dumping syndrome and diarrhea were not seen up to an injection rate of 300 ml/h. Endoscopically guided nasogastric-jejunal feeding tube placement is a simple method and may be useful for patients with aspiration pneumonia due to postgastrectomy. Moreover, long-term postgastrectomy patients appear to tolerate the postopyloric injection of enteral nutrition. Because the number of elderly patients who have dysphagia with postgastrectomy is increasing, these findings provide a basis for treatment in elderly medical settings. PMID:26700781

  18. Measurements of tissue oxygen tension in vascularised jejunal autografts in pigs.

    PubMed

    Nielsen, I M; Riis, A; Jahn, H; Gottrup, F

    1995-12-01

    Tissue oxygen measurements were evaluated as a monitor of the jejunal flap in seven female landrace pigs. A small polarographic sensor (diameter 0.55 mm) was used in which interstitial tissue oxygen tension was measured continuously in a jejunal flap and a muscle flap (rectus abdominis) during arterial and venous occlusion. Mean (SEM) tissue oxygen tension in the two types of flap were 44(9) mmHg (jejunal flap) and 47(8) mmHg (rectus flap). After arterial occlusion for 30 minutes the values dropped to 17(4) mmHg for the jejunal flap and 12(2) mmHg for the muscle flap. The decline became significant after five minutes. During venous occlusion (30 minutes) the values fell to 20(4) mmHg and 14(1) mmHg. The arterial occlusion was undetectable by the naked eye, but the enteric tissue after venous occlusion became severely congested and blue-black in colour. The condition returned to normal after release of the clamp. We conclude that direct measurement of tissue oxygen tension in a jejunal flap is a reliable method of detecting impaired perfusion. This method may in the future be used to monitor vascularised jejunal autografts. PMID:8771255

  19. On the determination of heliographic positions and rotation velocities of sunspots. II - Systematic effects caused by the Wilson depression

    NASA Astrophysics Data System (ADS)

    Balthasar, H.; Woehl, H.

    1983-10-01

    Using sunspot positions of small sunspots observed at Debrecen and Locarno as well as positions of recurrent sunspots taken from the Greenwich Photoheliographic Results (1940-1976) the influence of the Wilson depression on the rotation velocities was investigated. It was found that the Wilson depression can be determined by minimizing errors of the rotation velocities or minimizing the differences of rotation velocities determined from disk passages and central meridian passages. The Wilson depressions found were between 765 km and 2500 km for the first sample while they were between 0 km and several 1000 km for the second sample. The averaged Wilson depression for the second sample is between 500 km and 965 km depending on the reduction method. A dependence of the Wilson depression on the age of the spots investigated seems not to exist.

  20. Tilted geostrophic convection in icy world oceans caused by the horizontal component of the planetary rotation vector

    NASA Astrophysics Data System (ADS)

    Goodman, J. C.

    2012-12-01

    The Coriolis force provides dominant control over the motion of atmospheres and oceans, both on Earth and on many other worlds. At any point on a planet's surface, the planetary rotation vector has both a vertical component and a horizontal (north-south) component. We typically ignore the horizontal component, which is justified if vertical motions are hydrostatic and the fluid is relatively shallow. Neither of these conditions is true for hydrothermal convection within the thick ocean layers of Europa and other icy worlds. Using the MITGCM ocean model, we explore the behavior of buoyant hydrothermal plumes in a deep unstratified ocean, including both components of the planetary rotation vector. We find that warm water does not rise vertically: instead, it spirals along the axis of planetary rotation. Eddies form which are tilted with respect to the local vertical, but parallel to the rotation axis: turbulent exchange of heat between these canted eddies carries the warm water toward the surface. This is not an entirely new idea: however, the implications for icy worlds have not been previously discussed. We observe that when these tilted plumes heat the ice layer above the ocean, the heating "footprint" of these tilted plumes will be more circular near the pole, more ellipsoidal in the tropics. If surface features of the ice crust were created by plume heating, their shapes ought to show consistent latitude trends. Also, we observe that if warm fluid were totally constrained to move along the planetary rotation axis, geothermal heat generated in the icy world's interior could never reach the ice crust near the equator. (For Europa, the "forbidden zone" could extend as far as +/- 20-25° latitude.) In practice, we find that turbulent eddies do allow heat to move perpendicular to the rotation vector, so the "forbidden zone" is not a tight constraint; still, it may affect the overall heating pattern of icy world crusts. Snapshot of ascent of buoyant hydrothermal plume

  1. A ``WET Dog" Tunneling Motion as the Cause for the Doubled Rotational Spectrum of 1-IodononaFluorobutane

    NASA Astrophysics Data System (ADS)

    Bailey, W. C.; Bohn, R. K.; Grubbs, G. S. Grubbs, Ii; Kisiel, Z.; Cooke, S. A.

    2013-06-01

    A chirped pulse Fourier transform microwave spectrometer has been used to record the rotational spectra of 1-iodononafluorobutane between 8 GHz and 12 GHz. The target compound was spectroscopically examined as it participated in a supersonic expansion of argon. The spectra recorded are dense owing in part to the small rotational constants, B + C ≈ 480 MHz, but also to hyperfine structure generated by the coupling of angular momenta of the iodine nucleus and the rotating molecular frame, e.g. mid χ_{ab} mid ≈ 1200 MHz. Notably all of the hyperfine components were observed as doublets. It is postulated that this doubling effect is the result of a low barrier, double minimum potential between two mirror image transoid structures. The tunneling motion between these structures resembles that of a ``wet dog" shaking itself dry. Numerous transitions are shifted in frequency and it is proposed that the density of rotational energy levels from the two interacting states results in numerous perturbations to the energy levels involved. A preliminary spectral analysis of over 400 transitions will be presented, along with the results of supporting quantum mechanical calculations.

  2. Isolated Jejunal Perforation Following Bicycle Handlebar Injury in Adults: A Case Report

    PubMed Central

    Neofytou, Kyriakos; Michailidou, Maria; Petrou, Athanasios; Loizou, Sakis; Andreou, Charalampos

    2013-01-01

    The small intestine is the third in frequency intraperitoneal organ which is injured after blunt trauma of the abdomen. In most of the cases, this type of injuries is accompanied by other injuries, which make it more difficult to diagnose. Failure of diagnosis and delay in treating these injuries significantly increase the morbidity and mortality of these patients. Abdominal visceral injuries after flipping the handlebar of the bike are common in children. Such injuries can cause injury to both solid and hollow abdominal viscera. Unlike children, adults' abdominal visceral injuries after flipping the bike's handlebar are extremely rare. A 25-year-old man was admitted to our department due to progressively abdominal pain after an accident with the handlebar of his bike. The subsequent CT scan after per os administration of contrast medium revealed the presence of free intraperitoneal contrast. It is a rare case of jejunal perforation after flipping the handlebar of the bicycle which was treated by partial removal of the injured part of jejunum and end-to-end anastomosis. To the best of our knowledge this is the first time we describe such an injury with this mechanism to an adult. PMID:23984116

  3. Ex vivo absorption of thymol and thymol-β-D-glucopyranoside in piglet everted jejunal segments.

    PubMed

    Petrujkić, Branko T; Sedej, Ivana; Beier, Ross C; Anderson, Robin C; Harvey, Roger B; Epps, Sharon V R; Stipanovic, Robert D; Krueger, Nathan A; Nisbet, David J

    2013-04-17

    Food-producing animals are reservoirs of Campylobacter, a leading bacterial cause of human foodborne illness. The natural product thymol can reduce the survivability of Campylobacter, but its rapid absorption in the proximal gastrointestinal tract may preclude its use as a feed additive to reduce intestinal colonization of these pathogens. This work examined the ex vivo absorption of thymol and thymol-β-d-glucopyranoside in everted porcine jejunal segments, as the latter was hypothesized to be more resistant to absorption. A modified gas chromatography and extraction method was developed to determine 1.0-500 mg/L thymol. From 1 and 3 mM solutions, 0.293 ± 0.04 and 0.898 ± 0.212 mM thymol, respectively, p = 0.0347, were absorbed, and 0.125 ± 0.041 and 0.317 ± 0.143 mM thymol-β-d-glucopyranoside, respectively, p = 0.0892, were absorbed. Results indicate that thymol-β-d-glucopyranoside was absorbed 2.3 to 2.8 times less effectively than thymol, thus providing evidence that thymol-β-d-glucopyranoside may potentially be used as a feed additive to transport thymol to the piglet lower gut. PMID:23551201

  4. Glutamine supplementation does not improve protein synthesis rate by the jejunal mucosa of the malnourished rat.

    PubMed

    Tannus, Andrea Ferreira S; Darmaun, Dominique; Ribas, Durval F; Oliveira, José Eduardo D; Marchini, Julio Sergio

    2009-08-01

    It has been demonstrated that glutamine, a conditionally essential amino acid, improves nitrogen balance, acts as a stimulant of protein synthesis, and decreases proteolysis in myopathic children. In contrast, other studies have shown no beneficial effect of glutamine supplementation on burn victims or critically ill patients. Nonetheless, we hypothesized that glutamine supplementation would increase the fractional protein synthesis rate (FSR) in the jejunal mucosa of malnourished male Wistar rats. Thus, the objective of the present study was to test the effect of daily oral glutamine supplementation (0.42 g kg(-1) d(-1) for 14 days) on the FSR of the jejunal mucosa of healthy and malnourished rats. A 4-hour kinetic study with l-[1-(13)C]leucine was subsequently performed, and jejunal biopsies were obtained 1.5 cm from the Treitz angle and analyzed. Malnourished rats showed a 25% weight loss and increased urinary nitrogen excretion. Plasma amino acid concentration did not differ between groups. (13)C enrichment in plasma and jejunal cells was higher in the malnourished groups than in the healthy group. The FSR (percent per hour) was similar for the control and experimental groups (P > .05), with a mean range of 22%/h to 27%/h. Oral glutamine supplementation alone did not induce higher protein incorporation by the jejunal mucosa in malnourished rats, regardless of total food intake or the presence or absence of glutamine supplementation.

  5. Challenges of banding jejunal varices in an 8-year-old child

    PubMed Central

    Belsha, Dalia; Thomson, Mike

    2015-01-01

    Endoscoic variceal ligation (EVL) by the application of bands on small bowel varices is a relatively rare procedure in gastroenterology and hepatology. There are no previously reported paediatric cases of EVL for jejunal varices. We report a case of an eight-year-old male patient with a complex surgical background leading to jejunal varices and short bowel syndrome, presenting with obscure but profound acute gastrointestinal bleeding. Wireless capsule endoscopy and double balloon enteroscopy (DBE) confirmed jejunal varices as the source of bleeding. The commercially available variceal banding devices are not long enough to be used either with DBE or with push enteroscopes. With the use of an operating gastroscope, four bands were placed successfully on the afferent and efferent ends of the leads of the 2 of the varices. Initial hemostasis was achieved with obliteration of the varices after three separate applications. This case illustrates the feasibility of achieving initial hemostasis in the pediatric population. PMID:26722617

  6. Embolization therapy for bleeding from jejunal loop varices due to extrahepatic portal vein obstruction.

    PubMed

    Yoshimatsu, Rika; Yamagami, Takuji; Ishikawa, Masaki; Kajiwara, Kenji; Kakizawa, Hideaki; Hiyama, Eiso; Tashiro, Hirotaka; Murakami, Yoshiaki; Ohge, Hiroki; Awai, Kazuo

    2016-01-01

    Four patients underwent embolization therapy for hemorrhage from varices in the jejunal loop after choledochojejunostomy existing in hepatopetal collateral veins due to chronic extrahepatic portal vein obstruction through the afferent veins using microcoils and/or n-butyl cyanoacrylate. In all four patients, all afferent veins were successfully embolized and successful hemostasis was achieved without liver dysfunction. However, recurrence of the varices and rebleeding occurred within a year in two patients. Embolization for hemorrhage from varices in the jejunal loop after choledochojejunostomy through afferent veins is acceptable in terms of safety and is useful to achieve hemostasis in emergency circumstances. PMID:26330264

  7. Using an Atom Interferometer to Measure Changes in Tune-Out Wavelength caused by Rotation and Acceleration

    NASA Astrophysics Data System (ADS)

    Trubko, Raisa; Greenberg, James; St. Germaine, Michael T.; Gregoire, Maxwell D.; Hromada, Ivan; Holmgren, William F.; Cronin, Alexander D.

    2014-05-01

    Measurements of tune-out wavelengths made with an atom interferometer are shown to change by 150 pm due to inertial displacements. Because tune-out wavelengths can be measured with picometer precision in our laboratory, we explore how to use shifts in tune-out wavelengths to measure rotation rates with respect to an inertial frame. For example, measuring the earth's rotation rate with an uncertainty of 1% appears possible with this technique. The origin of shifts in measured tune-out wavelengths (λzero , lab) as compared to tune-out wavelengths in an inertial frame (λzero) is explained by dispersive inertial phase shifts, the vector dynamic polarizability αv (ω) , and dispersion compensation. An atom beam with a velocity spread and an ensemble of atomic spin states is required. Because accurate measurements of λzero can be used for reporting ratios of dipole matrix elements, we also discuss methods for reducing systematic errors in measurements of λzero.

  8. Differences in transcriptomic profile and IgA repertoire between jejunal and ileal Peyer's patches.

    PubMed

    Levast, Benoît; De Monte, Michèle; Melo, Sandrine; Chevaleyre, Claire; Berri, Mustapha; Salmon, Henri; Meurens, François

    2010-02-01

    In many species such as sheep and pig, there are two types of Peyer's patches (PP): several discrete patches in the jejunum and a long and continuous patch in the ileum. Most of the immunoglobulin A in the gut is generated by B-cells in the PP germinal centers. Moreover, swine like ovine ileal PP might be important for antigen independent B-cell repertoire diversification. We examined, by quantitative real-time PCR, the expression of 36 transcripts of antimicrobial peptides, chemokines, interleukines, Toll-like receptors and transcription factors from both PP and we highlighted the differences by a principal component analysis. Ileal PP was characterized by a higher mRNA expression of CCL28, IL5, IL10, TLR2 and TLR4 while jejunal PP showed higher mRNA expression of antimicrobial peptides, CCL25, FOXP3, IL4, T-Bet, TSLP and SOCS2. Then, we analyzed some VDJ rearrangements to assess immunoglobulin repertoire diversity in jejunal and ileal PP from weaned piglets. The IgA and IgM repertoires were more diverse in ileal than in jejunal piglet PP. All these results could be related to the rarefaction of interfollicular T-cell zone and the presence in ileal versus jejunal lumen of a more diversified microflora. These findings shed a light on the functional differences between both PP.

  9. Adult jejunojejunal intussusception in the face of jejunal adenocarcinoma: two infrequently encountered entities.

    PubMed

    Elmoghrabi, Adel; Mohamed, Mohamed; McCann, Michael; Sachwani-Daswani, Gul

    2016-01-01

    Adult intussusception and small bowel adenocarcinoma are rarely encountered together. Intussusception should be considered in the differential diagnosis of adult patients presenting with abdominal pain, especially those with unremitting symptoms. Concomitant anaemia should lower the threshold for suspicion of underlying malignancy. Jejunal adenocarcinoma represents a rare, but possible aetiology. PMID:26961563

  10. Ischemic jejunal stenosis and blind loop syndrome after blunt abdominal trauma.

    PubMed

    Isaacs, P; Rendall, M; Hoskins, E O; Missen, G A; Sladen, G E

    1987-02-01

    One month after suffering blunt abdominal trauma a patient developed severe steatorrhea and profound weight loss in association with an ischemic distal jejunal stricture and blind loop syndrome. Evidence for a partial mesenteric tear was found at resection of the stricture, which resulted in complete cure.

  11. Jejunal administration of glucose enhances acyl ghrelin suppression in obese humans.

    PubMed

    Tamboli, Robyn A; Sidani, Reem M; Garcia, Anna E; Antoun, Joseph; Isbell, James M; Albaugh, Vance L; Abumrad, Naji N

    2016-07-01

    Ghrelin is a gastric hormone that stimulates hunger and worsens glucose metabolism. Circulating ghrelin is decreased after Roux-en-Y gastric bypass (RYGB) surgery; however, the mechanism(s) underlying this change is unknown. We tested the hypothesis that jejunal nutrient exposure plays a significant role in ghrelin suppression after RYGB. Feeding tubes were placed in the stomach or jejunum in 13 obese subjects to simulate pre-RYGB or post-RYGB glucose exposure to the gastrointestinal (GI) tract, respectively, without the confounding effects of caloric restriction, weight loss, and surgical stress. On separate study days, the plasma glucose curves obtained with either gastric or jejunal administration of glucose were replicated with intravenous (iv) infusions of glucose. These "isoglycemic clamps" enabled us to determine the contribution of the GI tract and postabsorptive plasma glucose to acyl ghrelin suppression. Plasma acyl ghrelin levels were suppressed to a greater degree with jejunal glucose administration compared with gastric glucose administration (P < 0.05). Jejunal administration of glucose also resulted in a greater suppression of acyl ghrelin than the corresponding isoglycemic glucose infusion (P ≤ 0.01). However, gastric and isoglycemic iv glucose infusions resulted in similar degrees of acyl ghrelin suppression (P > 0.05). Direct exposure of the proximal jejunum to glucose increases acyl ghrelin suppression independent of circulating glucose levels. The enhanced suppression of acyl ghrelin after RYGB may be due to a nutrient-initiated signal in the jejunum that regulates ghrelin secretion. PMID:27279247

  12. Multiple Primary Dedifferentiated Liposarcoma of the Jejunal Mesentery: A Case Report and Review of Literature.

    PubMed

    Vats, Manu; Pandey, Diwakar; Ahlawat, Himani; Akhtar, Azaz; Singh, Nain

    2016-01-01

    Liposarcoma arising primarily from the intestinal mesentery is a rare malignancy. Malignancy is said to be synchronous when there is occurrence of two or more tumours that have not spread from a common site or recurred and show no evidence of metastasis. Multiple synchronous primary liposarcoma of the mesentery is a very unusual clinical finding. Here, we report a rare case of synchronous multiple primary dedifferentiated liposarcoma of jejunal mesentery in a 36-year-old female patient. Radiological investigations aided in making a provisional diagnosis of an ovarian malignancy. A staging laparotomy was performed and general surgeon's help was sought due to the presence of three separate jejunal mesenteric masses of sizes 8x6 cms, 6x6 cms and 25x20 cms respectively. Complete excision of mesenteric masses with one feet of involved jejunum was done and a jejuno-jejunal anastomosis made. The histopathology report was indicative of multiple dedifferentiated liposarcoma of jejunal mesentery. Postoperatively patient received Doxorubicin, Dacarbazine and Ifosfamide based adjuvant chemotherapy in view of poorly differentiated tumour. Patient remains tumour free for the last 12 months of follow up. PMID:26894164

  13. Gastrointestinal monitor: automatic titration of jejunal inflow to match peristaltic outflow.

    PubMed

    Moss, Gerald; Posada, Jose G

    2007-06-15

    A peristaltic gradient insures that chyme normally removed from the jejunal feeding site continues to be propelled caudad. The trigger for iatrogenic "feeding intolerance" is the inadvertently overwhelming of the jejunum's peristaltic outflow, even momentarily. Even minimum local stasis can stimulate a vagal reflex response. Motility of the sluggish gut further slows, leading to generalized abdominal distention, malaise, immobility, and impaired respiratory mechanics. Vagal vascular reflexes could explain the 1:1000 incidence of bowel necrosis for jejunally fed patients. We developed a clinical regimen that continuously "checks for residual" at the enteral feeding site, monitoring the adequacy of emptying. The jejunal inflow automatically is titrated to match peristaltic outflow if the latter cannot keep up. Intermittent suction aspirates the feeding catheter into a plastic chamber for 30 s. All swallowed air is removed efficiently within the close confines of the jejunal segment, without wasting digestive juices. The degassed aspirate is returned by gravity with the feedings during the second half of the 1-min cycle, unless incipient excess (>or=20 mL) fluid overflows. Only this relatively small volume of potentially excess fluid is discarded, forestalling the local distention. All patients tolerated immediate feeding without discomfort or abdominal distention, including three that had esophageal resection (including vagotomy) for carcinoma. Postoperative full enteral nutrition can be achieved quickly and safely with minimum attention, despite initially marginal gastrointestinal function. PMID:17509263

  14. Electroacupuncture at ST37 Enhances Jejunal Motility via Excitation of the Parasympathetic System in Rats and Mice

    PubMed Central

    Yuan, Mengqian; Li, Yuqin; Wang, Yidan; Zhang, Na; Hu, XuanMing; Yin, Yin; Zhu, Bing

    2016-01-01

    Background. The roles of the sympathetic and parasympathetic systems in mediating the effect of electroacupuncture (EA) at ST37 on jejunal motility have yet to be demonstrated. Aim. We used rats and mice to investigate the effect and mechanism of action of EA at ST37 on jejunal motility. Methods. Jejunal motility was recorded by a balloon placed in the jejunum and connected to a biological signal collection system through a transducer. The effects of EA (3 mA) at ST37 were evaluated in Sprague-Dawley rats without drugs and with the administration of clenbuterol, propranolol, acetylcholine, and atropine. Further, the efficacy of EA at different intensities (1/2/4/6/8 mA) was measured in wild-type mice and β1β2−/− mice and M2M3−/− mice. Results. In Sprague-Dawley rats, the excitatory effect of EA at ST37 on jejunal motility disappeared in the presence of the muscarinic receptor antagonist atropine. EA at ST37 was less effective in M2M3−/− mice than in wild-type mice. Furthermore, to a certain extent, there existed “intensity-response” relationship between jejunal motility and EA. Conclusions. EA at ST37 can enhance jejunal motility in rats and mice mainly via excitation of the parasympathetic pathway. There is an “intensity-response” relationship between EA and effect on jejunal motility.

  15. The ileal brake--inhibition of jejunal motility after ileal fat perfusion in man.

    PubMed Central

    Spiller, R C; Trotman, I F; Higgins, B E; Ghatei, M A; Grimble, G K; Lee, Y C; Bloom, S R; Misiewicz, J J; Silk, D B

    1984-01-01

    The possibility that malabsorbed fat passing through the human ileum exerts an inhibitory feedback control on jejunal motility has been investigated in 24 normal subjects by perfusing the ileum with a fat containing solution designed to produce ileal luminal fat concentrations similar to those in steatorrhoea (30-40 mg/ml). Mean transit times through a 30 cm saline perfused jejunal segment were measured by a dye dilution technique. Thirty minutes after ileal fat perfusion, mean transit times rose markedly to 18.9 +/- 2.5 minutes from a control value of 7.5 +/- 0.9 minutes (n = 5; p less than 0.05). This was associated with an increase in volume of the perfused segment which rose to 175.1 +/- 22.9 ml (control 97.6 +/- 10.3 ml, n = 5; p less than 0.05). Transit times and segmental volumes had returned towards basal values 90 minutes after completing the fat perfusion. Further studies showed that ileal fat perfusion produced a pronounced inhibition of jejunal pressure wave activity, percentage duration of activity falling from a control level of 40.3 +/- 5.0% to 14.9 +/- 2.8% in the hour after ileal perfusion (p less than 0.01). Ileal fat perfusion was associated with marked rises in plasma enteroglucagon and neurotensin, the peak values (218 +/- 37 and 68 +/- 13.1 pmol/l) being comparable with those observed postprandially in coeliac disease. These observations show the existence in man of an inhibitory intestinal control mechanism, whereby ileal fat perfusion inhibits jejunal motility and delays caudal transit of jejunal contents. PMID:6706215

  16. Did clockwise rotation of Antarctica cause the break-up of Gondwanaland? An investigation in the 'deep-keeled cratons' frame for global dynamics

    NASA Astrophysics Data System (ADS)

    Osmaston, M. F.

    2012-04-01

    Introduction. The 'deep-keeled cratons' frame for global dynamics is the result of seeking Earth-behaviour answers to the following outside-the-box proposition:- "If cratons have tectospheric keels that reach or approach the 660 km discontinuity, AND the 660 level is an effective barrier to mantle circulation, then obviously (i) when two cratons separate, the upper mantle to put under the nascent ocean must arrive by a circuitous route and, conversely, (ii) if they approach one another, the mantle volume that was in between them must get extruded sideways." Surprisingly it has turned out [1 - 4] that Earth dynamical behaviour for at least the past 150 Ma provides persuasive affirmation of both these expectations and that there is a rational petrological explanation for the otherwise-unexpected immobility of subcratonic material to such depths [5 - 7]. Clockwise rotation of Antarctica? This contribution greatly amplifies my original plate dynamical arguments for suggesting [8] that such rotation is ongoing. Convection is unsuited to causing rotation about a pole within the plate so, as noted then, a gearwheel-like linkage to Africa at the SWIR would provide its clearly CCW (Biscay-Caucasus) relationship to the Mediterranean belt for the past 100 Ma, also seen in its separation from South America. Gearwheel-like linkage of motion requires the presence of some kind of E-W restraint further north. In that case it was the N Africa/Arabia involvement in the Alpide belt, but the earlier opening of the central Atlantic by the eastward motion of Africa, suggests its rigid Gondwanan attachment to Antarctica rotation at that time, with little constraint in the north. Further east, the seafloor data show that Australia-Antarctica separation involved no such opposite rotational linkage, so, with no E-W mechanical constraint in the north by Indonesia, they must have rotated together, as is recorded by Australia's eastward motion to generate the Mesozoic seafloor at its western

  17. Unique paleopathology in a pre-Columbian mummy remnant from Southern Peru--severe cervical rotation trauma with subluxation of the axis as cause of death.

    PubMed

    Sokiranski, Roman; Pirsig, Wolfgang; Richter, Hans-Peter; Lösch, Sandra; Struck, Ulrich; Nerlich, Andreas G

    2011-03-01

    We describe the multidisciplinary findings in a pre-Columbian mummy head from Southern Peru (Cahuachi, Nazca civilisation, radiocarbon dating between 120 and 750 AD) of a mature male individual (40-60 years) with the first two vertebrae attached in pathological position. Accordingly, the atlanto-axial transition (C1/C2) was significantly rotated and dislocated at 38° angle associated with a bulging brownish mass that considerably reduced the spinal canal by circa 60%. Using surface microscopy, endoscopy, high-resolution multi-slice computer tomography, paleohistology and immunohistochemistry, we identified an extensive epidural hematoma of the upper cervical spinal canal-extending into the skull cavity-obviously due to a rupture of the left vertebral artery at its transition between atlas and skull base. There were no signs of fractures of the skull or vertebrae. Histological and immunohistochemical examinations clearly identified dura, brain residues and densely packed corpuscular elements that proved to represent fresh epidural hematoma. Subsequent biochemical analysis provided no evidence for pre-mortal cocaine consumption. Stable isotope analysis, however, revealed significant and repeated changes in the nutrition during his last 9 months, suggesting high mobility. Finally, the significant narrowing of the rotational atlanto-axial dislocation and the epidural hematoma probably caused compression of the spinal cord and the medulla oblongata with subsequent respiratory arrest. In conclusion, we suggest that the man died within a short period of time (probably few minutes) in an upright position with the head rotated rapidly to the right side. In paleopathologic literature, trauma to the upper cervical spine has as yet only very rarely been described, and dislocation of the vertebral bodies has not been presented.

  18. Interference fringes of m=0 spin states under the Majorana transition caused by rapid half-rotation of a magnetic field

    NASA Astrophysics Data System (ADS)

    Takahashi, Atsushi; Morinaga, Atsuo

    2010-04-01

    The phase shift and visibility of fringes in the Ramsey atom interferometer composed of the |F=1,mF=0> and |F=2,mF=0> states were examined systematically for rapid half-rotation of the magnetic field. It was verified that the phase shifts by π rad in the adiabatic regime, but it does not shift from the original one in the nonadiabatic regime. These results support Robbins and Berry’s claim [J. M. Robbins and M. V. Berry, J. Phys. A 27, L435 (1994)]. The fact that the interference fringes disappear in the intermediate regime and reappear in the nonadiabatic regime can be explained by the Majorana transition caused by a rapid reverse of the magnetic field.

  19. Jejunal intussusception caused by metastasis of a giant cell carcinoma of the lung

    PubMed Central

    Fujii, Yuki; Homma, Shigenori; Yoshida, Tadashi; Taketomi, Akinobu

    2016-01-01

    A 55-year-old woman was admitted to our hospital reporting of nausea, vomiting and anorexia. One month before admission, she had been diagnosed with lung cancer with intestinal metastasis. A CT scan confirmed intussusception due to intestinal metastasis and she underwent emergency laparoscopic surgery followed by resection of the primary lung cancer. Histopathological findings of the intestinal specimen suggested the metastasis was from a giant cell carcinoma of the lung, which had extensive necrosis. She was still alive without recurrence 11 months after the first surgery. Giant cell carcinoma of the lung is a rare type of non-small cell carcinoma and intestinal metastasis is one of the unique features. This type of tumour has such aggressive characteristics that oncological prognosis is reported to be extremely poor. In our case, however, complete surgical resection of both primary and metastatic tumours might result in a better outcome than has been reported. PMID:27485876

  20. Jejunal intussusception caused by metastasis of a giant cell carcinoma of the lung.

    PubMed

    Fujii, Yuki; Homma, Shigenori; Yoshida, Tadashi; Taketomi, Akinobu

    2016-01-01

    A 55-year-old woman was admitted to our hospital reporting of nausea, vomiting and anorexia. One month before admission, she had been diagnosed with lung cancer with intestinal metastasis. A CT scan confirmed intussusception due to intestinal metastasis and she underwent emergency laparoscopic surgery followed by resection of the primary lung cancer. Histopathological findings of the intestinal specimen suggested the metastasis was from a giant cell carcinoma of the lung, which had extensive necrosis. She was still alive without recurrence 11 months after the first surgery. Giant cell carcinoma of the lung is a rare type of non-small cell carcinoma and intestinal metastasis is one of the unique features. This type of tumour has such aggressive characteristics that oncological prognosis is reported to be extremely poor. In our case, however, complete surgical resection of both primary and metastatic tumours might result in a better outcome than has been reported. PMID:27485876

  1. Circadian variation of the cell proliferation in the jejunal epithelium of rats at weaning phase.

    PubMed

    Gomes, J R; Pereira, A A M; Barth, L; Silva, J S; Leite, M L; Wille, A C M; Soares, M A M

    2005-06-01

    Circadian variation in cell proliferation of the jejunal epithelium of 18-day-old rats was studied using the 2-h arrested metaphase score and crypt isolation method. A continuous decrease in the arrested metaphases occurred from 07.00 h to 13.00 h. From 17.00 h arrested metaphase values increased and were maintained at the higher level during the dark period as showed by Cosinor analyses (P < 0.05). These results indicate that in the young rat there is already a circadian variation in jejunal epithelial cell proliferation as early as 18 days. We can even suggest that the presence of a circadian rhythm at weaning contributes to the steady state of cell proliferation in the intestinal epithelium observed in adult life.

  2. Effect of pinaverium bromide on jejunal motility and colonic transit time in healthy humans.

    PubMed

    Bouchoucha, M; Salles, J P; Fallet, M; Frileux, P; Cugnenc, P H; Barbier, J P

    1992-01-01

    Pinaverium bromide is a specific calcium channel blocker used in the treatment of irritable bowel syndrome (IBS) for its spasmolytic activity. The aim of the present study was to evaluate the effect of orally administered pinaverium bromide on jejunal motility and total and segmental colonic transit time in control subjects. Gastrointestinal studies were performed in 10 healthy volunteers (30 +/- 3 years), before and after a treatment phase of 14 days (150 mg/d). Jejunal motility was measured by prolonged manometry (14 h) and colonic transit time by a multiple ingestion, single marker technique. No significant modification of phase III of the migrating motor complexes was demonstrated. On the contrary, a significant (p < 0.01) but weak decrease of the frequency of contraction was found. Unlike previous studies, no decrease of total or segmental colonic transit time was demonstrated. PMID:1421047

  3. Electroacupuncture at ST25 inhibits jejunal motility: Role of sympathetic pathways and TRPV1

    PubMed Central

    Yu, Zhi; Zhang, Na; Lu, Chun-Xia; Pang, Ting-Ting; Wang, Kai-Yue; Jiang, Jing-Feng; Zhu, Bing; Xu, Bin

    2016-01-01

    AIM: To investigate whether electroacupuncture (EA) at ST25 affects jejunal motility in vivo and if so, whether a sympathetic pathway is involved. METHODS: Jejunal motility was assessed using a manometric balloon placed in the jejunum approximately about 3-5 cm away from the suspensory ligament of the duodenum in anesthetized animals. The effects of EA at ST25 were measured in male Sprague-Dawley rats, some of which were treated with propranolol or clenbuterol (EA intensities: 1, 3, 5, 7, and 9 mA), and in male transient receptor potential vanilloid-1 (TRPV1) (capsaicin receptor) knockout mice (EA intensities: 1, 2, and 4 mA). RESULTS: Anesthetized rats exhibited three types of fasting jejunal motor patterns (types A, B, and C), and only type C rats responded to EA stimulation. In type C rats, EA at ST25 significantly suppressed the motor activity of the jejunum in an intensity-dependent manner. The inhibitory effect of EA was weakened by propranolol (β adrenoceptor antagonist) and disappeared with clenbuterol (β adrenoceptor agonist) induced inhibition of motility, suggesting that the effect of EA on motility is mediated via a sympathetic pathway. Compared with wild-type mice, EA at ST25 was less effective in TRPV1 knockout mice, suggesting that this multi-modal sensor channel participates in the mechanism. CONCLUSION: EA at ST25 was found to inhibit jejunal motility in an intensity-dependent manner, via a mechanism in which sympathetic nerves and TRPV1 receptors play an important role. PMID:26855542

  4. Substrate metabolism in isolated rat jejunal epithelium. Analysis using /sup 14/C-radioisotopes

    SciTech Connect

    Mallet, R.T.

    1986-01-01

    The jejunal epithelium absorbs nutrients from the intestinal lumen and is therefore the initial site for metabolism of these compounds. The purpose of this investigation is to analyze substrate metabolism in a preparation of jejunal epithelium relatively free of other tissues. Novel radioisotopic labelling techniques allow quantitation of substrate metabolism in the TCA cycle, Embden-Meyerhof (glycolytic) pathway, and hexose monophosphate shunt. For example, ratios of /sup 14/CO/sub 2/ production from pairs of /sup 14/C-pyruvate, and /sup 14/C-succinate radioisotopes (CO/sub 2/ ratios) indicate the probability of TCA cycle intermediate efflux to generate compounds other than CO/sub 2/. With (2,3-/sup 14/C)succinate as tracer, the ratio of /sup 14/C in carbon 4 + 5 versus carbon 2 + 3 of citrate, the citrate labelling ratio, equals the probability of TCA intermediate flux to the acetyl CoA-derived portion of citrate versus flux to the oxaloacetate-derived portion. The principal metabolic substrates for the jejunal epithelium are glucose and glutamine. CO/sub 2/ ratios indicate that glutamine uptake and metabolism is partially Na/sup +/-independent, and is saturable, with a half-maximal rate at physiological plasma glutamine concentrations. Glucose metabolism in the jejunal epithelium proceeds almost entirely via the Embden-Meyerhof pathway. Conversion of substrates to multi-carbon products in this tissue allows partial conservation of reduced carbon for further utilization in other tissues. In summary, metabolic modeling based on /sup 14/C labelling ratios is a potentially valuable technique for analysis of metabolic flux patterns in cell preparations.

  5. Microvascular Reconstruction of Free Jejunal Graft in Larynx-preserving Esophagectomy for Cervical Esophageal Carcinoma

    PubMed Central

    Natori, Yuhei; Komoto, Masakazu; Matsumura, Takashi; Horiguchi, Masatoshi; Yoshizawa, Hidekazu; Iwanuma, Yoshimi; Tsurumaru, Masahioko; Kajiyama, Yoshiaki; Mizuno, Hiroshi

    2016-01-01

    Background: Losing the ability to speak severely affects the quality of life, and patients who have undergone laryngectomy tend to become depressed, which may lead to social withdrawal. Recently, with advancements in chemoradiotherapy and with alternative perspectives on postoperative quality of life, larynx preservation has been pursued; however, the selection of candidates and the optimal reconstructive procedure remain controversial. In this study, we retrospectively reviewed our experience with free jejunal graft for larynx-preserving cervical esophagectomy (LPCE), focusing on microvascular reconstruction. Methods: Seven patients underwent LPCE for cervical esophageal carcinoma, and defects were reconstructed by free jejunal transfer subsequently. We collected preoperative and postoperative data of the patients and assessed the importance of the procedure. Results: We mostly used the transverse cervical artery as the recipient, and a longer operative time was required, particularly for the regrowth cases. The operative field for microvascular anastomosis was more limited and deeper than those in the laryngectomy cases. Two graft necrosis cases were confirmed at postoperative day 9 or 15, and vessels contralateral from the graft were chosen as recipients in both patients. Conclusions: Microvascular reconstruction for free jejunal graft in LPCE differed in several ways from the procedure combined with laryngectomy. Compression from the tracheal cartilage to the pedicle was suspected as the reason of the necrosis clinically and pathologically. Therefore, we should select recipient vessels from the ipsilateral side of the graft, and careful and extended monitoring of the flap should be considered to make this procedure successful. PMID:27257562

  6. Ileal and jejunal Peyer’s patches in buffalo calves: Histomorphological comparison

    PubMed Central

    Kapoor, Kritima; Singh, Opinder

    2015-01-01

    Aim: The present study was aimed to elucidate the histomorphology of ileal and jejunal Peyer’s patches in the small intestine of buffalo calves and their structural comparison. Materials and Methods: The study was conducted on neonatal (n=10) and pre-pubertal (n=10) buffalo calves. The age of the postnatal buffalo calves was estimated by their temporary and permanent dentition. Results: The study revealed that several layers of oval to elongate elliptical lymphoid follicles were observed in submucosa on the anti-mesenteric side in the ileum of early neonatal calves. However, the follicles at this age, in jejunum were of all shapes present within one layer. The interfollicular space was occupied by the interfollicular tissue, which was diffuse and wider around jejunal lymphoid follicles as compared to ileal lymphoid follicles. However, toward the pubertal stage, the number of layers of lymphoid follicles was reduced in ileum due to involution while it remained similar in number in jejunum at this stage. Conclusion: The ileal Peyer’s patches were found to have started involution more or less around reaching puberty, whereas the jejunal Peyer’s patches appear to be functional throughout the lifespan of the animal. PMID:27047029

  7. Did clockwise rotation of Antarctica cause the break-up of Gondwanaland? An investigation in the 'deep-keeled cratons' frame for global dynamics

    NASA Astrophysics Data System (ADS)

    Osmaston, M. F.

    2012-04-01

    Introduction. The 'deep-keeled cratons' frame for global dynamics is the result of seeking Earth-behaviour answers to the following outside-the-box proposition:- "If cratons have tectospheric keels that reach or approach the 660 km discontinuity, AND the 660 level is an effective barrier to mantle circulation, then obviously (i) when two cratons separate, the upper mantle to put under the nascent ocean must arrive by a circuitous route and, conversely, (ii) if they approach one another, the mantle volume that was in between them must get extruded sideways." Surprisingly it has turned out [1 - 4] that Earth dynamical behaviour for at least the past 150 Ma provides persuasive affirmation of both these expectations and that there is a rational petrological explanation for the otherwise-unexpected immobility of subcratonic material to such depths [5 - 7]. Clockwise rotation of Antarctica? This contribution greatly amplifies my original plate dynamical arguments for suggesting [8] that such rotation is ongoing. Convection is unsuited to causing rotation about a pole within the plate so, as noted then, a gearwheel-like linkage to Africa at the SWIR would provide its clearly CCW (Biscay-Caucasus) relationship to the Mediterranean belt for the past 100 Ma, also seen in its separation from South America. Gearwheel-like linkage of motion requires the presence of some kind of E-W restraint further north. In that case it was the N Africa/Arabia involvement in the Alpide belt, but the earlier opening of the central Atlantic by the eastward motion of Africa, suggests its rigid Gondwanan attachment to Antarctica rotation at that time, with little constraint in the north. Further east, the seafloor data show that Australia-Antarctica separation involved no such opposite rotational linkage, so, with no E-W mechanical constraint in the north by Indonesia, they must have rotated together, as is recorded by Australia's eastward motion to generate the Mesozoic seafloor at its western

  8. The use of jejunal transplants to treat a genetic enzyme deficiency.

    PubMed Central

    Jaffe, B M; Burgos, A A; Martinez-Noack, M

    1996-01-01

    INTRODUCTION: The Gunn rat is an excellent animal model of Crigler-Najjar syndrome, type 1. The liver and small intestine synthesize no functional bilirubin uridine diphosphoglucuronosyl transferase and, consequently, the animals cannot conjugate bilirubin. In prior studies, the authors have shown that 15- to 20-cm jejunal transplants from normal Wistar rats lowered but did not normalize serum bilirubin levels. Phenobarbital has been used to increase enzyme conjugation of bilirubin. HYPOTHESIS: Phenobarbital treatment of Gunn recipients of jejunal transplants from Wistar rats normalizes serum bilirubin levels. METHODS: Forty-three Gunn recipients of jejunal transplants from Wistar rats were divided into four groups: 1) heterotopically placed grafts (Thiry-Vella loops), saline-treated, n = 14; 2) heterotopically placed grafts, phenobarbital-treated (80 mg/kg/day), n = 17; 3) orthotopically placed (in intestinal continuity) grafts, saline-treated, n = 5; and 4) orthotopically placed grafts, phenobarbital-treated, n = 7. Serum was collected before operation and weekly for 8 weeks for measurement of serum total, indirect, and direct bilirubin levels. Animals received cyclosporine, 5 micrograms/kg, daily intramuscularly. RESULTS: Phenobarbital significantly augmented the bilirubin-lowering effect of heterotopic jejunal transplants (group 2). Mean total serum bilirubin fell from 9.14 +/- 0.01 to a nadir of 1.63 +/- 0.11 mg/dL at 6 weeks, after which time, levels began to rise toward baseline (as noted previously). Serum indirect bilirubin levels behaved in a similar fashion. Phenobarbital treatment "normalized" serum bilirubin levels in recipients of orthotopic Wistar jejunal grafts (group 4). Mean total serum bilirubin plummeted from 8.41 +/- 0.20 to 0.76 +/- 0.15 mg/dL at 1 week, and levels remained within the normal range for the entire 8-week study period. Identical changes were observed for serum indirect bilirubin levels. CONCLUSIONS: The combination of

  9. Individual and combined cytotoxic effects of Fusarium toxins (deoxynivalenol, nivalenol, zearalenone and fumonisins B1) on swine jejunal epithelial cells.

    PubMed

    Wan, Lam Yim Murphy; Turner, Paul C; El-Nezami, Hani

    2013-07-01

    Fusarium mycotoxins occur worldwide in foods such as cereals and animal forages, leading to acute and chronic exposures in human and animals. Intestinal epithelial cells (IECs) are an important first target site for these dietary toxins. This study investigated the cytotoxicity of four common Fusarium mycotoxins, deoxynivalenol (DON), nivalenol (NIV), zearalenone (ZEA) and fumonisin B1 (FB1) on a normal porcine jejunal epithelial cell line, IPEC-J2. A dose response relationship between individual mycotoxins and cell viability (MTT assay) was initially investigated, and subsequently cytotoxic and non-cytotoxic concentrations were selected to investigate combinations of two, three and all four of the mycotoxins. For individual mycotoxins, a dose response was observed with cell viability, such that the potency ranking was NIV>DON>ZEA>FB1. At cytotoxic doses of individual mycotoxins, all mixtures gave reduced cell viability compared to control. At noncytotoxic concentrations of individual mycotoxins, all mixtures were cytotoxic with DON-NIV, DON-ZEA, DON-NIV-FB1, DON-ZEA-FB1, NIV-ZEA-FB1 and all four mixed causing the greatest loss of cell viability. The latter observation in particular raises concerns over safety margins based on single toxin species, and suggests that the effects of multiple complex mixtures need to be better understood to assess health risks. PMID:23562706

  10. Effects of docosahexaenoic acid and sardine oil diets on the ultrastructure of jejunal absorptive cells in adult mice.

    PubMed

    Tamura, M; Suzuki, H

    1996-01-01

    The influence of docosahexaenoic acid (DHA) and sardine oil diets on the ultrastructure of jejunal absorptive cells was studied. Adult male Crj:CD-1 (ICR) mice were fed a fat-free semisynthetic diet supplemented with 5% (by weight) purified DHA ethyl ester, refined sardine oil, or palm oil. The mice received the DHA or palm oil diets for 7 days (groups 1 and 2) and the refined sardine oil or palm oil diets for 30 days (groups 3 and 4). There were significant ultrastructural changes in the jejunal absorptive cells between the mice fed on the palm oil diet and those receiving the DHA and sardine oil diets. The endoplasmic reticulum and Golgi apparatus of some jejunal absorptive cells in the mice fed on the palm oil diet for 7 and 30 days developed vacuolation on the upper site of the nucleus. In contrast, many granules, which appeared to be lipid droplets, were observed in the endoplasmic reticulum and Golgi apparatus of the jejunal absorptive cells in the DHA and sardine oil diet groups. These results suggest that ultrastructural differences in the jejunal absorptive cells between mice in the omega-3 fatty acid and palm oil diet groups may be associated with the changes in lipid metabolism.

  11. Absence of a cAMP-mediated antiabsorptive effect in an undifferentiated jejunal epithelium.

    PubMed

    MacLeod, R J; Hamilton, J R

    1987-06-01

    In the relatively undifferentiated jejunal mucosa occurring in piglet viral enteritis, we measured the response of transepithelial Na+ and Cl- fluxes in vitro to raised intracellular adenosine 3',5'-cyclic monophosphate (cAMP) levels. At the acute 40-h stage of transmissible gastroenteritis (TGE), luminal membrane markers, sucrase and lactase, and a basolateral jejunal epithelial membrane marker Na+-K+-ATPase, were significantly decreased in activity, while a proliferative marker, thymidine kinase, was significantly enriched; these enzyme characteristics are typical of enterocytes isolated from crypts of other species. As expected, control piglet jejunum in short-circuited Ussing chambers after theophylline (10 mM) developed significant net secretory Na and Cl fluxes primarily due to significant antiabsorptive effects (delta JNa m----s = 3.48 +/- 0.52, delta JCl m----s = 2.59 +/- 0.28). Furosemide (10(-4) M), an inhibitor of electroneutral NaCl cotransport, produced antiabsorptive effects (delta JNa m----s = 2.53 +/- 0.31, delta JCl m----s = 2.58 +/- 0.28) in control jejunum that were not significantly different from those seen in response to theophylline. TGE jejunum, however, responded to theophylline not by an antiabsorptive effect but by significant electrogenic Cl- secretion (delta JCl s----m = 1.59 +/- 0.48); furosemide had no effect on ion fluxes in TGE tissue. Control and TGE jejunal mucosal homogenates did not differ in their basal or theophylline-stimulated levels of cAMP. We conclude that the relatively undifferentiated small intestine occurring in acute TGE does not generate either a cAMP-mediated antiabsorptive effect or a furosemide-mediated antiabsorptive effect.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Cystic jejunal duplication with Heinrich’s type I ectopic pancreas, incidentally discovered in a patient with pancreatic tail neoplasm

    PubMed Central

    Gurzu, Simona; Bara Jr, Tivadar; Bara, Tivadar; Fetyko, Annamaria; Jung, Ioan

    2016-01-01

    The aim of this study was to present a case of enteric duplication cyst and criteria for a proper differential diagnosis. A 51-year-old male was hospitalized for pancreatic tail neoplasm and distal pancreatectomy with splenectomy was performed. During surgery, a jejunal cystic lesion was incidentally detected and jejunectomy was performed. Microscopically, the cyst was observed to be covered by Keratin 7/Keratin 20 positive intestinal type epithelium and the muscularis layer was shared by the cyst and adjacent jejunum, without a cleavage plane between the cyst wall and jejunal muscularis propria. In the deep muscularis propria, a Heinrich’s type I ectopic pancreas was also noted. In the pancreatic tail, a low grade intraepithelial lesion (panIN-1a) was diagnosed. This case highlights the necessity for a correct differential diagnosis of such rare lesions. Roughly 30 cases of jejunal duplication cysts have been reported to date in the PubMed database. PMID:27672644

  13. The uptake of vitamin B12 by the sediment of jejunal contents in patients with the blind-loop syndrome.

    PubMed

    Schjönsby, H; Hofstad, T

    1975-01-01

    Following preincubation of intrinsic factor- (IF-) bound 57CoB12 with the jejunal sediments of 6 patients with the blind-loop syndrome, the mean uptake by the sediments of IF-57CoB12 (28.1 percent plus or minus 4.2 percent S,E.M.) was significantly higher than the mean uptake by jejunal sediments from 5 control patients (5.8 per cent plus or minus 3.5 percent) (p smaller than 0.01). The uptake by the sediments significantly decreased when the incubations were carried out in the presence of lincomycin and neomycin. The jejunal sediments from the patients with the blind-loop syndrome inhibited the uptake of IF-57CoB12 by perfused rat intestinal segments (p smaller than 0.01), whereas the sediments from the control patients had no such inhibitory effect (p smaller than 0.5).

  14. Cystic jejunal duplication with Heinrich's type I ectopic pancreas, incidentally discovered in a patient with pancreatic tail neoplasm.

    PubMed

    Gurzu, Simona; Bara, Tivadar; Bara, Tivadar; Fetyko, Annamaria; Jung, Ioan

    2016-09-16

    The aim of this study was to present a case of enteric duplication cyst and criteria for a proper differential diagnosis. A 51-year-old male was hospitalized for pancreatic tail neoplasm and distal pancreatectomy with splenectomy was performed. During surgery, a jejunal cystic lesion was incidentally detected and jejunectomy was performed. Microscopically, the cyst was observed to be covered by Keratin 7/Keratin 20 positive intestinal type epithelium and the muscularis layer was shared by the cyst and adjacent jejunum, without a cleavage plane between the cyst wall and jejunal muscularis propria. In the deep muscularis propria, a Heinrich's type I ectopic pancreas was also noted. In the pancreatic tail, a low grade intraepithelial lesion (panIN-1a) was diagnosed. This case highlights the necessity for a correct differential diagnosis of such rare lesions. Roughly 30 cases of jejunal duplication cysts have been reported to date in the PubMed database. PMID:27672644

  15. Jejunal pseudodiverticulosis in a swamp wallaby (Wallabia bicolor).

    PubMed

    Haist, V; von Dörnberg, K; Jacobsen, B

    2012-11-01

    Necropsy examination of an 8-year-old female swamp wallaby (Wallabia bicolor) from a zoological garden revealed four intestinal diverticular outpouchings at the mesenteric border of the jejunum, which were partly ruptured causing a fatal peritonitis. Microscopically, affected small intestinal segments were characterized by an abrupt gap in the muscular layer with subsequent herniation of respective mucosal and submucosal layers, interpreted as acquired pseudodiverticula. Multifocal perforations of these diverticula were associated with prominent fibrinosuppurative serositis with leakage of ingesta. In addition, there was intestinal nematodal endoparasitism with accompanying neutrophilic to eosinophilic enteritis. Small intestinal pseudodiverticula resembling human colonic diverticulosis are rare in animals and can lead to fatal peritonitis by faecal impaction, subsequent transmural inflammation and eventual perforation. PMID:22717131

  16. [Surgical therapy of segmental jejunal, primary intestinal lymphangiectasia].

    PubMed

    Kneist, W; Drescher, D G; Hansen, T; Kreitner, K F; Lang, H

    2013-06-01

    Primary intestinal lymphangiectasia (PIL) is a protein-losing, exsudative gastroenteropathy causing lymphatic obstruction. Diagnosis depends on clinical examination and histological findings. Conservative treatment modalities include a low-fat diet and enteral nutritional therapy in order to reduce enteric protein loss and to improve fat metabolism. Other treatment options consist of administration of antiplasmin or octreotide to lower lymph flow and secretion. We report on a 58-year-old patient who underwent exploratory laparotomy due to a worsening physical status, recurrent chylaskos and leg oedema under conservative dietary therapy. Intraoperative findings showed a typical PIL of the jejunum about 20 cm distal to the Treitz's ligament. Histological examinations confirmed this diagnosis. One year after segmental small bowel resection (105 cm) with end-to-end anastomosis the patient is healthy, free of symptoms, has gained weight and his serum protein level has increased. Intraabdominal ascites and leg oedema have not reoccurred since. PMID:23229460

  17. Percutaneous Endoscopic Gastrostomy with Jejunal Extension for an Encapsulating Peritoneal Sclerosis Refractory to Surgical Enterolysis.

    PubMed

    Banshodani, Masataka; Kawanishi, Hideki; Moriishi, Misaki; Shintaku, Sadanori; Hashimoto, Shinji; Tsuchiya, Shinichiro

    Surgical enterolysis is the final option for patients with encapsulating peritoneal sclerosis (EPS). However, EPS is sometimes refractory to surgical enterolysis. This is the first report of successful use of percutaneous endoscopic gastrostomy with jejunal extension (PEG-J) in a patient with EPS that was refractory to surgical enterolysis. We propose that sustained drainage of digestive juices by PEG-J, along with central venous nourishment at home, can be a treatment option for patients with EPS that cannot be treated with radical measures. PMID:27659928

  18. Fluoroscopy-guided jejunal extension tube placement through existing gastrostomy tubes: analysis of 391 procedures

    PubMed Central

    Uflacker, Andre; Qiao, Yujie; Easley, Genevieve; Patrie, James; Lambert, Drew; de Lange, Eduard E.

    2015-01-01

    PURPOSE We aimed to evaluate the safety and efficacy of fluoroscopically placed jejunal extension tubes (J-arm) in patients with existing gastrostomy tubes. METHODS We conducted a retrospective review of 391 J-arm placements performed in 174 patients. Indications for jejunal nutrition were aspiration risk (35%), pancreatitis (17%), gastroparesis (13%), gastric outlet obstruction (12%), and other (23%). Technical success, complications, malfunctions, and patency were assessed. Percutaneous gastrostomy (PEG) tube location, J-arm course, and fluoroscopy time were correlated with success/failure. Failure was defined as inability to exit the stomach. Procedure-related complications were defined as adverse events related to tube placement occurring within seven days. Tube malfunctions and aspiration events were recorded and assessed. RESULTS Technical success was achieved in 91.9% (95% CI, 86.7%–95.2%) of new tubes versus 94.2% (95% CI, 86.7%–95.2%) of replacements (P = 0.373). Periprocedural complications occurred in three patients (0.8%). Malfunctions occurred in 197 patients (50%). Median tube patency was 103 days (95% CI, 71–134 days). No association was found between successful J-arm placement and gastric PEG tube position (P = 0.677), indication for jejunal nutrition (P = 0.349), J-arm trajectory in the stomach and incidence of malfunction (P = 0.365), risk of tube migration and PEG tube position (P = 0.173), or J-arm length (P = 0.987). A fluoroscopy time of 21.3 min was identified as a threshold for failure. Malfunctions occurred more often in tubes replaced after 90 days than in tubes replaced before 90 days (P < 0.001). A total of 42 aspiration events occurred (OR 6.4, P < 0.001, compared with nonmalfunctioning tubes). CONCLUSION Fluoroscopy-guided J-arm placement is safe for patients requiring jejunal nutrition. Tubes indwelling for longer than 90 days have higher rates of malfunction and aspiration. PMID:26380895

  19. Duodenal and jejunal atresia with agenesis of the dorsal mesentery: "apple peel" small bowel.

    PubMed

    Zivković, S M; Milosević, V R

    1979-05-01

    Two newborn infants with duodenal and jejunal atresia and agenesis of the dorsal mesentery represent our surgical experience with "apple peel" small bowel or "christmas tree" demormity. The first patient had the typical appearance of this condition. The postoperative course was complicated by hyperbilirubinemia, septicemia, and disseminated intravascular coagulation. The infant is in satisfactory condition 1.5 years after operation. The second patient had agenesis of the dorsal mesentery without spiraling of the bowel around its vascular stalk. The child died after 1 month, with complete absence of extrahepatic bile ducts as seen at a second laparotomy. Neither child had been subjected to gastrostomy.

  20. Mouldy feed, mycotoxins and Shiga toxin - producing Escherichia coli colonization associated with Jejunal Hemorrhage Syndrome in beef cattle

    PubMed Central

    2011-01-01

    Background Both O157 and non-O157 Shiga toxin - producing Escherichia coli (STECs) cause serious human disease outbreaks through the consumption of contaminated foods. Cattle are considered the main reservoir but it is unclear how STECs affect mature animals. Neonatal calves are the susceptible age class for STEC infections causing severe enteritis. In an earlier study, we determined that mycotoxins and STECs were part of the disease complex for dairy cattle with Jejunal Hemorrhage Syndrome (JHS). For STECs to play a role in the development of JHS, we hypothesized that STEC colonization should also be evident in beef cattle with JHS. Aggressive medical and surgical therapies are effective for JHS, but rely on early recognition of clinical signs for optimal outcomes suggesting that novel approaches must be developed for managing this disease. The main objective of this study was to confirm that mouldy feeds, mycotoxins and STEC colonization were associated with the development of JHS in beef cattle. Results Beef cattle developed JHS after consuming feed containing several types of mycotoxigenic fungi including Fusarium poae, F. verticillioides, F. sporotrichioides, Penicillium roqueforti and Aspergillus fumigatus. Mixtures of STECs colonized the mucosa in the hemorrhaged tissues of the cattle and no other pathogen was identified. The STECs expressed Stx1 and Stx2, but more significantly, Stxs were also present in the blood collected from the lumen of the hemorrhaged jejunum. Feed extracts containing mycotoxins were toxic to enterocytes and 0.1% of a prebiotic, Celmanax Trademark, removed the cytotoxicity in vitro. The inclusion of a prebiotic in the care program for symptomatic beef calves was associated with 69% recovery. Conclusions The current study confirmed that STECs and mycotoxins are part of the disease complex for JHS in beef cattle. Mycotoxigenic fungi are only relevant in that they produce the mycotoxins deposited in the feed. A prebiotic, Celmanax

  1. Experiment K-7-17: Effects of Spaceflight on the Proliferation of Jejunal Mucosal Cells

    NASA Technical Reports Server (NTRS)

    Phillips, R. W.; Moeller, C. L.; Sawyer, H. R.; Smirnov, K. L.

    1994-01-01

    The purpose of this project was to test the hypothesis that the generalized, whole body decrease in synthetic activity due to microgravity conditions encountered during spaceflight would be demonstrable in cells and tissues characterized by a rapid rate of turnover. Jejunal mucosal cells were chosen as a model since these cells are among the most rapidly proliferating in the body. Accordingly, the percentage of mitotic cells present in the crypts of Lieberkuhn in each of 5 rats flown on the COSMOS 2044 mission were compared to the percentage of mitotic cells present in the crypts in rats included in each of 3 ground control groups (i.e., vivarium, synchronous and caudal-elevated). No significant difference (p greater than .05) was detected in mitotic indices between the flight and vivarium group. Although the ability of jejunal mucosal cells to divide by mitosis was not impaired in flight group, there was, however, a reduction in the length of villi and depth of crypts. The concommitant reduction in villus length and crypth depth in the flight group probably reflects changes in connective tissue components within the core of villi.

  2. Ectopic Jejunal Variceal Rupture in a Liver Transplant Recipient Successfully Treated With Percutaneous Transhepatic Coil Embolization

    PubMed Central

    Abe, Satoru; Akamatsu, Nobuhisa; Hoshikawa, Mayumi; Shirata, Chikara; Sakamoto, Yoshihiro; Hasegawa, Kiyoshi; Kokudo, Norihiro

    2015-01-01

    Abstract Here we present the rupture of ectopic jejunal varices developing in a liver transplant recipient without portal hypertension, which was successfully treated with percutaneous transhepatic coil embolization. A 48-year-old man with massive melena was admitted to our department. He had undergone liver transplantation for hepatitis B virus-related liver cirrhosis 8 months before, and his postoperative course was satisfactory except for an acute cellular rejection. No evidence of bleeding was detected by upper endoscopy or colonoscopy, but dynamic multidetector computed tomography of the whole abdomen revealed an intestinal varix protruding into the lumen of the jejunum with suspected extravasation. There was no evidence of portal venous stenosis or thrombosis. Immediately upon diagnosis of the ruptured ectopic jejunal varix, percutaneous transhepatic coil embolization was performed, achieving complete hemostasis. The portal venous pressure measured during the procedure was within normal limits. He was discharged from the hospital 11 days after embolization and remained in stable condition without re-bleeding 6 months after discharge. This is the first report of an ectopic intestinal variceal rupture in an uneventful liver transplant recipient that was successfully treated with interventional percutaneous transhepatic coil embolization. Clinicians encountering liver transplant recipients with melena should be aware of the possibility of late-onset rupture of ectopic varices, even in those having an uneventful post-transplant course without portal hypertension. PMID:26632745

  3. A case of lymphocytic-plasmacytic jejunitis diagnosed by double-balloon enteroscopy in a dog.

    PubMed

    Ayala, Ignacio; Latorre, Rafael; Soria, Federico; Carballo, Fernando; Lopez-Albors, Octavio; Buendia, Antonio J; Perez-Cuadrado, Enrique

    2011-01-01

    A 3 yr old male English setter dog was presented for evaluation of a 6-wk history of intermittent diarrhea. After standard gastroduodenoscopy and colonoscopy showed normal mucosa, double-balloon endoscopy (DBE) was used via both oral and anal approaches. Gross changes consistent with inflammation in the jejunum were seen, and biopsy specimens were obtained. Histologic analysis confirmed a diagnosis of lymphocytic-plasmacytic jejunitis. Clinical remission of the disease occurred after 3 mo of therapy with prednisone, metronidazole, and a novel protein diet. Use of DBE has not been previously reported in dogs with inflammatory bowel disease, and isolated lymphocytic-plasmacytic jejunitis has not been described. The described cases of intestinal inflammatory disease diagnosed by conventional endoscopy were related to pathologic changes in the duodenum, ileum or colon, but not the jejunum. The main advantage of the DBE technique allowed examination of portions of the small intestine (jejunum) that were not commonly accessible by standard endoscopic techniques, and permitted a minimally invasive collection of biopsy samples compared with surgical biopsy. This case highlights the need to consider using DBE in animals with gastrointestinal disorders, whose symptoms are not readily explained by routine tests, conventional endoscopy, and dietary or therapeutic trials.

  4. Effect of duodenal-jejunal bypass surgery on glycemic control in type 2 diabetes: a randomized controlled trial

    PubMed Central

    Petry, Tarissa Z.; Fabbrini, Elisa; Otoch, Jose P.; Carmona, Murilo A.; Caravatto, Pedro P.; Salles, João E.; Sarian, Thais; Correa, Jose L.; Schiavon, Carlos A.; Patterson, Bruce W.; Cohen, Ricardo; Klein, Samuel

    2015-01-01

    Objective To determine whether upper gastrointestinal tract (UGI) bypass itself has beneficial effects on the factors involved in regulating glucose homeostasis in patients with type 2 diabetes (T2D). Methods A 12-month randomized controlled trial was conducted in 17 overweight/obese subjects with T2D, who received standard medical care (SC, n=7, BMI=31.7±3.5 kg/m2) or duodenal-jejunal bypass surgery with minimal gastric resection (DJBm) (n=10; BMI=29.7±1.9 kg/m2). A 5-h modified oral glucose tolerance test (OGTT) was performed at baseline and at 1, 6 and 12 months after surgery or starting SC. Results Body weight decreased progressively after DJBm (7.9±4.1%, 9.6±4.2%, and 10.2±4.3% at 1, 6, and 12 months, respectively), but remained stable in the SC group (P<0.001). DJBm, but not SC, improved: 1) oral glucose tolerance (decreased 2-hr glucose concentration, P=0.039), 2) insulin sensitivity (decreased Homeostatic Model Assessment of Insulin Resistance, P=0.013), 3) early insulin response to a glucose load (increased insulinogenic index, P=0.022), and 4) overall glycemic control (reduction in HbA1c with less diabetes medications). Conclusions DJBm causes moderate weight loss and improves metabolic function in T2D. However, our study cannot separate the benefits of moderate weight loss from the potential therapeutic effect of UGI tract bypass itself on the observed metabolic improvements. PMID:26414562

  5. Four-photon spectroscopy of rotational transitions in liquid: recording of changes in the chemical composition of water caused by cavitation

    SciTech Connect

    Bunkin, Aleksei F; Pershin, S M

    2010-05-26

    It is shown for the first time by the method of four-photon coherent scattering by rotational molecular resonances that the cavitation action on water changes its chemical composition, resulting in the formation of hydrogen peroxide. It is found that the concentration of hydrogen peroxide during cavitation grows by several times and depends on the cavitation process technology.

  6. Dietary Leucine Supplementation Improves the Mucin Production in the Jejunal Mucosa of the Weaned Pigs Challenged by Porcine Rotavirus

    PubMed Central

    Mao, Xiangbing; Liu, Minghui; Tang, Jun; Chen, Hao; Chen, Daiwen; Yu, Bing; He, Jun; Yu, Jie; Zheng, Ping

    2015-01-01

    The present study was mainly conducted to determine whether dietary leucine supplementation could attenuate the decrease of the mucin production in the jejunal mucosa of weaned pigs infected by porcine rotavirus (PRV). A total of 24 crossbred barrows weaned at 21 d of age were assigned randomly to 1 of 2 diets supplemented with 1.00% L-leucine or 0.68% L-alanine (isonitrogenous control) for 17 d. On day 11, all pigs were orally infused PRV or the sterile essential medium. During the first 10 d of trial, dietary leucine supplementation could improve the feed efficiency (P = 0.09). The ADG and feed efficiency were impaired by PRV infusion (P<0.05). PRV infusion also increased mean cumulative score of diarrhea, serum rotavirus antibody concentration and crypt depth of the jejunal mucosa (P<0.05), and decreased villus height: crypt depth (P = 0.07), goblet cell numbers (P<0.05), mucin 1 and 2 concentrations (P<0.05) and phosphorylated mTOR level (P<0.05) of the jejunal mucosa in weaned pigs. Dietary leucine supplementation could attenuate the effects of PRV infusion on feed efficiency (P = 0.09) and mean cumulative score of diarrhea (P = 0.09), and improve the effects of PRV infusion on villus height: crypt depth (P = 0.06), goblet cell numbers (P<0.05), mucin 1 (P = 0.08) and 2 (P = 0.07) concentrations and phosphorylated mTOR level (P = 0.08) of the jejunal mucosa in weaned pigs. These results suggest that dietary 1% leucine supplementation alleviated the decrease of mucin production and goblet cell numbers in the jejunal mucosa of weaned pigs challenged by PRV possibly via activation of the mTOR signaling. PMID:26336074

  7. Rotating Vesta

    NASA Video Gallery

    Astronomers combined 146 exposures taken by NASA's Hubble SpaceTelescope to make this 73-frame movie of the asteroid Vesta's rotation.Vesta completes a rotation every 5.34 hours.› Asteroid and...

  8. Rotational moulding.

    PubMed

    Crawford, R J; Kearns, M P

    2003-10-01

    Rotational moulding promises designers attractive economics and a low-pressure process. The benefits of rotational moulding are compared here with other manufacturing methods such as injection and blow moulding. PMID:14603714

  9. Challenging diagnosis of a jejunal adenocarcinoma with ovarian metastasis: report of an unusual case

    PubMed Central

    Huang, Yang Yang; Pratt, Jeremy John; Dabner, Marcus; Tjhin, William

    2013-01-01

    We report the first documented case of ovarian metastasis from a jejunal primary adenocarcinoma in an Australian patient. The presentation was unusual, initially a suspicious abdominal nodule in the epigastric area, which turned out to be an adenocarcinoma of possible intestinal origin. Gastroscopy and colonoscopy were performed with no suspicious lesion identified. Abdominal and pelvic ultrasound imaging showed a complex pelvic mass suspicious of ovarian cancer. Laparoscopy was performed to exclude possibility of ovarian cancer and small bowel cancer. The ovarian mass showed similar features from the epigastric nodule, again suggestive of intestinal primary. Definitive diagnosis was obtained when the patient represented 2 months later with malignant bowel obstruction requiring palliative resection of the proximal jejunum. This case demonstrates the difficulty in diagnosing ovarian metastasis from a small bowel primary, which has the potential to mimic an ovarian primary tumour clinically, and a large bowel or ovarian primary pathologically. PMID:23580681

  10. First jejunal artery, an alternative graft for right hepatic artery reconstruction.

    PubMed

    Aryal, Bibek; Komokata, Teruo; Kadono, Jun; Motodaka, Hiroyuki; Ueno, Tetsuya; Furoi, Akira; Imoto, Yutaka

    2015-04-01

    Common bile duct cancer invading right hepatic artery is sometimes diagnosed intraoperatively. Excision and safe reconstruction of the artery with suitable graft is essential. Arterial reconstruction with autologous saphenous vein graft is the preferred method practiced routinely. However the right hepatic artery reconstruction has also been carried out with several other vessels like gastroduodenal artery, right gastroepiploic artery or the splenic artery. We report a case of 63-year-old man presenting with history of progressive jaundice, pruritus and impaired appetite. Following various imaging modalities including computed tomography, endoscopic retrograde cholangiopancreatography, magnetic resonance cholangiopancreatography, intraductal ultrasound extrahepatic bile duct cancer was diagnosed; however, none of those detected vessel invasion. Intraoperatively, right hepatic artery invasion was revealed. Right hepatic artery was resected and reconstructed with a graft harvested from the first jejunal artery (JA). Postoperative outcome was satisfactory with a long-term graft patency. First JA can be a reliable graft option for right hepatic artery reconstruction.

  11. Mechanism of bile acid-regulated glucose and lipid metabolism in duodenal-jejunal bypass

    PubMed Central

    Chai, Jie; Zou, Lei; Li, Xirui; Han, Dali; Wang, Shan; Hu, Sanyuan; Guan, Jie

    2015-01-01

    Bile acid plays an important role in regulating blood glucose, lipid and energy metabolism. The present study was implemented to determine the effect of duodenal-jejunal bypass (DJB) on FXR, TGR-5expression in terminal ileum and its bile acid-related mechanism on glucose and lipid metabolism. Immunohistochemistry was used to detect relative gene or protein expression in liver and intestine. Firstly, we found that expression of FXR in liver and terminal ileum of DJB group was significantly higher than that in S-DJB group (P<0.05). In addition, DJB dramatically increased the activation of TGR-5 in the liver of rats. Furthermore, PEPCK, G6Pase, FBPase 1 and GLP-1 were up-regulated by DJB. In conclusion, these results showed that bile acid ameliorated glucose and lipid metabolism through bile acid-FXR and bile acid- TGR-5 signaling pathway. PMID:26884847

  12. Examination of the low proliferative capacity of human jejunal intraepithelial lymphocytes.

    PubMed Central

    Ebert, E C; Roberts, A I; Brolin, R E; Raska, K

    1986-01-01

    The proliferation of human jejunal intraepithelial lymphocytes (IEL) was examined to determine how it differed from that of peripheral blood (PB) T lymphocytes. The IEL were mainly T lymphocytes of the cytotoxic-suppressor (T8+) phenotype. They demonstrated lower proliferative responses to various stimuli (2,501 +/- 565 ct/min with phytohaemagglutinin; PHA) compared to unseparated PB T lymphocytes (73,678 +/- 2,495) or the T8+ subset (68,939 +/- 10,053 ct/min) (P less than 0.001). This low proliferative response was also a characteristic of the T8+ T lymphocytes in the lamina propria (4,606 +/- 1,226 ct/min) but not the T4+ subset (43,447 +/- 10,188 ct/min) (P less than 0.05). These findings were not due to isolation techniques or to differences in kinetics. Mixing experiments revealed that the IEL did not contain cells which suppressed proliferation. In addition, the IEL could be stimulated by mitogens, as they produced the same amount of interleukin 2 (IL-2) and IL-2 receptors as did PB T lymphocytes. Although the lectin-induced proliferative response of IEL was unaltered by the addition of autologous macrophages and minimally increased by IL-2, it was markedly enhanced by the addition of sheep red blood cells (SRBC). The enhancing effect of SRBC was not due to T cell recognition of xenogenic antigens on the erythrocytes since neither allogeneic non-T lymphocytes nor other xenogenic erythrocytes produced the same effect. Both intact SRBC and membrane fragments from osmotically lysed cells augmented lymphocyte proliferation. Thus, jejunal IEL could be activated by mitogen and proliferated as much as PB T lymphocytes if exposed to a membrane component found on SRBC. PMID:2947761

  13. Protection of mouse jejunal crypt cells by WR-2721 after small doses of radiation.

    PubMed

    Travis, E L; Thames, H D; Tucker, S L; Watkins, T L; Kiss, I

    1986-05-01

    The ability of WR-2721 to protect jejunal crypt cells after single doses and multifractionated doses of radiation was studied. Effective dose survival curves for jejunal crypt cells were constructed over the dose range of 230 to 1600 cGy. WR-2721 was given 30 minutes before each fraction, in a regimen consisting of 200 mg/kg before the first radiation fraction, followed at 3 hr intervals by 100 mg/kg for a total of 12 drug doses for the largest number of fractions. Fractionation protocols were designed with common dose fractions in regimens with different fraction numbers, allowing a test of the hypothesis of equal effect per fraction and an estimate of the initial number of clonogens per crypt in both the drug treated and non-drug treated mice. The hypothesis of equal effect per fraction could not be rejected in either the drug or non-drug treated mice. An average number of 137 clonogens per crypt was estimated for the non-drug treated mice and 81 clonogens per crypt in the drug treated mice; the difference between these two values was not significant. The protection factor decreased with decreasing dose ranging from a high of 1.47 (95% C.L. = 1.44 to 1.50) after a single dose of 2000 cGy to a low of 1.21 (95% C.L. = 1.08 to 1.37) after 200 cGy. Analysis of the data using either the linear quadratic (LQ) or two-component (TC) model of cell survival showed that WR-2721 was not dose-modifying over the dose range tested. Analysis using the LQ model showed that both beta and alpha were modified by WR-2721, by 50% and 20% respectively. These data indicate that protection by WR-2721 can be expected to decrease with dose although there is some protection after clinically relevant doses. PMID:3011713

  14. ASSESSMENT OF THE GASTRO-JEJUNO-DUODENAL TRANSIT AFTER JEJUNAL POUCH INTERPOSITION

    PubMed Central

    da SILVA, Alcino Lázaro; GOMES, Célio Geraldo de Oliveira

    2015-01-01

    Background : The jejunal pouch interposition between the gastric body and the duodenum after the gastrectomy, although not frequent in the surgical practice today, has been successfully employed for the prevention and treatment of the postgastrectomy syndromes. In the latter, it is included the dumping syndrome, which affects 13-58% of the patients who undergo gastrectomy. Aim : Retrospective assessment of the results of this procedure for the prevention of the dumping syndrome. Methods : Fourty patients were selected and treatetd surgically for peptic ulcer, between 1965 and 1970. Of these, 29 underwent vagotomy, antrectomy, gastrojejunalduodenostomy at the lesser curvature level, and the 11 remaining were submitted to vagotomy, antrectomy, gastrojejunal-duodenostomy at the greater curvature level. The gastro-jejuno-duodenal transit was assessed in the immediate or late postoperative with the contrasted study of the esophagus, stomach and duodenum. The clinical evolution was assessed according to the Visick grade. Results : Of the 40 patients, 28 were followed with the contrast evaluation in the late postoperative. Among those who were followed until the first month (n=22), 20 (90%) had slow gastro-jejuno-duodenal transit and in two (10%) the transit was normal. Among those who were followed after the first month (n=16), three (19%) and 13 (81%) had slow and normal gastric emptying, respectively. None had the contrasted exam compatible with the dumping syndrome. Among the 40 patients, 22 underwent postoperative clinical evaluation. Of these, 19 (86,5%) had excellent and good results (Visick 1 and 2, respectively). Conclusions : The jejunal pouch interposition showed to be a very effective surgical procedure for the prevention of the dumping syndrome in gastrectomized patients. PMID:26734789

  15. On the determination of heliographic positions and rotation velocities of sunspots. III - Effects caused by wrong solar image radii and their corrections

    NASA Astrophysics Data System (ADS)

    Balthasar, H.; Lustig, G.; Woehl, H.

    1984-03-01

    The effect of incorrect solar-image radius on the determination of the rotation velocity of sunspots is analyzed by comparing data collected at Sonnenobservatorium Kanzelhoehe with those from Locarno and Greenwich (for May and September, 1982, and for 27 stable recurrent sunspots during 1950-1976, respectively). While the Locarno data are insufficient to draw quantitative conclusions, the Kanzelhoehe/Greenwich comparison reveals a time-independent discrepancy of 0.004 deg/day, corresponding to a velocity difference of less than 1 m/s, from the 'true' values determined from successive passages through the central meridian.

  16. Rotational testing.

    PubMed

    Furman, J M

    2016-01-01

    The natural stimulus for the semicircular canals is rotation of the head, which also might stimulate the otolith organs. Vestibular stimulation usually induces eye movements via the vestibulo-ocular reflex (VOR). The orientation of the subject with respect to the axis of rotation and the orientation of the axis of rotation with respect to gravity together determine which labyrinthine receptors are stimulated for particular motion trajectories. Rotational testing usually includes the measurement of eye movements via a video system but might use a subject's perception of motion. The most common types of rotational testing are whole-body computer-controlled sinusoidal or trapezoidal stimuli during earth-vertical axis rotation (EVAR), which stimulates primarily the horizontal semicircular canals bilaterally. Recently, manual impulsive rotations, known as head impulse testing (HIT), have been developed to assess individual horizontal semicircular canals. Most types of rotational stimuli are not used routinely in the clinical setting but may be used in selected research environments. This chapter will discuss clinically relevant rotational stimuli and several types of rotational testing that are used primarily in research settings. PMID:27638070

  17. Spatial variability of soil total and DTPA-extractable cadmium caused by long-term application of phosphate fertilizers, crop rotation, and soil characteristics.

    PubMed

    Jafarnejadi, A R; Sayyad, Gh; Homaee, M; Davamei, A H

    2013-05-01

    Increasing cadmium (Cd) accumulation in agricultural soils is undesirable due to its hazardous influences on human health. Thus, having more information on spatial variability of Cd and factors effective to increase its content on the cultivated soils is very important. Phosphate fertilizers are main contamination source of cadmium (Cd) in cultivated soils. Also, crop rotation is a critical management practice which can alter soil Cd content. This study was conducted to evaluate the effects of long-term consumption of the phosphate fertilizers, crop rotations, and soil characteristics on spatial variability of two soil Cd species (i.e., total and diethylene triamine pentaacetic acid (DTPA) extractable) in agricultural soils. The study was conducted in wheat farms of Khuzestan Province, Iran. Long-term (27-year period (1980 to 2006)) data including the rate and the type of phosphate fertilizers application, the respective area, and the rotation type of different regions were used. Afterwards, soil Cd content (total or DTPA extractable) and its spatial variability in study area (400,000 ha) were determined by sampling from soils of 255 fields. The results showed that the consumption rate of di-ammonium phosphate fertilizer have been varied enormously in the period study. The application rate of phosphorus fertilizers was very high in some subregions with have extensive agricultural activities (more than 95 kg/ha). The average and maximum contents of total Cd in the study region were obtained as 1.47 and 2.19 mg/kg and DTPA-extractable Cd as 0.084 and 0.35 mg/kg, respectively. The spatial variability of Cd indicated that total and DTPA-extractable Cd contents were over 0.8 and 0.1 mg/kg in 95 and 25 % of samples, respectively. The spherical model enjoys the best fitting and lowest error rate to appraise the Cd content. Comparing the phosphate fertilizer consumption rate with spatial variability of the soil cadmium (both total and DTPA extractable) revealed the high

  18. Quantitative assessment of the mucosal architecture of jejunal biopsy specimens: a comparison between linear measurement, stereology, and computer aided microscopy.

    PubMed Central

    Corazza, G R; Frazzoni, M; Dixon, M F; Gasbarrini, G

    1985-01-01

    Fifty jejunal biopsy specimens obtained from normal subjects and from untreated and treated patients with coeliac disease were assessed blindly by three independent observers, each of them using different morphometric techniques-namely, linear measurement, stereology, and computer aided microscopy. In two of 26 control biopsy specimens linear measurement was not possible because of distortion of villi. Highly significant (p less than 0.001) correlation coefficients were found between the different techniques. With all methods significant differences between controls and patients with coeliac disease and between treated and untreated coeliac patients were found. Only by stereology, however, was there no overlap between results for patients and those for controls. In view of the limitations of linear measurement and the high cost and complexity of computer aided microscopy, we propose that a simple stereological technique using an eyepiece graticule is the method of choice in the quantitative assessment of mucosal architecture in jejunal biopsy specimens. Images PMID:3894431

  19. A Case of Laparoscopic Resection for Carcinoma of the Gastric Remnant following Proximal Gastrectomy Reconstructed with Jejunal Interposition

    PubMed Central

    Iwasaki, Yoshiaki; Yuu, Ken; Oohinata, Ryouki; Amaki, Misato; Kohira, Yoshinori; Natsume, Souichiro; Ishiyama, Satoshi; Takahashi, Keiichi

    2016-01-01

    A 72-year-old Japanese man had a history of proximal gastrectomy for early gastric cancer located in the upper third of the stomach in 2007. Our usual treatment strategy for early gastric cancer in the upper third of the stomach in 2007 was open proximal gastrectomy reconstructing by jejunal interposition with a 10 cm single loop. Upper gastrointestinal fiberscopy for annual follow-up revealed a type 0-IIc-shaped tumor with ulcer scar, 4.0 cm in size, located in the gastric remnant near the jejunogastrostomy. A clinical diagnosis of cancer of the gastric remnant, clinical T1b(SM)N0M0, Stage IA, following the proximal gastrectomy was made and a laparoscopic approach was selected because of the cancer's early stage. Remnant total gastrectomy with D1 plus lymphadenectomy was carried out with five ports by a pneumoperitoneal method. Complete resection of the reconstructed jejunum was undergone along with the jejunal mesentery. Reconstruction by the Roux-en-Y method via the antecolic route was selected. Total operative time was 395 min and blood loss was 40 mL. Our patient was the first successful case of resection for carcinoma of the gastric remnant following proximal gastrectomy reconstructed with jejunal interposition in a laparoscopic approach. PMID:27034881

  20. Jejunal morphology and blood metabolites in tail biting, victim and control pigs.

    PubMed

    Palander, P A; Heinonen, M; Simpura, I; Edwards, S A; Valros, A E

    2013-09-01

    Tail biting has several identified feeding-related risk factors. Tail biters are often said to be lighter and thinner than other pigs in the pen, possibly because of nutrition-related problems such as reduced feed intake or inability to use nutrients efficiently. This can lead to an increase in foraging behavior and tail biting. In this study, a total of 55 pigs of different ages were selected according to their tail-biting behavior (bouts/hour) and pen-feeding system to form eight experimental groups: tail-biting pigs (TB), victim pigs (V) and control pigs from a tail-biting pen (Ctb) and control pen (Cno) having either free access to feed with limited feeding space or meal feeding from a long trough. After euthanasia, a segment of jejunal cell wall was cut from 50 cm (S50) and 100 cm (S100) posterior to the bile duct. Villus height, crypt depth and villus : crypt ratio (V : C) were measured morphometrically. Blood serum concentration of minerals and plasma concentration of amino acids (AA) was determined. Villus height was greater in Cno than Ctb pigs in the proximal and mid-jejunum (P < 0.05), indicative of better ability to absorb nutrients, and increased with age in the proximal jejunum (P < 0.001). Serum mineral concentration of inorganic phosphate (Pi) and calcium (Ca) was lower in Ctb compared with Cno pigs, and that of Pi in V compared with all the other pigs. Many non-essential AA were lower in pigs from tail-biting pens, and particularly in victim pigs. Free access feeding with shared feeding space was associated with lower levels of essential AA in blood than meal feeding with simultaneous feeding space. Our data suggest that being a pig in a tail-biting pen is associated with decreased jejunal villus height and blood AA levels, possibly because of depressed absorption capacity, feeding behavior or environmental stress associated with tail biting. Victim pigs had lower concentrations of AA and Pi in plasma, possibly as a consequence of being bitten

  1. Rotating Wavepackets

    ERIC Educational Resources Information Center

    Lekner, John

    2008-01-01

    Any free-particle wavepacket solution of Schrodinger's equation can be converted by differentiations to wavepackets rotating about the original direction of motion. The angular momentum component along the motion associated with this rotation is an integral multiple of [h-bar]. It is an "intrinsic" angular momentum: independent of origin and…

  2. Jejunal Cancer with WRN Mutation Identified from Next-Generation Sequencing: A Case Study and Minireview

    PubMed Central

    Chang, Christopher; Shiah, Her-Shyong; Hsu, Nan-Yung; Huang, Hsiu-Ying; Chu, Jan-Show; Yen, Yun

    2014-01-01

    Small bowel cancer is a rare, gastrointestinal cancer originating from the small intestines. Carcinogenesis in the jejunum, the middle segment of the small intestines, occurs less commonly than in the duodenum and ileum. Despite the increasing incidences globally, the cancer is still poorly understood, which includes lack of pathological understanding and etiological reasoning, as it seems to exhibit both similarities and differences with other types of cancers. A 76-year-old Asian man was presented with abdominal pain, which was later attributed to an adenocarcinoma in the jejunum. Initial immunoreactive staining results found no connections to colorectal cancer. The microsatellite instability test was further examined by immunohistochemistry which revealed them to be wild-type. From our exome-capture sequencing results, mutations of WRN may be important as they represent the only genetic defect in this jejunal cancer. The patient has since undergone surgical resection of his cancer and is currently being treated with chemotherapy. The pathology, genomic markers, and treatments are described along with literature review. PMID:25018888

  3. Jejunal manometry in distal subacute mechanical obstruction: significance of prolonged simultaneous contractions.

    PubMed Central

    Camilleri, M

    1989-01-01

    The aim of this study is to assess the value of jejunal manometry in the diagnosis of subacute mechanical obstruction distal to the proximal small bowel. In a retrospective review of 850 manometric tracings carried out in patients with unexplained nausea, vomiting, abdominal pain or altered bowel movements, 16 tracings were identified with features suggestive of mechanical obstruction: prolonged simultaneous contractions (PC) and postprandial clustered contractions (CC). Three patients had CC lasting less than 20 minutes: none proved to have mechanical obstruction. Among seven patients with CC lasting more than 30 minutes, three had proven mechanical obstruction, one probable adhesion obstruction, and in three no obstruction was found. All three patients with PC and three with mixed PC and CC had mechanical obstruction. The obstructed intestine manifests a variety of pressure profiles in the proximal jejunum: PC, CC, or mixed patterns. Prolonged simultaneous contractions are suggestive of distal subacute bowel obstruction; CC lasting over 30 minutes are less specific, whereas CC lasting less than 20 minutes are not associated with obstruction. PMID:2714680

  4. Transition between columnar absorptive cells and goblet cells in the rat jejunal epithelium.

    PubMed

    Kurosumi, K; Shibuichi, I; Tosaka, H

    1981-11-01

    Electron microscopic observation of the jejunal epithelium of rats demonstrated morphological evidence of a transition between columnar absorptive cells and growing goblet cells. The columnar cells in both the villi and crypts have features suggestive of absorptive functions. They are provided with apical invaginations continuous to the intermicrovillous space. Absorbed lipid is observed in small vesicles in the terminal web layer, and chylomicrons derived here from are contained in large vacuoles near the Golgi apparatus. Ferritin particles artificially infused into the gut lumen were absorbed into the vacuoles in the subapical zone of columnar cells of suckling rats. Growing goblet cells situated in the crypt epithelium contain surface invaginations and lysosomes which are the same in structure as those found in absorptive cells nearby. Fat droplets evidently absorbed by the growing goblet cell were observed among immature mucus droplets. Artificially infused ferritin particles were found in vacuoles and lysosomes near the Golgi apparatus of some goblet cells of suckling rats. Some goblet cells on the intestinal villi of suckling rats looked immature and their microvilli and cytoplasmic matrix were clear like those of columnar absorptive cells. The transition between these goblet cells with clear cytoplasm and the mature goblet cells with dark cytoplasm was observed. These morphological evidences indicate that some of columnar cells already differentiated to absorptive cells are capable of transforming into mucus-producing (goblet) cells. It is suggested that not only undifferentiated columnar cells in the crypt base but also considerably differentiated columnar cells with absorptive function can differentiate into goblet cells.

  5. Jejunal hemorrhage syndrome in dairy and beef cattle: 11 cases (2001 to 2003)

    PubMed Central

    2005-01-01

    Abstract The medical records of 11 cattle with jejunal hemorrhage syndrome were reviewed. Female and male, lactating and pregnant, dairy and beef cattle were affected. Decreased feed intake and milk production, reduced amounts of dark feces, and abdominal discomfort were common historical findings. Common clinical findings included depressed demeanor, a “ping” and fluid-splashing sounds over the right abdomen, melena, and distended loops of intestine on rectal palpation. Surgery was done on 7 cases, 10 cases were euthanized, and 1 died. Clostridium perfringens type A was isolated from the intestinal contents from 7 of 7 cases. At necropsy, the characteristic finding was a varying length of a dark purple-red distended jejunum with an intraluminal blood clot. Histologically, there was segmental necrosis, ulceration, and mucosal and transmural hemorrhage of the jejunum. This is a sporadic disease of adult cattle characterized by mechanical obstruction of the small intestines by a large blood clot with a case fatality of almost 100%. PMID:16187715

  6. The lack of protective effects of tea supplementation on liver and jejunal epithelium in adult rats exposed to cadmium and lead.

    PubMed

    Tomaszewska, Ewa; Winiarska-Mieczan, Anna; Dobrowolski, Piotr

    2015-11-01

    Adult rats at the age of 12 weeks were divided into the control group and groups supplemented with green (GT), black (BT), red (RT), or white (WT) tea extracts. The diet (except that for the control) was mixed with 7 mg Cd/kg and 50 mg Pb/kg. The experiment lasted 12 weeks. Basal haematology and plasma biochemical parameters as well as the histomorphometrical parameters of jejunal epithelium and liver were determined. The lowest body mass was found in the RT and WT groups. Some functional (increased plasma ALT and AST, and the de Ritis coefficient) and structural changes in the liver (slight fatty degenerative changes, an increase in the intercellular space) were evident irrespective of the type of tea in the Cd and Pb poisoned rats. This toxic effect was visible especially in rats drinking black or red tea. However, the rats had no elevated LDH and ALT activities. The highest content of Cd and Pb in the liver and blood plasma was found in rats drinking red tea. Based on the results obtained, it is clear that long-term exposure of adult rats with a mature intestinal barrier to Cd and Pb contamination, under higher exposure conditions than the current estimates of weekly exposure of the general population to Cd and Pb through diet, causes a toxic effect, especially in the liver, and can change the structure of intestinal mucosa, irrespective of tea administration.

  7. Bio-sensing based on plasmon-coupling caused by rotated sub-micrometer gratings in metal-dielectric interfacial layers

    NASA Astrophysics Data System (ADS)

    Csete, M.; Sipos, Á.; Szalai, A.; Mathesz, A.; Deli, M. A.; Veszelka, Sz.; Schmatulla, A.; Kőházi-Kis, A.; Osvay, K.; Marti, O.; Bor, Zs.

    2007-09-01

    Novel plasmonic sensor chips are prepared by generating sub-micrometer periodic patterns in the interfacial layers of bimetal-polymer films via master-grating based interference method. Poly-carbonate films spin-coated onto vacuum evaporated silver-gold bimetallic layers are irradiated by the two interfering UV beams of a Nd:YAG laser. It is proven by pulsed force mode AFM that periodic adhesion pattern corresponds to the surface relief gratings, consisting of sub-micrometer droplet arrays and continuous polymer stripes, induced by p- and s-polarized beams, respectively. The characteristic periods are the same, but more complex and larger amplitude adhesion modulation is detectable on the droplet arrays. The polar and azimuthal angle dependence of the resonance characteristic of plasmons is studied by combining the prism- and grating-coupling methods in a modified Kretschmann arrangement, illuminating the structured metal-polymer interface by a frequency doubled Nd:YAG laser through a semi-cylinder. It is proven that the grating-coupling results in double-peaked plasmon resonance curves on both of the droplet arrays and line gratings, when the grooves are rotated to an appropriate azimuthal angle, and the modulation amplitude of the structure is sufficiently large. Streptavidin seeding is performed to demonstrate that small amount of protein can be detected monitoring the shift of the secondary resonance minima. The available high concentration sensitivity is explained by the promotion of protein adherence in the structure's valleys due to the enhanced adhesion. The line-shaped polymer gratings resulting in narrow resonance peaks are utilized to demonstrate the effect of therapeutic molecules on Amyloid-Β peptide, a pathogenic factor in Alzheimer disease.

  8. Rotational Energy.

    ERIC Educational Resources Information Center

    Lockett, Keith

    1988-01-01

    Demonstrates several objects rolling down a slope to explain the energy transition among potential energy, translational kinetic energy, and rotational kinetic energy. Contains a problem from Galileo's rolling ball experiment. (YP)

  9. Solar rotation.

    NASA Astrophysics Data System (ADS)

    Dziembowski, W.

    Sunspot observations made by Johannes Hevelius in 1642 - 1644 are the first ones providing significant information about the solar differential rotation. In modern astronomy the determination of the rotation rate is done in a routine way by measuring positions of various structures on the solar surface as well as by studying the Doppler shifts of spectral lines. In recent years a progress in helioseismology enabled determination of the rotation rate in the layers inaccessible for direct observations. There are still uncertainties concerning, especially, the temporal variations of the rotation rate and its behaviour in the radiative interior. We are far from understanding the observations. Theoretical works have not yet resulted in a satisfactory model for the angular momentum transport in the convective zone.

  10. A Rare Case of Jejunal Arterio-Venous Fistula: Treatment with Superselective Catheter Embolization with a Tracker-18 Catheter and Microcoils

    SciTech Connect

    Sonnenschein, Martin J. Anderson, Suzanne E.; Lourens, Steven; Triller, Juergen

    2004-11-15

    Arterio-venous fistulas may develop spontaneously, following trauma or infection, or be iatrogenic in nature. We present a rare case of a jejunal arterio- venous fistula in a 35-year-old man with a history of pancreatic head resection that had been performed two years previously because of chronic pancreatitis. The patient was admitted with acute upper abdominal pain, vomiting and an abdominal machinery-type bruit. The diagnosis of a jejunal arterio-venous fistula was established by MR imaging. Transfemoral angiography was performed to assess the possibility of catheter embolization. The angiographic study revealed a small aneurysm of the third jejunal artery, abnormal early filling of dilated jejunal veins and marked filling of the slightly dilated portal vein (13-14 mm). We considered the presence of segmental portal hypertension. The patient was treated with coil embolization in the same angiographic session. This case report demonstrates the importance of auscultation of the abdomen in the initial clinical examination. MR imaging and color Doppler ultrasound are excellent noninvasive tools in establishing the diagnosis. The role of interventional radiological techniques in the treatment of early portal hypertension secondary to jejunal arterio-venous fistula is discussed at a time when this condition is still asymptomatic. A review of the current literature is included.

  11. Glycoprotein degradation in the blind loop syndrome: identification of glycosidases in jejunal contents.

    PubMed

    Prizont, R

    1981-02-01

    Contents obtained from jejunum of normal controls, self-emptying and self-filling blind loop rats were analyzed for the presence of glycoprotein-degrading glycosidases. The blind loop syndrome was documented by the increased fat excretion and slower growth rate of self-filling blind loop rats 6 wk after surgery. With p-nitrophenylglycosides as substrate, the specific activity of alpha-N-acetylgalactosaminidase, a potential blood group A destroying glycosidase, was 0.90+/-0.40 mU/mg of protein. This level was 23-fold higher than the specific activity of normal controls. In partially purified self-filling blind loop contents, the activity of alpha-N-acetylgalactosaminidase was 9- to 70-fold higher than activities of self-emptying and normal controls. Antibiotic treatment with chloromycetin and polymyxin decreased 24-fold the glycosidase levels in self-filling blind loops. In experiments with natural substrate, the blood group A titer of a20,000g supernate from normal jejunal homogenates decreased 128-fold after 24-h incubation with blind loop contents. Normal contents failed to diminish the blood group reactivity of the natural substrate. Furthermore, blind loop contents markedly decreased the blood group A titer of isolated brush borders. Incubation between blind loop bacteria and mucosal homogenates or isolated brush borders labeled with d-[U-(14)C]glucosamine revealed increased production of labeled ether extractable organic acids. Likewise, intraperitoneal injection of d-[U-(14)C]glucosamine into self-filling blind loop rats resulted in incorporation of the label into luminal short chain fatty acids. These results suggest that glycosidases may provide a mechanism by which blind loop bacteria obtain sugars from intestinal glycoproteins. The released sugars are used and converted by bacteria into energy and organic acids. This use of the host's glycoproteins would allow blind loop bacteria to grow and survive within the lumen independent of exogenous sources.

  12. Small intestinal submucosa seeded with intestinal smooth muscle cells in a rodent jejunal interposition model

    PubMed Central

    Qin, Harry H.; Dunn, James C.Y.

    2011-01-01

    Background Small intestinal submucosa (SIS) is a porcine-derived, acellular, collagen-based matrix that has been tested without seeded smooth muscle cells (SMCs) for intestinal tissue engineering. We examined the expression patterns of contractile proteins of SIS with SMCs implanted in an in vivo rodent model. Materials and methods Intestinal SMCs were isolated from Lewis rat pups. Four-ply tubular SMCs-seeded SIS or blank SIS scaffolds were implanted in an adult rat jejunal interposition model. Recipients were sacrificed at 2, 4, and 8 weeks following the implantation. The retrieved specimens were examined using antibodies against contractile proteins of SMCs. Results Cultured intestinal SMCs expressed α-smooth muscle actin (α-SMA), calponin, and less smooth muscle myosin heavy chain (SM-MHC) in vitro. Cell-seeded SIS scaffolds contracted significantly over 8 weeks of implantation but were comparable to SIS scaffolds without cell seeding. Implanted cell-seeded SIS scaffolds at 2 weeks expressed extensive α-SMA, some calponin, and minimal SM-MHC. At 4 weeks, α-SMA-expressing cells decreased significantly, whereas calponin or SM-MHC expressing cells were rarely detected. A small number of α-SMA-expressing cells were present at 8 weeks, whereas more calponin or SM-MHC expressing cells emerged in proximity with the anastomotic interface. Conclusions Cell-seeded SIS contracted significantly after implantation, but the expressions of contractile proteins were present at the site of SIS interposition. No organized smooth muscle was formed at the site of implantation. A better scaffold design is needed to produce structured smooth muscle. PMID:21937060

  13. Intracellular potassium as a possible inducer of amino acid transport across hamster jejunal enterocytes.

    PubMed Central

    Cremaschi, D; James, P S; Meyer, G; Rossetti, C; Smith, M W

    1986-01-01

    Brush border membrane potentials (Vm), intracellular K+ activity (aiK) and alanine uptake were measured in different parts of villi in mid-jejunal tissue taken from hamsters fed different amounts of food at high and low environmental temperatures. Basal villus enterocytes (Y cells) were found to have lower values for Vm and aiK than upper villus enterocytes (O cells). Alanine uptake was confined to O cells. The position on the villus where values for Vm and aiK changed, and where alanine uptake could first be seen to take place, depended on the energy intake and environmental temperature at which hamsters were kept. Na+-dependent alanine uptake and Vm were both higher in O cells of hamsters fed 10 kcal day-1 at 30 degrees C (10 k/30 degrees C) compared with animals fed 30 kcal day-1 at an environmental temperature of 12 degrees C (30 k/12 degrees C hamsters). The rates at which enterocytes migrated along the crypt-villus axis, measured separately in thymidine-labelling experiments, were 6.9 and 16.1 micron h-1 for 10 k/30 degrees C and 30 k/12 degrees C hamsters respectively. Both Vm and aiK were estimated, from these measurements, to have increased significantly by the time enterocytes became 30 h old. Alanine uptake began 15 h later. Neither of these parameters were influenced by previous adaptation conditions. The close temporal and variable positional relationship found between changes in aiK and onset of transport suggests that early changes in electrolyte composition might initiate a second phase of development enabling the enterocyte to absorb nutrients. The possibility that other ions besides K+ might also be involved in this aspect of regulation is also discussed. PMID:3795055

  14. Endocrine effects of duodenal-jejunal exclusion in obese patients with type 2 diabetes mellitus.

    PubMed

    Kaválková, Petra; Mráz, Miloš; Trachta, Pavel; Kloučková, Jana; Cinkajzlová, Anna; Lacinová, Zdeňka; Haluzíková, Denisa; Beneš, Marek; Vlasáková, Zuzana; Burda, Václav; Novák, Daniel; Petr, Tomáš; Vítek, Libor; Pelikánová, Terezie; Haluzík, Martin

    2016-10-01

    Duodenal-jejunal bypass liner (DJBL) is an endoscopically implantable device designed to noninvasively mimic the effects of gastrointestinal bypass operations by excluding the duodenum and proximal jejunum from the contact with ingested food. The aim of our study was to assess the influence of DJBL on anthropometric parameters, glucose regulation, metabolic and hormonal profile in obese patients with type 2 diabetes mellitus (T2DM) and to characterize both the magnitude and the possible mechanisms of its effect. Thirty obese patients with poorly controlled T2DM underwent the implantation of DJBL and were assessed before and 1, 6 and 10months after the implantation, and 3months after the removal of DJBL. The implantation decreased body weight, and improved lipid levels and glucose regulation along with reduced glycemic variability. Serum concentrations of fibroblast growth factor 19 (FGF19) and bile acids markedly increased together with a tendency to restoration of postprandial peak of GLP1. White blood cell count slightly increased and red blood cell count decreased throughout the DJBL implantation period along with decreased ferritin, iron and vitamin B12 concentrations. Blood count returned to baseline values 3months after DJBL removal. Decreased body weight and improved glucose control persisted with only slight deterioration 3months after DJBL removal while the effect on lipids was lost. We conclude that the implantation of DJBL induced a sustained reduction in body weight and improvement in regulation of lipid and glucose. The increase in FGF19 and bile acids levels could be at least partially responsible for these effects. PMID:27474690

  15. Transition between columnar absorptive cells and goblet cells in the rat jejunal epithelium.

    PubMed

    Kurosumi, K; Shibuichi, I; Tosaka, H

    1981-11-01

    Electron microscopic observation of the jejunal epithelium of rats demonstrated morphological evidence of a transition between columnar absorptive cells and growing goblet cells. The columnar cells in both the villi and crypts have features suggestive of absorptive functions. They are provided with apical invaginations continuous to the intermicrovillous space. Absorbed lipid is observed in small vesicles in the terminal web layer, and chylomicrons derived here from are contained in large vacuoles near the Golgi apparatus. Ferritin particles artificially infused into the gut lumen were absorbed into the vacuoles in the subapical zone of columnar cells of suckling rats. Growing goblet cells situated in the crypt epithelium contain surface invaginations and lysosomes which are the same in structure as those found in absorptive cells nearby. Fat droplets evidently absorbed by the growing goblet cell were observed among immature mucus droplets. Artificially infused ferritin particles were found in vacuoles and lysosomes near the Golgi apparatus of some goblet cells of suckling rats. Some goblet cells on the intestinal villi of suckling rats looked immature and their microvilli and cytoplasmic matrix were clear like those of columnar absorptive cells. The transition between these goblet cells with clear cytoplasm and the mature goblet cells with dark cytoplasm was observed. These morphological evidences indicate that some of columnar cells already differentiated to absorptive cells are capable of transforming into mucus-producing (goblet) cells. It is suggested that not only undifferentiated columnar cells in the crypt base but also considerably differentiated columnar cells with absorptive function can differentiate into goblet cells. PMID:7325782

  16. Jejunal free flap for reconstruction of pharyngeal defects in patients with head and neck cancer-the Birmingham experience.

    PubMed

    Walker, Rachel J; Parmar, Satyesh; Praveen, Prav; Martin, Tim; Pracy, Paul; Jennings, Chris; Simms, Malcolm

    2014-02-01

    We retrospectively audited operative complications, success of flaps, and speech and swallowing outcomes in patients with head and neck cancer who had reconstruction with jejunal free tissue transfer to the pharynx. A total of 104 patients had jejunal free flaps between 1987 and 2009 at University Hospital, Birmingham. Management was by a multidisciplinary team, and the same vascular surgeon did all the anastomoses. We investigated the relations between patients, operative factors, and postoperative complications, and noted the ischaemic time of the flaps and coexisting conditions of the patients. Outcomes measured included initial and final survival rates of flaps, donor and recipient site complications, and speech and swallowing outcomes on discharge and up to 2 years postoperatively. Of the 104 patients, 14 (13%) had initial flap complications but overall flap survival was 97%. A total of 11 (11%) patients developed a fistula at a mean of 15 days postoperatively and 11 (11%) had minor donor site complications. A total of 95 (91%) were able to resume oral diet on discharge. Of the 44 who were followed up on discharge, 32 (73%) were able to maintain oral intake at 2 years and 31 (70%) could use their voice in everyday situations. The jejunal free flap enables the tumour to be removed, and reconstruction and restoration of function to be done in a single operation using tissue that is versatile. The operation is associated with low morbidity at the donor and recipient sites, and results in good speech and swallowing outcomes. The flap can also be used to reconstruct pharyngolaryngeal defects.

  17. Jejunal free flap for reconstruction of pharyngeal defects in patients with head and neck cancer-the Birmingham experience.

    PubMed

    Walker, Rachel J; Parmar, Satyesh; Praveen, Prav; Martin, Tim; Pracy, Paul; Jennings, Chris; Simms, Malcolm

    2014-02-01

    We retrospectively audited operative complications, success of flaps, and speech and swallowing outcomes in patients with head and neck cancer who had reconstruction with jejunal free tissue transfer to the pharynx. A total of 104 patients had jejunal free flaps between 1987 and 2009 at University Hospital, Birmingham. Management was by a multidisciplinary team, and the same vascular surgeon did all the anastomoses. We investigated the relations between patients, operative factors, and postoperative complications, and noted the ischaemic time of the flaps and coexisting conditions of the patients. Outcomes measured included initial and final survival rates of flaps, donor and recipient site complications, and speech and swallowing outcomes on discharge and up to 2 years postoperatively. Of the 104 patients, 14 (13%) had initial flap complications but overall flap survival was 97%. A total of 11 (11%) patients developed a fistula at a mean of 15 days postoperatively and 11 (11%) had minor donor site complications. A total of 95 (91%) were able to resume oral diet on discharge. Of the 44 who were followed up on discharge, 32 (73%) were able to maintain oral intake at 2 years and 31 (70%) could use their voice in everyday situations. The jejunal free flap enables the tumour to be removed, and reconstruction and restoration of function to be done in a single operation using tissue that is versatile. The operation is associated with low morbidity at the donor and recipient sites, and results in good speech and swallowing outcomes. The flap can also be used to reconstruct pharyngolaryngeal defects. PMID:24315201

  18. Temporary Trans-jejunal Hepatic Duct Stenting in Roux-en-y Hepaticojejunostomy for Reconstruction of Iatrogenic Bile Duct Injuries

    PubMed Central

    Sadegh Fazeli, Mohammad; Kazemeini, Ali Reza; Jafarian, Ali; Bashashati, Mohammad; Keramati, Mohammad Reza

    2016-01-01

    Background Bile Duct Injuries (BDI) during cholecystectomy are now being recognized as major health problems. Objectives Herein, we present our experience with handling major BDIs and report long-term outcome of hepaticojejunostomies followed by trans-jejunal hepatic duct stenting performed to reconstruct extra-hepatic biliary tracts. Materials and Methods In this case series, we prospectively collected data of 22 patients, who underwent first time biliary reconstruction through Roux-en-y hepaticojejunostomy followed by hepatic duct stenting using a trans-jejunal bifurcated 6F tube drain. The long-term outcome was assessed and defined as excellent (asymptomatic, normal liver enzymes and bilirubin levels), good (asymptomatic, mild abnormality in liver enzyme and bilirubin levels), poor (symptomatic, abnormal liver enzymes and bilirubin level) and failure (requiring reoperation). Results A total of 22 patients including four males (18.1%) and 18 females (81.8%) were evaluated. The mean age was 42.71 (range: 23 - 74) years. Twelve patients had undergone open cholecystectomy (54.5%) and the rest had a history of laparoscopic cholecystectomy. The mean interval between the primary operation and reconstruction was 92.71 days. The mean follow-up period after biliary reconstruction was 42.33 (range: 1 - 96) months. No instance of anastomotic leakage or stenosis, biliary sepsis, thromboembolic event, or respiratory infection was noted in the long-term follow-up. The outcome was excellent in all patients. No case with poor or failure of result was noticed. Conclusions Although a devastating complication iatrogenic major bile duct injuries can be corrected surgically with a high rate of success. Temporary trans-jejunal stenting of the hepatic ducts can help in maintaining the integrity of anastomosis without stenosis or biliary sepsis. PMID:27626003

  19. Jejunal mucosal lactase activity from birth to three weeks in conventionally raised calves fed an electrolyte solution on days 5, 6 and 7 instead of milk.

    PubMed

    St Jean, G D; Schmall, L M; Rings, D M; Hoffsis, G F; Hull, B L

    1991-01-01

    The purpose of this study was to evaluate the effect of withdrawal of lactose from the diet for 72 hours on lactase activity in the jejunal mucosa of conventionally raised calves. The descending portion of the duodenum of six Holstein calves less than 24 hours old was cannulated. The calves were fed milk except on days 5, 6 and 7 when they were given the same volume of an electrolyte solution. Sequential biopsy specimens of the proximal jejunal mucosa were obtained for three weeks and the lactase activity determined. Lactase activity was highest on day 1 and a trend toward decreased lactase activity from birth until three weeks was observed. Mean lactase activity was significantly (p less than 0.05) higher for days 1, and 3 compared to days 9, 13 and 17. The withdrawal of milk and replacement by an electrolyte solution during three days had no significant effect on jejunal mucosal lactase activity in neonatal calves.

  20. Jejunal stricture: a rare complication of chemotherapy in pediatric gastrointestinal B-cell non-Hodgkin lymphoma.

    PubMed

    Gupta, Gaurav; Agarwala, Sandeep; Thulkar, Sanjay; Shukla, Bhaskar; Bakhshi, Sameer

    2011-03-01

    The use of intensive chemotherapy has led to remarkable improvements in the treatment of high-grade B-cell Non-Hodgkin lymphoma (NHL); however, it is associated with significant side effects such as myelosuppression and mucositis. Gastrointestinal NHL rarely leads to the development of aneurysmal dilatation of the bowel, as desmoplastic reaction is not a feature of NHL. Strictures and fibrosis are not a manifestation of NHL involvement. Here, we report a child with primary gastrointestinal B-cell NHL who presented with jejunal stricture developing as a sequela of severe chemotherapy-induced mucositis. The patient improved with surgical resection of stricture and end-to-end anastomosis. PMID:21127430

  1. The deconjugation ability of bacteria isolated from the jejunal fluids in the blind loop syndrome with high 14CO2 excretion--using the breath analysis technique and thin-layer chromatography.

    PubMed

    Shindo, K; Yamazaki, R; Mizuno, T; Shionoiri, H; Sugiyama, M

    1989-01-01

    Five patients with blind loop syndrome (Billroth II) were examined by measuring 14CO2 specific activity of expired breath samples taken at intervals after a meal containing glycine-1-14C cholate. The 5 patients tested showed a marked increase of 14CO2 specific activity. Furthermore, the ability of deconjugation of bacteria isolated from the jejunal fluids in the efferent loop of these patients was tested by thin layer chromatography. The bacterial species identified from the samples were as follows: enterococcus, Lactobacillus (L) buchneri, L. bifidus, L. brevis, Eubacterium (E) lentum, Bacteroides (B) vulgaricus, B. filamentosum, Corynebacterium (C) granulosum, Escherichia (E) coli, Staphylococcus (S) epidermidis, and Aerobacter (A) aerogenes. These species of bacteria, except E. coli and A. aerogenes, showed the deconjugation ability by which conjugated bile acids in ox gall was hydrolyzed. Administration of chloramphenicol (1g per day for 14 days orally divided doses) to the 5 patients reduced 14CO2 specific activity significantly. On the other hand, 9 healthy men (control subjects) who were tested showed a flat curve, and 8 of the 9 had no growth of bacteria isolated from the jejunal fluids. The remaining healthy man showed an overgrowth of E. coli and Pseudomonas (P) aeruginosa, but the species did not have the ability of deconjugation. Thus, we concluded that the patients with blind loop syndrome(Billroth II) had the bacterial overgrowth in the efferent loop that contained species with deconjugation ability, and, as a result the bacterial overgrowth contributed to causing abnormalities (increased deconjugation) in the metabolism of bile acids in the small intestine. When the concentration of conjugated bile acids in the small intestine was reduced to levels below the critical micellar concentration by several factors, fat malabsorption and subsequent steatorrhea were induced (1,-4). Furthermore, H. Fromm and A. F. Hofmann presented in vivo that the patients

  2. Biologics in rotator cuff surgery

    PubMed Central

    Schär, Michael O; Rodeo, Scott A

    2014-01-01

    Pathologies of the rotator cuff are by far the most common cause of shoulder dysfunction and pain. Even though reconstruction of the rotator cuff results in improved clinical outcome scores, including decreased pain, several studies report high failure rates. Orthopaedic research has therefore focused on biologically augmenting the rotator cuff reconstruction and improving tendon–bone healing of the rotator cuff. This biological augmentation has included the application of different platelet concentrates containing growth factors, mesenchymal stem cells, scaffolds and a combination of the above. The present review provides an overview over the biological augmentation options based upon current evidence. PMID:27582941

  3. Earth Rotation

    NASA Technical Reports Server (NTRS)

    Dickey, Jean O.

    1995-01-01

    The study of the Earth's rotation in space (encompassing Universal Time (UT1), length of day, polar motion, and the phenomena of precession and nutation) addresses the complex nature of Earth orientation changes, the mechanisms of excitation of these changes and their geophysical implications in a broad variety of areas. In the absence of internal sources of energy or interactions with astronomical objects, the Earth would move as a rigid body with its various parts (the crust, mantle, inner and outer cores, atmosphere and oceans) rotating together at a constant fixed rate. In reality, the world is considerably more complicated, as is schematically illustrated. The rotation rate of the Earth's crust is not constant, but exhibits complicated fluctuations in speed amounting to several parts in 10(exp 8) [corresponding to a variation of several milliseconds (ms) in the Length Of the Day (LOD) and about one part in 10(exp 6) in the orientation of the rotation axis relative to the solid Earth's axis of figure (polar motion). These changes occur over a broad spectrum of time scales, ranging from hours to centuries and longer, reflecting the fact that they are produced by a wide variety of geophysical and astronomical processes. Geodetic observations of Earth rotation changes thus provide insights into the geophysical processes illustrated, which are often difficult to obtain by other means. In addition, these measurements are required for engineering purposes. Theoretical studies of Earth rotation variations are based on the application of Euler's dynamical equations to the problem of finding the response of slightly deformable solid Earth to variety of surface and internal stresses.

  4. Ectopic Jejunal Variceal Rupture in a Liver Transplant Recipient Successfully Treated With Percutaneous Transhepatic Coil Embolization: A Case Report.

    PubMed

    Abe, Satoru; Akamatsu, Nobuhisa; Hoshikawa, Mayumi; Shirata, Chikara; Sakamoto, Yoshihiro; Hasegawa, Kiyoshi; Kokudo, Norihiro

    2015-11-01

    Here we present the rupture of ectopic jejunal varices developing in a liver transplant recipient without portal hypertension, which was successfully treated with percutaneous transhepatic coil embolization.A 48-year-old man with massive melena was admitted to our department. He had undergone liver transplantation for hepatitis B virus-related liver cirrhosis 8 months before, and his postoperative course was satisfactory except for an acute cellular rejection. No evidence of bleeding was detected by upper endoscopy or colonoscopy, but dynamic multidetector computed tomography of the whole abdomen revealed an intestinal varix protruding into the lumen of the jejunum with suspected extravasation. There was no evidence of portal venous stenosis or thrombosis. Immediately upon diagnosis of the ruptured ectopic jejunal varix, percutaneous transhepatic coil embolization was performed, achieving complete hemostasis. The portal venous pressure measured during the procedure was within normal limits. He was discharged from the hospital 11 days after embolization and remained in stable condition without re-bleeding 6 months after discharge.This is the first report of an ectopic intestinal variceal rupture in an uneventful liver transplant recipient that was successfully treated with interventional percutaneous transhepatic coil embolization. Clinicians encountering liver transplant recipients with melena should be aware of the possibility of late-onset rupture of ectopic varices, even in those having an uneventful post-transplant course without portal hypertension. PMID:26632745

  5. Faraday rotation due to quadratic gravitation

    NASA Astrophysics Data System (ADS)

    Chen, Yihan; Liu, Liping; Tian, Wen-Xiu

    2011-01-01

    The linearized field equations of quadratic gravitation in stationary space-time are written in quasi-Maxwell form. The rotation of the polarization plane for an electromagnetic wave propagating in the gravito-electromagnetic field caused by a rotating gravitational lens is discussed. The influences of the Yukawa potential in quadratic gravitation on the gravitational Faraday rotation are investigated.

  6. Influence of dietary supplementation with flaxseed and lactobacilli on the mucosal morphology and proliferative cell rate in the jejunal mucosa of piglets after weaning.

    PubMed

    Jonecova, Zuzana; Toth, Stefan; Ciccocioppo, Rachele; Rodrigo, Luis; Kruzliak, Peter; Nemcova, Radomira

    2015-06-01

    The aim of the study was to investigate the influence of flaxseed and lactobacilli supplementation to the diet of piglets during the time period between 10 days before and 21 days after weaning. The morphometry of the jejunal mucosa and proliferative ratio of both epithelial and lamina propria cells were compared with those found in a group of piglets fed with the usual diet added with sunflower oil during the same time period. The addition of flaxseed oil to the diet significantly increased the crypt depth in comparison with both groups supplemented with sunflower (P < 0.05 and 0.001 respectively) on the weaning day. Moreover, the flaxseed addition caused a significant decrease in villus height (P < 0.01) and crypt depth (P < 0.01) 21 days postweaning in comparison with the sunflower group. The proliferative ratio of the epithelial cells in the sunflower group on the weaning day was significantly higher than in both flaxseed groups (P < 0.01). Paradoxically, significantly higher proliferative activity in the mucosal connective tissue in the group with flaxseed supplementation in comparison with the sunflower group was observed on the day of weaning, as well as 3 days later (P < 0.05 both). A combination of flaxseed with lactobacilli showed significantly lower proliferative activity in the connective tissue cells from weaning up to 7 days after weaning (P < 0.05 all) in comparison with the flaxseed group.

  7. Jejunal linoleic acid infusions require GLP-1 receptor signaling to inhibit food intake: implications for the effectiveness of Roux-en-Y gastric bypass

    PubMed Central

    Moghadam, Alexander A.; Moran, Timothy H.

    2011-01-01

    Roux-en-Y gastric bypass surgery results in sustained decreases in food intake and weight loss. A key component is likely the direct delivery of nutrients to the jejunum and resulting changes in levels of gut peptide secretion. Prior work modeling this aspect of the surgery has shown that small-volume, prolonged jejunal infusions of linoleic acid (LA) produce sustained decreases in food intake and weight loss. LA infusions also significantly elevate plasma glucagon-like peptide-1 (GLP-1) levels. To assess a role for the increased circulating GLP-1 in the feeding suppression, we examined the effect of prolonged peripheral minipump administration of the GLP-1 receptor antagonist exendin 9–39 (Ex 9) on the feeding suppression produced by jejunal LA. Using a 2 × 2 design, we infused either saline or LA in the jejunum (7 h/day, 11.4 kcal) for 5 days with a subset of animals from each group receiving either saline or Ex 9 (25 pmol·kg−1·min−1) continuously via a minipump. The antagonist alone had no effect on food intake. LA reduced daily food intake greatly in excess of the kilocalories infused. Ex 9 completely blocked the feeding suppression produced by the jejunal LA infusion. Ex 9 also attenuated the increase in plasma GLP-1 induced by jejunal LA infusions. These data demonstrate that endogenous GLP-1 receptor signaling is necessary for the reduction in food intake produced by jejunal LA infusions. Whether increased secretion of additional gut peptides is also necessary for such suppressions remains to be determined. PMID:21917638

  8. Bleeding peptic ulcer caused by ectopic gastric mucosa in a duplicated segment of jejunum

    SciTech Connect

    Newmark, H.; Ching, G.; Halls, J.; Levy, I.J.

    1981-02-01

    The authors present a case in which a patient suffered a bleeding jejunal ulcer caused by heterotopic gastric mucosa in a congenital duplication of a segment of jejunum. This is the first case diagnosed preoperatively by two different radiographic means. These lesions were shown by both pertechnetate flow and barium small bowel studies. The rarity of these entities and the modalities used for diagnosis are described.

  9. Influence of dietary supplementation with flaxseed and lactobacilli on the cells of local innate immunity response in the jejunal mucosa in piglets after weaning.

    PubMed

    Toth, Stefan; Jonecova, Zuzana; Kruzliak, Peter; Ciccocioppo, Rachele; Nemcova, Radomira

    2015-03-01

    A histological study was designed to determine the influence of flaxseed and/or lactobacilli inclusion in the diet of piglets from 10 days before to 21 days after weaning. The selected inflammatory cell population incidence in the piglet jejunal mucosa was investigated. Significantly higher numbers of myeloperoxidase-positive (P<0.01) and CD163-positive (P<0.001) cells in the jejunal mucosa were recorded on the weaning day and for 7 days after (P<0.001 and P<0.01, respectively) in the flaxseed group compared with the basal diet. The number of intraepithelial lymphocytes was also significantly increased until 3 days after weaning (P<0.001). A prolonged significant increase in the myeloperoxidase-positive cells and intraepithelial lymphocyte numbers in the flaxseed+lactobacilli group was detected. In contrast, the number of CD163-positive cells in the flaxseed+lactobacilli group was significantly lower on the day of weaning (P<0.05) and 3 days after (P<0.01). The same effect was observed in the group with lactobacilli alone during the first 3 days after weaning (P<0.05 and P<0.01, respectively) and these findings indicate down-regulation of CD163 expression in the jejunal mucosa by lactobacilli. The presence of lactobacilli in the diet had a stimulatory effect on goblet cell quantity in the epithelium (P<0.001) and a distinct 50% reduction in the flaxseed group (P<0.01) compared with the basal diet was observed on the weaning day. A significant increase in myeloperoxidase-positive cell number in the jejunal mucosa in the flaxseed+lactobacilli group was the only significant difference (P<0.05 and P<0.01, respectively) found 21 days after weaning in comparison with all the other groups, indicating the pro-inflammatory effect of this feed additive combination. We conclude that dietary supplementation with flaxseed and lactobacilli on the cells of local innate immunity response in the jejunal mucosa in piglets after weaning might be linked with significant anti

  10. Mucosal intra-epithelial lymphocytes in enteropathy-associated T-cell lymphoma, ulcerative jejunitis, and refractory celiac disease constitute a neoplastic population.

    PubMed

    Bagdi, E; Diss, T C; Munson, P; Isaacson, P G

    1999-07-01

    Loss of response to a gluten-free diet (refractory sprue) and ulcerative jejunitis are complications of celiac disease that may progress to enteropathy-associated T-cell lymphoma (EATL). Both conditions are characterized by the presence of a nonlymphomatous monoclonal T-cell population in the enteropathic mucosa. In EATL, a similar monoclonal population that shows clonal identity with the lymphoma itself is also present in the enteropathic mucosa. In this study we show that in all three circumstances the monoclonal T-cell population is constituted by cytologically normal, noninvasive intraepithelial T lymphocytes that share an identical aberrant immunophenotype with EATL. Patients with refractory sprue and/or ulcerative jejunitis are, therefore, suffering from a neoplastic T-cell disorder for which hematological treatment strategies need to be devised.

  11. Rotating Apparatus for Isoelectric Focusing

    NASA Technical Reports Server (NTRS)

    Bier, M.

    1986-01-01

    Remixing of separated fractions prevented. Improved isoelectric focusing apparatus helps to prevent electro-osmosis and convection, both of which cause remixing of separated fractions. Fractionating column segmented and rotated about horizontal axis: Only combined effects of both features fully effective in making good separations. Improved apparatus slowly rotated continuously or rocked (at rotational amplitude of at least 180 degrees) about its horizontal axis so average gravitational vector experienced by fluid is zero and convection is therefore suppressed. Electro-osmosis suppressed and convection further suppressed by separating column into disklike compartments along its length with filters. Experiments have shown dimensions of apparatus not critical. Typical compartment and column volumes are 2 and 40 ml, respectively. Rotation speeds lie between 3 and 30 rpm.

  12. Rotator Cuff Tears

    MedlinePlus

    ... doctors because of a rotator cuff problem. A torn rotator cuff will weaken your shoulder. This means ... or more of the rotator cuff tendons is torn, the tendon no longer fully attaches to the ...

  13. Locomotion gaits of a rotating cylinder pair

    NASA Astrophysics Data System (ADS)

    van Rees, Wim M.; Novati, Guido; Koumoutsakos, Petros; Mahadevan, L.

    2015-11-01

    Using 2D numerical simulations of the Navier-Stokes equations, we demonstrate that a simple pair of rotating cylinders can display a range of locomotion patterns of biological and engineering interest. Steadily counter-rotating the cylinders causes the pair to move akin to a vortex dipole for low rotation rates, but as the rotational velocity is increased the direction of motion reverses. Unsteady rotations lead to different locomotion gaits that resemble jellyfish (for in-phase rotations) and undulating swimmers (for out-of-phase rotations). The small number of parameters for this simple system allows us to systematically map the phase space of these gaits, and allows us to understand the underlying physical mechanisms using a minimal model with implications for biological locomotion and engineered analogs.

  14. Enteroscopic Tattooing for Better Intraoperative Localization of a Bleeding Jejunal GIST Facilitates Minimally Invasive Laparoscopically-assisted Surgery.

    PubMed

    Iacob, Razvan; Dimitriu, Anca; Stanciulea, Oana; Herlea, Vlad; Popescu, Irinel; Gheorghe, Cristian

    2016-03-01

    We present the case of a 63-year-old man that was admitted for melena and severe anemia. Upper GI endoscopy and colonoscopy failed to identify the lesion responsible for bleeding, and enteroCT scan was also non-contributive to the diagnosis. Capsule endoscopy indicated possible jejunal bleeding but could not indicate the source of bleeding, recommending anterograde enteroscopy. Single balloon enteroscopy identified a 2 cm submucosal tumour in the distal part of the jejunum, with a macroscopic appearance suggesting a gastrointestinal stromal tumour (GIST). The tumor location was marked using SPOT tattoo and subsequently easily identified by the surgeon and resected via minimally invasive laparoscopic-assisted approach. Histological and immunohistochemical analysis indicated a low risk GIST. The unusual small size of the GIST as a modality of presentation, with digestive bleeding and anemia and the ability to use VCE/enteroscopy to identify and mark the lesion prior to minimally invasive surgery, represent the particularities of the presented case. PMID:27014761

  15. Studies of intestinal lymphoid tissue. VII. The secondary nature of lymphoid cell "activation" in the jejunal lesion of tropical sprue.

    PubMed

    Marsh, M N; Mathan, M; Mathan, V I

    1983-09-01

    Morphometric techniques were used in the evaluation of lymphocyte morphology and activity in tropical sprue. jejunal biopsies from control subjects (8), patients with epidemic disease (7), patients with endemic disease (11), and subjects who had recovered from sprue (4) were analyzed blindly. In patients with sprue, lymphocytes were increased significantly within crypt (but not surface) epithelium. Immunoblasts (greater than 6 mu in diameter) were increased by 5% over control subjects. Group means for lymphocytic mitotic indexes were also significantly raised, while flux ratios only differed significantly between endemic sprue patients and control subjects. The lymphocytic infiltration was distributed focally in the upper crypt and crypt-villus interzones. Analysis of epidemic cases (presenting within 4-28 days) revealed detectable changes in lymphocyte behavior only after 3 weeks' illness, whereas mucosal lesions and malabsorption were already established during the first week. These data indicate that lymphocyte activation, suggestive of a local cell-mediated immune reaction, does occur in tropical sprue but is secondary to damage already inflicted on enterocytes and their function.

  16. Studies of intestinal lymphoid tissue. VII. The secondary nature of lymphoid cell "activation" in the jejunal lesion of tropical sprue.

    PubMed Central

    Marsh, M. N.; Mathan, M.; Mathan, V. I.

    1983-01-01

    Morphometric techniques were used in the evaluation of lymphocyte morphology and activity in tropical sprue. jejunal biopsies from control subjects (8), patients with epidemic disease (7), patients with endemic disease (11), and subjects who had recovered from sprue (4) were analyzed blindly. In patients with sprue, lymphocytes were increased significantly within crypt (but not surface) epithelium. Immunoblasts (greater than 6 mu in diameter) were increased by 5% over control subjects. Group means for lymphocytic mitotic indexes were also significantly raised, while flux ratios only differed significantly between endemic sprue patients and control subjects. The lymphocytic infiltration was distributed focally in the upper crypt and crypt-villus interzones. Analysis of epidemic cases (presenting within 4-28 days) revealed detectable changes in lymphocyte behavior only after 3 weeks' illness, whereas mucosal lesions and malabsorption were already established during the first week. These data indicate that lymphocyte activation, suggestive of a local cell-mediated immune reaction, does occur in tropical sprue but is secondary to damage already inflicted on enterocytes and their function. Images Figure 3 Figure 4 Figure 5 PMID:6614143

  17. Raised number of jejunal IgG2-producing cells in untreated adult coeliac disease compared with food allergy.

    PubMed Central

    Rognum, T O; Kett, K; Fausa, O; Bengtsson, U; Kilander, A; Scott, H; Gaarder, P I; Brandtzaeg, P

    1989-01-01

    The subclass distribution of IgG-producing immunocytes was studied by two colour immunohistochemistry with monoclonal antibodies in jejunal biopsy specimens from 10 adults with untreated coeliac disease, 11 coeliac disease patients on a gluten free diet, and seven patients with established food allergy. Paired immunofluorescence staining was performed with subclass specific murine monoclonal antibodies in combination with polyclonal rabbit antibody reagent to total IgG; the proportion of cells belonging to each subclass could thereby be determined. The ratio of IgG2 immunocytes was significantly higher (p less than 0.05) in untreated coeliac disease patients (median, 35.2%; range, 26.7-65.2%) than in those on a gluten free diet (median, 7.3%; range, 0-31.9%) or those having food allergy (median, 12.5%; range, 0-36.5%). The disparity in the local IgG2 response between patients with untreated coeliac disease and those with food allergy might be due to differences in the nature of the antigenic stimuli, dissimilar genetic 'make-up' of the subjects, or both. Images Fig. 2 PMID:2599444

  18. Sutureless jejuno-jejunal anastomosis in gastric cancer patients: a comparison with handsewn procedure in a single institute

    PubMed Central

    2012-01-01

    Background The biofragmentable anastomotic ring has been used to this day for various types of anastomosis in the gastrointestinal tract, but it has not yet achieved widespread acceptance among surgeons. The purpose of this retrospective study is to compare surgical outcomes of sutureless with suture method of Roux-and-Y jejunojejunostomy in patients with gastric cancer. Methods Two groups of patients were obtained based on anastomosis technique (sutureless group versus hand sewn group): perioperative outcomes were recorded for every patient. Results The mean time spent to complete a sutureless anastomosis was 11±4 min, whereas the time spent to perform hand sewn anastomosis was 23±7 min. Estimated intraoperative blood loss was 178±32ml in the sutureless group and 182±23ml in the suture-method group with no significant differences. No complications were registered related to enteroanastomosis. Intraoperative mortality was none for both groups. Conclusions The Biofragmentable Anastomotic Ring offers a safe and time-saving method for the jejuno-jejunal anastomosis in gastric cancer surgery, and for this purpose the ring has been approved as a standard method in our clinic. Nevertheless currently there are few studies on upper gastrointestinal sutureless anastomoses and this could be the reason for the low uptake of this device. PMID:23173807

  19. A very feasible alternative in patients with feeding difficulties from gastrostomy: Jejunal tube advanced through the gastrostomy

    PubMed Central

    Karabulut, Ramazan; Turkyilmaz, Zafer; Sonmez, Kaan; Oktar, Suna Ozhan; Kaya, Cem; Kokurcan, Atilla; Oncu, Fatih; Basaklar, Abdullah Can

    2015-01-01

    Background: Our aim is to share our experiences regarding patients who cannot be fed effectively through the gastrostomy tube, but were inserted feeding jejunostomy through the gastrostomy orifice using scopic fluoroscopic techniques utilised by the interventional radiology. Patients and Methods: Between January 2010 and May 2013 the patients that were inserted jejunostomy tube through the gastrostomy orifice using fluoroscopic techniques were retrospectively analysed. Data including primary indication for gastrostomy, sex, concomitant disease and the requirement for gastroesophageal reflux disease (GERD) were all recorded. Results: There were five patients with these criteria. They all received either medical or surgical GERD therapy; nevertheless enteral feeding failed to reach an effective level, they all had vomiting and did not gain any weight. Following conversion, all the patients gained minimum 2 kg in 2-5 months; all the patients tolerated enteral feeding and were discharged in the early period. There were neither procedure related complications such as perforation, bleeding nor sedation related complications. Procedure took no more than 30 min as a whole. There was no need for surgical intervention. However in one patient re-intervention was required due to accidental removal of the catheter. Conclusions: In case of feeding difficulties following the gastrostomy; instead of an invasive surgical intervention; physicians should consider jejunal feeding that is advanced through the gastrostomy, which does not require any anaesthesia. PMID:26168749

  20. Effects of the chemical forms and valency states of neptunium on its jejunal transfer in the rat.

    PubMed

    Fritsch, P; Beauvallet, M; Jouniaux, B; Moutairou, K; Metivier, H; Masse, R

    1987-10-01

    The transfer of various Np(IV) and Np(V) chemical forms across the small intestine of rats was measured in instilled and perfused jejunum. Instillation of Np(V) nitrate together with citrate or DTPA resulted in the same absorption of Np as after instillation of Np(V) nitrate alone (3 per cent per hour). Perfusion of Np(V) nitrate with bicarbonate or DTPA resulted in a similar transfer (2 per cent) but added citrate or ascorbate resulted in reduced transfer (0.8 per cent). Addition of phytate reduced Np transfer in both instilled and perfused jejunum (0.4 per cent). Np(IV) transfer was usually the same as, or less than that of, the corresponding Np(V) forms. Np(IV) transfer was similar in perfused and instilled jejunum, increasing from 0.2 per cent in the presence of citrate and phytate, to 1 per cent with EDTA and DTPA. Except for phytate, all the forms of Np(V) tested behaved like Np(V) nitrate after transfer from the intestine or after intravenous injection. By contrast, the behaviour of Np(IV) varied for all the forms tested and, for a given form, varied as a function of the experimental procedure used, i.e. jejunal instillation, perfusion, or intravenous injection. These findings suggest that the intestinal transfer of Np might occur via the intercellular pathway, and that it is controlled by both the molecular weight of the Np compound and its stability constant.

  1. Rotation of cometary meteoroids

    NASA Astrophysics Data System (ADS)

    Čapek, D.

    2014-08-01

    Aims: The rotation of meteoroids caused by gas drag during the ejection from a cometary nucleus has not been studied yet. The aim of this study is to estimate the rotational characteristics of meteoroids after their release from a comet during normal activity. Methods: The basic dependence of spin rate on ejection velocity and meteoroid size is determined analytically. A sophisticated numerical model is then applied to meteoroids ejected from the 2P/Encke comet. The meteoroid shapes are approximated by polyhedrons, which have been determined by a 3D laser scanning method of 36 terrestrial rock samples. These samples come from three distinct sets with different origins and characteristics, such as surface roughness or angularity. Two types of gas-meteoroid interactions and three gas ejection models are assumed. The rotational characteristics of ejected meteoroid population are obtained by numerical integration of equations of motion with random initial conditions and random shape selection. Results: It is proved that the results do not depend on a specific set of shape models and that they are applicable to the (unknown) shapes of real meteoroids. A simple relationship between the median of meteoroid spin frequencies bar{f} (Hz), ejection velocities vej (m s-1), and sizes D (m) is determined. For diffuse reflection of gas molecules from meteoroid's surface it reads as bar{f≃ 2× 10-3 v_ej D-0.88}, and for specular reflection of gas molecules from meteoroid's surface it is bar{f≃ 5× 10-3 v_ej D-0.88}. The distribution of spin frequencies is roughly normal on log scale, and it is relatively wide: a 2σ-interval can be described as (0.1, 10)× bar{f}. Most of the meteoroids are non-principal axis rotators. The median angle between angular momentum vector and spin vector is 12°. About 60% of meteoroids rotate in long-axis mode. The distribution of angular momentum vectors is not random. They are concentrated in the perpendicular direction with respect to the gas

  2. Surgical Access to Jejunal Veins for Local Thrombolysis and Stent Placement in Portal Vein Thrombosis

    SciTech Connect

    Schellhammer, Frank; Esch, Jan Schulte am; Hammerschlag, Sascha; Knoefel, Wolfram Trudo; Fuerst, Guenter

    2008-07-15

    Portal vein thrombosis is an infrequent entity, which may cause high morbidity and mortality. We report a case of portal vein thrombosis due to benign stenosis following partial pancreatoduodenectomy with segmental replacement of the portal vein by a Gore-tex graft. Using a surgical access to jenunal veins, local thrombolysis, mechanical fragmentation of thrombus, and stent placement were successfully performed.

  3. DEVICE FOR CONVEYING AND ROTATING OBJECTS

    DOEpatents

    Frantz, C.E.; Roslund, J.

    1958-01-21

    A device is described for conveying cylindrical material with a combined rotary and axial motion. The material rides on a series of balls which are retained in a guide plate and rotated by bearing against a rotating drum. The drum has a series of conical sections or grooves cut in its outer surface on which the balls ride. The grooves and balls match in such a way that all the balls are caused to rotate about an axis at an angle to the drum axis. This skewed rotation of the ball imparts a longitudinal as well as a rotary motion to the cylinders being conveyed.

  4. Theoretical analysis of rotating cavitation in rocket pump inducers

    NASA Astrophysics Data System (ADS)

    Tsujimoto, Yoshinobu; Kamijo, Kenjiro; Yoshida, Yoshiki; Yoshida, Yoshiki

    1992-07-01

    Rotating cavitation was analyzed using an actuator disk method. Quasi-steady pressure performance of the impeller, mass flow gain factor and cavitation compliance of the cavity were taken into account. Three types of destabilizing modes were observed: rotating cavitation propagating faster than the rotational speed of the impeller, rotating cavitation propagating in the direction opposite that of the impeller, and rotating stall propagating slower than the rotational speed of the impeller. It was shown that both types of rotating cavitations were caused by the positive mass flow gain factor, while the rotating stall was caused by the positive slope of the pressure performance. Stability and propagation velocity maps are presented for the two types of rotating cavitations in the mass flow gain factor-cavitation compliance plane. The correlation between theoretical results and experimental observations is discussed.

  5. L-glutamine stimulates jejunal sodium and chloride absorption in pig rotavirus enteritis.

    PubMed

    Rhoads, J M; Keku, E O; Quinn, J; Woosely, J; Lecce, J G

    1991-03-01

    Rotavirus enteritis is the leading cause of diarrhea in infants worldwide. A research priority of the World Health Organization is to develop oral rehydration solutions containing amino acids or other additives that will stimulate intestinal absorption more efficiently than the current glucose-based oral rehydration solutions. Glutamine is the principal metabolic fuel of the small bowel and a putative stimulator of mucosal repair. This report describes the transport response to mucosal L-glutamine following intestinal injury caused by porcine rotavirus. Peak symptoms and mucosal damage were observed 2-7 days after oral rotavirus inoculation. In vitro transport studies of the maximally injured region, the midjejunum (80% reduction in lactase), surprisingly, showed transport responses to L-glutamine (30 mmol/L) and L-alanine (30 mmol/L) that were similar qualitatively and quantitatively to those observed in control tissue. Subsequent application of mucosal D-glucose (30 mmol/L) caused additional stimulation of electrogenic Na+ transport, but the response to glucose was blunted (P less than 0.05) in the infected tissues. Glutamine and alanine enhanced Na+ absorption to a similar degree (2-2.5 muEq.cm-2.h-1), but glutamine stimulated equal amounts of electrogenic and electroneutral NaCl absorption, whereas alanine had no significant effect on net Cl- flux. Glutamine is a potentially useful substrate for investigation in oral rehydration solutions for infant diarrhea.

  6. The Maximum Mass of Rotating Strange Stars

    NASA Astrophysics Data System (ADS)

    Szkudlarek, M.; Gondek-Rosiń; ska, D.; Villain, L.; Ansorg, M.

    2012-12-01

    Strange quark stars are considered as a possible alternative to neutron stars as compact objects (e.g. Weber 2003). A hot compact star (a proto-neutron star or a strange star) born in a supernova explosion or a remnant of neutron stars binary merger are expected to rotate differentially and be important sources of gravitational waves. We present results of the first relativistic calculations of differentially rotating strange quark stars for broad ranges of degree of differential rotation and maximum densities. Using a highly accurate, relativistic code we show that rotation may cause a significant increase of maximum allowed mass of strange stars, much larger than in the case of neutron stars with the same degree of differential rotation. Depending on the maximum allowed mass a massive neutron star (strange star) can be temporarily stabilized by differential rotation or collapse to a black hole.

  7. Rotational Preference in Gymnastics

    PubMed Central

    Heinen, Thomas; Jeraj, Damian; Vinken, Pia M.; Velentzas, Konstantinos

    2012-01-01

    In gymnastics, most skills incorporate rotations about one or more body axes. At present, the question remains open if factors such as lateral preference and/or vestibulo-spinal asymmetry are related to gymnast’s rotational preference. Therefore, we sought to explore relationships in gymnast’s rotation direction between different gymnastic skills. Furthermore, we sought to explore relationships between rotational preference, lateral preference, and vestibulo-spinal asymmetry. In the experiment n = 30 non-experts, n = 30 near-experts and n = 30 experts completed a rotational preference questionnaire, a lateral preference inventory, and the Unterberger-Fukuda Stepping Test. The results revealed, that near-experts and experts more often rotate rightward in the straight jump with a full turn when rotating leftward in the round-off and vice versa. The same relationship was found for experts when relating the rotation preference in the handstand with a full turn to the rotation preference in the straight jump with a full turn. Lateral preference was positively related to rotational preference in non-expert gymnasts, and vestibulo-spinal asymmetry was positively related to rotational preference in experts. We suggest, that gymnasts should explore their individual rotational preference by systematically practicing different skills with a different rotation direction, bearing in mind that a clearly developed structure in rotational preference between different skills may be appropriate to develop more complex skills in gymnastics. PMID:23486362

  8. Rotational preference in gymnastics.

    PubMed

    Heinen, Thomas; Jeraj, Damian; Vinken, Pia M; Velentzas, Konstantinos

    2012-06-01

    In gymnastics, most skills incorporate rotations about one or more body axes. At present, the question remains open if factors such as lateral preference and/or vestibulo-spinal asymmetry are related to gymnast's rotational preference. Therefore, we sought to explore relationships in gymnast's rotation direction between different gymnastic skills. Furthermore, we sought to explore relationships between rotational preference, lateral preference, and vestibulo-spinal asymmetry. In the experiment n = 30 non-experts, n = 30 near-experts and n = 30 experts completed a rotational preference questionnaire, a lateral preference inventory, and the Unterberger-Fukuda Stepping Test. The results revealed, that near-experts and experts more often rotate rightward in the straight jump with a full turn when rotating leftward in the round-off and vice versa. The same relationship was found for experts when relating the rotation preference in the handstand with a full turn to the rotation preference in the straight jump with a full turn. Lateral preference was positively related to rotational preference in non-expert gymnasts, and vestibulo-spinal asymmetry was positively related to rotational preference in experts. We suggest, that gymnasts should explore their individual rotational preference by systematically practicing different skills with a different rotation direction, bearing in mind that a clearly developed structure in rotational preference between different skills may be appropriate to develop more complex skills in gymnastics. PMID:23486362

  9. Effects of sleeve gastrectomy with jejuno-jejunal or jejuno-ileal loop on glycolipid metabolism in diabetic rats

    PubMed Central

    Zhong, Ming-Wei; Liu, Shao-Zhuang; Zhang, Guang-Yong; Zhang, Xiang; Hu, San-Yuan

    2016-01-01

    AIM To explore the effect of sleeve gastrectomy (SG) with jejuno-jejunal or jejuno-ileal loop on glycolipid metabolism in diabetic rats. METHODS Diabetic rats, which were induced by high-fat diet (HFD), nicotinamide and low-dose streptozotocin, underwent sham operations, SG, SG with jejuno-ileal loop (SG-JI) and SG with jejuno-jejunal loop (SG-JJ) followed by postoperative HFD. Then, at the time points of baseline and 2, 12 and 24 wk postoperatively, we determined and compared several variables, including the area under the curve for the results of oral glucose tolerance test (AUCOGTT), serum levels of triglyceride, cholesterol and ghrelin in fasting state, homeostasis model assessment of insulin resistance (HOMA-IR), body weight, calorie intake, glucagon-like peptide (GLP)-1 and insulin secretions after glucose gavage at dose of 1 g/kg. RESULTS At 2 wk postoperatively, rats that underwent SG, SG-JJ and SG-JI, compared with sham-operated (SHAM) rats, demonstrated lower body weight, calorie intake and ghrelin (P < 0.05 vs SHAM), enhanced secretion of insulin and GLP-1 after glucose gavage (P < 0.05 vs SHAM), improved AUCOGTT, HOMA-IR, fasting serum triglyceride and cholesterol (AUCOGTT: 1616.9 ± 83.2, 837.4 ± 83.7, 874.9 ± 97.2 and 812.6 ± 81.9, P < 0.05 vs SHAM; HOMA-IR: 4.31 ± 0.54, 2.94 ± 0.22, 3.17 ± 0.37 and 3.41 ± 0.22, P < 0.05 vs SHAM; Triglyceride: 2.35 ± 0.17, 1.87 ± 0.23, 1.98 ± 0.30 and 2.04 ± 0.21 mmol/L, P < 0.05 vs SHAM; Cholesterol: 1.84 ± 0.21, 1.53 ± 0.20, 1.52 ± 0.20 and 1.46 ± 0.23 mmol/L). At 12 wk postoperatively, rats receiving SG-JJ and SG-JI had lower body weight, reduced levels of triglyceride and cholesterol and elevated level of GLP-1 compared to those receiving SG (P < 0.05 vs SG). At 24 wk after surgery, compared with SG, the advantage of SG-JJ and SG-JI for glucolipid metabolism was still evident (P < 0.05 vs SG). SG-JI had a better performance in lipid metabolism and GLP-1 secretion of rats than did SG-JJ. CONCLUSION

  10. Effects of sleeve gastrectomy with jejuno-jejunal or jejuno-ileal loop on glycolipid metabolism in diabetic rats

    PubMed Central

    Zhong, Ming-Wei; Liu, Shao-Zhuang; Zhang, Guang-Yong; Zhang, Xiang; Hu, San-Yuan

    2016-01-01

    AIM To explore the effect of sleeve gastrectomy (SG) with jejuno-jejunal or jejuno-ileal loop on glycolipid metabolism in diabetic rats. METHODS Diabetic rats, which were induced by high-fat diet (HFD), nicotinamide and low-dose streptozotocin, underwent sham operations, SG, SG with jejuno-ileal loop (SG-JI) and SG with jejuno-jejunal loop (SG-JJ) followed by postoperative HFD. Then, at the time points of baseline and 2, 12 and 24 wk postoperatively, we determined and compared several variables, including the area under the curve for the results of oral glucose tolerance test (AUCOGTT), serum levels of triglyceride, cholesterol and ghrelin in fasting state, homeostasis model assessment of insulin resistance (HOMA-IR), body weight, calorie intake, glucagon-like peptide (GLP)-1 and insulin secretions after glucose gavage at dose of 1 g/kg. RESULTS At 2 wk postoperatively, rats that underwent SG, SG-JJ and SG-JI, compared with sham-operated (SHAM) rats, demonstrated lower body weight, calorie intake and ghrelin (P < 0.05 vs SHAM), enhanced secretion of insulin and GLP-1 after glucose gavage (P < 0.05 vs SHAM), improved AUCOGTT, HOMA-IR, fasting serum triglyceride and cholesterol (AUCOGTT: 1616.9 ± 83.2, 837.4 ± 83.7, 874.9 ± 97.2 and 812.6 ± 81.9, P < 0.05 vs SHAM; HOMA-IR: 4.31 ± 0.54, 2.94 ± 0.22, 3.17 ± 0.37 and 3.41 ± 0.22, P < 0.05 vs SHAM; Triglyceride: 2.35 ± 0.17, 1.87 ± 0.23, 1.98 ± 0.30 and 2.04 ± 0.21 mmol/L, P < 0.05 vs SHAM; Cholesterol: 1.84 ± 0.21, 1.53 ± 0.20, 1.52 ± 0.20 and 1.46 ± 0.23 mmol/L). At 12 wk postoperatively, rats receiving SG-JJ and SG-JI had lower body weight, reduced levels of triglyceride and cholesterol and elevated level of GLP-1 compared to those receiving SG (P < 0.05 vs SG). At 24 wk after surgery, compared with SG, the advantage of SG-JJ and SG-JI for glucolipid metabolism was still evident (P < 0.05 vs SG). SG-JI had a better performance in lipid metabolism and GLP-1 secretion of rats than did SG-JJ. CONCLUSION

  11. PLT rotating pumped limiter

    SciTech Connect

    Cohen, S.A.; Budny, R.V.; Corso, V.; Boychuck, J.; Grisham, L.; Heifetz, D.; Hosea, J.; Luyber, S.; Loprest, P.; Manos, D.

    1984-07-01

    A limiter with a specially contoured front face and the ability to rotate during tokamak discharges has been installed in a PLT pump duct. These features have been selected to handle the unique particle removal and heat load requirements of ICRF heating and lower-hybrid current-drive experiments. The limiter has been conditioned and commissioned in an ion-beam test stand by irradiation with 1 MW power, 200 ms duration beams of 40 keV hydrogen ions. Operation in PLT during ohmic discharges has proven the ability of the limiter to reduce localized heating caused by energetic electron bombardment and to remove about 2% of the ions lost to the PLT walls and limiters.

  12. Effect of dietary fatty acids on jejunal and ileal oleic acid uptake by rat brush border membrane vesicles.

    PubMed

    Prieto, R M; Stremmel, W; Sales, C; Tur, J A

    1996-04-18

    To test the effect of dietary fatty acids on fatty acid uptake, the influx kinetics of a representative long-chain fatty acid, 3H-oleic acid, in both the jejunum and ileum of rats has been studied using brush border membrane vesicles (BBMV). Animals were fed with semipurified diets containing 5 g fat/100 g diet, as corn oil (control group), safflower oil (unsaturated group) and coconut oil hydrogenated (saturated group). With increasing unbound oleate concentration in the medium, the three dietary groups showed saturable kinetics in both jejunal and ileal BBMV (controls: Vmax = 0.15 +/- 0.01 nmol x mg protein-1 x 5 min-1 and Km = 136 +/- 29.1 nmol for jejunum, and Vmax = 0.23 +/- 0.03 nmol x mg protein-1 x 5 min-1 and Km = 196 +/- 50.3 nmol for ileum; unsaturated: Vmax = 0.28 +/- 0.05 nmol x mg protein-1 x 5 min-1 and Km = 242.7 +/- 91.8 nmol for jejunum, and Vmax = 1.29 +/- 0.06 nmol x mg protein-1 x 5 min-1 and Km = 509.8 +/- 97.5 nmol for ileum; saturated: Vmax = 0.03 +/- 0.01 nmol x mg protein-1 x 5 min-1 and Km = 124.5 +/- 72.6 nmol for jejunum, and Vmax = 0.04 +/- 0.01 nmol x mg protein -1.5 min-1 and Km = 205.6 +/- 85.3 nmol for ileum). These results support the theory that feeding an isocaloric diet containing only unsaturated fatty acids enhanced oleic acid uptake, and feeding an isocaloric diet containing only saturated fatty acids decreased oleic acid uptake. The results obtained in the present work also show the adaptative ability of jejunum and ileum to the type of dietary fat.

  13. Intestinal adaptation and Reg gene expression induced by antidiabetic duodenal-jejunal bypass surgery in Zucker fatty rats.

    PubMed

    Li, Bing; Lu, Yarong; Srikant, Coimbatore B; Gao, Zu-Hua; Liu, Jun-Li

    2013-04-01

    The antidiabetic mechanism of bariatric surgery includes specific changes in the secretion of incretins. To identify additional players originating from the gut, we evaluated the effects of duodenal-jejunal bypass (DJB) in morbidly obese Zucker fatty rats. A fast relief of hyperglycemia and hyperinsulinemia was achieved even before a significant weight loss occurred. Fourteen days after DJB, we characterized the changes in intestinal histochemistry in the bypassed duodenum and shortcut jejunum that was reanastomosed directly to the starting point of the duodenum and compared with the corresponding regions of sham-operated rats. The bypassed duodenum exhibited mucosal atrophy and apoptosis and decreased proliferative renewal. In shortcut jejunum, DJB resulted in 40% significantly enlarged intestinal circumference and increased epithelial proliferation, especially in putative transit-amplifying (TA) cells and the crypt. Because Reg family proteins promote cell growth and survival, we explored their expression in the intestine. With the use of immunohistochemistry, Reg1, -3α, and -3β were normally expressed in intestinal mucosa. After DJB, the level of Reg1 protein was reduced, whereas Reg3α and -3β were not changed in bypassed duodenum. Downstream in shortcut jejunum, the levels of Reg1 and -3β were greatly induced and especially concentrated in the putative TA cells. Our results revealed significant changes in the integrity and proliferation of the intestinal mucosa as a consequence of DJB, and in cell- and isoform-specific expression of Reg proteins within the replicating mucosal epithelium, and provide evidence indicating that the activation of Reg proteins may contribute to intestinal compensation against increased load and/or to improving insulin sensitivity.

  14. miR-200a regulates Rheb-mediated amelioration of insulin resistance after duodenal–jejunal bypass

    PubMed Central

    Guo, W; Han, H; Wang, Y; Zhang, X; Liu, S; Zhang, G; Hu, S

    2016-01-01

    Objectives: Duodenal–jejunal bypass (DJB) surgery can induce the rapid and durable remission of diabetes. Recent studies indicate that ameliorated hepatic insulin resistance and improved insulin signaling might contribute to the diabetic control observed after DJB. Ras homolog enriched in brain (Rheb) is reported to have an important role in insulin pathway, and some microRNAs (miRNAs) have been found to regulate Rheb. This study was conducted to investigate the effects of DJB on hepatic insulin resistance and the effects of miRNA-200a, a Rheb-targeting miRNA, on the development of DJB-induced amelioration in hepatic insulin resistance. Subjects: We investigated hepatic insulin signaling change and mapped the hepatic miRNAome involved in a rat model of DJB. We studied the effects of miR-200a on Rheb signaling pathway in buffalo rat liver cell lines. Liver tissues were studied and glucose tolerance tests were conducted in DJB rats injected with lentivirus encoding miR-200a inhibitor and diabetic rats injected with miR-200a mimic. Results: Rheb is a potential target of miR-200a. Transfection with an miR-200a inhibitor increased Rheb protein levels and enhanced the feedback action on insulin receptor substrate-dependent insulin signaling, whereas transfection with an miR-200a mimic produced the opposite effects. A luciferase assay confirmed that miR-200a bind to the 3′UTR (untranslated regions) of Rheb. Global downregulation of miR-200a in DJB rats showed impaired insulin sensitivity whereas upregulation of miR-200a in diabetic rats showed amelioration of diabetes. Conclusions: A novel mechanism was identified, in which miR-200a regulates the Rheb-mediated amelioration of insulin resistance in DJB. The findings suggest miR-200a should be further explored as a potential target for the treatment of diabetes. PMID:27121251

  15. Error correction for rotationally asymmetric surface deviation testing based on rotational shears.

    PubMed

    Wang, Weibo; Liu, Pengfei; Xing, Yaolong; Tan, Jiubin; Liu, Jian

    2016-09-10

    We present a practical method for absolute testing of rotationally asymmetric surface deviation based on rotation averaging, additional compensation, and azimuthal errors correction. The errors of angular orders kNθ neglected in the traditional multiangle averaging method can be reconstructed and compensated with the help of least-squares fitting of Zernike polynomials by an additional rotation measurement with a suitable selection of rotation angles. The estimation algorithm adopts the least-squares technique to eliminate azimuthal errors caused by rotation inaccuracy. The unknown relative alignment of the measurements also can be estimated through the differences in measurement results at overlapping areas. The method proposed combines the advantages of the single-rotation and multiangle averaging methods and realizes a balance between the efficiency and accuracy of the measurements. Experimental results show that the method proposed can obtain high accuracy even with fewer rotation measurements. PMID:27661385

  16. Power Harvesting from Rotation?

    ERIC Educational Resources Information Center

    Chicone, Carmen; Feng, Z. C.

    2008-01-01

    We show the impossibility of harvesting power from rotational motions by devices attached to the rotating object. The presentation is suitable for students who have studied Lagrangian mechanics. (Contains 2 figures.)

  17. Rotator cuff problems

    MedlinePlus

    ... rotator cuff is a group of muscles and tendons that attach to the bones of the shoulder ... Rotator cuff tendinitis refers to irritation of these tendons and inflammation of the bursa (a normally smooth ...

  18. Asymmetric error field interaction with rotating conducting walls

    SciTech Connect

    Paz-Soldan, C.; Brookhart, M. I.; Hegna, C. C.; Forest, C. B.

    2012-07-15

    The interaction of error fields with a system of differentially rotating conducting walls is studied analytically and compared to experimental data. Wall rotation causes eddy currents to persist indefinitely, attenuating and rotating the original error field. Superposition of error fields from external coils and plasma currents are found to break the symmetry in wall rotation direction. The vacuum and plasma eigenmodes are modified by wall rotation, with the error field penetration time decreased and the kink instability stabilized, respectively. Wall rotation is also predicted to reduce error field amplification by the marginally stable plasma.

  19. Rotations with Rodrigues' Vector

    ERIC Educational Resources Information Center

    Pina, E.

    2011-01-01

    The rotational dynamics was studied from the point of view of Rodrigues' vector. This vector is defined here by its connection with other forms of parametrization of the rotation matrix. The rotation matrix was expressed in terms of this vector. The angular velocity was computed using the components of Rodrigues' vector as coordinates. It appears…

  20. Broad early immune response of porcine epithelial jejunal IPI-2I cells to Entamoeba histolytica.

    PubMed

    Meurens, François; Girard-Misguich, Fabienne; Melo, Sandrine; Grave, Aurore; Salmon, Henri; Guillén, Nancy

    2009-02-01

    Amoebiasis caused by Entamoebahistolytica triggers an acute inflammatory response at early stages of intestinal infection. The patho-physiological study of intestinal amoebiasis requires the development of powerful animal models. Swine provide robust model for human diseases and they could be used to study intestinal amoebiasis. Here, we introduce an in vitro model of swine intestinal epithelial cell (IPI-2I) co-cultured with E. histolytica. Intestinal epithelial cells (IECs) have crucial roles in sensing pathogens and initiating innate immune response, which qualitatively influence adaptive immune response against them. The contact between the two cells induces marked macroscopic lesions of IEC monolayer and striking alteration of the IPI-2I cell phenotype including blebbing, such as loss of attachment before to be phagocyte by the trophozoite. Increase in Lactate Dehydrogenase (LDH) levels in the culture supernatant of IECs was observed when ameba is present and could reflect the cellular cytotoxicity exerted by the parasite. Using quantitative real-time PCR, we identified the up-regulation of cytokines/chemokines implicated in neutrophil chemoattraction and inflammation, such as CCL2, CCL20, CXCL2, CXCL3, GM-CSF, IL1 alpha, IL6 and IL8, in response to the parasite that can further regulate the immunoregulatory functions of the immune cells of the host. The study points a cardinal role of these pro-inflammatory compounds as central mediators in the interaction IECs/ameba and suggests mechanisms by which they coordinate intestinal immune response. This will focus future efforts on delineating the molecular and cellular mechanisms of other cell partners by the way of in vivo infection of swine.

  1. Progress in geophysical aspects of the rotation of the earth

    NASA Technical Reports Server (NTRS)

    Lambeck, K.

    1978-01-01

    The geophysical causes and consequences of the Earth's rotation are reviewed. Specific topics covered include: (1) the motion of the rotation axis in space, precession and nutation; (2) the motion of the rotation axis relative to the Earth, polar motion; and (3) the rate of rotation about this axis, or changes in the length of day. Secular decrease in obliquity and evolution of the Earth-Moon system are also discussed.

  2. SEAL FOR ROTATING SHAFT

    DOEpatents

    Coffman, R.T.

    1957-12-10

    A seal is described for a rotatable shaft that must highly effective when the shaft is not rotating but may be less effective while the shaft is rotating. Weights distributed about a sealing disk secured to the shaft press the sealing disk against a tubular section into which the shiilt extends, and whem the shaft rotates, the centrifugal forces on the weights relieve the pressurc of the sealing disk against the tubular section. This action has the very desirible result of minimizing the wear of the rotating disk due to contact with the tubular section, while affording maximum sealing action when it is needed.

  3. Predictors of human rotation.

    PubMed

    Stochl, Jan; Croudace, Tim

    2013-01-01

    Why some humans prefer to rotate clockwise rather than anticlockwise is not well understood. This study aims to identify the predictors of the preferred rotation direction in humans. The variables hypothesised to influence rotation preference include handedness, footedness, sex, brain hemisphere lateralisation, and the Coriolis effect (which results from geospatial location on the Earth). An online questionnaire allowed us to analyse data from 1526 respondents in 97 countries. Factor analysis showed that the direction of rotation should be studied separately for local and global movements. Handedness, footedness, and the item hypothesised to measure brain hemisphere lateralisation are predictors of rotation direction for both global and local movements. Sex is a predictor of the direction of global rotation movements but not local ones, and both sexes tend to rotate clockwise. Geospatial location does not predict the preferred direction of rotation. Our study confirms previous findings concerning the influence of handedness, footedness, and sex on human rotation; our study also provides new insight into the underlying structure of human rotation movements and excludes the Coriolis effect as a predictor of rotation.

  4. Rotated balance in humans due to repetitive rotational movement

    NASA Astrophysics Data System (ADS)

    Zakynthinaki, M. S.; Madera Milla, J.; López Diaz De Durana, A.; Cordente Martínez, C. A.; Rodríguez Romo, G.; Sillero Quintana, M.; Sampedro Molinuevo, J.

    2010-03-01

    We show how asymmetries in the movement patterns during the process of regaining balance after perturbation from quiet stance can be modeled by a set of coupled vector fields for the derivative with respect to time of the angles between the resultant ground reaction forces and the vertical in the anteroposterior and mediolateral directions. In our model, which is an adaption of the model of Stirling and Zakynthinaki (2004), the critical curve, defining the set of maximum angles one can lean to and still correct to regain balance, can be rotated and skewed so as to model the effects of a repetitive training of a rotational movement pattern. For the purposes of our study a rotation and a skew matrix is applied to the critical curve of the model. We present here a linear stability analysis of the modified model, as well as a fit of the model to experimental data of two characteristic "asymmetric" elite athletes and to a "symmetric" elite athlete for comparison. The new adapted model has many uses not just in sport but also in rehabilitation, as many work place injuries are caused by excessive repetition of unaligned and rotational movement patterns.

  5. Effect of genistein on basal jejunal chloride secretion in R117H CF mice is sex and route specific.

    PubMed

    Rayyan, Esa; Polito, Sarah; Leung, Lana; Bhakta, Ashesh; Kang, Jonathan; Willey, Justin; Mansour, Wasim; Drumm, Mitchell L; Al-Nakkash, Layla

    2015-01-01

    Cystic fibrosis (CF) results from the loss or reduction in function of the CFTR (cystic fibrosis transmembrane conductance regulatory protein) chloride channel. The third most common CFTR mutation seen clinically is R117H. Genistein, a naturally occurring phytoestrogen, is known to stimulate CFTR function in vitro. We aimed to determine whether route of administration of genistein could mediate differential effects in R117H male and female CF mice. Mice were fed (4 weeks) or injected subcutaneously (1 week) with the following: genistein 600 mg/kg diet (600Gd); genistein-free diet (0Gd); genistein injection 600 mg/kg body weight (600Gi); dimethyl sulfoxide control (0Gi). In male R117H mice fed 600Gd, basal short circuit current (Isc) was unchanged. In 600Gd-fed female mice, there was a subgroup that demonstrated a significant increase in basal Isc (53.14±7.92 μA/cm(2), n=6, P<0.05) and a subgroup of nonresponders (12.05±6.59 μA/cm(2), n=4), compared to 0Gd controls (29.3±6.5 μA/cm(2), n=7). In R117H mice injected with 600Gi, basal Isc was unchanged in both male and female mice compared to 0Gi controls. Isc was measured in response to the following: the adenylate cyclase activator forskolin (10 μM, bilateral), bumetanide (100 μM, basolateral) to indicate the Cl(-) secretory component, and acetazolamide (100 μM, bilateral) to indicate the HCO3 (-) secretory component; however, there was no effect of genistein (diet or injection) on any of these parameters. Jejunal morphology (ie, villi length, number of goblet cells per villus, crypt depth, and number of goblet cells per crypt) in R117H mice suggested no genistein-mediated difference among the groups. Serum levels of genistein were significantly elevated, compared to respective controls, by either 600Gd (equally elevated in males and females) or 600Gi (elevated more in females versus males). These data suggest a sex-dependent increase in basal Isc of R117H mice and that the increase is also specific for route

  6. Partial Thickness Rotator Cuff Tears: Current Concepts

    PubMed Central

    Matthewson, Graeme; Beach, Cara J.; Nelson, Atiba A.; Woodmass, Jarret M.; Ono, Yohei; Boorman, Richard S.; Lo, Ian K. Y.; Thornton, Gail M.

    2015-01-01

    Partial thickness rotator cuff tears are a common cause of pain in the adult shoulder. Despite their high prevalence, the diagnosis and treatment of partial thickness rotator cuff tears remains controversial. While recent studies have helped to elucidate the anatomy and natural history of disease progression, the optimal treatment, both nonoperative and operative, is unclear. Although the advent of arthroscopy has improved the accuracy of the diagnosis of partial thickness rotator cuff tears, the number of surgical techniques used to repair these tears has also increased. While multiple repair techniques have been described, there is currently no significant clinical evidence supporting more complex surgical techniques over standard rotator cuff repair. Further research is required to determine the clinical indications for surgical and nonsurgical management, when formal rotator cuff repair is specifically indicated and when biologic adjunctive therapy may be utilized. PMID:26171251

  7. Intussusception causing postoperative intestinal obstruction following free jejunum transfer in adults: two case reports and review of the literature.

    PubMed

    Matsumoto, Akira; Watanabe, Masayuki; Shigaki, Hironobu; Okumura, Yasuhiro; Nishida, Koujiro; Mine, Shinji; Yamada, Kazuhiko; Yanaga, Katsuhiko; Sano, Takeshi

    2015-12-01

    Intussusception is a rare cause of postoperative intestinal obstruction in adults. We experienced two cases of bowel obstruction due to the jejuno-jejunal intussusception after harvest of a free jejunum graft for reconstruction after cervical esophagectomy. Bowel obstruction occurred early in the postoperative course, and reoperations were needed in both cases. In both case, the anastomotic site was resected and re-anastomosed in a side-to-side fashion. Recurrence of intussusception has not been observed. In the literature, such a complication has been documented in two case series and a case report. The reported incidence of postoperative intussusception of the case series was 2.8% and 7.4%, respectively. The jejuno-jejunal anastomoses were performed with end-to-end fashion by two layered hand-sewn suture (Albert-Lembert method) in all cases reported. In order to prevent the occurrence of postoperative intussusception, we recommend to harvest a free jejunal graft as far from the Treitz ligament as possible and to avoid reconstruction by an Albert-Lembert end-to-end anastomosis. PMID:26943396

  8. Rotating saddle trap as Foucault's pendulum

    NASA Astrophysics Data System (ADS)

    Kirillov, Oleg N.; Levi, Mark

    2016-01-01

    One of the many surprising results found in the mechanics of rotating systems is the stabilization of a particle in a rapidly rotating planar saddle potential. Besides the counterintuitive stabilization, an unexpected precessional motion is observed. In this note, we show that this precession is due to a Coriolis-like force caused by the rotation of the potential. To our knowledge, this is the first example where such a force arises in an inertial reference frame. We also propose a simple mechanical demonstration of this effect.

  9. Global Rotation of Non-Rotating Origin

    NASA Astrophysics Data System (ADS)

    Fukushima, T.

    2001-11-01

    At its 24th General Assembly held at Manchester last year, the IAU has adopted the Celestial Ephemeris Origin (CEO) as a new longitude origin of the celestial coordinate system (Capitaine et al. 2000, IAU 2001). The CEO is the application of Guinot's non-rotating origin (NRO) to the Earth's equator (Guinot 1979, Capitaine et al. 1986, Capitaine 1990). By using the current IAU precession/nutation theory, we integrated the global orbit of CEO. It is a slightly curved zigzag pattern of the amplitude of around 23o moving secularly along the ecliptic. Among its kinematical features, we note that CEO has a large secular component of rotation with respect to the inertial reference frame. The current speed of this global rotation is as large as around -4.15 ''/yr. The negative sign shows that CEO rotates clockwise with respect to the inertial frame when viewed from the north celestial pole. Unfortunately this is a general property of NROs. On the other hand, such secular rotation does not exist for some geometrically-defined longitude origins like K, H, and Σ already discussed in Kovalevsky and McCarthy (1998). We think that the existence of a global secular rotaion means that the CEO, and NROs in general, is not appropriate to be specified as the x-axis of celestial coordinate systems.

  10. Central Rotations of Milky Way Globular Clusters

    NASA Astrophysics Data System (ADS)

    Fabricius, Maximilian H.; Noyola, Eva; Rukdee, Surangkhana; Saglia, Roberto P.; Bender, Ralf; Hopp, Ulrich; Thomas, Jens; Opitsch, Michael; Williams, Michael J.

    2014-06-01

    Most Milky Way globular clusters (GCs) exhibit measurable flattening, even if on a very low level. Both cluster rotation and tidal fields are thought to cause this flattening. Nevertheless, rotation has only been confirmed in a handful of GCs, based mostly on individual radial velocities at large radii. We are conducting a survey of the central kinematics of Galactic GCs using the new Integral Field Unit instrument VIRUS-W. We detect rotation in all 11 GCs that we have observed so far, rendering it likely that a large majority of the Milky Way GCs rotate. We use published catalogs of GCs to derive central ellipticities and position angles. We show that in all cases where the central ellipticity permits an accurate measurement of the position angle, those angles are in excellent agreement with the kinematic position angles that we derive from the VIRUS-W velocity fields. We find an unexpected tight correlation between central rotation and outer ellipticity, indicating that rotation drives flattening for the objects in our sample. We also find a tight correlation between central rotation and published values for the central velocity dispersion, most likely due to rotation impacting the old dispersion measurements. This Letter includes data taken at The McDonald Observatory of The University of Texas at Austin.

  11. CENTRAL ROTATIONS OF MILKY WAY GLOBULAR CLUSTERS

    SciTech Connect

    Fabricius, Maximilian H.; Rukdee, Surangkhana; Saglia, Roberto P.; Bender, Ralf; Hopp, Ulrich; Thomas, Jens; Williams, Michael J.; Noyola, Eva; Opitsch, Michael

    2014-06-01

    Most Milky Way globular clusters (GCs) exhibit measurable flattening, even if on a very low level. Both cluster rotation and tidal fields are thought to cause this flattening. Nevertheless, rotation has only been confirmed in a handful of GCs, based mostly on individual radial velocities at large radii. We are conducting a survey of the central kinematics of Galactic GCs using the new Integral Field Unit instrument VIRUS-W. We detect rotation in all 11 GCs that we have observed so far, rendering it likely that a large majority of the Milky Way GCs rotate. We use published catalogs of GCs to derive central ellipticities and position angles. We show that in all cases where the central ellipticity permits an accurate measurement of the position angle, those angles are in excellent agreement with the kinematic position angles that we derive from the VIRUS-W velocity fields. We find an unexpected tight correlation between central rotation and outer ellipticity, indicating that rotation drives flattening for the objects in our sample. We also find a tight correlation between central rotation and published values for the central velocity dispersion, most likely due to rotation impacting the old dispersion measurements.

  12. Hematological and serum biochemical parameters of blood in adolescent rats and histomorphological changes in the jejunal epithelium and liver after chronic exposure to cadmium and lead in the case of supplementation with green tea vs black, red or white tea.

    PubMed

    Tomaszewska, Ewa; Winiarska-Mieczan, Anna; Dobrowolski, Piotr

    2015-01-01

    Rats were used to check whether regular consumption of black, red, or white tea would have a protective effect similar to the action of green tea on the intestine and liver in the case of exposure to Cd and Pb within the limits of human environmental exposure to these elements. Rats at the age of 6 weeks were divided into the control and four groups supplemented with green (GT), black (BT), red (RT), or white (WT) tea extracts. Their diet (except the control) was mixed with 7 mg Cd/kg and 50mg Pb/kg. The experiment lasted 12 weeks. The effects of administration of tea in Cd- and Pb-poisoned rats on plasma biochemical parameters and the jejunal epithelium and liver were determined. The highest body mass was found in the GT group. The highest hemoglobin and Fe concentrations were in the control and GT groups. The highest activity of AST was in groups poisoned with Cd and Pb independently on supplementation. The highest ALT activity was in BT and RT groups with lower content of polifenoles. Pb and Cd disturbed the liver leading to necrosis and fatty degenerative changes, and a loss of normal architecture of the hepatocytes. Rats from the GT group had the highest cell proliferation rate in intestinal glands and the largest absorptive surface. Black, red, and white tea exerted a varied impact on the histological structure and innervation of the small intestine wall as well as on the absorptive function of small intestine mucosa in rats poisoned with Pb and Cd than green tea. On the other hand, taking into account the number of apoptotic cells, the effect of the teas was the same. Moreover, it is clear that long term exposure to Cd and Pb contamination causes toxic effect in the liver.

  13. Asteroid rotation rates

    NASA Technical Reports Server (NTRS)

    Dermott, S. F.; Harris, A. W.; Murray, C. D.

    1984-01-01

    A trend of increasing mean rotational frequency with increasing diameter is noted in asteroids with diameters greater than 120 km, irrespective of M-, S-, and C-type asteroid subset and family or nonfamily membership. This trend cannot be accounted for by observational selection. For asteroids with diameters smaller than 120 km mean rotational frequency increases with decreasing diameter, but within this group there is a subset with exceptionally long rotational periods. This marked change in the distribution at 120-km diameter could separate primordial asteroids from their collision products. It is also noted that, for asteroids of a given diameter, M asteroids rotate faster than S asteroids, which in turn rotate faster than C asteroids. For all types, family members rotate faster than nonfamily members.

  14. The spatial rotator.

    PubMed

    Rasmusson, A; Hahn, U; Larsen, J O; Gundersen, H J G; Jensen, E B Vedel; Nyengaard, J R

    2013-05-01

    This paper presents a new local volume estimator, the spatial rotator, which is based on measurements on a virtual 3D probe, using computer assisted microscopy. The basic design of the probe builds upon the rotator principle which requires only a few manual intersection markings, thus making the spatial rotator fast to use. Since a 3D probe is involved, it is expected that the spatial rotator will be more efficient than the the nucleator and the planar rotator, which are based on measurements in a single plane. An extensive simulation study shows that the spatial rotator may be more efficient than the traditional local volume estimators. Furthermore, the spatial rotator can be seen as a further development of the Cavalieri estimator, which does not require randomization of sectioning or viewing direction. The tissue may thus be sectioned in any arbitrary direction, making it easy to identify the specific tissue region under study. In order to use the spatial rotator in practice, however, it is necessary to be able to identify intersection points between cell boundaries and test rays in a series of parallel focal planes, also at the peripheral parts of the cell boundaries. In cases where over- and underprojection phenomena are not negligible, they should therefore be corrected for if the spatial rotator is to be applied. If such a correction is not possible, it is needed to avoid these phenomena by using microscopy with increased resolution in the focal plane. PMID:23488880

  15. Centrifugally activated bearing for high-speed rotating machinery

    DOEpatents

    Post, Richard F.

    1994-01-01

    A centrifugally activated bearing is disclosed. The bearing includes an annular member that extends laterally and radially from a central axis. A rotating member that rotates about the central axis relative to the annular member is also included. The rotating member has an interior chamber that surrounds the central axis and in which the annular member is suspended. Furthermore, the interior chamber has a concave shape for retaining a lubricant therein while the rotating member is at rest and for retaining a lubricant therein while the rotating member is rotating. The concave shape is such that while the rotating member is rotating a centrifugal force causes a lubricant to be forced away from the central axis to form a cylindrical surface having an axis collinear with the central axis. This centrifugally displaced lubricant provides restoring forces to counteract lateral displacement during operation.

  16. Rotation of Nonspherical Particles in Turbulent Channel Flow.

    PubMed

    Zhao, Lihao; Challabotla, Niranjan Reddy; Andersson, Helge I; Variano, Evan A

    2015-12-11

    The effects of particle inertia, particle shape, and fluid shear on particle rotation are examined using direct numerical simulation of turbulent channel flow. Particles at the channel center (nearly isotropic turbulence) and near the wall (highly sheared flow) show different rotation patterns and surprisingly different effects of particle inertia. Oblate particles at the center tend to rotate orthogonally to their symmetry axes, whereas prolate particles rotate around their symmetry axes. This trend is weakened by increasing inertia so that highly inertial oblate spheroids rotate nearly isotropically about their principle axes at the channel center. Near the walls, inertia does not move the rotation of spheroids towards isotropy but, rather, reverses the trend, causing oblate spheroids to rotate strongly about their symmetry axes and prolate spheroids to rotate normal to their symmetry axes. The observed phenomena are mostly ascribed to preferential orientations of the spheroids.

  17. Centrifugally activated bearing for high-speed rotating machinery

    DOEpatents

    Post, R.F.

    1994-02-15

    A centrifugally activated bearing is disclosed. The bearing includes an annular member that extends laterally and radially from a central axis. A rotating member that rotates about the central axis relative to the annular member is also included. The rotating member has an interior chamber that surrounds the central axis and in which the annular member is suspended. Furthermore, the interior chamber has a concave shape for retaining a lubricant therein while the rotating member is at rest and for retaining a lubricant therein while the rotating member is rotating. The concave shape is such that while the rotating member is rotating a centrifugal force causes a lubricant to be forced away from the central axis to form a cylindrical surface having an axis collinear with the central axis. This centrifugally displaced lubricant provides restoring forces to counteract lateral displacement during operation. 4 figures.

  18. Rotational effects on impingement cooling

    NASA Astrophysics Data System (ADS)

    Epstein, A. H.; Kerrebrock, J. L.; Koo, J. J.; Preiser, U. Z.

    The present consideration of rotation effects on heat transfer in a radially exhausted, impingement-cooled turbine blade model gives attention to experimental results for Reynolds and Rossby numbers and blade/coolant temperature ratio values that are representative of small gas turbine engines. On the basis of a model that encompasses the effects of Coriolis force and buoyancy on heat transfer, bouyancy is identified as the cause of an average Nusselt number that is 20-30 percent lower than expected from previous nonrotating data. A heuristic model is proposed which predicts that the impingement jets nearest the blade roots should deflect inward, due to a centripetal force generated by their tangential velocity counter to the blade motion. Potentially serious thermal stresses must be anticipated from rotation effects in the course of blade design.

  19. Alterations in gut microbiota during remission and recurrence of diabetes after duodenal-jejunal bypass in rats

    PubMed Central

    Zhong, Ming-Wei; Liu, Shao-Zhuang; Zhang, Guang-Yong; Zhang, Xiang; Liu, Teng; Hu, San-Yuan

    2016-01-01

    AIM: To observe the alterations in gut microbiota in high-fat diet (HFD)-induced diabetes recurrence after duodenal-jejunal bypass (DJB) in rats. METHODS: We assigned HDF- and low-dose streptozotocin-induced diabetic rats into two major groups to receive DJB and sham operation respectively. When the DJB was completed, we used HFD to induce diabetes recurrence. Then, we grouped the DJB-operated rats by blood glucose level into the DJB-remission (DJB-RM) group and the DJB-recurrence (DJB-RC) group. At a sequence of time points after operations, we compared calorie content in the food intake (calorie intake), oral glucose tolerance test, homeostasis model assessment of insulin resistance (HOMA-IR), concentrations of glucagon-like peptide 1 (GLP-1), serum insulin, total bile acids (TBAs) and lipopolysaccharide (LPS) and alterations in colonic microbiota. RESULTS: The relative abundance of Firmicutes in the control (58.06% ± 11.12%; P < 0.05 vs sham; P < 0.05 vs DJB-RC) and DJB-RM (55.58% ± 6.16%; P < 0.05 vs sham; P < 0.05 vs DJB-RC) groups was higher than that in the sham (29.04% ± 1.36%) and DJB-RC (27.44% ± 2.17%) groups; but the relative abundance of Bacteroidetes was lower (control group: 33.46% ± 10.52%, P < 0.05 vs sham 46.88% ± 2.34%, P < 0.05 vs DJB-RC 47.41% ± 5.67%. DJB-RM group: 34.63% ± 3.37%, P < 0.05 vs sham; P < 0.05 vs DJB-RC). Escherichia coli was higher in the sham (15.72% ± 1.67%, P < 0.05 vs control, P < 0.05 vs DJB-RM) and DJB-RC (16.42% ± 3.00%; P < 0.05 vs control; P < 0.05 vs DJB-RM) groups than in the control (3.58% ± 3.67%) and DJB-RM (4.15% ± 2.76%) groups. Improved HOMA-IR (2.82 ± 0.73, P < 0.05 vs DJB-RC 4.23 ± 0.72), increased TBAs (27803.17 ± 4673.42 ng/mL; P < 0.05 vs DJB-RC 18744.00 ± 3047.26 ng/mL) and decreased LPS (0.12 ± 0.04 ng/mL, P < 0.05 vs DJB-RC 0.19 ± 0.03 ng/mL) were observed the in DJB-RM group; however, these improvements were reversed in the DJB-RC group, with the exception of GLP-1 (DJB-RM vs DJB-RC P

  20. Rotator cuff injuries in adolescent athletes.

    PubMed

    Weiss, Jennifer M; Arkader, Alexandre; Wells, Lawrence M; Ganley, Theodore J

    2013-03-01

    The cause of rotator cuff injuries in the young athlete has been described as an overuse injury related to internal impingement. Abduction coupled with external rotation is believed to impinge on the rotator cuff, specifically the supraspinatus, and lead to undersurface tears that can progress to full-thickness tears. This impingement is believed to be worsened with increased range of motion and instability in overhead athletes. A retrospective review of seven patients diagnosed with rotator cuff injuries was performed to better understand this shoulder injury pattern. The type of sport played, a history of trauma, diagnosis, treatment method, and outcome were noted. Six patients were male and one was a female. Baseball was the primary sport for four patients, basketball for one, gymnastics for one, and wrestling for one. The following injury patterns were observed: two patients tore their subscapularis tendon, two sustained avulsion fractures of their lesser tuberosity, one tore his rotator interval, one tore his supraspinatus, and one avulsed his greater tuberosity. Only four patients recalled a specific traumatic event. Three patients were treated with arthroscopic rotator cuff repair, three with miniopen repair, and one was treated with rehabilitation. Six of the seven patients returned to their preinjury level of sport after treatment. Rotator cuff tears are rare in the adolescent age group. The injury patterns suggest that acute trauma likely accounts for many rotator cuff tears and their equivalents in the young patient. Adolescents with rotator cuff tears reliably return to sports after treatment. The possibility of rotator cuff tears in skeletally immature athletes should be considered. The prognosis is very good once this injury is identified and treated. PMID:22668571

  1. Rotator cuff injuries in adolescent athletes.

    PubMed

    Weiss, Jennifer M; Arkader, Alexandre; Wells, Lawrence M; Ganley, Theodore J

    2013-03-01

    The cause of rotator cuff injuries in the young athlete has been described as an overuse injury related to internal impingement. Abduction coupled with external rotation is believed to impinge on the rotator cuff, specifically the supraspinatus, and lead to undersurface tears that can progress to full-thickness tears. This impingement is believed to be worsened with increased range of motion and instability in overhead athletes. A retrospective review of seven patients diagnosed with rotator cuff injuries was performed to better understand this shoulder injury pattern. The type of sport played, a history of trauma, diagnosis, treatment method, and outcome were noted. Six patients were male and one was a female. Baseball was the primary sport for four patients, basketball for one, gymnastics for one, and wrestling for one. The following injury patterns were observed: two patients tore their subscapularis tendon, two sustained avulsion fractures of their lesser tuberosity, one tore his rotator interval, one tore his supraspinatus, and one avulsed his greater tuberosity. Only four patients recalled a specific traumatic event. Three patients were treated with arthroscopic rotator cuff repair, three with miniopen repair, and one was treated with rehabilitation. Six of the seven patients returned to their preinjury level of sport after treatment. Rotator cuff tears are rare in the adolescent age group. The injury patterns suggest that acute trauma likely accounts for many rotator cuff tears and their equivalents in the young patient. Adolescents with rotator cuff tears reliably return to sports after treatment. The possibility of rotator cuff tears in skeletally immature athletes should be considered. The prognosis is very good once this injury is identified and treated.

  2. Modeling rapidly rotating stars

    NASA Astrophysics Data System (ADS)

    Rieutord, M.

    2006-06-01

    We review the quest of modeling rapidly rotating stars during the past 40 years and detail the challenges to be taken up by models facing new data from interferometry, seismology, spectroscopy... We then present the progress of the ESTER project aimed at giving a physically self-consistent model for the structure and evolution of rapidly rotating stars.

  3. Rotatable shear plate interferometer

    DOEpatents

    Duffus, Richard C.

    1988-01-01

    A rotatable shear plate interferometer comprises a transparent shear plate mounted obliquely in a tubular supporting member at 45.degree. with respect to its horizontal center axis. This tubular supporting member is supported rotatably around its center axis and a collimated laser beam is made incident on the shear plate along this center axis such that defocus in different directions can be easily measured.

  4. The Weighted Oblimin Rotation.

    ERIC Educational Resources Information Center

    Lorenzo-Seva, Urbano

    2000-01-01

    Demonstrates that the weighting procedure proposed by E. Cureton and S. Mulaik (1975) can be applied to the Direct Oblimin approach of D. Clarkson and R. Jennrich (1988) to provide good results. The rotation method obtained is called Weighted Oblimin. Compared this method to other rotation methods with favorable results. (SLD)

  5. CONTROL ROD ROTATING MECHANISM

    DOEpatents

    Baumgarten, A.; Karalis, A.J.

    1961-11-28

    A threaded rotatable shaft is provided which rotates in response to linear movement of a nut, the shaft being surrounded by a pair of bellows members connected to either side of the nut to effectively seal the reactor from leakage and also to store up energy to shut down the reactor in the event of a power failure. (AEC)

  6. Serious rotator cuff injuries.

    PubMed

    Jobe, F W

    1983-07-01

    Usually, serious rotator cuff injuries can be operated upon and a high level of performance can be achieved afer surgery. This is not so for the substantial tears seen in baseball pitchers. However, a damaged rotator cuff can be rehabilitated and can recover from the threatened tear without surgery if detected early enough and given the proper treatment.

  7. Rotation sensor switch

    DOEpatents

    Sevec, John B.

    1978-01-01

    A protective device to provide a warning if a piece of rotating machinery slows or stops comprises a pair of hinged weights disposed to rotate on a rotating shaft of the equipment. When the equipment is rotating, the weights remain in a plane essentially perpendicular to the shaft and constitute part of an electrical circuit that is open. When the shaft slows or stops, the weights are attracted to a pair of concentric electrically conducting disks disposed in a plane perpendicular to the shaft and parallel to the plane of the weights when rotating. A disk magnet attracts the weights to the electrically conducting plates and maintains the electrical contact at the plates to complete an electrical circuit that can then provide an alarm signal.

  8. Stress field rotation or block rotation: An example from the Lake Mead fault system

    NASA Technical Reports Server (NTRS)

    Ron, Hagai; Nur, Amos; Aydin, Atilla

    1990-01-01

    The Coulomb criterion, as applied by Anderson (1951), has been widely used as the basis for inferring paleostresses from in situ fault slip data, assuming that faults are optimally oriented relative to the tectonic stress direction. Consequently if stress direction is fixed during deformation so must be the faults. Freund (1974) has shown that faults, when arranged in sets, must generally rotate as they slip. Nur et al., (1986) showed how sufficiently large rotations require the development of new sets of faults which are more favorably oriented to the principal direction of stress. This leads to the appearance of multiple fault sets in which older faults are offset by younger ones, both having the same sense of slip. Consequently correct paleostress analysis must include the possible effect of fault and material rotation, in addition to stress field rotation. The combined effects of stress field rotation and material rotation were investigated in the Lake Meade Fault System (LMFS) especially in the Hoover Dam area. Fault inversion results imply an apparent 60 degrees clockwise (CW) rotation of the stress field since mid-Miocene time. In contrast structural data from the rest of the Great Basin suggest only a 30 degrees CW stress field rotation. By incorporating paleomagnetic and seismic evidence, the 30 degrees discrepancy can be neatly resolved. Based on paleomagnetic declination anomalies, it is inferred that slip on NW trending right lateral faults caused a local 30 degrees counter-clockwise (CCW) rotation of blocks and faults in the Lake Mead area. Consequently the inferred 60 degrees CW rotation of the stress field in the LMFS consists of an actual 30 degrees CW rotation of the stress field (as for the entire Great Basin) plus a local 30 degrees CCW material rotation of the LMFS fault blocks.

  9. [Case of severely disabled child with refractive respiratory infection due to gastroesophageal reflux successfully controlled by using a button-shaped double lumen transgastric jejunal feeding tube].

    PubMed

    Nakagawa, Kanako; Tomikashi, Koichi; Takashima, Hidetaka; Kanemitsu, Daisuke; Sugimoto, Kengo; Iwase, Akiko; Abe, Yoshiaki; Nozuchi, Shinji

    2009-01-01

    A 12-year-old severely disabled woman child had been suffering from the refractive respiratory infection due to gastroesophageal reflux (GER) in years. However two transnasal catheters inserted to control GER, one was for feeding to the jejunum and the other was for decompression of the stomach, they were not effective against respiratory infection. Then, to resolve the problems, a button-shaped double lumen transgastric jejunal catheter was inserted into her jejunum via PEG in two-stage. After the procedure, the refractive respiratory infection due to GER could be successfully controlled. Additionally, by using the button-shaped catheter, any position came to be acceptable in daily life, for example in rehabilitation, sleeping and so on. Her ADL (activity of daily life) was well preserved.

  10. Effect of different levels of black cumin (Nigella sativa L.) on performance, intestinal Escherichia coli colonization and jejunal morphology in laying hens.

    PubMed

    Boka, J; Mahdavi, A H; Samie, A H; Jahanian, R

    2014-04-01

    This study was conducted to investigate the effects of different levels of black cumin seeds (Nigella sativa L.) on performance, intestinal Escherichia coli count and morphology of jejunal epithelial cells in laying hens. A total of 100 Leghorn laying hens (Hy-Line W-36) of 49 weeks old were randomly distributed among five cage replicates of five birds each. Experimental diets consisted of different levels (0%, 1%, 2% and 3% of diet) of dietary black cumin inclusion. The experimental period lasted for a total of 10 weeks, and egg quality indexes and laying hens' performance were measured as two 35-day trial periods. At the final day, two hens per replicate were slaughtered to investigate the influence of dietary treatments on intestinal E. coli colonization and morphology of jejunal cells. Although dietary black cumin in all supplementation levels decreased (p < 0.05) the enumeration of ileal E. coli, the morphological and histological alterations in small intestine such as enhancement of villus height to crypt depth ratio, increased goblet cell numbers and proliferation of lamina propria lymphatic follicles were observed after dietary supplementation with at least 2% black cumin. Dietary treatments decreased (p < 0.05) the concentration of serum cholesterol and triglycerides and increased (p < 0.05) serum HDL concentration and relative weight of pancreas; however, the egg yolk cholesterol was not influenced by dietary treatments. In addition, dietary supplementation with black cumin improved (p < 0.05) eggshell quality and Haugh unit. The best feed conversion ratio was obtained when diets were supplemented with 2% black cumin. This improvement was due to the increase (p < 0.05) in egg mass and contemporaneous decrease (p < 0.01) in feed consumption. The present results indicated that regardless of supplementation level, dietary inclusion of black cumin decreased E. coli enumeration in ileal digesta and improved serum lipid profile and eggshell quality, whereas the

  11. Jejunal microvilli atrophy and reduced nutrient transport in rats with advanced liver cirrhosis: improvement by Insulin-like Growth Factor I

    PubMed Central

    Castilla-Cortázar, Inma; Pascual, María; Urdaneta, Elena; Pardo, Javier; Puche, Juan Enrique; Vivas, Bárbara; Díaz-Casares, Amelia; García, María; Díaz-Sánchez, Matías; Varela-Nieto, Isabel; Castilla, Alberto; González-Barón, Salvador

    2004-01-01

    Background Previous results have shown that in rats with non-ascitic cirrhosis there is an altered transport of sugars and amino acids associated with elongated microvilli. These alterations returned to normal with the administration of Insulin-Like Growth Factor-I (IGF-I). The aims of this study were to explore the evolution of these alterations and analyse the effect of IGF-I in rats with advanced cirrhosis and ascites. Thus, jejunal structure and nutrient transport (D-galactose, L-leucine, L-proline, L-glutamic acid and L-cystine) were studied in rats with ascitic cirrhosis. Methods Advanced cirrhosis was induced by CCl4 inhalation and Phenobarbital administration for 30 weeks. Cirrhotic animals were divided into two groups which received IGF-I or saline during two weeks. Control group was studied in parallel. Jejunal microvilli were studied by electron microscopy. Nutrient transport was assessed in brush border membrane vesicles using 14C or 35S-labelled subtracts in the three experimental groups. Results Intestinal active Na+-dependent transport was significantly reduced in untreated cirrhotic rats. Kinetic studies showed a decreased Vmax and a reduced affinity for sugar and four amino acids transporters (expressed as an increased Kt) in the brush border membrane vesicles from untreated cirrhotic rats as compared with controls. Both parameters were normalised in the IGF-I-treated cirrhotic group. Electron microscopy showed elongation and fusion of microvilli with degenerative membrane lesions and/or notable atrophy. Conclusions The initial microvilli elongation reported in non ascitic cirrhosis develops into atrophy in rats with advanced cirrhosis and nutrient transports (monosaccharides and amino acids) are progressively reduced. Both morphological and functional alterations improved significantly with low doses of IGF-I. PMID:15196310

  12. The A0 blood group genotype modifies the jejunal glycomic binding pattern profile of piglets early associated with a simple or complex microbiota.

    PubMed

    Priori, D; Colombo, M; Koopmans, S-J; Jansman, A J M; van der Meulen, J; Trevisi, P; Bosi, P

    2016-02-01

    The intestinal epithelium glycocalyx sugar motif is an important determinant of the bacterial-host interaction and may be affected in pigs by gut microbiota and by blood group genotype. The aim was to study the effect of intestinal association with different microbiota and A0 blood group genotypes on the expressed glycomic pattern in the small intestine. Twelve caesarean-derived pigs previously associated with a simple association (SA) or complex association (CA) microbiota were selected at 26 to 37 d of age. In each subject, different jejunal loops were perfused for 8 h with enterotoxigenic K88 (ETEC), ETEC fimbriae (F4), (LAM), or a saline control. The piglets were genotyped for A0 blood group and the glycomic profile was evaluated by microscopic screening of lectin binding: peanut agglutinin (PNA), which is galactose specific; agglutinin I (UEA), which is fucose specific; lectin II (MALii), which is sialic acid specific; concavalin A, which is mannose specific; soybean agglutinin (SBA), which is -acetyl-galactosamine specific; and wheat germ agglutinin (WGA), which is -acetyl-glucosamine specific. A0 pigs had fewer UEA-positive cells, MALii-positive cells ( < 0.001), and SBA-positive cells ( < 0.10) than 00 pigs. Simple association pigs had more SBA positive cells ( < 0.01) than CA pigs. Enterotoxigenic K88-perfused intestinal loops had fewer UEA-positive cells ( < 0.01) and WGA positive cells ( < 0.001) cells and more PNA positive cells (only in SA pigs, < 0.01). No effects of introduction of F4 and LAM in the intestinal lumen were observed. The porcine A0 blood group genotype and the luminal presence of ETEC strongly affected the jejunal mucosa glycomic pattern profile whereas an early oral simple or complex microbial association had limited effects. Pig genetic background has relevance on the cross talk between intestinal epithelium glycocalyx sugar motif and ETEC and, ultimately, on the gut microbial colonization in later life. PMID:27065129

  13. How dynein and microtubules rotate the nucleus.

    PubMed

    Wu, Jun; Lee, Kristen C; Dickinson, Richard B; Lele, Tanmay P

    2011-10-01

    In living cells, a fluctuating torque is exerted on the nuclear surface but the origin of the torque is unclear. In this study, we found that the nuclear rotation angle is directionally persistent on a time scale of tens of minutes, but rotationally diffusive on longer time scales. Rotation required the activity of the microtubule motor dynein. We formulated a model based on microtubules undergoing dynamic instability, with tensional forces between a stationary centrosome and the nuclear surface mediated by dynein. Model simulations suggest that the persistence in rotation angle is due to the transient asymmetric configuration of microtubules exerting a net torque in one direction until the configuration is again randomized by dynamic instability. The model predicts that the rotational magnitude must depend on the distance between the nucleus and the centrosome. To test this prediction, rotation was quantified in patterned cells in which the cell's centrosome was close to the projected nuclear centroid. Consistent with the prediction, the angular displacement was found to decrease in these cells relative to unpatterned cells. This work provides the first mechanistic explanation for how nuclear dynein interactions with discrete microtubules emanating from a stationary centrosome cause rotational torque on the nucleus.

  14. ROTATIONAL DOPPLER BEAMING IN ECLIPSING BINARIES

    SciTech Connect

    Groot, Paul J.

    2012-01-20

    In eclipsing binaries the stellar rotation of the two components will cause a rotational Doppler beaming during eclipse ingress and egress when only part of the eclipsed component is covered. For eclipsing binaries with fast spinning components this photometric analog of the well-known spectroscopic Rossiter-McLaughlin effect can exceed the strength of the orbital effect. Example light curves are shown for a detached double white dwarf binary, a massive O-star binary and a transiting exoplanet case, similar to WASP-33b. Inclusion of the rotational Doppler beaming in eclipsing systems is a prerequisite for deriving the correct stellar parameters from fitting high-quality photometric light curves and can be used to determine stellar obliquities as well as, e.g., an independent measure of the rotational velocity in those systems that may be expected to be fully synchronized.

  15. ROTATING GLOBULAR CLUSTERS

    SciTech Connect

    Bianchini, P.; Varri, A. L.; Bertin, G.; Zocchi, A.

    2013-07-20

    Internal rotation is thought to play a major role in the dynamics of some globular clusters. However, in only a few cases has internal rotation been studied by the quantitative application of realistic and physically justified global models. Here, we present a dynamical analysis of the photometry and three-dimensional kinematics of {omega} Cen, 47 Tuc, and M15, by means of a recently introduced family of self-consistent axisymmetric rotating models. The three clusters, characterized by different relaxation conditions, show evidence of differential rotation and deviations from sphericity. The combination of line-of-sight velocities and proper motions allows us to determine their internal dynamics, predict their morphology, and estimate their dynamical distance. The well-relaxed cluster 47 Tuc is interpreted very well by our model; internal rotation is found to explain the observed morphology. For M15, we provide a global model in good agreement with the data, including the central behavior of the rotation profile and the shape of the ellipticity profile. For the partially relaxed cluster {omega} Cen, the selected model reproduces the complex three-dimensional kinematics; in particular, the observed anisotropy profile, characterized by a transition from isotropy to weakly radial anisotropy and then to tangential anisotropy in the outer parts. The discrepancy found for the steep central gradient in the observed line-of-sight velocity dispersion profile and for the ellipticity profile is ascribed to the condition of only partial relaxation of this cluster and the interplay between rotation and radial anisotropy.

  16. Rotating reactor studies

    NASA Technical Reports Server (NTRS)

    Roberts, Glyn O.

    1991-01-01

    Undesired gravitational effects such as convection or sedimentation in a fluid can sometimes be avoided or decreased by the use of a closed chamber uniformly rotated about a horizontal axis. In a previous study, the spiral orbits of a heavy or buoyant particle in a uniformly rotating fluid were determined. The particles move in circles, and spiral in or out under the combined effects of the centrifugal force and centrifugal buoyancy. A optimization problem for the rotation rate of a cylindrical reactor rotated about its axis and containing distributed particles was formulated and solved. Related studies in several areas are addressed. A computer program based on the analysis was upgraded by correcting some minor errors, adding a sophisticated screen-and-printer graphics capability and other output options, and by improving the automation. The design, performance, and analysis of a series of experiments with monodisperse polystyrene latex microspheres in water were supported to test the theory and its limitations. The theory was amply confirmed at high rotation rates. However, at low rotation rates (1 rpm or less) the assumption of uniform solid-body rotation of the fluid became invalid, and there were increasingly strong secondary motions driven by variations in the mean fluid density due to variations in the particle concentration. In these tests the increase in the mean fluid density due to the particles was of order 0.015 percent. To a first approximation, these flows are driven by the buoyancy in a thin crescent-shaped depleted layer on the descending side of the rotating reactor. This buoyancy distribution is balanced by viscosity near the walls, and by the Coriolis force in the interior. A full analysis is beyond the scope of this study. Secondary flows are likely to be stronger for buoyant particles, which spiral in towards the neutral point near the rotation axis under the influence of their centrifugal buoyancy. This is because the depleted layer is

  17. Rotatable seal assembly. [Patent application; rotating targets

    DOEpatents

    Logan, C.M.; Garibaldi, J.L.

    1980-11-12

    An assembly is provided for rotatably supporting a rotor on a stator so that vacuum chambers in the rotor and stator remain in communication while the chambers are sealed from ambient air, which enables the use of a ball bearing or the like to support most of the weight of the rotor. The apparatus includes a seal device mounted on the rotor to rotate therewith, but shiftable in position on the rotor while being sealed to the rotor as by an O-ring. The seal device has a flat face that is biased towards a flat face on the stator, and pressurized air is pumped between the faces to prevent contact between them while spacing them a small distance apart to avoid the inflow of large amounts of air between the faces and into the vacuum chambers.

  18. Three-dimensional simulation of a rotating supernova

    NASA Astrophysics Data System (ADS)

    Nakamura, K.; Kuroda, T.; Takiwaki, T.; Kotake, K.

    2014-05-01

    We investigate the effects of rotation on the evolution of core-collapse supernova explosion using a 15 solar mass progenitor model with a variety of neutrino luminosity and rotational velocity. Stars should have some amount of angular momentum, which would affect stellar evolution and its final explosion. In this paper we focus on the effect of rotation on gravitational collapse of a core, on a core bounce of accreting matter, and on subsequent generation and evolution of a shock wave. We find that the rotation plays a positive role for supernova explosions. More rapidly rotating models present more rapid expansion of the shock front and more energetic explosions. When the rotational speed is moderate, the shock once stalls at about 200 km away from the center similarly to a non-rotating model. Then the rotating progenitor experiences effective neutrino heating especially around an equatorial plane and explodes even with somewhat low neutrino luminosity for which the non-rotating model cannot overcome accreting matter and finally collapses. When the rotational speed is fast, the shock expands to about 300 km immediately after the core bounce and then evolves to move outward without shock stalling. We conclude that this positive effect of rotation to explosions is dominant against some possible negative aspects, for example, lower neutrino luminosity caused by less contraction of the rotating core.

  19. Three-dimensional simulation of a rotating supernova

    SciTech Connect

    Nakamura, K.; Kuroda, T.; Takiwaki, T.; Kotake, K.

    2014-05-02

    We investigate the effects of rotation on the evolution of core-collapse supernova explosion using a 15 solar mass progenitor model with a variety of neutrino luminosity and rotational velocity. Stars should have some amount of angular momentum, which would affect stellar evolution and its final explosion. In this paper we focus on the effect of rotation on gravitational collapse of a core, on a core bounce of accreting matter, and on subsequent generation and evolution of a shock wave. We find that the rotation plays a positive role for supernova explosions. More rapidly rotating models present more rapid expansion of the shock front and more energetic explosions. When the rotational speed is moderate, the shock once stalls at about 200 km away from the center similarly to a non-rotating model. Then the rotating progenitor experiences effective neutrino heating especially around an equatorial plane and explodes even with somewhat low neutrino luminosity for which the non-rotating model cannot overcome accreting matter and finally collapses. When the rotational speed is fast, the shock expands to about 300 km immediately after the core bounce and then evolves to move outward without shock stalling. We conclude that this positive effect of rotation to explosions is dominant against some possible negative aspects, for example, lower neutrino luminosity caused by less contraction of the rotating core.

  20. Acoustic rotation control

    NASA Technical Reports Server (NTRS)

    Elleman, D. D.; Croonquist, A. P.; Wang, T. G. (Inventor)

    1983-01-01

    A system is described for acoustically controlled rotation of a levitated object, which avoids deformation of a levitated liquid object. Acoustic waves of the same wavelength are directed along perpendicular directions across the object, and with the relative phases of the acoustic waves repeatedly switched so that one wave alternately leads and lags the other by 90 deg. The amount of torque for rotating the object, and the direction of rotation, are controlled by controlling the proportion of time one wave leads the other and selecting which wave leads the other most of the time.

  1. Chaotic rotation of Hyperion?

    NASA Technical Reports Server (NTRS)

    Binzel, R. P.; Green, J. R.; Opal, C. B.

    1986-01-01

    Thomas et al. (1984) analyzed 14 Voyager 2 images of Saturn's satellite Hyperion and interpreted them to be consistent with a coherent (nonchaotic) rotation period of 13.1 days. This interpretation was criticized by Peale and Wisdom (1984), who argued that the low sampling frequency of Voyager data does not allow chaotic or nonchaotic rotation to be distinguished. New observations obtained with a higher sampling frequency are reported here which conclusively show that the 13.1 day period found by Thomas et al. was not due to coherent rotation.

  2. Exciting Molecules Close to the Rotational Quantum Resonance: Anderson Wall and Rotational Bloch Oscillations.

    PubMed

    Floß, Johannes; Averbukh, Ilya Sh

    2016-05-19

    We describe a universal behavior of linear molecules excited by a periodic train of short laser pulses under conditions close to the quantum resonance. The quantum resonance effect causes an unlimited ballistic growth of the angular momentum. We show that a disturbance of the quantum resonance, either by the centrifugal distortion of the rotating molecules or a controlled detuning of the pulse train period from the so-called rotational revival time, eventually halts the growth by causing Anderson localization beyond a critical value of the angular momentum, the Anderson wall. Below the wall, the rotational excitation oscillates with the number of pulses due to a mechanism similar to Bloch oscillations in crystalline solids. We suggest optical experiments capable of observing the rotational Anderson wall and Bloch oscillations at near-ambient conditions with the help of existing laser technology.

  3. What does physical rotation reveal about mental rotation?

    PubMed

    Gardony, Aaron L; Taylor, Holly A; Brunyé, Tad T

    2014-02-01

    In a classic psychological science experiment, Shepard and Metzler (1971) discovered that the time participants took to judge whether two rotated abstract block figures were identical increased monotonically with the figures' relative angular disparity. They posited that participants rotate mental images to achieve a match and that mental rotation recruits motor processes. This interpretation has become central in the literature, but until now, surprisingly few researchers have compared mental and physical rotation. We had participants rotate virtual Shepard and Metzler figures mentally and physically; response time, accuracy, and real-time rotation data were collected. Results suggest that mental and physical rotation processes overlap and also reveal novel conclusions about physical rotation that have implications for mental rotation. Notably, participants did not rotate figures to achieve a match, but rather until they reached an off-axis canonical difference, and rotational strategies markedly differed for judgments of whether the figures were the same or different.

  4. The Rotating Mirror.

    ERIC Educational Resources Information Center

    Greenslade, Thomas B., Jr.

    1981-01-01

    Discusses theory of the rotating mirror, its use in measuring the velocity of the electrical signal in wires, and the velocity of light. Concludes with a description of the manometric flame apparatus developed for analyzing sound waves. (SK)

  5. Rotating mobile launcher

    NASA Technical Reports Server (NTRS)

    Gregory, T. J.

    1977-01-01

    Apparatus holds remotely piloted arm that accelerates until launching speed is reached. Then vehicle and counterweight at other end of arm are released simultaneously to avoid structural damage from unbalanced rotating forces.

  6. Pumping of water through carbon nanotubes by rotating electric field and rotating magnetic field

    NASA Astrophysics Data System (ADS)

    Li, Xiao-Peng; Kong, Gao-Pan; Zhang, Xing; He, Guo-Wei

    2013-09-01

    Using molecular dynamics simulations, we demonstrate pumping of water through a carbon nanotube by applying the combination of a rotating electric field and a rotating magnetic field. The driving force is a Lorentz force generated from the motion of charges in the magnetic field, and the motion is caused by the rotation of the electric field. We find that there exits a linear relationship between the average pumping velocity v and magnetic field strength B, which can be used to control the flux of the continuous unidirectional water flow. This approach is expected to be used in liquid circulation without a pressure gradient.

  7. Rotating arc spark plug

    DOEpatents

    Whealton, John H.; Tsai, Chin-Chi

    2003-05-27

    A spark plug device includes a structure for modification of an arc, the modification including arc rotation. The spark plug can be used in a combustion engine to reduce emissions and/or improve fuel economy. A method for operating a spark plug and a combustion engine having the spark plug device includes the step of modifying an arc, the modifying including rotating the arc.

  8. Robot Grasps Rotating Object

    NASA Technical Reports Server (NTRS)

    Wilcox, Brian H.; Tso, Kam S.; Litwin, Todd E.; Hayati, Samad A.; Bon, Bruce B.

    1991-01-01

    Experimental robotic system semiautomatically grasps rotating object, stops rotation, and pulls object to rest in fixture. Based on combination of advanced techniques for sensing and control, constructed to test concepts for robotic recapture of spinning artificial satellites. Potential terrestrial applications for technology developed with help of system includes tracking and grasping of industrial parts on conveyor belts, tracking of vehicles and animals, and soft grasping of moving objects in general.

  9. Rotating superfluid turbulence.

    PubMed

    Tsubota, Makoto; Araki, Tsunehiko; Barenghi, Carlo F

    2003-05-23

    Almost all studies of vortex states in helium II have been concerned with either ordered vortex arrays or disordered vortex tangles. This work numerically studies what happens in the presence of both rotation (which induces order) and thermal counterflow (which induces disorder). We find a new statistically steady state in which the vortex tangle is polarized along the rotational axis. Our results are used to interpret an instability that was discovered experimentally by Swanson et al. [Phys. Rev. Lett. 50, 190 (1983)

  10. Electromagnetic rotational actuation.

    SciTech Connect

    Hogan, Alexander Lee

    2010-08-01

    There are many applications that need a meso-scale rotational actuator. These applications have been left by the wayside because of the lack of actuation at this scale. Sandia National Laboratories has many unique fabrication technologies that could be used to create an electromagnetic actuator at this scale. There are also many designs to be explored. In this internship exploration of the designs and fabrications technologies to find an inexpensive design that can be used for prototyping the electromagnetic rotational actuator.

  11. Instability in Rotating Machinery

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The proceedings contain 45 papers on a wide range of subjects including flow generated instabilities in fluid flow machines, cracked shaft detection, case histories of instability phenomena in compressors, turbines, and pumps, vibration control in turbomachinery (including antiswirl techniques), and the simulation and estimation of destabilizing forces in rotating machines. The symposium was held to serve as an update on the understanding and control of rotating machinery instability problems.

  12. Rotational rate sensor

    DOEpatents

    Hunter, Steven L.

    2002-01-01

    A rate sensor for angular/rotational acceleration includes a housing defining a fluid cavity essentially completely filled with an electrolyte fluid. Within the housing, such as a toroid, ions in the fluid are swept during movement from an excitation electrode toward one of two output electrodes to provide a signal for directional rotation. One or more ground electrodes within the housing serve to neutralize ions, thus preventing any effect at the other output electrode.

  13. Automated shell theory for rotating structures (ASTROS)

    NASA Technical Reports Server (NTRS)

    Foster, B. J.; Thomas, J. M.

    1971-01-01

    A computer program for analyzing axisymmetric shells with inertial forces caused by rotation about the shell axis is developed by revising the STARS II shell program. The basic capabilities of the STARS II shell program, such as the treatment of the branched shells, stiffened wall construction, and thermal gradients, are retained.

  14. Rotating superconductor magnet for producing rotating lobed magnetic field lines

    DOEpatents

    Hilal, Sadek K.; Sampson, William B.; Leonard, Edward F.

    1978-01-01

    This invention provides a rotating superconductor magnet for producing a rotating lobed magnetic field, comprising a cryostat; a superconducting magnet in the cryostat having a collar for producing a lobed magnetic field having oppositely directed adjacent field lines; rotatable support means for selectively rotating the superconductor magnet; and means for energizing the superconductor magnet.

  15. Unsteady granular flows in a rotating tumbler.

    PubMed

    Pohlman, Nicholas A; Ottino, Julio M; Lueptow, Richard M

    2009-09-01

    The characteristics of steady granular flow in quasi-two-dimensional rotating tumblers have been thoroughly investigated and are fairly well understood. However, unsteady time-varying flow has not been studied in detail. The linear response of granular flow in quasi-two-dimensional rotating tumblers is presented for periodic forcing protocols via sinusoidal variation in the rotational speed of the tumbler and for step changes in rotational speed. Variations in the tumbler radius, particle size, and forcing frequency are explored. Similarities to steady flow include the fastest flow occurring at the free surface of the flowing layer and an instantaneous approximately linear velocity profile through the depth. The flowing layer depth varies by 2-5 particle diameters between minimum and maximum rotation rates. However, unsteady forcing also causes the flow to exhibit dynamic properties. For periodic rotational speeds, the phase lag of the flowing layer depth increases linearly with increasing input forcing frequency up to nearly 2.0 rad over 0-20 cycles per tumbler revolution. The amplitude responses of the velocity and shear rate show a resonance behavior unique to the system level parameters. The phase lag of all flow properties appears to be related to the number of particle contacts from the edge of the rotating tumbler. Characterization via step changes in rotational speed shows dynamic properties of overshoot (up to 35%) and rise times on the order of 0.2-0.7 s. The results suggest that the unsteady granular flow analysis may be beneficial for characterizing the "flowability" and "rheology" of granular materials based on particle size, moisture content, or other properties. PMID:19905105

  16. Re-feeding rats a high-sucrose diet after 3 days of starvation enhances histone H3 acetylation in transcribed region and expression of jejunal GLUT5 gene.

    PubMed

    Honma, Kazue; Masuda, Yuriko; Mochizuki, Kazuki; Goda, Toshinao

    2014-01-01

    Fasting for 3 days leads to reduction in the expression of GLUT5 and SGLT1 genes in jejunum. Re-feeding a high-sucrose diet in fasted rats enhanced mRNA levels and histone H3 acetylation on transcribed region of GLUT5 gene within 24 h, but not in SGLT1. Responsiveness of jejunal GLUT5 gene is associated with changes in histone H3 acetylation on transcribed region.

  17. Rotation Rates of the Giant Planets (Invited)

    NASA Astrophysics Data System (ADS)

    Schubert, G.; Helled, R.; Anderson, J. D.

    2009-12-01

    atmospheric motions (Anderson, J.D. and G. Schubert, 2007, Saturn’s gravitational field, internal rotation, and interior structure, Science, 317, 1384-1387 [doi: 10.1126/science.1144835]; Read, P.L., T.E. Dowling, and G. Schubert, Saturn’s rotation period from its atmospheric planetary-wave configuration, 2009, Nature, 460, 608-610 [doi:10.1038/nature08194 Letter]) have inferred planetary rotation periods significantly shorter than the Voyager period, implying Jovian-like atmospheric winds. The inferred shapes (oblateness) of Uranus and Neptune are inconsistent with heretofore accepted planetary rotation rates. Either the shapes or the rotation periods of the icy giants are not well determined. If the magnetic fields of Uranus and Neptune are generated in relatively thin shells (Stanley, S., and J. Bloxham, Convective-region geometry as the cause of Uranus’ and Neptune’s unusual magnetic fields, Nature, 428, 151-153 [doi:10.1038/nature02376] Letter), then the periodicities of the fields might not reflect the rotation of the bulk of the planets.

  18. Rotating Aperture System

    DOEpatents

    Rusnak, Brian; Hall, James M.; Shen, Stewart; Wood, Richard L.

    2005-01-18

    A rotating aperture system includes a low-pressure vacuum pumping stage with apertures for passage of a deuterium beam. A stator assembly includes holes for passage of the beam. The rotor assembly includes a shaft connected to a deuterium gas cell or a crossflow venturi that has a single aperture on each side that together align with holes every rotation. The rotating apertures are synchronized with the firing of the deuterium beam such that the beam fires through a clear aperture and passes into the Xe gas beam stop. Portions of the rotor are lapped into the stator to improve the sealing surfaces, to prevent rapid escape of the deuterium gas from the gas cell.

  19. IO Rotation Movie

    NASA Technical Reports Server (NTRS)

    2000-01-01

    During its 1979 flyby, Voyager 2 observed Io only from a distance. However, the volcanic activity discovered by Voyager 1 months earlier was readily visible. This sequence of nine color images was collected using the Blue, Green and Orange filters from about 1.2 million kilometers. A 2.5 hour period is covered during which Io rotates 7 degrees.

    Rotating into view over the limb of Io are the plumes of the volcanoes Amirani (top) and Maui (lower). These plumes are very distinct against the black sky because they are being illuminated from behind. Notice that as Io rotates, the proportion of Io which is sunlit decreases greatly. This changing phase angle is because Io is moving between the spacecraft and the Sun.

    This time-lapse movie was produced at JPL by the Image Processing Laboratory in 1985.

  20. Chiral rotational spectroscopy

    NASA Astrophysics Data System (ADS)

    Cameron, Robert P.; Götte, Jörg B.; Barnett, Stephen M.

    2016-09-01

    We introduce chiral rotational spectroscopy, a technique that enables the determination of the orientated optical activity pseudotensor components BX X, BY Y, and BZ Z of chiral molecules, in a manner that reveals the enantiomeric constitution of a sample and provides an incisive signal even for a racemate. Chiral rotational spectroscopy could find particular use in the analysis of molecules that are chiral solely by virtue of their isotopic constitution and molecules with multiple chiral centers. A basic design for a chiral rotational spectrometer together with a model of its functionality is given. Our proposed technique offers the more familiar polarizability components αX X, αY Y, and αZ Z as by-products, which could see it find use even for achiral molecules.

  1. Prediction and removal of rotation noise in airborne EM systems

    NASA Astrophysics Data System (ADS)

    Kratzer, Terence 12Macnae, James

    2014-03-01

    We aim to eliminate or reduce significant impediments to conductive target detection and conductive cover penetration in airborne electromagnetic (AEM) systems. Existing limitations come from the very high noise encountered at low base frequencies, caused by rotations of vector magnetic field sensors in the Earth's magnetic field. We use the output of tri-axial rotation-rate sensors to predict and subtract the rotation noise from rigidly coupled ARMIT magnetic field sensors. The approach is successful in reducing rotation noise by one to two orders of magnitude at low frequencies.

  2. Rotation of Giant Stars

    NASA Astrophysics Data System (ADS)

    Kissin, Yevgeni; Thompson, Christopher

    2015-07-01

    The internal rotation of post-main sequence stars is investigated, in response to the convective pumping of angular momentum toward the stellar core, combined with a tight magnetic coupling between core and envelope. The spin evolution is calculated using model stars of initial mass 1, 1.5, and 5 {M}ȯ , taking into account mass loss on the giant branches. We also include the deposition of orbital angular momentum from a sub-stellar companion, as influenced by tidal drag along with the excitation of orbital eccentricity by a fluctuating gravitational quadrupole moment. A range of angular velocity profiles {{Ω }}(r) is considered in the envelope, extending from solid rotation to constant specific angular momentum. We focus on the backreaction of the Coriolis force, and the threshold for dynamo action in the inner envelope. Quantitative agreement with measurements of core rotation in subgiants and post-He core flash stars by Kepler is obtained with a two-layer angular velocity profile: uniform specific angular momentum where the Coriolis parameter {Co}\\equiv {{Ω }}{τ }{con}≲ 1 (here {τ }{con} is the convective time), and {{Ω }}(r)\\propto {r}-1 where {Co}≳ 1. The inner profile is interpreted in terms of a balance between the Coriolis force and angular pressure gradients driven by radially extended convective plumes. Inward angular momentum pumping reduces the surface rotation of subgiants, and the need for a rejuvenated magnetic wind torque. The co-evolution of internal magnetic fields and rotation is considered in Kissin & Thompson, along with the breaking of the rotational coupling between core and envelope due to heavy mass loss.

  3. Multiple giant diverticula of the jejunum causing intestinal obstruction: report of a case and review of the literature

    PubMed Central

    2011-01-01

    Multiple diverticulosis of jejunum represents an uncommon pathology of the small bowel. The disease is usually asymptomatic and must be taken into consideration in cases of unexplained malabsorption, anemia, chronic abdominal pain or discomfort. Related complications such as diverticulitis, perforation, bleeding or intestinal obstruction appear in 10-30% of the patients increasing morbidity and mortality rates. We herein report a case of a 55 year-old man presented at the emergency department with acute abdominal pain, vomiting and fever. Preoperative radiological examination followed by laparotomy revealed multiple giant jejunal diverticula causing intestinal obstruction. We also review the literature for this uncommon disease. PMID:21385440

  4. Rotating shielded crane system

    DOEpatents

    Commander, John C.

    1988-01-01

    A rotating, radiation shielded crane system for use in a high radiation test cell, comprises a radiation shielding wall, a cylindrical ceiling made of radiation shielding material and a rotatable crane disposed above the ceiling. The ceiling rests on an annular ledge intergrally attached to the inner surface of the shielding wall. Removable plugs in the ceiling provide access for the crane from the top of the ceiling into the test cell. A seal is provided at the interface between the inner surface of the shielding wall and the ceiling.

  5. Rotating quantum states

    NASA Astrophysics Data System (ADS)

    Ambruş, Victor E.; Winstanley, Elizabeth

    2014-06-01

    We revisit the definition of rotating thermal states for scalar and fermion fields in unbounded Minkowski space-time. For scalar fields such states are ill-defined everywhere, but for fermion fields an appropriate definition of the vacuum gives thermal states regular inside the speed-of-light surface. For a massless fermion field, we derive analytic expressions for the thermal expectation values of the fermion current and stress-energy tensor. These expressions may provide qualitative insights into the behaviour of thermal rotating states on more complex space-time geometries.

  6. Rotating flexible drag mill

    DOEpatents

    Pepper, W.B.

    1984-05-09

    A rotating parachute for decelerating objects travelling through atmosphere at subsonic or supersonic deployment speeds includes a circular canopy having a plurality of circumferentially arranged flexible panels projecting radially from a solid central disk. A slot extends radially between adjacent panels to the outer periphery of the canopy. Upon deployment, the solid disk diverts air radially to rapidly inflate the panels into a position of maximum diameter. Air impinging on the panels adjacent the panel slots rotates the parachute during its descent. Centrifugal force flattens the canopy into a constant maximum diameter during terminal descent for maximum drag and deceleration.

  7. Rotating bubble membrane radiator

    DOEpatents

    Webb, Brent J.; Coomes, Edmund P.

    1988-12-06

    A heat radiator useful for expelling waste heat from a power generating system aboard a space vehicle is disclosed. Liquid to be cooled is passed to the interior of a rotating bubble membrane radiator, where it is sprayed into the interior of the bubble. Liquid impacting upon the interior surface of the bubble is cooled and the heat radiated from the outer surface of the membrane. Cooled liquid is collected by the action of centrifical force about the equator of the rotating membrane and returned to the power system. Details regarding a complete space power system employing the radiator are given.

  8. Rotation and vibration-rotation spectrum of FeH

    SciTech Connect

    Phillips, J.G.; Davis, S.P.

    1988-02-01

    The far-IR rotation and fundamental vibration-rotation spectra of the FeH molecule's 4Delta-4Delta system are calculated. The vibration-rotation band is in the middle of a band in the water spectrum, so that it will have to be searched for from outer space. In the case of the rotation spectrum, the feature to look for is the rotation line at 1411 GHz, which is produced by the transition between the two lowest rotational levels of the lowest (7/2) subband. This feature can be looked for from the ground. 14 references.

  9. Anisotropy in rotating drums

    NASA Astrophysics Data System (ADS)

    Povall, Timothy; McBride, Andrew; Govender, Indresan

    2015-11-01

    An anisotropic relationship between the stress and the strain rate has been observed in two-dimensional simulations of rotating drums. The objective of this work is to investigate the structure of the constitutive relation using three-dimensional discrete-element-method simulations of a rotating drum containing identical rigid spheres for a range of rotational speeds. Anisotropy is quantified from the alignment of the stress and strain rate tensors, with the strain rate computed using a least-squares fit. It is shown that in certain regions there is a strong anisotropic relationship, regardless of the speed of rotation. The effective friction coefficient is examined in order to determine the phase space in which the μ (I) rheology is valid. Lastly, a depth-averaged approach through the flowing layer is employed to determine the relationship between the velocity tangential to the equilibrium surface and the height of the flowing layer. A power-law relationship that approaches linear at high speeds is observed. Supported by NRF/DST Scarce Skills (South Africa).

  10. Rotating Saddle Paul Trap.

    ERIC Educational Resources Information Center

    Rueckner, Wolfgang; And Others

    1995-01-01

    Describes a demonstration in which a ball is placed in an unstable position on a saddle shape. The ball becomes stable when it is rotated above some threshold angular velocity. The demonstration is a mechanical analog of confining a particle in a "Paul Trap". (DDR)

  11. Rotational speed control

    NASA Technical Reports Server (NTRS)

    Bastin, Paul

    1990-01-01

    Viewgraphs on rotational speed control are presented. The Centrifuge Facility Systems Study - 2.5 m centrifuge is shown. A life sciences centrifuge is scheduled to fly aboard Space Station Freedom. Live animal and plant specimens will be carried on the rotor and compared with microgravity specimens in racks.

  12. Rotational Dynamics with Tracker

    ERIC Educational Resources Information Center

    Eadkhong, T.; Rajsadorn, R.; Jannual, P.; Danworaphong, S.

    2012-01-01

    We propose the use of Tracker, freeware for video analysis, to analyse the moment of inertia ("I") of a cylindrical plate. Three experiments are performed to validate the proposed method. The first experiment is dedicated to find the linear coefficient of rotational friction ("b") for our system. By omitting the effect of such friction, we derive…

  13. Rotator cuff repair

    MedlinePlus

    ... torn rotator cuff is usually successful in relieving pain in the shoulder. The procedure may not always return strength to ... may not fully heal. Stiffness, weakness, and chronic pain may still be ... are not followed. Older patients (over age 65). Smoking.

  14. Rotator Cuff Injuries.

    ERIC Educational Resources Information Center

    Connors, G. Patrick

    Many baseball players suffer from shoulder injuries related to the rotator cuff muscles. These injuries may be classified as muscular strain, tendonitis or tenosynovitis, and impingement syndrome. Treatment varies from simple rest to surgery, so it is important to be seen by a physician as soon as possible. In order to prevent these injuries, the…

  15. Rotational waves in geodynamics

    NASA Astrophysics Data System (ADS)

    Gerus, Artyom; Vikulin, Alexander

    2015-04-01

    The rotation model of a geoblock with intrinsic momentum was constructed by A.V. Vikulin and A.G. Ivanchin [9, 10] to describe seismicity within the Pacific Ocean margin. It is based on the idea of a rotational motion of geoblocks as the parts of the rotating body of the Earth that generates rotary deformation waves. The law of the block motion was derived in the form of the sine-Gordon equation (SG) [5, 9]; the dimensionless form of the equation is: δ2θ δ2θ δξ2 - δη2 = sinθ, (1) where θ = β/2, ξ = k0z and η = v0k0t are dimensionless coordinates, z - length of the chain of masses (blocks), t - time, β - turn angle, ν0 - representative velocity of the process, k0 - wave number. Another case analyzed was a chain of nonuniformly rotating blocks, with deviation of force moments from equilibrium positions μ, considering friction forces α along boundaries, which better matched a real-life seismic process. As a result, the authors obtained the law of motion for a block in a chain in the form of the modified SG equation [8]: δ2θ δ2θ δθ- δξ2 - δ η2 = sin θ+ α δη + μδ(ξ)sin θ (2)

  16. Rotating Responsibility Reaps Rewards.

    ERIC Educational Resources Information Center

    Wilson, Barbara; Schullery, Nancy

    2000-01-01

    Describes a process used for group assignments in a business communication course which holds all group members accountable by using a structure of rotating responsibility. Discusses selecting assignments and implementing the process, noting how this structure requires equivalent advance preparation from all members and provides opportunities for…

  17. Concepts in crop rotations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Crop rotations have been a part of civilization since the Middle Ages. With colonization of what would become the United States came new crops of tobacco, cotton, and corn, the first two of which would play significant roles in both the economic beginnings and social fabric of the new country, how ...

  18. Troubleshooting rotating equipment

    SciTech Connect

    Wong, R.F. )

    1992-10-01

    This paper reports that equipment problems in a Peruvian refinery illustrate the process engineer's role as a troubleshooter. Examples show that rotating equipment problems can stem from mechanical or process factors and involve both inspection/maintenance specialists and process engineers.

  19. Rotatable stem and lock

    DOEpatents

    Deveney, J.E.; Sanderson, S.N.

    1981-10-27

    A valve stem and lock is disclosed which includes a housing surrounding a valve stem, a solenoid affixed to an interior wall of the housing, an armature affixed to the valve stem and a locking device for coupling the armature to the housing body. When the solenoid is energized, the solenoid moves away from the housing body, permitting rotation of the valve stem.

  20. Rotatable stem and lock

    DOEpatents

    Deveney, Joseph E.; Sanderson, Stephen N.

    1984-01-01

    A valve stem and lock include a housing surrounding a valve stem, a solenoid affixed to an interior wall of the housing, an armature affixed to the valve stem and a locking device for coupling the armature to the housing body. When the solenoid is energized, the solenoid moves away from the housing body, permitting rotation of the valve stem.

  1. The Rotational and Gravitational Effect of Earthquakes

    NASA Technical Reports Server (NTRS)

    Gross, Richard

    2000-01-01

    The static displacement field generated by an earthquake has the effect of rearranging the Earth's mass distribution and will consequently cause the Earth's rotation and gravitational field to change. Although the coseismic effect of earthquakes on the Earth's rotation and gravitational field have been modeled in the past, no unambiguous observations of this effect have yet been made. However, the Gravity Recovery And Climate Experiment (GRACE) satellite, which is scheduled to be launched in 2001, will measure time variations of the Earth's gravitational field to high degree and order with unprecedented accuracy. In this presentation, the modeled coseismic effect of earthquakes upon the Earth's gravitational field to degree and order 100 will be computed and compared to the expected accuracy of the GRACE measurements. In addition, the modeled second degree changes, corresponding to changes in the Earth's rotation, will be compared to length-of-day and polar motion excitation observations.

  2. Earth Rotation Dynamics: Review and Prospects

    NASA Technical Reports Server (NTRS)

    Chao, Benjamin F.

    2004-01-01

    Modem space geodetic measurement of Earth rotation variations, particularly by means of the VLBI technique, has over the years allowed studies of Earth rotation dynamics to advance in ever-increasing precision, accuracy, and temporal resolution. A review will be presented on our understanding of the geophysical and climatic causes, or "excitations", for length-of-day change, polar motion, and nutations. These excitations sources come from mass transports that constantly take place in the Earth system comprised of the atmosphere, hydrosphere, cryosphere, lithosphere, mantle, and the cores. In this sense, together with other space geodetic measurements of time-variable gravity and geocenter motion, Earth rotation variations become a remote-sensing tool for the integral of all mass transports, providing valuable information about the latter on a wide range of spatial and temporal scales. Future prospects with respect to geophysical studies with even higher accuracy and resolution will be discussed.

  3. Instability of a rotating liquid ring.

    PubMed

    Zhao, Sicheng; Tao, Jianjun

    2013-09-01

    It is shown numerically that a rotating inviscid liquid ring has a temporally oscillating state, where the radius of the ring varies periodically because of the competition between the centrifugal force and the centripetal force caused by the surface tension. Stability analysis reveals that an enlarging or shrinking ring is unstable to a varicose-type mode, which is affected by both the radial velocity and the radius ratio between the cross section and the ring. Furthermore, uniform rotation of a ring leads to a traveling unstable mode, whose frequency is determined by a simple sinuous mode, while the surface shape is modulated by the varicose mode and twisted by the rotation-induced Coriolis force. PMID:24125353

  4. Instability of a rotating liquid ring

    NASA Astrophysics Data System (ADS)

    Zhao, Sicheng; Tao, Jianjun

    2013-09-01

    It is shown numerically that a rotating inviscid liquid ring has a temporally oscillating state, where the radius of the ring varies periodically because of the competition between the centrifugal force and the centripetal force caused by the surface tension. Stability analysis reveals that an enlarging or shrinking ring is unstable to a varicose-type mode, which is affected by both the radial velocity and the radius ratio between the cross section and the ring. Furthermore, uniform rotation of a ring leads to a traveling unstable mode, whose frequency is determined by a simple sinuous mode, while the surface shape is modulated by the varicose mode and twisted by the rotation-induced Coriolis force.

  5. Management of a Septic Open Abdomen Patient with Spontaneous Jejunal Perforation after Emergent C/S with Confounding Factor of Mild Acute Pancreatitis

    PubMed Central

    Yetisir, Fahri; Sarer, Akgün Ebru; Acar, Hasan Zafer; Osmanoglu, Gokhan; Özer, Mehmet; Yaylak, Faik

    2016-01-01

    Introduction. We report the management of a septic Open Abdomen (OA) patient by the help of negative pressure therapy (NPT) and abdominal reapproximation anchor (ABRA) system in pregnant woman with spontaneous jejunal perforation after emergent cesarean section (C/S) with confounding factor of mild acute pancreatitis (AP). Presentation of Case. A 29-year-old and 34-week pregnant woman with AP underwent C/S. She was arrested after anesthesia induction and responded to cardiopulmonary resuscitation (CPR). There were only ash-colored serosanguinous fluid within abdomen during C/S. After C/S, she was transferred to intensive care unit (ICU) with vasopressor support. On postoperative 1st day, she underwent reoperation due to fecal fluid coming near the drainage. Leakage point could not be identified exactly and operation had to be deliberately abbreviated due to hemodynamic instability. NPT was applied. Two days later source control was provided by conversion of enteroatmospheric fistula (EAF) to jejunostomy. ABRA was added and OA was closed. No hernia developed at 10-month follow-up period. Conclusion. NPT application in septic OA patient may gain time to patient until adequate source control could be achieved. Using ABRA in conjunction with NPT increases the fascial closure rate in infected OA patient. PMID:27006853

  6. Management of a Septic Open Abdomen Patient with Spontaneous Jejunal Perforation after Emergent C/S with Confounding Factor of Mild Acute Pancreatitis.

    PubMed

    Yetisir, Fahri; Sarer, Akgün Ebru; Acar, Hasan Zafer; Osmanoglu, Gokhan; Özer, Mehmet; Yaylak, Faik

    2016-01-01

    Introduction. We report the management of a septic Open Abdomen (OA) patient by the help of negative pressure therapy (NPT) and abdominal reapproximation anchor (ABRA) system in pregnant woman with spontaneous jejunal perforation after emergent cesarean section (C/S) with confounding factor of mild acute pancreatitis (AP). Presentation of Case. A 29-year-old and 34-week pregnant woman with AP underwent C/S. She was arrested after anesthesia induction and responded to cardiopulmonary resuscitation (CPR). There were only ash-colored serosanguinous fluid within abdomen during C/S. After C/S, she was transferred to intensive care unit (ICU) with vasopressor support. On postoperative 1st day, she underwent reoperation due to fecal fluid coming near the drainage. Leakage point could not be identified exactly and operation had to be deliberately abbreviated due to hemodynamic instability. NPT was applied. Two days later source control was provided by conversion of enteroatmospheric fistula (EAF) to jejunostomy. ABRA was added and OA was closed. No hernia developed at 10-month follow-up period. Conclusion. NPT application in septic OA patient may gain time to patient until adequate source control could be achieved. Using ABRA in conjunction with NPT increases the fascial closure rate in infected OA patient. PMID:27006853

  7. [The role of jejunal feeding in the treatment of acute necrotizing pancreatitis and in recurrence of chronic pancreatitis with severe necrosis].

    PubMed

    Hamvas, J; Pap, A

    1998-04-19

    Acute necrotising is the most serious form of pancreatic inflammatory diseases leading to multiorgan failure and high (15-20%) mortality. The poor nutritional and metabolic condition of the patient and secondary bacterial translocation further rise the mortality. A recently introduced method of continuous nasojejunal feeding putting the pancreas into rest with basal pattern of secretion resulted in lower mortality rate by using adequate nutrition into the second loop of jejunum bypassing duodenopancreatic stimulations via an endoscopically placed feeding tube. The better nutritional and immunological states of the patients, the restored absorption and intestinal motility promote the recovery of pancreatitis, prevent bacterial translocation, resulting in time and in financial spares. Although surgery is occasionally inevitable because of progression of pancreatitis, nasojejunal feeding improves the general condition of patients more efficiently than parenteral nutrition and makes the scheduling of the operation optimal. The authors retrospectively analyse the results of treatment in 56 patients suffering from acute necrotising pancreatitis, as well as in 30 patients with chronic pancreatitis accompanied with more than 20% of necrosis in the pancreas and admitted to their gastroenterological medical department during 5 years. The effect of parenteral nutrition were less beneficial than that of jejunal feeding regarding the mortality and the necessity of operative interventions. Chronic pancreatitis with severe necrosis behaved similarly to the acute necrotising pancreatitis. The continuous nasojejunal feeding seems to be a promising new method for acute necrotising pancreatitis preventing complications and severe catabolic state of the disease by a cost--effective manner.

  8. Stellar Rotation Effects in Polarimetric Microlensing

    NASA Astrophysics Data System (ADS)

    Sajadian, Sedighe

    2016-07-01

    It is well known that the polarization signal in microlensing events of hot stars is larger than that of main-sequence stars. Most hot stars rotate rapidly around their stellar axes. The stellar rotation creates ellipticity and gravity-darkening effects that break the spherical symmetry of the source's shape and the circular symmetry of the source's surface brightness respectively. Hence, it causes a net polarization signal for the source star. This polarization signal should be considered in polarimetric microlensing of fast rotating stars. For moderately rotating stars, lensing can magnify or even characterize small polarization signals due to the stellar rotation through polarimetric observations. The gravity-darkening effect due to a rotating source star creates asymmetric perturbations in polarimetric and photometric microlensing curves whose maximum occurs when the lens trajectory crosses the projected position of the rotation pole on the sky plane. The stellar ellipticity creates a time shift (i) in the position of the second peak of the polarimetric curves in transit microlensing events and (ii) in the peak position of the polarimetric curves with respect to the photometric peak position in bypass microlensing events. By measuring this time shift via polarimetric observations of microlensing events, we can evaluate the ellipticity of the projected source surface on the sky plane. Given the characterizations of the FOcal Reducer and low dispersion Spectrograph (FORS2) polarimeter at the Very Large Telescope, the probability of observing this time shift is very small. The more accurate polarimeters of the next generation may well measure these time shifts and evaluate the ellipticity of microlensing source stars.

  9. Adaptation in a rotating artificial gravity environment

    NASA Technical Reports Server (NTRS)

    Lackner, J. R.; DiZio, P.

    1998-01-01

    The centripetal force generated by a rotating space vehicle is a potential source of artificial gravity. Minimizing the cost of such a vehicle dictates using the smallest radius and highest rotation rate possible, but head movements made at high rotation rates generate disorienting, nauseogenic cross-coupled semicircular canal stimulation. Early studies suggested 3 or 4 rpm as the highest rate at which humans could adapt to this vestibular stimulus. These studies neglected the concomitant Coriolis force actions on the head/neck system. We assessed non-vestibular Coriolis effects by measuring arm and leg movements made in the center of a rotating room turning at 10 rpm and found that movement endpoints and trajectories are initially deviated; however, subjects readily adapt with 10-20 additional movements, even without seeing their errors. Equilibrium point theories of motor control errantly predict that Coriolis forces will not cause movement endpoint errors so that subjects will not have to adapt their reaching movements during rotation. Adaptation of movement trajectory acquired during Coriolis force perturbations of one arm transfers to the unexposed arm but there is no intermanual transfer of endpoint adaptation indicating that neuromotor representations of movement endpoint and trajectory are separable and can adapt independently, also contradictory to equilibrium point theories. Touching a surface at the end of reaching movements is required for complete endpoint adaptation in darkness but trajectory adapts completely with or without terminal contact. We have also made the first kinematic measurements of unconstrained head movements during rotation, these movements show rapid adaptation to Coriolis force perturbations. Our results point to methods for achieving full compensation for rotation up to 10 rpm. Copyright 1998 Published by Elsevier Science B.V.

  10. Adaptation in a rotating artificial gravity environment.

    PubMed

    Lackner, J R; DiZio, P

    1998-11-01

    The centripetal force generated by a rotating space vehicle is a potential source of artificial gravity. Minimizing the cost of such a vehicle dictates using the smallest radius and highest rotation rate possible, but head movements made at high rotation rates generate disorienting, nauseogenic cross-coupled semicircular canal stimulation. Early studies suggested 3 or 4 rpm as the highest rate at which humans could adapt to this vestibular stimulus. These studies neglected the concomitant Coriolis force actions on the head/neck system. We assessed non-vestibular Coriolis effects by measuring arm and leg movements made in the center of a rotating room turning at 10 rpm and found that movement endpoints and trajectories are initially deviated; however, subjects readily adapt with 10-20 additional movements, even without seeing their errors. Equilibrium point theories of motor control errantly predict that Coriolis forces will not cause movement endpoint errors so that subjects will not have to adapt their reaching movements during rotation. Adaptation of movement trajectory acquired during Coriolis force perturbations of one arm transfers to the unexposed arm but there is no intermanual transfer of endpoint adaptation indicating that neuromotor representations of movement endpoint and trajectory are separable and can adapt independently, also contradictory to equilibrium point theories. Touching a surface at the end of reaching movements is required for complete endpoint adaptation in darkness but trajectory adapts completely with or without terminal contact. We have also made the first kinematic measurements of unconstrained head movements during rotation, these movements show rapid adaptation to Coriolis force perturbations. Our results point to methods for achieving full compensation for rotation up to 10 rpm. PMID:9795214

  11. The rotation of Titan and Ganymede

    NASA Astrophysics Data System (ADS)

    Van Hoolst, Tim; Coyette, Alexis; Baland, Rose-Marie; Trinh, Antony

    2016-10-01

    The rotation rates of Titan and Ganymede, the largest satellites of Saturn and Jupiter, are on average equal to their orbital mean motion. Here we discuss small deviations from the average rotation for both satellites and evaluate the polar motion of Titan induced by its surface fluid layers. We examine different causes at various time scales and assess possible consequences and the potential of using librations and polar motion as probes of the interior structure of the satellites.The rotation rate of Titan and Ganymede cannot be constant on the orbital time scale as a result of the gravitational torque of the central planet acting on the satellites. Titan is moreover expected to show significant polar motion and additional variations in the rotation rate due to angular momentum exchange with the atmosphere, mainly at seasonal periods. Observational evidence for deviations from the synchronous state has been reported several times for Titan but is unfortunately inconclusive. The measurements of the rotation variations are based on determinations of the shift in position of Cassini radar images taken during different flybys. The ESA JUICE (JUpiter ICy moons Explorer) mission will measure the rotation variations of Ganymede during its orbital phase around the satellite starting in 2032.We report on different theoretical aspects of the librations and polar motion. We consider the influence of the rheology of the ice shell and take into account Cassini measurements of the external gravitational field and of the topography of Titan and similar Galileo data about Ganymede. We also evaluate the librations and polar motion induced by Titan's hydrocarbon seas and use the most recent results of Titan's atmosphere dynamics. We finally evaluate the potential of rotation variations to constrain the satellite's interior structure, in particular its ice shell and ocean.

  12. Effects of stage of gestation and nutrient restriction during early to mid-gestation on maternal and fetal visceral organ mass and indices of jejunal growth and vascularity in beef cows.

    PubMed

    Meyer, A M; Reed, J J; Vonnahme, K A; Soto-Navarro, S A; Reynolds, L P; Ford, S P; Hess, B W; Caton, J S

    2010-07-01

    The objectives were to evaluate effects of maternal nutrient restriction and stage of gestation on maternal and fetal visceral organ mass and indices of jejunal growth and vascularity in beef cows. Thirty multiparous beef cows (BW = 571 +/- 63 kg; BCS = 5.4 +/- 0.7) carrying female fetuses (d 30 of gestation) were allocated to receive a diet of native grass hay (CON; 12.1% CP, 70.7% IVDMD, DM basis) to meet NRC recommendations for BW gain during early gestation or a nutrient-restricted diet of millet straw (NR; 9.9% CP, 54.5% IVDMD, DM basis) to provide 68.1% of NE(m) and 86.7% of MP estimated requirements. On d 125 of gestation, 10 CON and 10 NR cows were killed and necropsied. Five remaining CON cows received the CON diet, and 5 NR cows were realimented with a concentrate supplement (13.2% CP, 77.6% IVDMD, DM basis) and the CON hay to achieve a BCS similar to CON cows by d 220 of gestation. Remaining cows were necropsied on d 245 of gestation. Cow BW and eviscerated BW (EBW) were less (P < 0.01) for NR than CON at d 125 but did not differ (P > 0.63) at d 245. Cows fed the CON diet had greater (P < 0.09) total gastrointestinal (GI) tract, omasal, and pancreatic weights. Stomach complex, ruminal, and liver weights were greater for CON than NR cows (P < 0.09) on d 125. Total GI, stomach complex, and pancreatic weights increased (P < 0.001) with day of gestation. Restricted cows had decreased (P = 0.09) duodenal RNA:DNA compared with CON. Duodenal DNA was less (P = 0.01) and jejunal RNA:DNA (P = 0.09) was greater for cows at d 125 vs. 245. Cow jejunal capillary area density increased with day of gestation (P = 0.02). Fetal BW and EBW were unaffected by dietary treatment (P > or = 0.32). Total GI tract and all components increased in mass with day of gestation (P < 0.001). Fetuses from NR dams had greater (P = 0.003) reticular mass at d 245 than CON fetuses. Fetuses from NR cows had greater (P = 0.02) percent jejunal proliferation at d 125 and greater (P = 0.03) total

  13. Turbulent flow and heat transfer in rotating channels and tubes

    NASA Astrophysics Data System (ADS)

    Mitiakov, V. Y.; Petropavlovskii, R. R.; Ris, V. V.; Smirnov, E. M.; Smirnov, S. A.

    This document is a reduction of the author's experimental results on turbulent flow characteristics and heat transfer in rotating channels whose axes are parallel to the plane of rotation. Substantial dissimilarities of longitudinal velocity field profile and pulsational characteristics are caused by effects of stabilization and destabilization and secondary flow production. Local heat transfer coefficients vary over the perimeter of the tube section connecting detected flow peculiarities. It is shown that the increase in rotational intensity caused an increase in the relative dissimilarity of the local heat transfer coefficients and increased their mean value.

  14. Position, rotation, and intensity invariant recognizing method

    DOEpatents

    Ochoa, E.; Schils, G.F.; Sweeney, D.W.

    1987-09-15

    A method for recognizing the presence of a particular target in a field of view which is target position, rotation, and intensity invariant includes the preparing of a target-specific invariant filter from a combination of all eigen-modes of a pattern of the particular target. Coherent radiation from the field of view is then imaged into an optical correlator in which the invariant filter is located. The invariant filter is rotated in the frequency plane of the optical correlator in order to produce a constant-amplitude rotational response in a correlation output plane when the particular target is present in the field of view. Any constant response is thus detected in the output plane to determine whether a particular target is present in the field of view. Preferably, a temporal pattern is imaged in the output plane with a optical detector having a plurality of pixels and a correlation coefficient for each pixel is determined by accumulating the intensity and intensity-square of each pixel. The orbiting of the constant response caused by the filter rotation is also preferably eliminated either by the use of two orthogonal mirrors pivoted correspondingly to the rotation of the filter or the attaching of a refracting wedge to the filter to remove the offset angle. Detection is preferably performed of the temporal pattern in the output plane at a plurality of different angles with angular separation sufficient to decorrelate successive frames. 1 fig.

  15. COUNTER-ROTATION IN RELATIVISTIC MAGNETOHYDRODYNAMIC JETS

    SciTech Connect

    Cayatte, V.; Sauty, C.; Vlahakis, N.; Tsinganos, K.; Matsakos, T.; Lima, J. J. G.

    2014-06-10

    Young stellar object observations suggest that some jets rotate in the opposite direction with respect to their disk. In a recent study, Sauty et al. showed that this does not contradict the magnetocentrifugal mechanism that is believed to launch such outflows. Motion signatures that are transverse to the jet axis, in two opposite directions, have recently been measured in M87. One possible interpretation of this motion is that of counter-rotating knots. Here, we extend our previous analytical derivation of counter-rotation to relativistic jets, demonstrating that counter-rotation can indeed take place under rather general conditions. We show that both the magnetic field and a non-negligible enthalpy are necessary at the origin of counter-rotating outflows, and that the effect is associated with a transfer of energy flux from the matter to the electromagnetic field. This can be realized in three cases: if a decreasing enthalpy causes an increase of the Poynting flux, if the flow decelerates, or if strong gradients of the magnetic field are present. An illustration of the involved mechanism is given by an example of a relativistic magnetohydrodynamic jet simulation.

  16. Rotation curves of ultralight BEC dark matter halos with rotation

    NASA Astrophysics Data System (ADS)

    Guzmán, F. S.; Lora-Clavijo, F. D.

    2015-03-01

    We study the rotation curves of ultralight BEC dark matter halos. These halos are long lived solutions of initially rotating BEC fluctuations. In order to study the implications of the rotation characterizing these long-lived configurations we consider the particular case of a boson mass and no self-interaction. We find that these halos successfully fit samples of rotation curves of LSB galaxies.

  17. Wave-driven Rotation in Supersonically Rotating Mirrors

    SciTech Connect

    A. Fetterman and N.J. Fisch

    2010-02-15

    Supersonic rotation in mirrors may be produced by radio frequency waves. The waves produce coupled diffusion in ion kinetic and potential energy. A population inversion along the diffusion path then produces rotation. Waves may be designed to exploit a natural kinetic energy source or may provide the rotation energy on their own. Centrifugal traps for fusion and isotope separation may benefit from this wave-driven rotation.

  18. Rotating bacteria aggregate into active crystals

    NASA Astrophysics Data System (ADS)

    Petroff, Alexander; Wu, Xiao-Lun; Libchaber, Albert

    2014-11-01

    The dynamics of many microbial ecosystems are determined not only by the response of individual bacteria to their chemical and physical environments but also the dynamics that emerge from interactions between cells. Here we investigate the collective dynamics displayed by communities of Thiovulum majus, one of the fastest known bacteria. We observe that when these bacteria swim close to a microscope cover slip, the cells spontaneously aggregate into a visually-striking two-dimensional hexagonal lattice of rotating cells. Each cell in an aggregate rotates its flagella, exerting a force that pushes the cell into the cover slip and a torque that causes the cell to rotate. As cells rotate against their neighbors, they exert forces and torques on the aggregate that cause the crystal to move and cells to hop to new positions in the lattice. We show how these dynamics arises from hydrodynamic and surface forces between cells. We derive the equations of motion for an aggregate, show that this model reproduces many aspects of the observed dynamics, and discuss the stability of these and similar active crystals. Finally, we discuss the ecological significance of this behavior to understand how the ability to aggregate into these communities may have evolved.

  19. Rotating Bacteria Aggregate into Active Crystals

    NASA Astrophysics Data System (ADS)

    Petroff, A. P.; Wu, X. L.; Libchaber, A.

    2014-12-01

    The dynamics of many microbial ecosystems are determined not only by the response of individual bacteria to their chemical and physical environments but also the dynamics that emerge from interactions between cells. Here we investigate collective dynamics displayed by communities of Thiovulum majus, one of the fastest known bacteria. We observe that when these bacteria swim close to a microscope cover slip, the cells spontaneously aggregate into a visually-striking, two-dimensional hexagonal lattice of rotating cells. Each cell in an aggregate rotates its flagella, exerting a force that pushes the cell into the cover slip and a torque that causes the cell to rotate. As cells rotate against their neighbors, they exert forces and torques on the aggregate that cause the crystal to move and cells to hop to new positions in the lattice. We show how these dynamics arise from hydrodynamic and surface forces between cells. We derive the equations of motion for an aggregate, show that this model reproduces many aspects of the observed dynamics, and discuss the stability of these and similar active crystals. Finally, we discuss the ecological significance of this behavior to understand how the ability to aggregate into these communities may have evolved.

  20. System for automatically aligning a support roller system under a rotating body

    DOEpatents

    Singletary, B.H.

    1982-07-21

    Two support rings on a rotatable drum respectively engage conically tapered end surfaces of support rollers mounted on pivot universally relative to its axis of rotation and translate therealong. Rotation of the drum on differential conical support roller diameters causes pivotal steering and axial translation of support roller until roller is centered on support rings.

  1. System for automatically aligning a support roller system under a rotating body

    DOEpatents

    Singletary, B. Huston

    1983-01-01

    Two support rings on a rotatable drum respectively engage conically tapered nd surfaces of support rollers mounted on pivot universally relative to its axis of rotation and translate therealong. Rotation of the drum on differential conical support roller diameters causes pivotal steering and axial translation of support roller until roller is centered on support rings.

  2. Suppressing Permutations or Rigid Planar Rotations: A Remedy against Nonoptimal Varimax Rotations.

    ERIC Educational Resources Information Center

    Berge, Jos M. F. ten

    1995-01-01

    In Varimax rotation, permutations and reflections can give rise to the phenomenon that certain pairs of columns are consistently skipped in the iterative process, causing Varimax to terminate at a nonstationary point. This skipping phenomenon is demonstrated, and how to prevent it is described. (SLD)

  3. On the rotating Letelier spacetime

    NASA Astrophysics Data System (ADS)

    Barbosa, D.; Bezerra, V. B.

    2016-11-01

    We construct the solution corresponding to a rotating black hole surrounded by a cloud of strings (Rotating Letelier spacetime) from its nonrotating counterpart (Letelier spacetime) by applying a method of coordinate complexification developed by Newman and Janis.

  4. Quantal radiation from macroscopic rotation

    NASA Astrophysics Data System (ADS)

    Strutinsky, V.; Plujko, V.

    1988-09-01

    Macroscopic rotation of deformed excited nuclei may under certain conditions be accompanied by radiation of quasi-discrete gamma rays which resemble the cascade of transitions between nuclear rotational states.

  5. Rotational spectrum of tryptophan.

    PubMed

    Sanz, M Eugenia; Cabezas, Carlos; Mata, Santiago; Alonso, Josè L

    2014-05-28

    The rotational spectrum of the natural amino acid tryptophan has been observed for the first time using a combination of laser ablation, molecular beams, and Fourier transform microwave spectroscopy. Independent analysis of the rotational spectra of individual conformers has conducted to a definitive identification of two different conformers of tryptophan, with one of the observed conformers never reported before. The analysis of the (14)N nuclear quadrupole coupling constants is of particular significance since it allows discrimination between structures, thus providing structural information on the orientation of the amino group. Both observed conformers are stabilized by an O-H···N hydrogen bond in the side chain and a N-H···π interaction forming a chain that reinforce the strength of hydrogen bonds through cooperative effects.

  6. Rotatable seal assembly

    DOEpatents

    Logan, Clinton M.; Garibaldi, Jack L.

    1982-01-01

    An assembly is provided for rotatably supporting a rotor on a stator so that vacuum chambers in the rotor and stator remain in communication while the chambers are sealed from ambient air, which enables the use of a ball bearing or the like to support most of the weight of the rotor. The apparatus includes a seal device mounted on the rotor to rotate therewith, but shiftable in position on the rotor while being sealed to the rotor as by an O-ring. The seal device has a flat face that is biased towards a flat face on the stator, and pressurized air is pumped between the faces to prevent contact between them while spacing them a small distance apart to avoid the inflow of large amounts of air between the faces and into the vacuum chambers.

  7. Rotational spectrum of tryptophan

    SciTech Connect

    Sanz, M. Eugenia Cabezas, Carlos Mata, Santiago Alonso, Josè L.

    2014-05-28

    The rotational spectrum of the natural amino acid tryptophan has been observed for the first time using a combination of laser ablation, molecular beams, and Fourier transform microwave spectroscopy. Independent analysis of the rotational spectra of individual conformers has conducted to a definitive identification of two different conformers of tryptophan, with one of the observed conformers never reported before. The analysis of the {sup 14}N nuclear quadrupole coupling constants is of particular significance since it allows discrimination between structures, thus providing structural information on the orientation of the amino group. Both observed conformers are stabilized by an O–H···N hydrogen bond in the side chain and a N–H···π interaction forming a chain that reinforce the strength of hydrogen bonds through cooperative effects.

  8. Muon spin rotation studies

    NASA Technical Reports Server (NTRS)

    1984-01-01

    The bulk of the muon spin rotation research work centered around the development of the muon spin rotation facility at the Alternating Gradient Synchrotron (AGS) of Brookhaven National Laboratory (BNL). The collimation system was both designed and fabricated at Virginia State University. This improved collimation system, plus improvements in detectors and electronics enabled the acquisition of spectra free of background out to 15 microseconds. There were two runs at Brookhaven in 1984, one run was devoted primarily to beam development and the other run allowed several successful experiments to be performed. The effect of uniaxial strain on an Fe(Si) crystal at elevated temperature (360K) was measured and the results are incorporated herein. A complete analysis of Fe pulling data taken earlier is included.

  9. A Translational Polarization Rotator

    NASA Technical Reports Server (NTRS)

    Chuss, David T.; Wollack, Edward J.; Pisano, Giampaolo; Ackiss, Sheridan; U-Yen, Kongpop; Ng, Ming wah

    2012-01-01

    We explore a free-space polarization modulator in which a variable phase introduction between right- and left-handed circular polarization components is used to rotate the linear polarization of the outgoing beam relative to that of the incoming beam. In this device, the polarization states are separated by a circular polarizer that consists of a quarter-wave plate in combination with a wire grid. A movable mirror is positioned behind and parallel to the circular polarizer. As the polarizer-mirror distance is separated, an incident liear polarization will be rotated through an angle that is proportional to the introduced phase delay. We demonstrate a prototype device that modulates Stokes Q and U over a 20% bandwidth.

  10. Rotational Spectrum of Tryptophan

    NASA Astrophysics Data System (ADS)

    Sanz, M. Eugenia; Cabezas, Carlos; Mata, Santiago; Alonso, José L.

    2014-06-01

    The rotational spectrum of the natural amino acid tryptophan has been observed using a recently constructed LA-MB-FTMW spectrometer, specifically designed to optimize the detection of heavier molecules at a lower frequency range. Independent analyses of the rotational spectra of individual conformers have conducted to a definitive identification of two different conformers of tryptophan, with one of the observed conformers never reported before. The experimental values of the 14N nuclear quadrupole coupling constants have been found capital in the discrimination of the conformers. Both observed conformers are stabilized by a O-H\\cdotsN hydrogen bond in the side chain and a N-H\\cdotsπ interaction forming a chain that reinforces the strength of hydrogen bonds through cooperative effects.

  11. Solar Internal Rotation

    NASA Astrophysics Data System (ADS)

    Schou, J.; SOE Internal Rotation Team

    With the flood of high quality helioseismic data from the instruments on the SOHO spacecraft (MDI/VIRGO/GOLF) and ground based instruments (eg. GONG and LOWL) we have been able to get increasingly detailed information on the rotation and other large scale flows in the solar interior. In this talk I will discuss some of the highlights of what we have learned so far and what we may expect to learn in the near future. Among the recent advances have been tighter constraints on the tachocline at the bottom of the convection zone, detection of details in the surface rotation rate similar to the torsional oscillations found in the surface Doppler shift and helioseismic evidence for meridional flows. The MDI project is supported by NASA contract NAG5-3077 at Stanford University.

  12. Earth rotation and geodynamics

    NASA Astrophysics Data System (ADS)

    Bogusz, Janusz; Brzezinski, Aleksander; Kosek, Wieslaw; Nastula, Jolanta

    2015-12-01

    This paper presents the summary of research activities carried out in Poland in 2011-2014 in the field of Earth rotation and geodynamics by several Polish research institutions. It contains a summary of works on Earth rotation, including evaluation and prediction of its parameters and analysis of the related excitation data as well as research on associated geodynamic phenomena such as geocentre motion, global sea level change and hydrological processes. The second part of the paper deals with monitoring of geodynamic phenomena. It contains analysis of geodynamic networks of local, and regional scale using space (GNSS and SLR) techniques, Earth tides monitoring with gravimeters and water-tube hydrostatic clinometer, and the determination of secular variation of the Earth' magnetic field.

  13. Intestinal Rotation Anomalies.

    PubMed

    Pelayo, Juan Carlos; Lo, Andrea

    2016-07-01

    Intestinal rotation abnormality (IRA) predisposes to lethal midgut volvulus. An understanding of intestinal development illustrates the process of normal intestinal rotation and fixation. An appreciation of the clinical presentation and consequences of missed IRA will enhance clinical suspicion and timely evaluation. Selecting the appropriate imaging modality to diagnose IRA requires an understanding of the benefits and limitations of each. The Ladd's procedure continues to be the appropriate surgical treatment for IRA with or without volvulus. Laparoscopy has emerged as an option for the diagnosis and treatment of IRA. Populations in which IRA is always associated, but a Ladd's procedure rarely required, include patients with congenital diaphragmatic hernia and abdominal wall defects. Prevalence of IRA is higher in children with congenital heart disease and heterotaxy syndrome; asymptomatic patients require multidisciplinary consideration of the risks and benefits of screening for IRA, whether a Ladd's procedure is required, and the timing thereof. [Pediatr Ann. 2016;45(7):e247-e250.]. PMID:27403672

  14. A call for rotators

    NASA Astrophysics Data System (ADS)

    Mountain, Gregory

    “Needed: highly motivated geoscientists willing to slow the pace of their research for 1-2 years while managing federal government support of their discipline. Assured: change of perspective; no change in pay. Contact your National Science Foundation Program Director for details.—No, this isn't an NSF job announcement; this is an open letter to members of the Earth science community from a recently “retired” NSF rotator concerned by the small number of researchers interested in a Washington tour. I learned firsthand the extent to which an individual in this position is entrusted with decision-making powers, and as a result, I believe that each of us in the research community should feel responsible for ensuring that highly qualified people serve as rotators.

  15. Broadband Rotational Spectroscopy

    NASA Astrophysics Data System (ADS)

    Pate, Brooks

    2014-06-01

    The past decade has seen several major technology advances in electronics operating at microwave frequencies making it possible to develop a new generation of spectrometers for molecular rotational spectroscopy. High-speed digital electronics, both arbitrary waveform generators and digitizers, continue on a Moore's Law-like development cycle that started around 1993 with device bandwidth doubling about every 36 months. These enabling technologies were the key to designing chirped-pulse Fourier transform microwave (CP-FTMW) spectrometers which offer significant sensitivity enhancements for broadband spectrum acquisition in molecular rotational spectroscopy. A special feature of the chirped-pulse spectrometer design is that it is easily implemented at low frequency (below 8 GHz) where Balle-Flygare type spectrometers with Fabry-Perot cavity designs become technologically challenging due to the mirror size requirements. The capabilities of CP-FTMW spectrometers for studies of molecular structure will be illustrated by the collaborative research effort we have been a part of to determine the structures of water clusters - a project which has identified clusters up to the pentadecamer. A second technology trend that impacts molecular rotational spectroscopy is the development of high power, solid state sources in the mm-wave/THz regions. Results from the field of mm-wave chirped-pulse Fourier transform spectroscopy will be described with an emphasis on new problems in chemical dynamics and analytical chemistry that these methods can tackle. The third (and potentially most important) technological trend is the reduction of microwave components to chip level using monolithic microwave integrated circuits (MMIC) - a technology driven by an enormous mass market in communications. Some recent advances in rotational spectrometer designs that incorporate low-cost components will be highlighted. The challenge to the high-resolution spectroscopy community - as posed by Frank De

  16. Rotating housing turbine

    DOEpatents

    Allouche, Erez; Jaganathan, Arun P.

    2016-10-11

    The invention is a new turbine structure having a housing that rotates. The housing has a sidewall, and turbine blades are attached to a sidewall portion. The turbine may be completely open in the center, allowing space for solids and debris to be directed out of the turbine without jamming the spinning blades/sidewall. The turbine may be placed in a generator for generation of electrical current.

  17. Rotating Vessels for Growing Protein Crystals

    NASA Technical Reports Server (NTRS)

    Cottingham, Paul

    2005-01-01

    Rotating vessels have been proposed as means of growing larger, more nearly uniform protein crystals than would otherwise be possible in the presence of normal Earth gravitation. Heretofore, nonrotating vessels have been used. It is difficult to grow high-quality protein crystals in the terrestrial gravitational field because of convection plumes created by the interaction between gravitation and density gradients in protein-solution depletion layers around growing crystals. The density gradients and the associated convection plumes cause the surfaces of growing crystals to be exposed to nonuniform solution densities, thereby causing the crystals to form in irregular shapes. The microgravitational environment of outer space has been utilized to eliminate gravitation-induced convection, but this approach is generally not favorable because of the high cost and limited availability of space flight. The use of a rotating vessel according to the proposal is intended to ameliorate the effects of gravitation and the resultant convection, relative to the corresponding effects in a non-rotating vessel. The rotation would exert an averaging effect over time, distributing the convective force on the depletion layer. Therefore, the depletion layer would be more nearly uniform and, as a result, the growing crystal would be more nearly perfect. The proposal admits of variations (see figure), including the following: The growing crystal could be rotated about its own central axis or an external axis. The crystal-growth vessel could be of any of various shapes, including cylindrical, hemispherical, conical, and combinations thereof. The crystal-growth vessel could be suspended in a viscous fluid in an outer vessel to isolate the growing crystal from both ambient vibrations and vibrations induced by a mechanism that drives the rotation. The rotation could be coupled to the crystal-growth vessel by viscous or magnetic means. The crystal-growth vessel could be supported within the

  18. Chaotic Rotation of Nereid

    NASA Technical Reports Server (NTRS)

    Dobrovolskis, Anthony R.; Cuzzi, Jeffrey N. (Technical Monitor)

    1995-01-01

    The shape and spin of Neptune's outermost satellite Nereid are still unknown. Ground-based photometry indicates large brightness variations, but different observers report very different lightcurve amplitudes and periods. On the contrary, Voyager 2 images spanning 12 days show no evidence of variations greater than 0.1 mag. The latter suggest either that Nereid is nearly spherical, or that it is rotating slowly. We propose that tides have already despun Nereid's rotation to a period of a few weeks, during the time before the capture of Triton when Nereid was closer to Neptune. Since Nereid reached its present orbit, tides have further despun Nereid to a period on the order of a month. For Nereid's orbital eccentricity of 0.75, tidal evolution ceases when the spin period is still approximately 1/8 of the orbital period. Furthermore, the synchronous resonance becomes quite weak for such high eccentricities, along with other low-order spin orbit commensurabilities. In contrast, high-order resonances become very strong particularly the 6:1, 6.5:1, 7:1, 7.5:1, and 8:1 spin states. If Nereid departs by more than approximately 1% from a sphere, however, these resonances overlap, generating chaos. Our simulations show that Nereid is likely to be in chaotic rotation for any spin period longer than about 2 weeks.

  19. Bioreactor rotating wall vessel

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Cell constructs grown in a rotating bioreactor on Earth (left) eventually become too large to stay suspended in the nutrient media. In the microgravity of orbit, the cells stay suspended. Rotation then is needed for gentle stirring to replenish the media around the cells.

  20. Impingement is not impingement: the case for calling it "Rotator Cuff Disease".

    PubMed

    McFarland, Edward G; Maffulli, Nicola; Del Buono, Angelo; Murrell, George A C; Garzon-Muvdi, Juan; Petersen, Steve A

    2013-07-01

    Historically, many causes have been proposed for rotator cuff conditions. The most prevalent theory is that the rotator cuff tendons, especially the supraspinatus, make contact with the acromion and coracoacromial ligament, resulting in pain and eventual tearing of the tendon. However, more recent evidence suggests that this concept does not explain the changes in rotator cuff tendons with age. The role of acromioplasty and coracoacromial ligament release in the treatment of rotator cuff disease has become questioned. Evidence now suggests that tendinopathy associated with aging may be a predominant factor in the development of rotator cuff degeneration. We propose that the overwhelming evidence favors factors other than "impingement" as the major cause of rotator cuff disease and that a paradigm shift in the way the development of rotator cuff pathology is conceptualized allows for a more comprehensive approach to the care of the patient with rotator cuff disease. PMID:24367779

  1. Impingement is not impingement: the case for calling it “Rotator Cuff Disease”

    PubMed Central

    McFarland, Edward G.; Maffulli, Nicola; Del Buono, Angelo; Murrell, George A. C.; Garzon-Muvdi, Juan; Petersen, Steve A.

    2013-01-01

    Summary Historically, many causes have been proposed for rotator cuff conditions. The most prevalent theory is that the rotator cuff tendons, especially the supraspinatus, make contact with the acromion and coracoacromial ligament, resulting in pain and eventual tearing of the tendon. However, more recent evidence suggests that this concept does not explain the changes in rotator cuff tendons with age. The role of acromioplasty and coracoacromial ligament release in the treatment of rotator cuff disease has become questioned. Evidence now suggests that tendinopathy associated with aging may be a predominant factor in the development of rotator cuff degeneration. We propose that the overwhelming evidence favors factors other than “impingement” as the major cause of rotator cuff disease and that a paradigm shift in the way the development of rotator cuff pathology is conceptualized allows for a more comprehensive approach to the care of the patient with rotator cuff disease. PMID:24367779

  2. On the Product of Rotations

    ERIC Educational Resources Information Center

    Trenkler, G.; Trenkler, D.

    2008-01-01

    Using the elementary tools of matrix theory, we show that the product of two rotations in the three-dimensional Euclidean space is a rotation again. For this purpose, three types of rotation matrices are identified which are of simple structure. One of them is the identity matrix, and each of the other two types can be uniquely characterized by…

  3. Rotating plug bearing and seal

    DOEpatents

    Wade, Elman E.

    1977-01-01

    A bearing and seal structure for nuclear reactors utilizing rotating plugs above the nuclear reactor vessel. The structure permits lubrication of bearings and seals of the rotating plugs without risk of the lubricant draining into the reactor vessel below. The structure permits lubrication by utilizing a rotating outer race bearing.

  4. Doppler observations of solar rotation

    NASA Technical Reports Server (NTRS)

    Scherrer, P. H.; Wilcox, J. M.

    1980-01-01

    Daily observations of the photospheric equatorial rotation rate using the Doppler effect are made at the Stanford Solar Observatory. These observations show no variations in the rotation rate that exceed the observational error of about 1%. The average rotation rate is indistinguishable from that of sunspots and large-scale magnetic field structures.

  5. Doppler observations of solar rotation

    NASA Technical Reports Server (NTRS)

    Scherrer, P. H.

    1980-01-01

    Daily observations of the photospheric equatorial rotation rate using the Doppler effect mode at the Sanford Solar Observatory are presented. These observations show no variations in the rotation rate that exceed the observational error of about one percent. The average rotation rate is indistinguishable from that of sunspots and large scale magnetic field structures.

  6. Quantum Localization in Laser-Driven Molecular Rotation

    NASA Astrophysics Data System (ADS)

    Averbukh, Ilya

    2016-05-01

    Recently we predicted that several celebrated solid state quantum localization phenomena - Anderson localization, Bloch oscillations, and Tamm-Shockley surface states - may manifest themselves in the rotational dynamics of laser-kicked molecules. In this talk, I will present these new rotational effects in a gas of linear molecules subject to a moderately long periodic train of femtosecond laser pulses. A small detuning of the train period from the rotational revival time causes Anderson localization in the angular momentum space above some critical value of J - the Anderson wall. This wall marks an impenetrable border stopping any further rotational excitation. Below the Anderson wall, the rotational excitation oscillates with the number of pulses due to a mechanism similar to Bloch oscillations in crystalline solids. I will present the results of the first experimental observation of the laser-induced rotational Bloch oscillations in molecular nitrogen at ambient conditions (Stanford & Weizmann, 2015). We will also discuss the prospects of observing the rotational analogues of the Tamm surface states in a similar experimental setup. Our results offer laser-driven molecular rotation as a new platform for studies on the localization phenomena in quantum transport. These effects are important for many processes involving highly excited rotational states, including coherent optical manipulations in molecular mixtures, and propagation of powerful laser pulses in atmosphere.

  7. Is rotating between static and dynamic work beneficial for our fatigue state?

    PubMed

    Luger, Tessy; Bosch, Tim; Hoozemans, Marco J M; Veeger, DirkJan H E J; de Looze, Michiel P

    2016-06-01

    Shoulder disorders comprise a large part of work-related musculoskeletal disorders. Risk factors, such as repetitiveness and monotony, may cause muscle fatigue and be attenuated by task rotation. We investigated rotation between a dynamic box-lifting task and a relatively static pick-and-place task and aimed to determine whether (1) a high rotation frequency leads to less fatigue development than a low rotation frequency, and (2) a self-selected rotation frequency leads to less fatigue development than imposed rotation frequencies. Ten participants performed four one-hour rotation schedules: two low frequency rotation schedules rotating at 30min, one high frequency rotation schedule rotating every sixth minute, and a self-selected rotation schedule. Borg, SOFI and electromyography of Trapezius and Deltoid subparts served as fatigue indicators. We found significant signs of fatigue for most schedules regarding the Borg and SOFI ratings and the M. Trapezius pars Descendens. Task rotation frequency had no significant effect on any of the outcome parameters, whereas the self-selected rotation schedule clearly resulted in less development of perceived fatigue than imposed schedules. In conclusion, we think that freedom of rotation has the greatest potential to attenuate potential development of musculoskeletal disorders and we require due caution with the use and interpretation of EMG indicators of fatigue.

  8. Observation of dust torus with poloidal rotation in direct current glow discharge plasma

    NASA Astrophysics Data System (ADS)

    Kaur, Manjit; Bose, Sayak; Chattopadhyay, P. K.; Sharma, Devendra; Ghosh, J.; Saxena, Y. C.

    2015-03-01

    Observation of dust cloud rotation in parallel-plate DC glow discharge plasma is reported here. The experiments are carried out at high pressures (˜130 Pa) with a metallic ring placed on the lower electrode (cathode). The dust cloud rotates poloidally in the vertical plane near the cathode surface. This structure is continuous toroidally. Absence of magnetic field rules out the possibility of E × B induced ion flow as the cause of dust rotation. The dust rotational structures exist even with water cooled cathode. Therefore, temperature gradient driven mechanisms, such as thermophoretic force, thermal creep flow, and free convection cannot be causing the observed dust rotation. Langmuir probe measurement reveals the existence of a sharp density gradient near the location of the rotating dust cloud. The gradient in the density, giving rise to a gradient in the ion drag force, has been identified as the principal cause behind the rotation of dust particles.

  9. Observation of dust torus with poloidal rotation in direct current glow discharge plasma

    SciTech Connect

    Kaur, Manjit Bose, Sayak; Chattopadhyay, P. K. Sharma, Devendra; Ghosh, J.; Saxena, Y. C.

    2015-03-15

    Observation of dust cloud rotation in parallel-plate DC glow discharge plasma is reported here. The experiments are carried out at high pressures (∼130 Pa) with a metallic ring placed on the lower electrode (cathode). The dust cloud rotates poloidally in the vertical plane near the cathode surface. This structure is continuous toroidally. Absence of magnetic field rules out the possibility of E × B induced ion flow as the cause of dust rotation. The dust rotational structures exist even with water cooled cathode. Therefore, temperature gradient driven mechanisms, such as thermophoretic force, thermal creep flow, and free convection cannot be causing the observed dust rotation. Langmuir probe measurement reveals the existence of a sharp density gradient near the location of the rotating dust cloud. The gradient in the density, giving rise to a gradient in the ion drag force, has been identified as the principal cause behind the rotation of dust particles.

  10. Translating Human Effective Jejunal Intestinal Permeability to Surface-Dependent Intrinsic Permeability: a Pragmatic Method for a More Mechanistic Prediction of Regional Oral Drug Absorption.

    PubMed

    Olivares-Morales, Andrés; Lennernäs, Hans; Aarons, Leon; Rostami-Hodjegan, Amin

    2015-09-01

    Regional intestinal effective permeability (P(eff)) values are key for the understanding of drug absorption along the whole length of the human gastrointestinal (GI) tract. The distal regions of the GI tract (i.e. ileum, ascending-transverse colon) represent the main sites for GI absorption when there is incomplete absorption in the upper GI tract, e.g. for modified release formulations. In this work, a new and pragmatic method for the estimation of (passive) intestinal permeability in the different intestinal regions is being proposed, by translating the observed differences in the available mucosal surface area along the human GI tract into corrections of the historical determined jejunal P(eff) values. These new intestinal P(eff) values or "intrinsic" P(eff)(P(eff,int)) were subsequently employed for the prediction of the ileal absorption clearance (CL(abs,ileum)) for a set of structurally diverse compounds. Additionally, the method was combined with a semi-mechanistic absorption PBPK model for the prediction of the fraction absorbed (f(abs)). The results showed that P(eff,int) can successfully be employed for the prediction of the ileal CL(abs) and the f(abs). P(eff,int) also showed to be a robust predictor of the f(abs) when the colonic absorption was allowed in the PBPK model, reducing the overprediction of f(abs) observed for lowly permeable compounds when using the historical P(eff) values. Due to its simplicity, this approach provides a useful alternative for the bottom-up prediction of GI drug absorption, especially when the distal GI tract plays a crucial role for a drug's GI absorption.

  11. Peptide Transporter 1 is Responsible for Intestinal Uptake of the Dipeptide Glycylsarcosine: Studies in Everted Jejunal Rings from Wild-type and Pept1 Null Mice

    PubMed Central

    Ma, Katherine; Hu, Yongjun; Smith, David E.

    2010-01-01

    The purpose of this study was to determine the relative importance of PEPT1 in the uptake of peptides/mimetics from mouse small intestine using glycylsarcosine (GlySar). After isolating jejunal tissue from wild-type and Pept1 null mice, 2-cm intestinal segments were everted and mounted on glass rods for tissue uptake studies. [14C]GlySar (4 μM) was studied as a function of time, temperature, sodium and pH, concentration, and potential inhibitors. Compared to wild-type animals, Pept1 null mice exhibited a 78% reduction of GlySar uptake at pH 6.0, 37°C. GlySar uptake showed pH dependence with peak values between pH 6.0-6.5 in wild-type animals, while no such tendency was observed in Pept1 null mice. GlySar exhibited Michaelis-Menten uptake kinetics and a minor nonsaturable component in wild-type animals. In contrast, GlySar uptake occurred by only a nonsaturable process in Pept1 null mice. GlySar uptake was significantly inhibited by dipeptides, aminocephalosporins, angiotensin-converting enzyme inhibitors, and the antiviral prodrug valacyclovir; these inhibitors had little, if any, effect on the uptake of GlySar in Pept1 null mice. The findings demonstrate that PEPT1 plays a critical role in the uptake of GlySar in jejunum, and suggest that PEPT1 is the major transporter responsible for the intestinal absorption of small peptides. PMID:20862774

  12. Isorotation and differential rotation in a magnetic mirror with imposed E Multiplication-Sign B rotation

    SciTech Connect

    Romero-Talamas, C. A.; Elton, R. C.; Young, W. C.; Reid, R.; Ellis, R. F.

    2012-07-15

    Doppler spectroscopy of helium impurities in the Maryland Centrifugal Experiment reveals the simultaneous existence of isorotating and differentially rotating magnetic surfaces. Differential rotation occurs at the innermost surfaces and is conjectured to cause plasma voltage oscillations of hundreds of kilohertz by periodically changing the current path inductance. High-speed images show the periodic expulsion of plasma near the mirror ends at the same frequencies. In spite of this, the critical ionization velocity limit is exceeded, with respect to the vacuum field definition, for at least 0.5 ms.

  13. Estimating extragalactic Faraday rotation

    NASA Astrophysics Data System (ADS)

    Oppermann, N.; Junklewitz, H.; Greiner, M.; Enßlin, T. A.; Akahori, T.; Carretti, E.; Gaensler, B. M.; Goobar, A.; Harvey-Smith, L.; Johnston-Hollitt, M.; Pratley, L.; Schnitzeler, D. H. F. M.; Stil, J. M.; Vacca, V.

    2015-03-01

    Observations of Faraday rotation for extragalactic sources probe magnetic fields both inside and outside the Milky Way. Building on our earlier estimate of the Galactic contribution, we set out to estimate the extragalactic contributions. We discuss the problems involved; in particular, we point out that taking the difference between the observed values and the Galactic foreground reconstruction is not a good estimate for the extragalactic contributions. We point out a degeneracy between the contributions to the observed values due to extragalactic magnetic fields and observational noise and comment on the dangers of over-interpreting an estimate without taking into account its uncertainty information. To overcome these difficulties, we develop an extended reconstruction algorithm based on the assumption that the observational uncertainties are accurately described for a subset of the data, which can overcome the degeneracy with the extragalactic contributions. We present a probabilistic derivation of the algorithm and demonstrate its performance using a simulation, yielding a high quality reconstruction of the Galactic Faraday rotation foreground, a precise estimate of the typical extragalactic contribution, and a well-defined probabilistic description of the extragalactic contribution for each data point. We then apply this reconstruction technique to a catalog of Faraday rotation observations for extragalactic sources. The analysis is done for several different scenarios, for which we consider the error bars of different subsets of the data to accurately describe the observational uncertainties. By comparing the results, we argue that a split that singles out only data near the Galactic poles is the most robust approach. We find that the dispersion of extragalactic contributions to observed Faraday depths is most likely lower than 7 rad/m2, in agreement with earlier results, and that the extragalactic contribution to an individual data point is poorly

  14. Rotational manipulation of single cells and organisms using acoustic waves.

    PubMed

    Ahmed, Daniel; Ozcelik, Adem; Bojanala, Nagagireesh; Nama, Nitesh; Upadhyay, Awani; Chen, Yuchao; Hanna-Rose, Wendy; Huang, Tony Jun

    2016-01-01

    The precise rotational manipulation of single cells or organisms is invaluable to many applications in biology, chemistry, physics and medicine. In this article, we describe an acoustic-based, on-chip manipulation method that can rotate single microparticles, cells and organisms. To achieve this, we trapped microbubbles within predefined sidewall microcavities inside a microchannel. In an acoustic field, trapped microbubbles were driven into oscillatory motion generating steady microvortices which were utilized to precisely rotate colloids, cells and entire organisms (that is, C. elegans). We have tested the capabilities of our method by analysing reproductive system pathologies and nervous system morphology in C. elegans. Using our device, we revealed the underlying abnormal cell fusion causing defective vulval morphology in mutant worms. Our acoustofluidic rotational manipulation (ARM) technique is an easy-to-use, compact, and biocompatible method, permitting rotation regardless of optical, magnetic or electrical properties of the sample under investigation. PMID:27004764

  15. Conformational Slippage Determines Rotational Frequency in Five-Component Nanorotors.

    PubMed

    Samanta, Soumen K; Rana, Anup; Schmittel, Michael

    2016-02-01

    Several five-component nanorotors ROT-3 that rotate at different rates were prepared by adding phenanthrolines of distinct lateral size as brake blocks to the four-component nanorotor ROT-2. The brake blocks interfere with the 180° rotor causing the rotational frequency to drop from 97 kHz to 5 kHz. The effect of the rotating brake blocks on the rotational frequency in ROT-3 is accurately predicted by a nanomechanical model called "conformational slippage". For quantification, the interaction of the brake blocks with the trajectory of the main rotator is gauged based on the number of interfering vs. non-interfering conformations as computed by PM6.

  16. Rotational manipulation of single cells and organisms using acoustic waves.

    PubMed

    Ahmed, Daniel; Ozcelik, Adem; Bojanala, Nagagireesh; Nama, Nitesh; Upadhyay, Awani; Chen, Yuchao; Hanna-Rose, Wendy; Huang, Tony Jun

    2016-01-01

    The precise rotational manipulation of single cells or organisms is invaluable to many applications in biology, chemistry, physics and medicine. In this article, we describe an acoustic-based, on-chip manipulation method that can rotate single microparticles, cells and organisms. To achieve this, we trapped microbubbles within predefined sidewall microcavities inside a microchannel. In an acoustic field, trapped microbubbles were driven into oscillatory motion generating steady microvortices which were utilized to precisely rotate colloids, cells and entire organisms (that is, C. elegans). We have tested the capabilities of our method by analysing reproductive system pathologies and nervous system morphology in C. elegans. Using our device, we revealed the underlying abnormal cell fusion causing defective vulval morphology in mutant worms. Our acoustofluidic rotational manipulation (ARM) technique is an easy-to-use, compact, and biocompatible method, permitting rotation regardless of optical, magnetic or electrical properties of the sample under investigation.

  17. Rotational Doppler effect in x-ray photoionization

    SciTech Connect

    Sun Yuping; Wang Chuankui; Gel'mukhanov, Faris

    2010-11-15

    The energy of the photoelectron experiences a red or blue Doppler shift when the molecule recedes from the detector or approaches him. This results in a broadening of the photoelectron line due to the translational thermal motion. However, the molecules also have rotational degrees of freedom and we show that the translational Doppler effect has its rotational counterpart. This rotational Doppler effect leads to an additional broadening of the spectral line of the same magnitude as the Doppler broadening caused by translational thermal motion. The rotational Doppler broadening as well as the rotational recoil broadening is sensitive to the molecular orbital from which the photoelectron is ejected. This broadening should be taken into account in analysis of x-ray photoemission spectra of super-high resolution and it can be directly observed using x-ray pump-probe spectroscopy.

  18. Rotational manipulation of single cells and organisms using acoustic waves

    PubMed Central

    Ahmed, Daniel; Ozcelik, Adem; Bojanala, Nagagireesh; Nama, Nitesh; Upadhyay, Awani; Chen, Yuchao; Hanna-Rose, Wendy; Huang, Tony Jun

    2016-01-01

    The precise rotational manipulation of single cells or organisms is invaluable to many applications in biology, chemistry, physics and medicine. In this article, we describe an acoustic-based, on-chip manipulation method that can rotate single microparticles, cells and organisms. To achieve this, we trapped microbubbles within predefined sidewall microcavities inside a microchannel. In an acoustic field, trapped microbubbles were driven into oscillatory motion generating steady microvortices which were utilized to precisely rotate colloids, cells and entire organisms (that is, C. elegans). We have tested the capabilities of our method by analysing reproductive system pathologies and nervous system morphology in C. elegans. Using our device, we revealed the underlying abnormal cell fusion causing defective vulval morphology in mutant worms. Our acoustofluidic rotational manipulation (ARM) technique is an easy-to-use, compact, and biocompatible method, permitting rotation regardless of optical, magnetic or electrical properties of the sample under investigation. PMID:27004764

  19. Magnetopause rotational forms

    NASA Technical Reports Server (NTRS)

    Sonnerup, B. U. O.; Ledley, B. G.

    1974-01-01

    Magnetic field data from the Goddard Space Flight Center magnetometer experiment on board Ogo 5 are analyzed by the minimum-variance technique for two magnetopause crossings, believed to provide the best evidence presently available of magnetopause rotational discontinuities. Approximate agreement with predictions from MHD and first-order orbit theory is found, but available low-energy electron data suggest the presence of significant non-MHD effects. The paper also illustrates an improved method for data interval selection, a new magnetopause hodogram representation, and the utility of data simulation.

  20. ROTATING PLASMA DEVICE

    DOEpatents

    Boyer, K.; Hammel, J.E.; Longmire, C.L.; Nagle, D.E.; Ribe, F.L.; Tuck, J.L.

    1961-10-24

    ABS>A method and device are described for obtaining fusion reactions. The basic concept is that of using crossed electric and magnetic fields to induce a plasma rotation in which the ionized particles follow a circumferential drift orbit on wldch a cyclotron mode of motion is superimposed, the net result being a cycloidal motion about the axis of symmetry. The discharge tube has a radial electric field and a longitudinal magnetic field. Mirror machine geometry is utilized. The device avoids reliance on the pinch effect and its associated instability problems. (AEC)

  1. Sample rotating turntable kit for infrared spectrometers

    DOEpatents

    Eckels, Joel Del; Klunder, Gregory L.

    2008-03-04

    An infrared spectrometer sample rotating turntable kit has a rotatable sample cup containing the sample. The infrared spectrometer has an infrared spectrometer probe for analyzing the sample and the rotatable sample cup is adapted to receive the infrared spectrometer probe. A reflectance standard is located in the rotatable sample cup. A sleeve is positioned proximate the sample cup and adapted to receive the probe. A rotator rotates the rotatable sample cup. A battery is connected to the rotator.

  2. Optical angular momentum in a rotating frame.

    PubMed

    Speirits, Fiona C; Lavery, Martin P J; Padgett, Miles J; Barnett, Stephen M

    2014-05-15

    It is well established that light carrying orbital angular momentum (OAM) can be used to induce a mechanical torque causing an object to spin. We consider the complementary scenario: will an observer spinning relative to the beam axis measure a change in OAM as a result of their rotational velocity? Remarkably, although a linear Doppler shift changes the linear momentum of a photon, the angular Doppler shift induces no change in the angular momentum. Further, we examine the rotational Doppler shift in frequency imparted to the incident light due to the relative motion of the beam with respect to the observer and consider what must happen to the measured wavelength if the speed of light c is to remain constant. We show specifically that the OAM of the incident beam is not affected by the rotating observer and that the measured wavelength is shifted by a factor equal and opposite to that of the frequency shift induced by the rotational Doppler effect. PMID:24978243

  3. Revealing cosmic rotation

    NASA Astrophysics Data System (ADS)

    Yadav, Amit P. S.; Shimon, Meir; Keating, Brian G.

    2012-10-01

    Cosmological Birefringence, a rotation of the polarization plane of radiation coming to us from distant astrophysical sources, may reveal parity violation in either the electromagnetic or gravitational sectors of the fundamental interactions in nature. Until only recently this phenomenon could be probed with only radio observations or observations at UV wavelengths. Recently, there is a substantial effort to constrain such nonstandard models using observations of the rotation of the polarization plane of cosmic microwave background (CMB) radiation. This can be done via measurements of the B-modes of the CMB or by measuring its TB and EB correlations which vanish in the standard model. In this paper we show that EB correlations-based estimator is the best for upcoming polarization experiments. The EB-based estimator surpasses other estimators because it has the smallest noise and of all the estimators is least affected by systematics. Current polarimeters are optimized for the detection of B-mode polarization from either primordial gravitational waves or by large-scale structures via gravitational lensing. In the paper we also study the optimization of CMB experiments for the detection of cosmological birefringence, in the presence of instrumental systematics, which by themselves are capable of producing EB correlations, potentially mimicking cosmological birefringence.

  4. Rotating drum filter

    DOEpatents

    Anson, Donald

    1990-01-01

    A perforated drum (10) rotates in a coaxial cylindrical housing (18) having three circumferential ports (19,22,23), and an axial outlet (24) at one end. The axis (11) is horizontal. A fibrous filter medium (20) is fed through a port (19) on or near the top of the housing (81) by a distributing mechanism (36) which lays a uniform mat (26) of the desired thickness onto the rotating drum (10). This mat (26) is carried by the drum (10) to a second port (23) through which dirty fluid (13) enters. The fluid (13) passes through the filter (26) and the cleaned stream (16) exits through the open end (15) of the drum (10) and the axial port (24) in the housing (18). The dirty filter material (20) is carried on to a third port (22) near the bottom of the housing (18) and drops into a receiver (31) from which it is continuously removed, cleaned (30), and returned (32) to the charging port (36) at the top. To support the filter mat, the perforated cylinder may carry a series of tines (40), shaped blades (41), or pockets, so that the mat (26) will not fall from the drum (10) prematurely. To minimize risk of mat failure, the fluid inlet port (23) may be located above the horizontal centerline (11).

  5. Digital rotation measurement unit

    DOEpatents

    Sanderson, S.N.

    1983-09-30

    A digital rotation indicator is disclosed for monitoring the position of a valve member having a movable actuator. The indicator utilizes mercury switches adapted to move in cooperation with the actuator. Each of the switches produces an output as it changes state when the actuator moves. A direction detection circuit is connected to the switches to produce a first digital signal indicative of the direction of rotation of the actuator. A count pulse generating circuit is also connected to the switches to produce a second digital pulse signal having count pulses corresponding to a change of state of any of the mercury switches. A reset pulse generating circuit is provided to generate a reset pulse each time a count pulse is generated. An up/down counter is connected to receive the first digital pulse signal and the second digital pulse signal and to count the pulses of the second digital pulse signal either up or down depending upon the instantaneous digital value of the first digital signal whereby a running count indicative of the movement of the actuator is maintained.

  6. Anderson wall and BLOCH oscillations in molecular rotation.

    PubMed

    Floß, Johannes; Averbukh, Ilya Sh

    2014-07-25

    We describe a universal behavior of linear molecules excited by a periodic train of short laser pulses under quantum resonance conditions. In a rigid rotor, the resonance causes an unlimited ballistic growth of the angular momentum. We show that the centrifugal distortion of rotating molecules eventually halts the growth, by causing Anderson localization beyond a critical value of the angular momentum--the Anderson wall. Its position solely depends on the molecular rotational constants and lies in the range of a few tens of ℏ. Below the wall, rotational excitation oscillates with the number of pulses due to a mechanism similar to Bloch oscillations in crystalline solids. We suggest optical experiments capable of observing the rotational Anderson wall and Bloch oscillations at near-ambient conditions with the help of existing laser technology.

  7. Rotator Cerclage Technique for Partial Rotator Cuff Ruptures

    PubMed Central

    Bozkurt, Murat; Firat, Ahmet; Gursoy, Safa; Akkaya, Mustafa

    2015-01-01

    The frequency of partial rotator cuff tears is gradually increasing because of the advancements in imaging methods and arthroscopy techniques. One of the repair techniques is repair of the partial rotator cuff tear by conversion to a full-thickness tear. Another technique, the transtendon technique, has some practical challenges and risks. We attempted to develop a practical and easy technique with low morbidity to repair partial tears called the rotator cerclage technique. PMID:26900559

  8. Visualizing rotations and composition of rotations with the Rodrigues vector

    NASA Astrophysics Data System (ADS)

    Valdenebro, Angel G.

    2016-11-01

    The purpose of this paper is to show that the mathematical treatment of three-dimensional rotations can be simplified, and its geometrical understanding improved, using the Rodrigues vector representation. We present a novel geometrical interpretation of the Rodrigues vector. Based on this interpretation and simple geometrical considerations, we derive the Euler-Rodrigues formula, Cayley’s rotation formula and the composition law for finite rotations. The level of this discussion should be suitable for undergraduate physics or engineering courses where rotations are discussed.

  9. Bifurcations of rotating waves in rotating spherical shell convection.

    PubMed

    Feudel, F; Tuckerman, L S; Gellert, M; Seehafer, N

    2015-11-01

    The dynamics and bifurcations of convective waves in rotating and buoyancy-driven spherical Rayleigh-Bénard convection are investigated numerically. The solution branches that arise as rotating waves (RWs) are traced by means of path-following methods, by varying the Rayleigh number as a control parameter for different rotation rates. The dependence of the azimuthal drift frequency of the RWs on the Ekman and Rayleigh numbers is determined and discussed. The influence of the rotation rate on the generation and stability of secondary branches is demonstrated. Multistability is typical in the parameter range considered.

  10. Purcell's ``rotator'': mechanical rotation at low Reynolds number

    NASA Astrophysics Data System (ADS)

    Dreyfus, R.; Baudry, J.; Stone, H. A.

    2005-09-01

    An object consisting of three spheres, linked like the spokes on a wheel, can undergo a net rotational movement when the relative positions of the spheres proceed through a four-step cycle. This rotational motion is the analogue of the two-hinged swimmer originally proposed by Purcell (1977), which has served as a prototype for mechanical implementations of swimming. We also note that the rotational motion analysed here may be useful in the design of micromachines and has similarities to molecular-scale rotational motors that have been identified recently.

  11. The role of sea ice in slowly rotating aquaplanet simulations

    NASA Astrophysics Data System (ADS)

    Salameh, Josiane; Popp, Max; Marotzke, Jochem

    2016-04-01

    A large fraction of recently discovered exoplanets are found in close orbit from their star. Their rotation period is expected to be slow due to important tidal forces. Therefore, in order to assess the habitability of slowly rotating planets, it is imperative to understand how slow rotation periods affect the climate. Under different Earth-like configurations, previous studies focused on the special case of synchronous rotation where the orbital and planetary rotation periods are identical. In addition, simulations with non-synchronous rotations did not account for sea ice. Therefore, we turn on the thermodynamics sea-ice model in the state-of-the-art atmospheric general circulation model ECHAM6 coupled to a mixed-layer ocean and investigate the aquaplanet's climate across rotation periods between one and 365 Earth days. Simulations with the sea-ice model turned on show a global-mean surface temperature up to 25 K lower than simulations with the sea-ice model turned off, particularly for rotation periods between 64 and 300 days. For both type of experiments, the climate cools with increasing rotation period. However, when sea ice is included, the significant drop in the global-mean surface temperature is due to sea-ice reaching low latitudes. Then, beyond a 200 days rotation period, sea ice grows over the equatorial region during the nighttime and persists well into the daytime. This causes a high contribution of the sea-ice albedo to the planetary albedo. Our study illustrates, thus, that sea-ice plays a crucial role in shaping the climate on slowly rotating planets.

  12. Self-cleaning rotating anode X-ray source

    DOEpatents

    Paulikas, Arvydas P.

    1989-01-01

    A self-cleaning rotating anode x-ray source comprising an evacuable housing, a rotatable cylindrical anode within the housing, a source of electrons within the housing which electrons are caused to impinge upon the anode to produce x-rays, and means for ionizing residual particles within the housing and accelerating such ions so as to impinge upon the anode to sputter impurities from the surface thereof.

  13. Self-cleaning rotating anode x-ray source

    DOEpatents

    Paulikas, A.P.

    1987-06-02

    A self-cleaning rotating anode x-ray source comprising and evacuable housing, a rotatable cylindrical anode within the housing, a source of electrons within the housing which electrons are caused to impinge upon the anode to produce x-rays, and means for ionizing residual particles within the housing and accelerating such ions so as to impinge upon the anode to sputter impurities from the surface thereof. 2 figs.

  14. Conceptual design of a rotating parallel-mirror-pair interferometer

    NASA Astrophysics Data System (ADS)

    Cai, Qisheng; Xiangli, Bin; Fu, Qiang; Qian, Lulu; Li, Yang; Tan, Zheng

    2014-02-01

    In the field of Fourier-transform spectroscopy, tilt and shearing problems caused by the moving components in a translational type of spectrometer reduce the quality of the interferogram dramatically. While, the spectrometer based on rotational motion can avoid these problems. In this paper, a novel rotational type of interferometer, called rotating parallel-mirror-pair interferometer (RPMPI), is presented. Its principle and properties are studied. This interferometer consists of one beam splitter, two fixed flat mirrors, and one rotating wedged parallel-mirror-pair (PMP). The optical path difference (OPD) is obtained by the rotational motion of the PMP. Factors that affect the maximum OPD include the wedged angle of the rotating PMP, the distance between the two parallel mirrors, the direction of the incident ray, and the range of rotating angle. This interferometer can operate either in swinging mode or continuous rotary mode depending on the range of the rotating angle. In swinging mode, the OPD function is linear. In continuous rotary mode, the sampling efficiency is higher and it can operate as an ultra rapid scanning interferometer.

  15. Simultaneous measurement of bacterial flagellar rotation rate and swimming speed.

    PubMed Central

    Magariyama, Y; Sugiyama, S; Muramoto, K; Kawagishi, I; Imae, Y; Kudo, S

    1995-01-01

    Swimming speeds and flagellar rotation rates of individual free-swimming Vibrio alginolyticus cells were measured simultaneously by laser dark-field microscopy at 25, 30, and 35 degrees C. A roughly linear relation between swimming speed and flagellar rotation rate was observed. The ratio of swimming speed to flagellar rotation rate was 0.113 microns, which indicated that a cell progressed by 7% of pitch of flagellar helix during one flagellar rotation. At each temperature, however, swimming speed had a tendency to saturate at high flagellar rotation rate. That is, the cell with a faster-rotating flagellum did not always swim faster. To analyze the bacterial motion, we proposed a model in which the torque characteristics of the flagellar motor were considered. The model could be analytically solved, and it qualitatively explained the experimental results. The discrepancy between the experimental and the calculated ratios of swimming speed to flagellar rotation rate was about 20%. The apparent saturation in swimming speed was considered to be caused by shorter flagella that rotated faster but produced less propelling force. Images FIGURE 1 FIGURE 4 PMID:8580359

  16. Galvano-rotational effect induced by electroweak interactions in pulsars

    SciTech Connect

    Dvornikov, Maxim

    2015-05-21

    We study electroweakly interacting particles in rotating matter. The existence of the electric current along the axis of the matter rotation is predicted in this system. This new galvano-rotational effect is caused by the parity violating interaction between massless charged particles in the rotating matter. We start with the exact solution of the Dirac equation for a fermion involved in the electroweak interaction in the rotating frame. This equation includes the noninertial effects. Then, using the obtained solution, we derive the induced electric current which turns out to flow along the rotation axis. We study the possibility of the appearance of the galvano-rotational effect in dense matter of compact astrophysical objects. The particular example of neutron and hypothetical quark stars is discussed. It is shown that, using this effect, one can expect the generation of toroidal magnetic fields comparable with poloidal ones in old millisecond pulsars. We also briefly discuss the generation of the magnetic helicity in these stars. Finally we analyze the possibility to apply the galvano-rotational effect for the description of the asymmetric neutrino emission from a neutron star to explain pulsars kicks.

  17. Galvano-rotational effect induced by electroweak interactions in pulsars

    SciTech Connect

    Dvornikov, Maxim

    2015-05-01

    We study electroweakly interacting particles in rotating matter. The existence of the electric current along the axis of the matter rotation is predicted in this system. This new galvano-rotational effect is caused by the parity violating interaction between massless charged particles in the rotating matter. We start with the exact solution of the Dirac equation for a fermion involved in the electroweak interaction in the rotating frame. This equation includes the noninertial effects. Then, using the obtained solution, we derive the induced electric current which turns out to flow along the rotation axis. We study the possibility of the appearance of the galvano-rotational effect in dense matter of compact astrophysical objects. The particular example of neutron and hypothetical quark stars is discussed. It is shown that, using this effect, one can expect the generation of toroidal magnetic fields comparable with poloidal ones in old millisecond pulsars. We also briefly discuss the generation of the magnetic helicity in these stars. Finally we analyze the possibility to apply the galvano-rotational effect for the description of the asymmetric neutrino emission from a neutron star to explain pulsars kicks.

  18. Toroidal rotation and halo current produced by disruptions

    NASA Astrophysics Data System (ADS)

    Strauss, Henry; Sugiyama, Linda; Paccagnella, Roberto; Breslau, Joshua; Jardin, Stephen

    2013-10-01

    In several experiments including JET, it was observed that disruptions were accompanied by toroidal rotation. There is a concern that there may be a resonance between rotating toroidal perturbations and the resonant frequencies of the ITER vacuum vessel, causing enhanced damage. MHD simulations with M3D demonstrate that disruptions produce toroidal rotation. The toroidal velocity can produce several rotations of the sideways force during a disruption. Edge localized modes (ELMs) also produce poloidal and toroidal rotation. A theory of rotation produced by MHD activity will be presented. In the case of ELMs, the theory gives toroidal rotation Alfven Mach number, Mϕ ~10-2βN . This is consistent with a scaling for intrinsic toroidal rotation in H mode tokamaks. It was also discovered on JET that disruptions were accompanied by toroidal variation of the plasma current Iϕ. From ∇ . j = 0 , the toroidal current variation ΔIϕ is proportional to the 3D halo current, ∮Jn Rdl , where Jn is the normal current density at the wall. The 3D halo current is calculated analytically and computationally. A bound on ΔIϕ /Iϕ is found, proportional to the halo current fraction and toroidal peaking factor. Supported by USDOE and ITER.

  19. Phytobezoar: an uncommon cause of small bowel obstruction.

    PubMed Central

    Chisholm, E. M.; Leong, H. T.; Chung, S. C.; Li, A. K.

    1992-01-01

    Phytobezoars are an unusual cause of small bowel obstruction. We report 13 patients presenting with 16 episodes of small bowel obstruction from phytobezoars. Eleven patients had previously undergone surgery for peptic ulceration (eight truncal vagotomy and pyloroplasty). A history of ingestion of persimmon fruit was common and the majority of cases presented in the autumn when this fruit is in season. One phytobezoar causing obstruction at the third part of the duodenum was removed by endoscopic fragmentation, while an episode of jejunal obstruction was precipitated by endoscopic fragmentation of a gastric bezoar. Twelve patients underwent surgery for obstruction on 15 occasions, with milking of the phytobezoar to the caecum performed in ten, enterotomy and removal in four and resection in one patient. Associated gastric phytobezoars were found in two cases and multiple small bowel bezoars in two other cases. These were removed to prevent recurrent obstruction. Phytobezoar should be considered preoperatively as a cause of obstruction in patients with previous ulcer surgery. Wherever possible milking of a phytobezoar to the caecum should be performed. Careful assessment for other phytobezoars should be made. Prevention of phytobezoars is dependent upon dietary counselling of patients by surgeons after gastric resection or vagotomy and drainage for peptic ulcer. PMID:1416706

  20. Rotation of venus: continuing contradictions.

    PubMed

    Smith, B A

    1967-10-01

    Optical observations of Venus have yielded various values of the rotation period extending from less than one to several hundred days. Radar observations give a retrograde rotation of the solid globe in 244 +/- 2 days. Recent ultraviolet photographs, however, show relatively rapid displacements of clouds in the high atmosphere of Venus which suggest a retrogrode rotation in only 5 days. The two rates seem to be physically incompatible.

  1. Rotating black droplet

    NASA Astrophysics Data System (ADS)

    Fischetti, Sebastian; Santos, Jorge E.

    2013-07-01

    We construct the gravitational dual, in the Unruh state, of the "jammed" phase of a CFT at strong coupling and infinite N on a fixed five-dimensional rotating Myers-Perry black hole with equal angular momenta. When the angular momenta are all zero, the solution corresponds to the five-dimensional generalization of the solution first studied in [1]. In the extremal limit, when the angular momenta of the Myers-Perry black hole are maximum, the Unruh, Boulware and Hartle-Hawking states degenerate. We give a detailed analysis of the corresponding holographic stress energy tensor for all values of the angular momenta, finding it to be regular at the horizon in all cases. We compare our results with existent literature on thermal states of free field theories on black hole backgrounds.

  2. Asteroid Ida Rotation Sequence

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This montage of 14 images (the time order is right to left, bottom to top) shows Ida as it appeared in the field of view of Galileo's camera on August 28, 1993. Asteroid Ida rotates once every 4 hours, 39 minutes and clockwise when viewed from above the north pole; these images cover about one Ida 'day.' This sequence has been used to create a 3-D model that shows Ida to be almost croissant shaped. The earliest view (lower right) was taken from a range of 240,000 kilometers (150,000 miles), 5.4 hours before closest approach. The asteroid Ida draws its name from mythology, in which the Greek god Zeus was raised by the nymph Ida.

  3. Stimulated rotational Raman scattering

    NASA Astrophysics Data System (ADS)

    Parazzoli, C. G.; Rafanelli, G. L.; Capps, D. M.; Drutman, C.

    1989-03-01

    The effect of Stimulated Rotational Raman Scattering (SRRS) processes on high energy laser directed energy weapon systems was studied. The program had 3 main objectives; achieving an accurate description of the physical processes involved in SRRS; developing a numerical algorithm to confidently evaluate SRRS-induced losses in the propagation of high energy laser beams in the uplink and downlink segments of the optical trains of various strategic defense system scenarios; and discovering possible methods to eliminate, or at least reduce, the deleterious effects of SRRS on the energy deposition on target. The following topics are discussed: the motivation for the accomplishments of the DOE program; the Semiclassical Theory of Non-Resonant SRRS for Diatomic Homonuclear Molecules; and then the following appendices; Calculation of the Dipole Transition Reduced Matrix Element, Guided Tour of Hughes SRRS Code, Running the Hughes SRRS Code, and Hughes SRRS Code Listing.

  4. The Rapidly Rotating Sun

    NASA Technical Reports Server (NTRS)

    Hanasoge, Shravan M.; Duvall, Thomas L., Jr.; Sreenivasan, Katepalli R.

    2012-01-01

    Convection in the solar interior is thought to comprise structures at a continuum of scales, from large to small. This conclusion emerges from phenomenological studies and numerical simulations though neither covers the proper range of dynamical parameters of solar convection. In the present work, imaging techniques of time-distance helioseismology applied to observational data reveal no long-range order in the convective motion. We conservatively bound the associated velocity magnitudes, as a function of depth and the spherical-harmonic degree l to be 20-100 times weaker than prevailing estimates within the wavenumber band l < 60. The observationally constrained kinetic energy is approximately a thousandth of the theoretical prediction, suggesting the prevalence of an intrinsically different paradigm of turbulence. A fundamental question arises: what mechanism of turbulence transports the heat ux of a solar luminosity outwards? The Sun is seemingly a much faster rotator than previously thought, with advection dominated by Coriolis forces at scales l < 60.

  5. Plasma rotation induced by RF

    SciTech Connect

    Chan, V. S.; Chiu, S. C.; Lin-Liu, Y. R. [General Atomics, P.O. Box 85608, San Diego, California 92186-5698; Omelchenko, Y. A. [General Atomics, P.O. Box 85608, San Diego, California 92186-5698

    1999-09-20

    Plasma rotation has many beneficial effects on tokamak operation including stabilization of MHD and microturbulence to improve the beta limit and confinement. Contrary to present-day tokamaks, neutral beams may not be effective in driving rotation in fusion reactors; hence the investigation of radiofrequency (RF) induced plasma rotation is of great interest and potential importance. This paper reviews the experimental results of RF induced rotation and possible physical mechanisms, suggested by theories, to explain the observations. This subject is only in the infancy of its research and many challenging issues remained to be understood and resolved. (c) 1999 American Institute of Physics.

  6. Electronic Control Of Slow Rotations

    NASA Technical Reports Server (NTRS)

    Howard, David E.; Smith, Dennis A.

    1992-01-01

    Digital/analog circuit controls both angular position and speed of rotation of motor shaft with high precision. Locks angular position of motor to phase of rotation-command clock signal at binary submultiple of master clock signal. Circuit or modified version used to control precisely position and velocity of robotic manipulator, to control translation mechanism of crystal-growing furnace, to position hands of mechanical clock, or to control angular position and rate of rotation in any of large variety of rotating mechanisms.

  7. Rotation and particle loss in Tore Supra

    SciTech Connect

    R.B. White; F.W. Perkins; X. Garbet; C. Bourdelle; et al

    2000-06-13

    Although plasma heating with ICRF imparts negligible angular momentum to a tokamak plasma, the high energy particles give significant torque to the plasma through diamagnetic effects. This effect has been directly modeled through guiding center simulations. It is found that heating in Tore Supra, with the location of the resonance surface on the high field side of the magnetic axis, can produce negative central rotation of up to 40 km/sec. Particle loss also contributes to negative rotation, but this is not the dominant effect in most discharges. In this work the authors examine the effect of collisions and strong plasma rotation on the loss of high energy particles. Magnetic field strength variation due to discrete toroidal field coils, or ripple, produces two important loss channels in tokamaks. The trapping of particles in local ripple wells produces super banana orbits and, in the case of strong ripple, direct loss orbits leading to the plasma edge. These particles leave the device in the direction of vertical drift, and are characterized by small values of parallel velocity, or pitch. Ripple also causes high energy particles in banana orbits to diffuse stochastically, leading to banana orbits which impact the wall near the outer midplane. Both these loss processes are modified by the magnitude of the collision rate, and by plasma rotation. In Tore Supra the magnitude of the ripple makes ripple trapping a dominant loss mechanism for the background plasma as well as for ICRF produced non Maxwellian high energy tails. The authors have examined the loss as a function of collisionality and rotation using the Hamiltonian guiding center code ORBIT.

  8. Image Rotation Does Not Rotate Smooth Eye Movements

    NASA Technical Reports Server (NTRS)

    Mulligan, Jeffrey B.; Stone, Leland S. (Technical Monitor)

    1997-01-01

    Subjects viewing a drifting noise pattern make reflexive smooth eye movements in the direction of motion, which follow rapid changes in movement direction. These responses are unaffected by rotations of the pattern, suggesting that there is no coupling between visually sensed rotation and the direction of ocular following.

  9. Modeling rigid magnetically rotated microswimmers: Rotation axes, bistability, and controllability

    NASA Astrophysics Data System (ADS)

    Meshkati, Farshad; Fu, Henry Chien

    2014-12-01

    Magnetically actuated microswimmers have recently attracted attention due to many possible biomedical applications. In this study we investigate the dynamics of rigid magnetically rotated microswimmers with permanent magnetic dipoles. Our approach uses a boundary element method to calculate a mobility matrix, accurate for arbitrary geometries, which is then used to identify the steady periodically rotating orbits in a co-rotating body-fixed frame. We evaluate the stability of each of these orbits. We map the magnetoviscous behavior as a function of dimensionless Mason number and as a function of the angle that the magnetic field makes with its rotation axis. We describe the wobbling motion of these swimmers by investigating how the rotation axis changes as a function of experimental parameters. We show that for a given magnetic field strength and rotation frequency, swimmers can have more than one stable periodic orbit with different rotation axes. Finally, we demonstrate that one can improve the controllability of these types of microswimmers by adjusting the relative angle between the magnetic field and its axis of rotation.

  10. Unidirectional rotating coordinate rotation digital computer algorithm based on rotational phase estimation.

    PubMed

    Zhang, Chaozhu; Han, Jinan; Yan, Huizhi

    2015-06-01

    The improved coordinate rotation digital computer (CORDIC) algorithm gives high precision and resolution phase rotation, but it has some shortages such as high iterations and big system delay. This paper puts forward unidirectional rotating CORDIC algorithm to solve these problems. First, using under-damping theory, a part of unidirectional phase rotations is carried out. Then, the threshold value of angle is determined based on phase rotation estimation method. Finally, rotation phase estimation completes the rest angle iterations. Furthermore, the paper simulates and implements the numerical control oscillator by Quartus II software and Modelsim software. According to the experimental results, the algorithm reduces iterations and judgment of sign bit, so that it decreases system delay and resource utilization and improves the throughput. We always analyze the error brought by this algorithm. It turned out that the algorithm has a good application prospect in global navigation satellite system and channelized receiver. PMID:26133856

  11. Rotational period of GQ Lupi

    NASA Astrophysics Data System (ADS)

    Broeg, C.; Schmidt, T. O. B.; Guenther, E.; Gaedke, A.; Bedalov, A.; Neuhäuser, R.; Walter, F. M.

    2007-06-01

    Aims: We wanted to determine the rotation parameters of GQ Lup A, thereby constraining the evolutionary history of the GQ Lup system. Methods: We have undertaken a photometric monitoring campaign on GQ Lup A consisting of two epochs spaced one year apart. We also searched the photometric archives to enlarge the data set. Results: We were able to determine the photometric period (8.45±0.2 days) in both epochs in several photometric bands. This periodicity could also be found in some of the archival data. The combined false-alarm probability is 0.015. The variation is most likely caused by hot spots on the surface of GQ Lup A. This, combined with high-resolution spectra (v sin i) allows calculation of GQ Lup A's inclination (i=27±5°). Radial velocity data also contains this period but is inconclusive. Nevertheless, the RV data supports the interpretation that hot spots cause the photometric variation. We use the known K-band variability, amplitude, and phase of GQ Lup A together with a new image of GQ Lup A+b, taken quasi-simultaneously with our monitoring of the star, to confirm the magnitude and, hence, luminosity of the companion. Based on observations obtained on Cerro Paranal, Chile, in ESO program 075.C-0710(C) and on La Silla, Chile, in ESO programs 074.C-0034(A),075.C-0710(E), 075.C-0710(F), 075.C-0202(A), 076.C-0010(A) as well as with ANDICAM of the SMARTS consortium. Photometry data of epochs I and II are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/468/1039

  12. The deconjugation ability of bacteria isolated from the jejunal fluids in the blind loop syndrome with high sup 14 CO sub 2 excretion. Using the breath analysis technique and thin-layer chromatography

    SciTech Connect

    Shindo, K.; Yamazaki, R.; Mizuno, T.; Shionoiri, H.; Sugiyama, M. )

    1989-01-01

    Five patients with blind loop syndrome (Billroth II) were examined by measuring {sup 14}CO{sub 2} specific activity of expired breath samples taken at intervals after a meal containing glycine-1-{sup 14}C cholate. The 5 patients tested showed a marked increase of {sup 14}CO{sub 2} specific activity. Furthermore, the ability of deconjugation of bacteria isolated from the jejunal fluids in the efferent loop of these patients was tested by thin-layer chromatography. The bacterial species identified from the samples were as follows: enterococcus, Lactobacillus buchneri, L. bifidus, L. brevis, Eubacterium lentum, Bacteroides vulgaricus, B. filamentosum, Corynebacterium granulosum, Escherichia coli, Staphylococcus epidermidis, and Aerobacter aerogenes. These species of bacteria, except E. coli and A. aerogenes, showed the deconjugation ability by which conjugated bile acids in ox gall was hydrolyzed. Administration of chloramphenicol to the 5 patients reduced {sup 14}CO{sub 2} specific activity significantly. On the other hand, 9 healthy men who were tested showed a flat curve, and 8 of the 9 had no growth of bacteria isolated from the jejunal fluids. The remaining healthy man showed an over growth of E. coli and Pseudomonas aeruginosa, but the species did not have the ability of deconjugation.

  13. Surface dimpling on rotating work piece using rotation cutting tool

    DOEpatents

    Bhapkar, Rohit Arun; Larsen, Eric Richard

    2015-03-31

    A combined method of machining and applying a surface texture to a work piece and a tool assembly that is capable of machining and applying a surface texture to a work piece are disclosed. The disclosed method includes machining portions of an outer or inner surface of a work piece. The method also includes rotating the work piece in front of a rotating cutting tool and engaging the outer surface of the work piece with the rotating cutting tool to cut dimples in the outer surface of the work piece. The disclosed tool assembly includes a rotating cutting tool coupled to an end of a rotational machining device, such as a lathe. The same tool assembly can be used to both machine the work piece and apply a surface texture to the work piece without unloading the work piece from the tool assembly.

  14. Role of G-proteins in muscarinic receptor inward and outward currents in rabbit jejunal smooth muscle.

    PubMed Central

    Komori, S; Bolton, T B

    1990-01-01

    1. Single smooth muscle cells obtained by enzymic dispersion of the longitudinal muscle layer of rabbit jejunum were held under voltage clamp using patch pipettes and membrane currents measured. The effects of carbachol or caffeine applied externally were examined in cells dialysed with normal pipette solutions or with a solution containing heparin (which blocks receptors for D-myo-inositol 1,4,5-trisphosphate, InsP3), guanosine 5-O-(gamma-thio)triphosphate (GTP gamma S) or guanosine 5-O-(beta-thio)diphosphate (GDP beta S). 2. Outward current in response to application of carbachol or caffeine was considered to represent the opening of calcium-activated potassium channels in response to a localized rise in the free ionized calcium concentration occasioned by the rapid discharge of stored calcium (Ca) by these agents. 3. Heparin included in the pipette solution blocked outward current to muscarinic receptor activation by carbachol but not that to caffeine, suggesting that receptor-evoked discharge of stored cellular Ca is caused by InsP3 action. However, heparin did not affect muscarinic-receptor inward current. 4. After dialysis with 0.1-0.5 mM-GTP gamma S, carbachol inward current was evoked in two out of three of the cells; after dialysis with 0.1-0.2 mM-GTP gamma S for an average of 7.7 min it was 80% of the normal response; after dialysis for an average of 8.6 min with 0.5 mM-GTP gamma S it was 31% of the normal response. In contrast, 0.1 mM-GTP gamma S reduced caffeine outward current by 93% after an average 4.5 min dialysis and spontaneous transient outward currents (STOCs) were abolished in 2.9 min on average. 5. Carbachol inward current (at -40 or -50 mV) and carbachol outward current (at 0 mV) in responding cells were reduced only by half after 8-10 min dialysis with 1 mM-GDP beta S which has been shown in portal vein cells to antagonize the depletion of Ca stores by intracellular GTP gamma S (Komori & Bolton, 1989). After 8-10 min dialysis with 5 m

  15. SOLiD SAGE sequencing shows differential gene expression in jejunal lymph node samples of resistant and susceptible red deer (Cervus elaphus) challenged with Mycobacterium avium subsp. paratuberculosis.

    PubMed

    Mackintosh, C G; Griffin, J F T; Scott, I C; O'Brien, R; Stanton, J L; MacLean, P; Brauning, R

    2016-01-01

    and higher MAP numbers in lymph nodes of S animals. By week 50 the number of upregulated genes declined in both groups. A number of genes upregulated in R animals appear to be associated with host resistance and regulation of adaptive immunity, especially CEACAM8. Genes upregulated in S animals involve antigen presentation (ENDOD1) and gut associated immune pathology (HSH2D). In conclusion, gene expression in jejunal lymph nodes of resistant and susceptible deer infer that the resistant phenotype is associated with pathways of adaptive immunity, while susceptibility is linked with upregulated non-protective pro-inflammatory responses, following experimental MAP infection. PMID:26620077

  16. Quartic Rotation Criteria and Algorithms.

    ERIC Educational Resources Information Center

    Clarkson, Douglas B.; Jennrich, Robert I.

    1988-01-01

    Most of the current analytic rotation criteria for simple structure in factor analysis are summarized and identified as members of a general symmetric family of quartic criteria. A unified development of algorithms for orthogonal and direct oblique rotation using arbitrary criteria from this family is presented. (Author/TJH)

  17. KEPLER RAPIDLY ROTATING GIANT STARS

    SciTech Connect

    Costa, A. D.; Martins, B. L. Canto; Bravo, J. P.; Paz-Chinchón, F.; Chagas, M. L. das; Leão, I. C.; Oliveira, G. Pereira de; Silva, R. Rodrigues da; Roque, S.; Oliveira, L. L. A. de; Silva, D. Freire da; De Medeiros, J. R.

    2015-07-10

    Rapidly rotating giant stars are relatively rare and may represent important stages of stellar evolution, resulting from stellar coalescence of close binary systems or accretion of substellar companions by their hosting stars. In the present Letter, we report 17 giant stars observed in the scope of the Kepler space mission exhibiting rapid rotation behavior. For the first time, the abnormal rotational behavior for this puzzling family of stars is revealed by direct measurements of rotation, namely from photometric rotation period, exhibiting a very short rotation period with values ranging from 13 to 55 days. This finding points to remarkable surface rotation rates, up to 18 times the rotation of the Sun. These giants are combined with six others recently listed in the literature for mid-infrared (IR) diagnostics based on Wide-field Infrared Survey Explorer information, from which a trend for an IR excess is revealed for at least one-half of the stars, but at a level far lower than the dust excess emission shown by planet-bearing main-sequence stars.

  18. Spatially homogeneous rotating world models.

    NASA Technical Reports Server (NTRS)

    Ozsvath, I.

    1971-01-01

    The mathematical problem encountered when looking for the simplest expanding and rotating model of the universe without the compactness condition for the space sections is formulated. The Lagrangian function is derived for four different rotating universes simultaneously. These models correspond in a certain sense to Godel's (1950) ?symmetric case.'

  19. Optomechanics for absolute rotation detection

    NASA Astrophysics Data System (ADS)

    Davuluri, Sankar

    2016-07-01

    In this article, we present an application of optomechanical cavity for the absolute rotation detection. The optomechanical cavity is arranged in a Michelson interferometer in such a way that the classical centrifugal force due to rotation changes the length of the optomechanical cavity. The change in the cavity length induces a shift in the frequency of the cavity mode. The phase shift corresponding to the frequency shift in the cavity mode is measured at the interferometer output to estimate the angular velocity of absolute rotation. We derived an analytic expression to estimate the minimum detectable rotation rate in our scheme for a given optomechanical cavity. Temperature dependence of the rotation detection sensitivity is studied.

  20. Acoustic controlled rotation and orientation

    NASA Technical Reports Server (NTRS)

    Barmatz, Martin B. (Inventor); Allen, James L. (Inventor)

    1989-01-01

    Acoustic energy is applied to a pair of locations spaced about a chamber, to control rotation of an object levitated in the chamber. Two acoustic transducers applying energy of a single acoustic mode, one at each location, can (one or both) serve to levitate the object in three dimensions as well as control its rotation. Slow rotation is achieved by initially establishing a large phase difference and/or pressure ratio of the acoustic waves, which is sufficient to turn the object by more than 45 deg, which is immediately followed by reducing the phase difference and/or pressure ratio to maintain slow rotation. A small phase difference and/or pressure ratio enables control of the angular orientation of the object without rotating it. The sphericity of an object can be measured by its response to the acoustic energy.

  1. Factors affecting rotator cuff healing.

    PubMed

    Mall, Nathan A; Tanaka, Miho J; Choi, Luke S; Paletta, George A

    2014-05-01

    Several studies have noted that increasing age is a significant factor for diminished rotator cuff healing, while biomechanical studies have suggested the reason for this may be an inferior healing environment in older patients. Larger tears and fatty infiltration or atrophy negatively affect rotator cuff healing. Arthroscopic rotator cuff repair, double-row repairs, performing a concomitant acromioplasty, and the use of platelet-rich plasma (PRP) do not demonstrate an improvement in structural healing over mini-open rotator cuff repairs, single-row repairs, not performing an acromioplasty, or not using PRP. There is conflicting evidence to support postoperative rehabilitation protocols using early motion over immobilization following rotator cuff repair. PMID:24806015

  2. Rotating Stars Can Help Planets Become Habitable

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2015-12-01

    What characteristics must a terrestrial planet exhibit to have the potential to host life? Orbiting within the habitable zone of its host star is certainly a good start, but theres another important aspect: the planet has to have the right atmosphere. A recent study has determined how host stars can help their planets to lose initial, enormous gaseous envelopes and become more Earth-like.Collecting An EnvelopeWhen a terrestrial planet forms inside a gaseous protoplanetary disk, it can accumulate a significant envelope of hydrogen gas causing the planet to bear more similarity to a mini-Neptune than to Earth. Before the planet can become habitable, it must shed this enormous, primordial hydrogen envelope, so that an appropriate secondary atmosphere can form.So what determines whether a planet can get rid of its protoatmosphere? The dominant process for shedding a hydrogen atmosphere is thermal mass loss: as the planets upper atmosphere is heated by X-ray and extreme-ultraviolet (XUV) radiation from the host star, the envelope evaporates.A Critical DependenceIn a recent study led by Colin Johnstone (University of Vienna), a team of scientists has developed models of this evaporation process for hydrogen planetary atmospheres. In particular, Johnstone and collaborators examine how the host stars initial rotation rate which strongly impacts the stars level of XUV activity affects the degree to which the planets hydrogen atmosphere is evaporated, and the rate at which the evaporation occurs.The authors findings can be illustrated with the example of an Earth-mass planet located in the habitable zone of a solar-mass star. In this case, the authors find four interesting regimes (shown in the plot to the right):Evolution of the hydrogen protoatmosphere of an Earth-mass planet in the habitable zone of a solar-mass star. The four lettered cases describe different initial atmospheric masses. The three curves for each case describe the stellar rotation rate: slow (red

  3. Rotating Bondi Accretion Flow

    NASA Astrophysics Data System (ADS)

    Park, Myeong-Gu; Han, Du-Hwan

    2016-06-01

    The characteristics of accretion flow onto a black hole are determined by the physical condition of gas at large radius. When the gas has no angular momentum and is polytropic, the accretion flow becomes the classic Bondi flow. The mass accretion rate in such case is an eigenvalue and uniquely determined by the density and the temperature of the surrounding gas for a given black hole mass. When the gas has angular momentum above some critical value, the angular momentum of the gas should be removed by viscosity to reach the black hole horizon. We study, within the slim disk approximation, rotating polytropic accretion flow with alpha viscosity as an an extension of the Bondi flow. The characteristics of the accretion flow are now determined by the temperature, density, and angular momentum of the gas at the outer boundary. We explore the effects of the viscosity parameter and the outer boundary radius on the physical characteristic of the flow, especially on the mass accretion rate, and compare the result with previous works of Park (2009) and Narayan & Fabian (2011).

  4. Simulating rotational grazing management.

    PubMed

    Cros, M J; Duru, M; Garcia, F; Martin-Clouaire, R

    2001-09-01

    Dairy systems predominantly based on rotational grazing are notoriously hard to manage. In order to ensure profitability, this type of production requires quite good organisation, planning, and operating capability on the part of the farmer. A simulation-based decision support system, called SEPATOU, has been developed for this purpose. At the core of the decision support approach lies an explicit and rigorous modelling of the management strategy that underlies a dairy farmer's decision-making behaviour (real or hypothetical). The SEPATOU system is a discrete-event simulator that reproduces the day-to-day dynamics of the farmer's decision process and the response of the controlled biophysical system for which models of grass growth, animal consumption, and milk production are used. SEPATOU provides the means to evaluate and compare tentative strategies by simulating their application throughout the production season under different hypothetical weather conditions. The relative worth of a strategy can be assessed by analysing the effects on the biophysical system and their variability across the representative range of possible conditions that is considered. The activities to be managed concern the type and amount of conserved feed, where to fertilise and how much, the choice of fields to harvest, and most importantly, which field to graze next. Typically, SEPATOU is designed to be used by extension services and farming system scientists. It is implemented in C++ and is currently undergoing a validation process with the intended users. PMID:11697661

  5. Generalized investigation of the rotation-activity relation: favoring rotation period instead of Rossby number

    SciTech Connect

    Reiners, A.; Passegger, V. M.; Schüssler, M.

    2014-10-20

    Magnetic activity in Sun-like and low-mass stars causes X-ray coronal emission which is stronger for more rapidly rotating stars. This relation is often interpreted in terms of the Rossby number, i.e., the ratio of rotation period to convective overturn time. We reconsider this interpretation on the basis of the observed X-ray emission and rotation periods of 821 stars with masses below 1.4 M {sub ☉}. A generalized analysis of the relation between X-ray luminosity normalized by bolometric luminosity, L {sub X}/L {sub bol}, and combinations of rotational period, P, and stellar radius, R, shows that the Rossby formulation does not provide the solution with minimal scatter. Instead, we find that the relation L {sub X}/L {sub bol}∝P {sup –2} R {sup –4} optimally describes the non-saturated fraction of the stars. This relation is equivalent to L {sub X}∝P {sup –2}, indicating that the rotation period alone determines the total X-ray emission. Since L {sub X} is directly related to the magnetic flux at the stellar surface, this means that the surface flux is determined solely by the star's rotation and is independent of other stellar parameters. While a formulation in terms of a Rossby number would be consistent with these results if the convective overturn time scales exactly as L{sub bol}{sup −1/2}, our generalized approach emphasizes the need to test a broader range of mechanisms for dynamo action in cool stars.

  6. Bone anatomy and rotational alignment in total knee arthroplasty.

    PubMed

    Uehara, K; Kadoya, Y; Kobayashi, A; Ohashi, H; Yamano, Y

    2002-09-01

    The purpose of the current study was to investigate the bone anatomy in determining the rotational alignment in total knee arthroplasty using computed tomography. Axial images of 109 knees in 83 patients with varus osteoarthritis who had total knee arthroplasty were analyzed. On the images of the distal femur and the proximal tibia, a baseline for the anteroposterior axis of each component was drawn based on the epicondylar axis for the femur and the medial (1/3) of the tibial tuberosity for the tibia. The angle between these two lines was analyzed as the rotational mismatch between the components when they were aligned to the anatomic landmarks of each bone. Fifty-four knees (49.5%) had an angle of 5 degrees or greater and 13 knees (11.9%) had an angle of 10 degrees or greater. There was a tendency to align the tibial component in external rotation relative to the femoral component. The results indicated that the landmarks of each bone were the intrinsic cause of the rotational mismatch in knees with varus osteoarthritis. Surgeons doing total knee arthroplasties should be aware of this and check the rotational mismatch between the components. When it is present, the tibial component should be realigned to match the femoral component rotation to minimize problems caused by the mismatch.

  7. Improved apparatus for predictive diagnosis of rotator cuff disease

    NASA Astrophysics Data System (ADS)

    Pillai, Anup; Hall, Brittany N.; Thigpen, Charles A.; Kwartowitz, David M.

    2014-03-01

    Rotator cuff disease impacts over 50% of the population over 60, with reports of incidence being as high as 90% within this population, causing pain and possible loss of function. The rotator cuff is composed of muscles and tendons that work in tandem to support the shoulder. Heavy use of these muscles can lead to rotator cuff tear, with the most common causes is age-related degeneration or sport injuries, both being a function of overuse. Tears ranges in severity from partial thickness tear to total rupture. Diagnostic techniques are based on physical assessment, detailed patient history, and medical imaging; primarily X-ray, MRI and ultrasonography are the chosen modalities for assessment. The final treatment technique and imaging modality; however, is chosen by the clinician is at their discretion. Ultrasound has been shown to have good accuracy for identification and measurement of full-thickness and partial-thickness rotator cuff tears. In this study, we report on the progress and improvement of our method of transduction and analysis of in situ measurement of rotator cuff biomechanics. We have improved the ability of the clinician to apply a uniform force to the underlying musculotendentious tissues while simultaneously obtaining the ultrasound image. This measurement protocol combined with region of interest (ROI) based image processing will help in developing a predictive diagnostic model for treatment of rotator cuff disease and help the clinicians choose the best treatment technique.

  8. Glenohumeral internal rotation deficit: pathogenesis and response to acute throwing.

    PubMed

    Kibler, W Ben; Sciascia, Aaron; Thomas, Stephen J

    2012-03-01

    Overhand throwing places high loads and stresses on the joints and tissues of the shoulder and arm. As a result, throwing athletes regularly demonstrate altered shoulder internal and external ranges of motion where internal rotation (IR) is decreased and external rotation is increased in the dominant arm when compared with the nondominant arm. This alteration can exist as a result of alterations to the bones (humeral retroversion), capsule (posterior thickening), or muscle (passive stiffness known as thixotropy). When the amount of IR or total arc of motion difference reaches a certain threshold (typically 20 or more degrees of IR or 8 degrees total arc difference), it is known as glenohumeral internal rotation deficit or total arc of motion deficit. Glenohumeral internal rotation deficit and total arc of motion deficit can cause alterations in biomechanics such as scapular "wind-up" or alteration of glenohumeral joint kinematics, which can in turn lead to clinical findings of impingement and labral pathology. This study will review the causes of motion alteration, effects of altered motion on the throwing motion, provide definitions for the various types of rotation deficits, and how to evaluate and treat rotational deficits.

  9. Rotational polarities of sudden impulses in the magnetotail lobe

    NASA Technical Reports Server (NTRS)

    Kawano, H.; Yamamoto, T.; Kokubun, S.; Lepping, R. P.

    1992-01-01

    A sudden impulse (SI) is a sudden change in the magnetic field strength which is caused by a change in the solar wind pressure and is observed throughout the magnetosphere. In this report we have examined the rotations of the magnetic field vectors at times of SIs in the magnetotail lobe, by using IMP 6, 7, and 8 magnetometer data. The following properties have been found: (1) at the time of SI the arrowhead of the magnetic vector tends to rotate in one plane; (2) the plane of rotation tends to include the unperturbed magnetic field vector; (3) the plane of rotation tends to be aligned with the radial direction from the magnetotail axis; and (4) the magnetic vectors have a particular rotational polarity: when the plane of rotation is viewed so that the Sun is to the right of the viewed plane and the magnetotail axis is to the bottom, the arrowhead of the vector tends to rotate counterclockwise in this plane. These magnetic vector properties are consistent with those expected when part of an increase in solar wind lateral pressure squeezes the magnetotail axisymmetrically while moving tailward.

  10. General-relativistic rotation laws in rotating fluid bodies

    NASA Astrophysics Data System (ADS)

    Mach, Patryk; Malec, Edward

    2015-06-01

    We formulate new general-relativistic extensions of Newtonian rotation laws for self-gravitating stationary fluids. They have been used to rederive, in the first post-Newtonian approximation, the well-known geometric dragging of frames. We derive two other general-relativistic weak-field effects within rotating tori: the recently discovered dynamic antidragging and a new effect that measures the deviation from the Keplerian motion and/or the contribution of the fluids self-gravity. One can use the rotation laws to study the uniqueness and the convergence of the post-Newtonian approximations as well as the existence of the post-Newtonian limits.

  11. The influence of clinostat rotation on the fertilized amphibian egg.

    NASA Technical Reports Server (NTRS)

    Tremor, J. W.; Souza, K. A.

    1972-01-01

    Study in which unrestrained, fertilized eggs of Rana pipiens and Xenopus laevis were rotated in a plane parallel to the normal gravity vector. In R. pipiens rotation at 1/4 rpm for five days at 18 C produced a significantly increased number of commonly occurring abnormalities. Rotation at 1/15, 1/8, 1, 2, 5 and 10 rpm did not significantly affect normal development. X. laevis eggs reacted similarly. R. pipiens eggs were most sensitive to rotation at 1/4 rpm when exposure was initiated before first cleavage. Mixing of intracellular constituents apparently occurred only at 1/4 rpm in R. pipiens (of the clinostat speeds studied), and may have been the cause of the increased abnormality observed at this rate.

  12. The Rotational Excitation Temperature of the 6614 DIB Carrier

    NASA Technical Reports Server (NTRS)

    Cami, J.; Salama, F.; Jimenez-Vicente, J.; Galazutdinov, G.; Krelowski, J.

    2004-01-01

    Analysis of high spectral resolution observations of the lambda6614 DIB line profile show systematic variations in the positions of the peaks in the substructure of the profile. These variations can only be understood in the framework of rotational contours of large molecules, where the variations are caused by changes in the rotational excitation temperature. We show that the rotational excitation temperature for the DIB carrier is of the order 10-40 K - much lower than the gas kinetic temperature - indicating that for this particular DIB carrier angular momentum buildup is not very efficient. The rotational constant indicates that the carrier of this DIB is smaller than previously assumed:7-22 C atoms, depending on the geometry.

  13. Electric-field-induced rotation of Brownian metal nanowires.

    PubMed

    Arcenegui, Juan J; García-Sánchez, Pablo; Morgan, Hywel; Ramos, Antonio

    2013-09-01

    We describe the physical mechanism responsible for the rotation of Brownian metal nanowires suspended in an electrolyte exposed to a rotating electric field. The electric field interacts with the induced charge in the electrical double layer at the metal-electrolyte interface, causing rotation due to the torque on the induced dipole and to the induced-charge electro-osmotic flow around the particle. Experiments demonstrate that the primary driving mechanism is the former of these two. Our analysis contrasts with previous work describing the electrical manipulation of metallic particles with electric fields, which neglected the electrical double layer. Theoretical values for the rotation speed are calculated and good agreement with experiments is found.

  14. Rotational bursting of interplanetary dust particles

    NASA Technical Reports Server (NTRS)

    Paddack, S. J.; Rhee, J. W.

    1974-01-01

    Solar radiation pressure is discussed as a cause of rotational bursting, and of eventual elimination of asymmetric dust particles from the solar system, by a windmill effect. The predicted life span with this process for metallic particles with radii of 0.00001 to 0.01 cm ranges from 10 to 10,000 years. The effects of magnetic spin damping were considered. This depletion mechanism works faster than the traditional Poynting-Robertson effect by approximately one order of magnitude for metallic particles and about two orders of magnitude for nonmetallic particles.

  15. Rotational bursting of interplanetary dust particles

    NASA Technical Reports Server (NTRS)

    Paddack, S. J.; Rhee, J. W.

    1975-01-01

    Solar radiation pressure can cause rotational bursting and eventual elimination from the solar system of asymmetric dust particles by a windmill effect. The life span against this process for metallic particles with radii of 0.00001-0.01 cm ranges from 10 to 10,000 years. The effects of magnetic spin damping have been considered in this estimate. This depletion mechanism works faster than the traditional Poynting-Robertson effect by approximately one order of magnitude for metallic particles and about two-orders of magnitude for nonmetallic particles.

  16. Compact, Precise Inertial Rotation Sensors for Spacecraft

    NASA Technical Reports Server (NTRS)

    Rosing, David; Oseas, Jeffrey; Korechoff, Robert

    2006-01-01

    A document describes a concept for an inertial sensor for measuring the rotation of an inertially stable spacecraft around its center of gravity to within 100 microarcseconds or possibly even higher precision. Whereas a current proposal for a spacecraft-rotation sensor of this accuracy requires one spacecraft dimension on the order of ten meters, a sensor according to this proposal could fit within a package smaller than 1 meter and would have less than a tenth of the mass. According to the concept, an inertial mass and an apparatus for monitoring the mass would be placed at some known distance from the center of gravity so that any rotation of the spacecraft would cause relative motion between the mass and the spacecraft. The relative motion would be measured and, once the displacement of the mass exceeded a prescribed range, a precisely monitored restoring force would be applied to return the mass to a predetermined position. Measurements of the relative motion and restoring force would provide information on changes in the attitude of the spacecraft. A history of relative motion and restoring-force measurements could be kept, enabling determination of the cumulative change in attitude during the observation time.

  17. Flare differentially rotates sunspot on Sun's surface

    NASA Astrophysics Data System (ADS)

    Liu, Chang; Xu, Yan; Cao, Wenda; Deng, Na; Lee, Jeongwoo; Hudson, Hugh S.; Gary, Dale E.; Wang, Jiasheng; Jing, Ju; Wang, Haimin

    2016-10-01

    Sunspots are concentrations of magnetic field visible on the solar surface (photosphere). It was considered implausible that solar flares, as resulted from magnetic reconnection in the tenuous corona, would cause a direct perturbation of the dense photosphere involving bulk motion. Here we report the sudden flare-induced rotation of a sunspot using the unprecedented spatiotemporal resolution of the 1.6 m New Solar Telescope, supplemented by magnetic data from the Solar Dynamics Observatory. It is clearly observed that the rotation is non-uniform over the sunspot: as the flare ribbon sweeps across, its different portions accelerate (up to ~50° h-1) at different times corresponding to peaks of flare hard X-ray emission. The rotation may be driven by the surface Lorentz-force change due to the back reaction of coronal magnetic restructuring and is accompanied by a downward Poynting flux. These results have direct consequences for our understanding of energy and momentum transportation in the flare-related phenomena.

  18. Flare differentially rotates sunspot on Sun's surface

    PubMed Central

    Liu, Chang; Xu, Yan; Cao, Wenda; Deng, Na; Lee, Jeongwoo; Hudson, Hugh S.; Gary, Dale E.; Wang, Jiasheng; Jing, Ju; Wang, Haimin

    2016-01-01

    Sunspots are concentrations of magnetic field visible on the solar surface (photosphere). It was considered implausible that solar flares, as resulted from magnetic reconnection in the tenuous corona, would cause a direct perturbation of the dense photosphere involving bulk motion. Here we report the sudden flare-induced rotation of a sunspot using the unprecedented spatiotemporal resolution of the 1.6 m New Solar Telescope, supplemented by magnetic data from the Solar Dynamics Observatory. It is clearly observed that the rotation is non-uniform over the sunspot: as the flare ribbon sweeps across, its different portions accelerate (up to ∼50° h−1) at different times corresponding to peaks of flare hard X-ray emission. The rotation may be driven by the surface Lorentz-force change due to the back reaction of coronal magnetic restructuring and is accompanied by a downward Poynting flux. These results have direct consequences for our understanding of energy and momentum transportation in the flare-related phenomena. PMID:27721463

  19. Rotation induced mixing in stellar interiors

    NASA Astrophysics Data System (ADS)

    Zahn, J.-P.

    2013-12-01

    The standard model of stellar structure is unable to account for various observational facts, such as anomalies in the surface composition, and there is now a broad consensus that some extra mixing must occur in the radiation zones, in addition to the always present convective overshoot or penetration. The search for the causes of this extra mixing started in the late seventies, and it was quickly realized - in particular by Sylvie Vauclair and her co-workers - that some mild turbulence must be present to counteract the effect of gravitational settling and radiative levitation. What could be responsible for this turbulence? One suggestion was the internal gravity waves emitted at the boundary of convection zones, but it is still not established whether these waves will lead to true mixing. However they transport angular momentum, and therefore they generate differential rotation, which may be shear-unstable and thus lead to turbulence. Another way to transport angular momentum and produce an unstable rotation profile is through the large-scale circulation which is induced by the structural adjustments as the star evolves, or by the torques applied to it (due to stellar wind, accretion, tides). These processes participate in what is called the "rotational mixing"; their implementation in stellar evolution codes - again under Sylvie's impulse - has given birth to a new generation of stellar models, which agree much better with the observational constraints, although there is still room for improvement.

  20. Slowly rotating thin shell gravastars

    NASA Astrophysics Data System (ADS)

    Uchikata, Nami; Yoshida, Shijun

    2016-01-01

    We construct the solutions of slowly rotating gravastars with a thin shell. In the zero-rotation limit, we consider the gravastar composed of a de Sitter core, a thin shell, and Schwarzschild exterior spacetime. The rotational effects are treated as small axisymmetric and stationary perturbations. The perturbed internal and external spacetimes are matched with a uniformly rotating thin shell. We assume that the angular velocity of the thin shell, Ω, is much smaller than the Keplerian frequency of the nonrotating gravastar, {{{Ω }}}{{k}}. The solutions within an accuracy up to the second order of {{Ω }}/{{{Ω }}}{{k}} are obtained. The thin shell matter is assumed to be described by a perfect fluid and to satisfy the dominant energy condition in the zero-rotation limit. In this study, we assume that the equation of state for perturbations is the same as that of the unperturbed solution. The spherically symmetric component of the energy density perturbations, δ {σ }0, is assumed to vanish independently of the rotation rate. Based on these assumptions, we obtain many numerical solutions and investigate properties of the rotational corrections to the structure of the thin shell gravastar.

  1. Gravity darkening in rotating stars

    NASA Astrophysics Data System (ADS)

    Espinosa Lara, F.; Rieutord, M.

    2011-09-01

    Context. Interpretation of interferometric observations of rapidly rotating stars requires a good model of their surface effective temperature. Until now, laws of the form T_eff∝ g_eff^β have been used, but they are only valid for slowly rotating stars. Aims: We propose a simple model that can describe the latitudinal variations in the flux of rotating stars at any rotation rate. Methods: This model assumes that the energy flux is a divergence-free vector that is antiparallel to the effective gravity. Results: When mass distribution can be described by a Roche model, the latitudinal variations in the effective temperature only depend on a single parameter, namely the ratio of the equatorial velocity to the Keplerian velocity. We validate this model by comparing its predictions to those of the most realistic two-dimensional models of rotating stars issued from the ESTER code. The agreement is very good, as it is with the observations of two rapidly rotating stars, α Aql and α Leo. Conclusions: We suggest that as long as a gray atmosphere can be accepted, the inversion of data on flux distribution coming from interferometric observations of rotating stars uses such a model, which has just one free parameter.

  2. Toroidal rotation studies in KSTAR

    NASA Astrophysics Data System (ADS)

    Lee, S. G.; Lee, H. H.; Yoo, J. W.; Kim, Y. S.; Ko, W. H.; Terzolo, L.; Bitter, M.; Hill, K.; KSTAR Team

    2014-10-01

    Investigation of the toroidal rotation is one of the most important topics for the magnetically confined fusion plasma researches since it is essential for the stabilization of resistive wall modes and its shear plays an important role to improve plasma confinement by suppressing turbulent transport. The most advantage of KSTAR tokamak for toroidal rotation studies is that it equips two main diagnostics including the high-resolution X-ray imaging crystal spectrometer (XICS) and charge exchange spectroscopy (CES). Simultaneous core toroidal rotation and ion temperature measurements of different impurity species from the XICS and CES have shown in reasonable agreement with various plasma discharges in KSTAR. It has been observed that the toroidal rotation in KSTAR is faster than that of other tokamak devices with similar machine size and momentum input. This may due to an intrinsically low toroidal field ripple and error field of the KSTAR device. A strong braking of the toroidal rotation by the n = 1 non-resonant magnetic perturbations (NRMPs) also indicates these low toroidal field ripple and error field. Recently, it has been found that n = 2 NRMPs can also damp the toroidal rotation in KSTAR. The detail toroidal rotation studies will be presented. Work supported by the Korea Ministry of Science, ICT and Future Planning under the KSTAR project.

  3. Torsion-rotation intensities in methanol

    NASA Astrophysics Data System (ADS)

    Pearson, John

    Methanol exists in numerous kinds of astronomical objects featuring a wide range of local conditions. The light nature of the molecule coupled with the internal rotation of the methyl group with respect to the hydroxyl group results in a rich, strong spectrum that spans the entire far-infrared region. As a result, any modest size observational window will have a number of strong methanol transitions. This has made it the gas of choice for testing THz receivers and to extract the local physical conditions from observations covering small frequency windows. The latter has caused methanol to be dubbed the Swiss army knife of astrophysics. Methanol has been increasingly used in this capacity and will be used even more for subsequent investigations into the Herschel archive, and with SOFIA and ALMA. Interpreting physical conditions on the basis of a few methanol lines requires that the molecular data, line positions, intensities, and collision rates, be complete, consistent and accurate to a much higher level than previously required for astrophysics. The need for highly reliable data is even more critical for modeling the two classes of widespread maser action and many examples of optical pumping through the torsional bands. Observation of the torsional bands in the infrared will be a unique opportunity to directly connect JWST observations with those of Herschel, SOFIA, and ALMA. The theory for the intensities of torsion-rotation transitions in a molecule featuring a single internally rotating methyl group is well developed after 70 years of research. However, other than a recent very preliminary and not completely satisfactory investigation of a few CH3OH torsional bands, this theory has never been experimentally tested for any C3V internal rotor. More alarming is a set of recent intensity calibrated microwave measurements that showed deviations relative to calculations of up to 50% in some ground state rotational transitions commonly used by astronomers to extract

  4. Rotating polarizer and rotating retarder plate polarimeters: comparison of performances

    NASA Astrophysics Data System (ADS)

    Pelizzari, Stefano; Rovati, Luigi; De Angelis, C.

    2001-05-01

    Rotating polarizer and rotating retarder plate polarimeters are widely used in high-resolution polarimetry, for example in remote sensing, fiber optic measurements and biomedics; as a consequence the analysis of the performances of these devices is very important from the instrumental point of view. To compare the two methods, we developed a synchronous polarimeter based on a mechanically rotating stage, where a rotating Glan-Thompson linear polarizer or a wave retarder can be easily mounted. A specific design allows to acquire synchronously the intensity signals digitally process the data to extract the polarization Stokes parameters. We investigate the two cases along with their impact on measurement techniques. Performance curves are shown for various polarization input parameters and light levels. Specifically, we address issues concerning the accuracy and the systematic and statistical measuring errors. Moreover, computer simulations and measurement results are presented and discussed.

  5. Precise rotation rates for five slowly rotating A stars

    SciTech Connect

    Gray, David F.

    2014-04-01

    Projected rotation rates of five early A-type slowly rotating stars are measured spectroscopically to a precision of 0.2 km s{sup –1}. A detailed Fourier analysis is done, as well as a comparison of profiles directly. Macroturbulence is needed in addition to rotation to reproduce the profile shapes. An upper limit of ≲2 km s{sup –1} is placed on the microturbulence dispersion. Small unexplained differences between the models and the observations are seen in the sidelobe structure of the transforms. The v sin i results are: α Dra, 26.2; θ Leo, 22.5; α CMa A, 16.7; γ Gem A, 10.7; o Peg, 6.0 km s{sup –1}. These stars are suitable as standards for measuring rotation using less fundamental methods.

  6. Quantum Rotational Effects in Nanomagnetic Systems

    NASA Astrophysics Data System (ADS)

    O'Keeffe, Michael F.

    Quantum tunneling of the magnetic moment in a nanomagnet must conserve the total angular momentum. For a nanomagnet embedded in a rigid body, reversal of the magnetic moment will cause the body to rotate as a whole. When embedded in an elastic environment, tunneling of the magnetic moment will cause local elastic twists of the crystal structure. In this thesis, I will present a theoretical study of the interplay between magnetization and rotations in a variety of nanomagnetic systems which have some degree of rotational freedom. We investigate the effect of rotational freedom on the tunnel splitting of a nanomagnet which is free to rotate about its easy axis. Calculating the exact instanton of the coupled equations of motion shows that mechanical freedom of the particle renormalizes the easy axis anisotropy, increasing the tunnel splitting. To understand magnetization dynamics in free particles, we study a quantum mechanical model of a tunneling spin embedded in a rigid rotor. The exact energy levels for a symmetric rotor exhibit first and second order quantum phase transitions between states with different values the magnetic moment. A quantum phase diagram is obtained in which the magnetic moment depends strongly on the moments of inertia. An intrinsic contribution to decoherence of current oscillations of a flux qubit must come from the angular momentum it transfers to the surrounding body. Within exactly solvable models of a qubit embedded in a rigid body and an elastic medium, we show that slow decoherence is permitted if the solid is macroscopically large. The spin-boson model is one of the simplest representations of a two-level system interacting with a quantum harmonic oscillator, yet has eluded a closed-form solution. I investigate some possible approaches to understanding its spectrum. The Landau-Zener dynamics of a tunneling spin coupled to a torsional resonator show that for certain parameter ranges the system exhibits multiple Landau-Zener transitions

  7. Cooling system for rotating machine

    DOEpatents

    Gerstler, William Dwight; El-Refaie, Ayman Mohamed Fawzi; Lokhandwalla, Murtuza; Alexander, James Pellegrino; Quirion, Owen Scott; Palafox, Pepe; Shen, Xiaochun; Salasoo, Lembit

    2011-08-09

    An electrical machine comprising a rotor is presented. The electrical machine includes the rotor disposed on a rotatable shaft and defining a plurality of radial protrusions extending from the shaft up to a periphery of the rotor. The radial protrusions having cavities define a fluid path. A stationary shaft is disposed concentrically within the rotatable shaft wherein an annular space is formed between the stationary and rotatable shaft. A plurality of magnetic segments is disposed on the radial protrusions and the fluid path from within the stationary shaft into the annular space and extending through the cavities within the radial protrusions.

  8. Rotation of a magnetized plasma

    SciTech Connect

    Annaratone, B. M.; Escarguel, A.; Lefevre, T.; Rebont, C.; Claire, N.; Doveil, F.

    2011-03-15

    The plasma rotation in the axial magnetic field of the linear machine Mistral [A. Escarguel, Eur. Phys. J. D 56, 209 (2010)] is well described by the assumption that the electrons injected from the source exit radially from the central column and are subject to the Lorentz force. Electrons and ions rotate together by ambipolarity. The solution of the momentum equations foresees correctly the observed radial dependence of the ionic radial velocity measured by laser induced fluorescence. The resolution of these equations is also in good agreement with the measured dependence of the rotation frequency on the applied magnetic field and on the background pressure.

  9. Cell rotation using optoelectronic tweezers.

    PubMed

    Liang, Yuan-Li; Huang, Yuan-Peng; Lu, Yen-Sheng; Hou, Max T; Yeh, J Andrew

    2010-01-01

    A cell rotation method by using optoelectronic tweezers (OET) is reported. The binary image of a typical OET device, whose light and dark sides act as two sets of parallel plates with different ac voltages, was used to create a rotating electric field. Its feasibility for application to electrorotation of cells was demonstrated by rotating Ramos and yeast cells in their pitch axes. The electrorotation by using OET devices is dependent on the medium and cells' electrical properties, the cells' positions, and the OET device's geometrical dimension, as well as the frequency of the electric field. PMID:21267435

  10. Axial gap rotating electrical machine

    DOEpatents

    None

    2016-02-23

    Direct drive rotating electrical machines with axial air gaps are disclosed. In these machines, a rotor ring and stator ring define an axial air gap between them. Sets of gap-maintaining rolling supports bear between the rotor ring and the stator ring at their peripheries to maintain the axial air gap. Also disclosed are wind turbines using these generators, and structures and methods for mounting direct drive rotating electrical generators to the hubs of wind turbines. In particular, the rotor ring of the generator may be carried directly by the hub of a wind turbine to rotate relative to a shaft without being mounted directly to the shaft.

  11. Orbital, Rotational, and Climatic Interactions

    NASA Technical Reports Server (NTRS)

    Bills, Bruce G. (Editor)

    1992-01-01

    The report of an international meeting on the topic of Orbital, Rotational, and Climatic Interactions, which was held 9-11 Jul. 1991 at the Johns Hopkins University is presented. The meeting was attended by 22 researchers working on various aspects of orbital and rotational dynamics, paleoclimate data analysis and modeling, solid-Earth deformation studies, and paleomagnetic analyses. The primary objective of the workshop was to arrive at a better understanding of the interactions between the orbital, rotational, and climatic variations of the Earth. This report contains a brief introduction and 14 contributed papers which cover most of the topics discussed at the meeting.

  12. Rotating regular black hole solution

    NASA Astrophysics Data System (ADS)

    Abdujabbarov, Ahmadjon

    2016-07-01

    Based on the Newman-Janis algorithm, the Ayón-Beato-García spacetime metric [Phys. Rev. Lett. 80, 5056 (1998)] of the regular spherically symmetric, static, and charged black hole has been converted into rotational form. It is shown that the derived solution for rotating a regular black hole is regular and the critical value of the electric charge for which two horizons merge into one sufficiently decreases in the presence of the nonvanishing rotation parameter a of the black hole.

  13. Magnetoplasmons in rotating dusty plasmas.

    PubMed

    Hartmann, Peter; Donkó, Zoltán; Ott, Torben; Kählert, Hanno; Bonitz, Michael

    2013-10-11

    A rotating dusty plasma apparatus was constructed to provide the possibility of experimental emulation of extremely high magnetic fields by means of the Coriolis force, observable in a corotating measurement frame. We present collective excitation spectra for different rotation rates with a magnetic induction equivalent of up to 3200 T. We identify the onset of magnetoplasmon-equivalent mode dispersion in the rotating macroscopic two-dimensional single-layer dusty plasma. The experimental results are supported by molecular dynamics simulations of 2D magnetized Yukawa systems.

  14. STELLAR ROTATION PERIODS OF THE KEPLER OBJECTS OF INTEREST: A DEARTH OF CLOSE-IN PLANETS AROUND FAST ROTATORS

    SciTech Connect

    McQuillan, A.; Mazeh, T.; Aigrain, S.

    2013-09-20

    We present a large sample of stellar rotation periods for Kepler Objects of Interest, based on three years of public Kepler data. These were measured by detecting periodic photometric modulation caused by star spots, using an algorithm based on the autocorrelation function of the light curve, developed recently by McQuillan, Aigrain and Mazeh (2013). Of the 1919 main-sequence exoplanet hosts analyzed, robust rotation periods were detected for 737. Comparing the detected stellar periods to the orbital periods of the innermost planet in each system reveals a notable lack of close-in planets around rapid rotators. It appears that only slowly spinning stars with rotation periods longer than 5-10 days host planets on orbits shorter than 2 or 3 days, although the mechanism(s) that lead(s) to this is not clear.

  15. Rotating plane Couette flow at high rotation number

    NASA Astrophysics Data System (ADS)

    Suryadi, A.; Tillmark, N.; Alfredsson, P. H.

    2012-11-01

    Flow structures in the rotating plane Couette flow facility at KTH (described in Tsukahara, et al. J. Fluid Mech. vol. 648) have been studied at high rotation numbers. The test section is 20 mm wide with a length of 1500 mm in the streamwise (x) and 360 mm in the spanwise (z) directions and can be rotated in the spanwise direction up to angular velocities of Ωz ~ 0 . 6 rad/s. The flow is characterised by: (1) the Reynolds number Re based on the test section's half-width (h) and half of the velocity difference between the moving walls, (2) the rotation number Ω = 2Ωzh2 / ν . For low rotation numbers the primary instability consists of streamwise-oriented roll cells, but Tsukahara, et al. showed the secondary instability in the form of wavy streamwise oriented roll-cells at Re = 100 and Ω = 3 - 12 , whereas for higher Ω, the flow structures again stabilize to streamwise-oriented roll cells. Here we find that at even higher Ω in the range 40 - 70 , a new type of secondary instability develops in the form of counter-rotating helical roll-cells. The structure of this instability, as well as other instabilities, are investigated by flow visualization as well as two-dimensional PIV-measurements in several xz -planes.

  16. Collapsing thin shells with rotation

    NASA Astrophysics Data System (ADS)

    Delsate, Térence; Rocha, Jorge V.; Santarelli, Raphael

    2014-06-01

    We construct exact solutions describing the motion of rotating thin shells in a fully backreacted five-dimensional rotating black hole spacetime. The radial equation of motion follows from the Darmois-Israel junction conditions, where both interior and exterior geometries are taken to be equal angular momenta Myers-Perry solutions. We show that rotation generates anisotropic pressures and momentum along the shell. Gravitational collapse scenarios including rotation are analyzed and a new class of stationary solutions is introduced. Energy conditions for the anisotropic matter shell are briefly discussed. We find that the weak energy condition is not violated for the collapse scenario where the shell starts at rest from infinity, nor for the new class of stationary solutions in anti-de Sitter. We further prove that the cosmic censorship conjecture is always satisfied in our setup.

  17. Rotator cuff repair - series (image)

    MedlinePlus

    ... shoulder and arm bones. The tendons can be torn from overuse or injury. ... Surgery to repair a torn rotator cuff is usually very successful at relieving pain in the shoulder. The procedure is less predictable at returning strength ...

  18. Optical wheel-rotation sensor

    SciTech Connect

    Veeser, L.; Rodriguez, P.; Forman, P.; Deeter, M.

    1994-05-01

    We describe a fiber-optic rotation sensor based on diffraction of light in a magneto-optic crystal (BIG). Exploitation of this effect permits the construction of a sensor requiring no polarization elements or lenses.

  19. Fission of rotating fermium isotopes

    NASA Astrophysics Data System (ADS)

    Baran, A.; Staszczak, A.

    2014-05-01

    In this paper we discuss the process of fission of even fermium isotopes, on the basis of their rotational states. The nuclear intrinsic vorticity and its coupling to the global rotation of the nucleus are used to simulate the interaction between the rotational motion and the pairing field, and lead to pairing quenching in the case of higher angular momentum states. The rotation leads to a decreasing of the fission barrier heights. The ingredients of the model—ground state fission barriers, pairing correlation energies and the cranking moments of inertia—are obtained within the self-consistent Hartree-Fock-Bogoliubov framework using the Skyrme \\text{Sk}{{\\text{M}}^{*}} energy density functional. Fission barriers and half-lives are estimated for spins I up to I = 16ℏ.

  20. High performance rotational vibration isolator.

    PubMed

    Sunderland, Andrew; Blair, David G; Ju, Li; Golden, Howard; Torres, Francis; Chen, Xu; Lockwood, Ray; Wolfgram, Peter

    2013-10-01

    We present a new rotational vibration isolator with an extremely low resonant frequency of 0.055 ± 0.002 Hz. The isolator consists of two concentric spheres separated by a layer of water and joined by very soft silicone springs. The isolator reduces rotation noise at all frequencies above its resonance which is very important for airborne mineral detection. We show that more than 40 dB of isolation is achieved in a helicopter survey for rotations at frequencies between 2 Hz and 20 Hz. Issues affecting performance such as translation to rotation coupling and temperature are discussed. The isolator contains almost no metal, making it particularly suitable for electromagnetic sensors.

  1. On the compositions of rotations

    NASA Astrophysics Data System (ADS)

    Donchev, V. D.; Mladenova, C. D.; Mladenov, I. M.

    2015-10-01

    This paper discusses the problem of composition of two arbitrary rotations in SO(3,ℝ) given in their vector-parameter form. The cases when one or two half-turns are involved in the composition or the resulting rotation is a half turn receive also rigorous treatment. Technically, this is done by lifting the problem to the covering group SU(2). Systematization of the results is made and relying on them, some applications are discussed. A convenient and economic computational method for composing rotations in vector-parameter form is proposed. It is such that the composition of two arbitrary (including half-turns) rotations can be done with at most 12 multiplications. Finally, we present an explicit variant of the construction behind Cartan's theorem in the case of SO(3,ℝ).

  2. An Exercise in Rotational Motion.

    ERIC Educational Resources Information Center

    Mahoney, Brother James

    1980-01-01

    Describes an advanced high school physics experiment demonstrating rotational kinematics and dynamics, using simple equipment such as empty coffee cans, inclined planes, meter sticks, and a large 10-second demonstration timer. (CS)

  3. Rotator cuff - self-care

    MedlinePlus

    ... rotator cuff is a group of muscles and tendons that attach to the bones of the shoulder ... problems include: Tendinitis , which is irritation of the tendons and inflammation of the bursa (a normally smooth ...

  4. Rotation, differential rotation, and gyrochronology of active Kepler stars

    NASA Astrophysics Data System (ADS)

    Reinhold, Timo; Gizon, Laurent

    2015-11-01

    Context. In addition to the discovery of hundreds of exoplanets, the high-precision photometry from the CoRoT and Kepler satellites has led to measurements of surface rotation periods for tens of thousands of stars, which can potentially be used to infer stellar ages via gyrochronology. Aims: Our main goal is to derive ages of thousands of field stars using consistent rotation period measurements derived by different methods. Multiple rotation periods are interpreted as surface differential rotation (DR). We study the dependence of DR with rotation period and effective temperature. Methods: We reanalyze a previously studied sample of 24 124 Kepler stars using different approaches based on the Lomb-Scargle periodogram. Each quarter (Q1-Q14) is treated individually using a prewhitening approach. Additionally, the full time series and their different segments are analyzed. Results: For more than 18 500 stars our results are consistent with the rotation periods from McQuillan et al. (2014, ApJS, 211, 24). Of these, more than 12 300 stars show multiple significant peaks, which we interpret as DR. Dependencies of the DR with rotation period and effective temperature could be confirmed, e.g., the relative DR increases with rotation period. Gyrochronology ages between 100 Myr and 10 Gyr were derived for more than 17 000 stars using different gyrochronology relations, most of them with uncertainties dominated by period variations. We find a bimodal age distribution for Teff between 3200-4700 K. The derived ages reveal an empirical activity-age relation using photometric variability as stellar activity proxy. Additionally, we found 1079 stars with extremely stable (mostly short) periods. Half of these periods may be associated with rotation stabilized by non-eclipsing companions, the other half might be due to pulsations. Conclusions: The derived gyrochronology ages are well constrained since more than ~93.0% of the stars seem to be younger than the Sun where calibration is

  5. Effects of Clinostat Rotation on Aurelia Statolith Synthesis

    NASA Technical Reports Server (NTRS)

    Spangenberg, Dorothy B.; Davis, S.; Ross-Clunis, H., III

    1991-01-01

    Aurelia ephyrae develop eight graviceptors (rhopalia) during their metamorphosis from polyps, which are used for positional orientation with respect to gravity. In three experiments for each speed of 1/15, 1/8, 1/2, 1, and 24 rpm, groups of six polyps were rotated in the horizontal or vertical plane (control) using clinostats. Other controls were kept stationary in the two planes. Ten ephyrae from each group were collected after 5 to 6 days at 27 C in iodine and the number of statoliths per rhopalium were counted. Statistical analyses of statolith numbers revealed that horizontal clinostat rotation at 1/4 and 1/2 rpm caused the formation of significantly fewer statoliths per rhopalium than were found in controls. The finding that these slow rates of rotation reduces statolith numbers suggests that the developing ephyrae were disoriented with respect to gravity at these speeds, causing fewer statocytes to differentiate or to mineralize.

  6. Effects of clinostat rotation on Aurelia statolith synthesis

    NASA Technical Reports Server (NTRS)

    Spangenberg, D.; Davis, S.; Ross-Clunis, H., III

    1985-01-01

    Aurelia ephyrae develop eight graviceptors (rhopalia) during their metamorphosis from polyps, which are used for positional orientation with respect to gravity. In three experiments for each speed of 1/15, 1/8, 1/4, 1/2, 1, and 24 rpm, groups of six polyps were rotated in the horizontal or vertical plane (control) using clinostats. Other controls were kept stationary in the two planes. Ten ephyrae from each group were collected after 5-6 days at 27 C in iodine and the number of statoliths per rhopalium were counted. Statistical analyses of statolith numbers revealed that horizontal clinostat rotation at 1/4 and 1/2 rpm caused the formation of significantly fewer statoliths per rhopalium than were found in controls. The finding that these slow rates of rotation reduces statolith numbers suggests that the developing ephyrae were disoriented with respect to gravity at these speeds, causing fewer statocytes to differentiate or to mineralize.

  7. Nonaxisymmetric oscillations of differentially rotating relativistic stars

    SciTech Connect

    Passamonti, Andrea; Stavridis, Adamantios; Kokkotas, Kostas D.

    2008-01-15

    Nonaxisymmetric oscillations of differentially rotating stars are studied using both slow rotation and Cowling approximation. The equilibrium stellar models are relativistic polytropes where differential rotation is described by the relativistic j-constant rotation law. The oscillation spectrum is studied versus three main parameters: the stellar compactness M/R, the degree of differential rotation A, and the number of maximum couplings l{sub max}. It is shown that the rotational splitting of the nonaxisymmetric modes are strongly enhanced by increasing the compactness of the star and the degree of differential rotation. Finally, we investigate the relation between the fundamental quadrupole mode and the corotation band of differentially rotating stars.

  8. Relativity on Rotated Graph Paper

    NASA Astrophysics Data System (ADS)

    Salgado, Roberto

    2011-11-01

    We present visual calculations in special relativity using spacetime diagrams drawn on graph paper that has been rotated by 45 degrees. The rotated lines represent lightlike directions in Minkowski spacetime, and the boxes in the grid (called light-clock diamonds) represent ticks of an inertial observer's lightclock. We show that many quantitative results can be read off a spacetime diagram by counting boxes, using a minimal amount of algebra.

  9. Rotation of the planet mercury.

    PubMed

    Jefferys, W H

    1966-04-01

    The equations of motion for the rotation of Mercury are solved for the general case by an asymptotic expansion. The findings of Liu and O'Keefe, obtained by numerical integration of a special case, that it is possible for Mercury's rotation to be locked into a 2:3 resonance with its revolution, are confirmed in detail. The general solution has further applications. PMID:17741632

  10. Maximising somersault rotation in tumbling.

    PubMed

    King, M A Mark A; Yeadon, M R Maurice R

    2004-04-01

    Performing complex somersaulting skills during the flight phase of tumbling requires the generation of linear and angular momenta during the approach and takeoff phases. This paper investigates how approach characteristics and takeoff technique affect performance with a view to maximising somersault rotation in tumbling. A five-segment planar simulation model, customised to an elite gymnast, was used to produce a simulation which closely matched a recorded performance of a double layout somersault by the elite gymnast. Three optimisations were carried out to maximise somersault rotation with different sets of initial conditions. Using the same initial linear and angular momentum as the double layout somersault and varying the joint torque activation timings allowed a double straight somersault to be performed with 19% more rotation potential than the actual performance. Increasing the approach velocity to a realistic maximum of 7 ms(-1) resulted in a 42% reduction in rotation potential when the activation timings were unchanged but allowed a triple layout somersault to be performed with an increase of 31% in rotation potential when activation timings were re-optimised. Increasing also the initial angular momentum to a realistic maximum resulted in a 4% reduction in rotation potential when the activation timings were unchanged but allowed a triple straight somersault to be performed with a further increase of 9% in rotation potential when activation timings were re-optimised. It is concluded that the limiting factor to maximising somersault rotation is the ability to generate high linear and angular velocities during the approach phase coupled with the ability to adopt consonant activation timings during the takeoff phase. PMID:14996558

  11. Rotating Shadowband Spectroradiometer (RSS) Handbook

    SciTech Connect

    Kiedron, P; Schlemmer, J; Klassen, M

    2005-01-01

    The rotating shawdowband spectroradiometer (RSS) implements the same automated shadowbanding technique used by the multifilter rotating shadowband radiometer (MFRSR), and so it too provides spectrally-resolved, direct-normal, diffuse-horizontal, and total-horizontal irradiances, and can be calibrated in situ via Langley regression. The irradiance spectra are measured simultaneously at all spectral elements (pixels) in 360-nm to 1050-nm range.

  12. Rotation of Hyperion. I - Observations

    NASA Technical Reports Server (NTRS)

    Klavetter, James Jay

    1989-01-01

    Precise and well sampled observations of Hyperion over a long period of time have been performed to test the prediction of Wisdom et al. (1984) that the satellite is in a state of chaotic rotation. CCD data for a 13-week period were obtained in Chile and in Arizona. A phase-dispersion-minimization analysis of the light curve indicates that Hyperion is not in a periodic rotational state, thus suggesting that it is chaotic.

  13. The Rotation of Galaxy Clusters

    NASA Astrophysics Data System (ADS)

    Tovmassian, H. M.

    2015-09-01

    The method for detection of the galaxy cluster rotation based on the study of distribution of member galaxies with velocities lower and higher than the cluster mean velocity over the cluster image is proposed. The search for rotation is made for flat clusters with a/b > 1.8 and BMI type clusters which are expected to be rotating. For comparison there were studied also round clusters and clusters of NBMI type, the second by brightness galaxy, which does not differ significantly from the cluster cD galaxy. Seventeen out of studied 65 clusters are found to be rotating. It was found that the detection rate is sufficiently high for flat clusters, over 60%, and clusters of BMI type with dominant cD galaxy, ≈ 35% . The obtained results show that clusters were formed from the huge primordial gas clouds and preserved the rotation of the primordial clouds, unless they did not experience mergings with other clusters and groups of galaxies, as a result of which the rotation was prevented.

  14. Generation of magnetoacoustic zonal flows by Alfven waves in a rotating plasma

    SciTech Connect

    Mikhailovskii, A. B.; Lominadze, J. G.; Churikov, A. P.; Erokhin, N. N.; Tsypin, V. S.; Smolyakov, A. I.; Galvao, R. M. O.

    2007-08-15

    Analytical theory of nonlinear generation of magnetoacoustic zonal flows in a rotating plasma is developed. As the primary modes causing such a generation, a totality of the Alfven waves are considered, along with the kinetic, inertial, and rotational. It is shown that in all these cases of the Alfven waves the generation is possible if the double plasma rotation frequency exceeds the zonal flow frequency.

  15. Choice of Rotation Rate for the Horizontal Clinostat 1

    PubMed Central

    Lyon, Charles J.

    1970-01-01

    A series of nine rates of rotation of the clinostat were tested to determine optimal and acceptable conditions for simulating weightlessness in plants. Young seedlings of wheat (Triticum aestivum L.) developed roots and coleoptiles of equal lengths and with the same orientation angles over a range of rotation rates from 0.25 to 480 minutes per revolution. Rates from 0.25 to 3 minutes per revolution provided for maximal epinastic curvatures of leaves and branches of Coleus blumei Benth. except for a reduced mean curvature of branches at 0.25 minute per revolution, due probably to physical disturbances in their growth. Smaller epinastic curvatures developed in both leaves and branches rotated at 15 minutes per revolution or more slowly. Indoleacetic acid-2-14C was used for measurements of extractable radioactivity in determining the reason for smaller curvatures of Coleus branches and tomato (Lycopersicon esculentum Mill.) leaves at the rotation rate of 60 minutes per revolution than at 1 minute per revolution. The cause was determined to be movement of some auxin from the upper into the lower side of a plagiotropic leaf or branch under the transient influence of gravity during rotation on the slower clinostat. A rotation period of 1 to 3 minutes was found to be acceptable for most plants. PMID:16657466

  16. A study of rotational velocity distribution of Be stars

    NASA Astrophysics Data System (ADS)

    Sitko, C.; Janot-Pacheco, E.; Emilio, M.

    2014-10-01

    Classical Be stars are rapid rotators of spectral type late O to early A and luminosity class V-III, which exhibit Balmer emission lines and often a near infrared excess originating in an equatorially concentrated circumstellar envelope, both produced by sporadic mass ejection episodes. The causes of the abnormal mass loss (the so-called Be phenomenon) are as yet unknown. In spite of their high vsin i, rapid rotation alone cannot explain the ejection episodes as most Be stars do not rotate at their critical rotation rates. In this work we present the distribution of vsin i of 261 Be's stars from BeSS (Be Star Spectra) database. We used two techniques, the Fourier method and the FWHM (Full Width at Half Maximum) method. For the analysis we made use of three absorption lines of Helium (4026r A, 4388 Å and 4471 Å). Stars with projected rotational velocities up to 300 km s^{-1} agree with the ones already published in the literature. 84 of our stars do not have the values of rotational velocity published. The majority of our sample are B1/B2 spectral type, whose have the greatest velocities.

  17. Optical Rotation Calculations for a Set of Pyrrole Compounds.

    PubMed

    Haghdani, Shokouh; Gautun, Odd R; Koch, Henrik; Åstrand, Per-Olof

    2016-09-22

    Optical rotation of 14 molecules containing the pyrrole group is calculated by employing both time-dependent density functional theory (TDDFT) with the CAM-B3LYP functional and the second-order approximate coupled-cluster singles and doubles (CC2) method. All optical rotations have been provided using the aug-cc-pVDZ basis set at λ = 589 nm. The two methods predict similar results for both sign and magnitude for the optical rotation of all molecules. The obtained signs are consistent with experiments as well, although several conformers for four molecules needed to be studied to reproduce the experimental sign. We have also calculated excitation energies and rotatory strengths for the six lowest lying electronic transitions for several conformers of the two smallest molecules and found that each rotatory strength has various contributions for each conformer which can cause different optical rotations for different conformers of a molecule. Our results illustrate that both methods are able to reproduce the experimental optical rotations, and that the CAM-B3LYP functional, the least computationally expensive method used here, is an applicable and reliable method to predict the optical rotation for these molecules in line with previous studies. PMID:27571252

  18. Effects of rotation interval on sleepiness and circadian dynamics on forward rotating 3-shift systems.

    PubMed

    Postnova, Svetlana; Postnov, Dmitry D; Seneviratne, Martin; Robinson, Peter A

    2014-02-01

    A physiologically based mathematical model of sleep-wake cycles is used to examine the effects of shift rotation interval (RI) (i.e., the number of days spent on each shift) on sleepiness and circadian dynamics on forward rotating 3-shift schedules. The effects of the schedule start time on the mean shift sleepiness are also demonstrated but are weak compared to the effects of RI. The dynamics are studied for a parameter set adjusted to match a most common natural sleep pattern (i.e., sleep between 0000 and 0800) and for common light conditions (i.e., 350 lux of shift lighting, 200 lux of daylight, 100 lux of artificial lighting during nighttime, and 0 lux during sleep). Mean shift sleepiness on a rotating schedule is found to increase with RI, reach maximum at intermediate RI=6 d, and then decrease. Complete entrainment to shifts within the schedules is not achieved at RI≤10 d. However, circadian oscillations synchronize to the rotation cycles, with RI=1,2 d and RI≥6 d demonstrating regular periodic changes of the circadian rhythm. At rapid rotation, circadian phase stays within a small 4-h interval, whereas slow rotation leads to around-the-clock transitions of the circadian phase with constantly delayed sleep times. Schedules with RI=3-5 d are not able to entrain the circadian rhythms, even in the absence of external circadian disturbances like social commitments and days off. To understand the circadian dynamics on the rotating shift schedules, a shift response map is developed, showing the direction of circadian change (i.e., delay or advance) depending on the relation between the shift start time and actual circadian phase. The map predicts that the un-entrained dynamics come from multiple transitions between advance and delay behavior on the shifts in the schedules. These are primarily caused by the imbalance between the amount of delay and advance on the different shift types within the schedule. Finally, it is argued that shift response maps can aid in

  19. Asteroid Ida - 6 Views Showing Rotation

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This composite image shows the asteroid 243 Ida as seen from the Galileo spacecraft during its approach on August 28, 1993. The six views were shuttered through the camera's green filter and show Ida's rotation over a period of about 3 hours 18 minutes. The asteroid makes a complete rotation every 4 hours 38 minutes; therefore, this set of images spans about 3/4 of Ida's rotation period and shows most of Ida's surface. By combining the information in these views with that from the highest resolution images returned from the spacecraft in September 1993, the size and shape of this irregular body can now be determined accurately The asteroid appears to be about 58 kilometers (36 miles) long and about 23 kilometers wide, with a very irregular shape and volume of some 16,000 cubic kilometers. The images are arranged in chronological order from a time 3 hours 51 minutes before closest approach (upper left), through upper right, middle left, middle right lower left and lower right (33 minutes before closest approach). The six images show Ida at the same scale throughout. Ida's rotation axis is roughly vertical in these images, and the rotation causes the right-hand end of Ida to move toward the viewer as time progresses. The first image was taken from a range of about 171,000 km (106,000 miles) and provides an image resolution of about 1,700 meters per pixel (the highest resolution achieved for Ida is about 25 meters per pixel). The second, taken 70 minutes later, is from 119,000 kilometers, followed by 102,000 kilometers, 85,000 kilometers, 50,000 kilometers, and 25,000 kilometers. The features on Ida are less sharp in the earlier views because of the greater distances. Prominent in the middle three views is a deep depression across the short axis of the Asteroid. This feature tends to support the idea that Ida may have originally been formed from two or more separate large objects that collided softly and stuck together. Also visible in the lower left view is an

  20. The Dosimetric Impact of Prostate Rotations During Electromagnetically Guided External-Beam Radiation Therapy

    SciTech Connect

    Amro, Hanan; Hamstra, Daniel A.; Mcshan, Daniel L.; Sandler, Howard; Vineberg, Karen; Hadley, Scott; Litzenberg, Dale

    2013-01-01

    Purpose: To study the impact of daily rotations and translations of the prostate on dosimetric coverage during radiation therapy (RT). Methods and Materials: Real-time tracking data for 26 patients were obtained during RT. Intensity modulated radiation therapy plans meeting RTOG 0126 dosimetric criteria were created with 0-, 2-, 3-, and 5-mm planning target volume (PTV) margins. Daily translations and rotations were used to reconstruct prostate delivered dose from the planned dose. D{sub 95} and V{sub 79} were computed from the delivered dose to evaluate target coverage and the adequacy of PTV margins. Prostate equivalent rotation is a new metric introduced in this study to quantify prostate rotations by accounting for prostate shape and length of rotational lever arm. Results: Large variations in prostate delivered dose were seen among patients. Adequate target coverage was met in 39%, 65%, and 84% of the patients for plans with 2-, 3-, and 5-mm PTV margins, respectively. Although no correlations between prostate delivered dose and daily rotations were seen, the data showed a clear correlation with prostate equivalent rotation. Conclusions: Prostate rotations during RT could cause significant underdosing even if daily translations were managed. These rotations should be managed with rotational tolerances based on prostate equivalent rotations.

  1. Image rotation-elimination based on a retina-like sensor

    NASA Astrophysics Data System (ADS)

    Cao, Fengmei; Lin, Yabin; Bai, Tingzhu; Wang, Fan

    2015-12-01

    The pixels of a retina-like sensor are arranged in concentric rings, and the output image is given in log-polar coordinates. Thus, additional residual errors will not be produced when the output image is rotated. Therefore, retina-like sensors have obvious advantages and many prospects for applications in the fields of image rotation and rapid image rotation-elimination. In this study, a theory concerning the image rotation of a retina-like sensor is proposed, and a solution based on the theory is presented and realized for eliminating image rotation caused by camera rotation. The camera rotation angle is obtained using a microelectromechanical systems digital accelerometer and gyroscope; only the readout sequence of each row from static random-access memory must be changed to achieve image rotation-elimination. Several image rotation-elimination experiments have been performed which show that the proposed solution is simple, accurate, and rapid. This rapid image rotation-elimination method can be used in fields that require higher image rotation-elimination processing speeds.

  2. Effect of heat flux on differential rotation in turbulent convection.

    PubMed

    Kleeorin, Nathan; Rogachevskii, Igor

    2006-04-01

    We studied the effect of the turbulent heat flux on the Reynolds stresses in a rotating turbulent convection. To this end we solved a coupled system of dynamical equations which includes the equations for the Reynolds stresses, the entropy fluctuations, and the turbulent heat flux. We used a spectral tau approximation in order to close the system of dynamical equations. We found that the ratio of the contributions to the Reynolds stresses caused by the turbulent heat flux and the anisotropic eddy viscosity is of the order of approximately 10(L rho/l0)2, where l0 is the maximum scale of turbulent motions and L rho is the fluid density variation scale. This effect is crucial for the formation of the differential rotation and should be taken into account in the theories of the differential rotation of the Sun, stars, and planets. In particular, we demonstrated that this effect may cause the differential rotation which is comparable with the typical solar differential rotation.

  3. Transport-driven toroidal rotation in the tokamak edge

    NASA Astrophysics Data System (ADS)

    Stoltzfus-Dueck, T.

    2011-10-01

    The edge of H-mode tokamak plasmas without external momentum input almost always rotates toroidally in the co-current direction, which has prompted a theoretical search for non-diffusive momentum transport mechanisms. In contrast to these efforts, the present work treats a model drift-kinetic ion equation for the pedestal and SOL containing only parallel free streaming, magnetic drifts, and spatially inhomogeneous but purely diffusive transport. The solution demonstrates that passing-ion orbits and spatially inhomogeneous diffusion interact to cause a variation of the orbit-averaged diffusivities that depends on the sign of v∥, typically resulting in preferential transport of counter-current ions. If the plasma at the boundary with the core is allowed to rotate toroidally to annihilate toroidal momentum transport, the resulting pedestal-top rotation reaches experimentally relevant values and exhibits several features in qualitative agreement with experiment. It is almost always in the co-current direction, with a rate that is proportional to Ti|ped-top /BpolLTe for small qρi /LTe , thus inversely proportional to Ip in accord with Rice scaling. It is independent of the toroidal velocity and its radial gradient, representing a residual stress. The Ti|ped-top /BpolLTe scaling implies co-current spin-up at the transition to H-mode, as Ti increases and the gradient of Te steepens. Untested predictions of the model include a sensitivity of the rotation to the major-radial position of the X-point, with a more inboard X-point leading to stronger co-current rotation. Beyond intrinsic rotation predictions, comparison of heat and momentum transport reveals that neutral beam injection must be significantly unbalanced in the counter-current direction to cause zero toroidal rotation at the pedestal top. Work supported by a research fellowship from the Alexander von Humboldt Foundation.

  4. Rotationally Molded Liquid Crystalline Polymers

    NASA Technical Reports Server (NTRS)

    Rogers, Martin; Scribben, Eric; Baird, Donald; Hulcher, Bruce

    2002-01-01

    Rotational molding is a unique process for producing hollow plastic parts. Rotational molding offers low cost tooling and can produce very large parts with complicated shapes. Products made by rotational molding include water tanks with capacities up to 20,000 gallons, truck bed liners, playground equipment, air ducts, Nylon fuel tanks, pipes, toys, stretchers, kayaks, pallets, and many others. Thermotropic liquid crystalline polymers are an important class of engineering resins employed in a wide variety of applications. Thermotropic liquid crystalline polymers resins are composed of semirigid, nearly linear polymeric chains resulting in an ordered mesomorphic phase between the crystalline solid and the isotropic liquid. Ordering of the rigid rod-like polymers in the melt phase yields microfibrous, self-reinforcing polymer structures with outstanding mechanical and thermal properties. Rotational molding of liquid crystalline polymer resins results in high strength and high temperature hollow structures useful in a variety of applications. Various fillers and reinforcements can potentially be added to improve properties of the hollow structures. This paper focuses on the process and properties of rotationally molded liquid crystalline polymers. This paper will also highlight the interactions between academia and small businesses in developing new products and processes.

  5. Transitions in turbulent rotating convection

    NASA Astrophysics Data System (ADS)

    Rajaei, Hadi; Alards, Kim; Kunnen, Rudie; Toschi, Federico; Clercx, Herman; Fluid Dynamics Lab Team

    2015-11-01

    This study aims to explore the flow transition from one state to the other in rotating Rayleigh-Bènard convection using Lagrangian acceleration statistics. 3D particle tracking velocimetry (3D-PTV) is employed in a water-filled cylindrical tank of equal height and diameter. The measurements are performed at the center and close to the top plate at a Rayleigh number Ra = 1.28e9 and Prandtl number Pr = 6.7 for different rotation rates. In parallel, direct numerical simulation (DNS) has been performed to provide detailed information on the boundary layers. We report the acceleration pdfs for different rotation rates and show how the transition from weakly to strongly rotating Rayleigh-Bènard affects the acceleration pdfs in the bulk and boundary layers. We observe that the shapes of the acceleration PDFs as well as the isotropy in the cell center are largely unaffected while crossing the transition point. However, acceleration pdfs at the top show a clear change at the transition point. Using acceleration pdfs and DNS data, we show that the transition between turbulent states is actually a boundary layer transition between Prandtl-Blasius type (typical of non-rotating convection) and Ekman type.

  6. Rotationally Molded Liquid Crystalline Polymers

    NASA Technical Reports Server (NTRS)

    Rogers, Martin; Stevenson, Paige; Scribben, Eric; Baird, Donald; Hulcher, Bruce

    2002-01-01

    Rotational molding is a unique process for producing hollow plastic parts. Rotational molding offers advantages of low cost tooling and can produce very large parts with complicated shapes. Products made by rotational molding include water tanks with capacities up to 20,000 gallons, truck bed liners, playground equipment, air ducts, Nylon fuel tanks, pipes, toys, stretchers, kayaks, pallets, and many others. Thermotropic liquid crystalline polymers are an important class of engineering resins employed in a wide variety of applications. Thermotropic liquid crystalline polymers resins are composed of semi-rigid, nearly linear polymeric chains resulting in an ordered mesomorphic phase between the crystalline solid and the isotropic liquid. Ordering of the rigid rod-like polymers in the melt phase yields microfibrous, self-reinforcing polymer structures with outstanding mechanical and thermal properties. Rotational molding of liquid crystalline polymer resins results in high strength and high temperature hollow structures useful in a variety of applications. Various fillers and reinforcements can potentially be added to improve properties of the hollow structures. This paper focuses on the process and properties of rotationally molded liquid crystalline polymers.

  7. Rapidly rotating neutron star progenitors

    NASA Astrophysics Data System (ADS)

    Postnov, K. A.; Kuranov, A. G.; Kolesnikov, D. A.; Popov, S. B.; Porayko, N. K.

    2016-08-01

    Rotating proto-neutron stars can be important sources of gravitational waves to be searched for by present-day and future interferometric detectors. It was demonstrated by Imshennik that in extreme cases the rapid rotation of a collapsing stellar core may lead to fission and formation of a binary proto-neutron star which subsequently merges due to gravitational wave emission. In the present paper, we show that such dynamically unstable collapsing stellar cores may be the product of a former merger process of two stellar cores in a common envelope. We applied population synthesis calculations to assess the expected fraction of such rapidly rotating stellar cores which may lead to fission and formation of a pair of proto-neutron stars. We have used the BSE population synthesis code supplemented with a new treatment of stellar core rotation during the evolution via effective core-envelope coupling, characterized by the coupling time, τc. The validity of this approach is checked by direct MESA calculations of the evolution of a rotating 15 M⊙ star. From comparison of the calculated spin distribution of young neutron stars with the observed one, reported by Popov and Turolla, we infer the value τc ≃ 5 × 105 years. We show that merging of stellar cores in common envelopes can lead to collapses with dynamically unstable proto-neutron stars, with their formation rate being ˜0.1 - 1% of the total core collapses, depending on the common envelope efficiency.

  8. Spline screw multiple rotations mechanism

    NASA Technical Reports Server (NTRS)

    Vranish, John M. (Inventor)

    1993-01-01

    A system for coupling two bodies together and for transmitting torque from one body to another with mechanical timing and sequencing is reported. The mechanical timing and sequencing is handled so that the following criteria are met: (1) the bodies are handled in a safe manner and nothing floats loose in space, (2) electrical connectors are engaged as long as possible so that the internal processes can be monitored throughout by sensors, and (3) electrical and mechanical power and signals are coupled. The first body has a splined driver for providing the input torque. The second body has a threaded drive member capable of rotation and limited translation. The embedded drive member will mate with and fasten to the splined driver. The second body has an embedded bevel gear member capable of rotation and limited translation. This bevel gear member is coaxial with the threaded drive member. A compression spring provides a preload on the rotating threaded member, and a thrust bearing is used for limiting the translation of the bevel gear member so that when the bevel gear member reaches the upward limit of its translation the two bodies are fully coupled and the bevel gear member then rotates due to the input torque transmitted from the splined driver through the threaded drive member to the bevel gear member. An output bevel gear with an attached output drive shaft is embedded in the second body and meshes with the threaded rotating bevel gear member to transmit the input torque to the output drive shaft.

  9. Shapes for rotating airfoils

    NASA Technical Reports Server (NTRS)

    Bingham, G. J. (Inventor)

    1984-01-01

    An airfoil which has particular application to the blade or blades of rotor aircraft and aircraft propellers is presented. The airfoil thickness distribution, camber and leading edge radius are shaped to locate the airfoil crest at a more aft position along the chord, and to increase the freestream Mach number at which sonic flow is attained at the airfoil crest. The reduced slope of the airfoil causes a reduction in velocity at the airfoil crest at lift coefficients from zero to the maximum lift coefficient. The leading edge radius is adjusted so that the maximum local Mach number at 1.25 percent chord and at the designed maximum lift coefficient is limited to about 0.48 when the Mach number normal to the leading edge is approximately 0.20. The lower surface leading edge radius is shaped so that the maximum local Mach number at the leading edge is limited to about 0.29 when the Mach number normal to the leading edge is approximately 0.20. The drag divergence Mach number associated with the airfoil is moved to a higher Mach number over a range of lift coefficients resulting in superior aircraft performance.

  10. Instabilities in coaxial rotating jets

    NASA Astrophysics Data System (ADS)

    Ivanic, Tanja; Foucault, Eric; Pecheux, Jean; Gilard, Virginie

    2000-12-01

    The aim of this study is the characterization of the cylindrical mixing layer resulting from the interaction of two coaxial swirling jets. The experimental part of this study was performed in a cylindrical water tunnel, permitting an independent rotation of two coaxial jets. The rotations are generated by means of 2×36 blades localized in two swirling chambers. As expected, the evolution of the main instability modes presents certain differences compared to the plane-mixing-layer case. Experimental results obtained by tomography showed the existence of vortex rings and streamwise vortex pairs in the near field region. This method also permitted the observation of the evolution and interaction of different modes. PIV velocity measurements realized in the meridian plans and the plans perpendicular to the jet axis show that rotation distorts the typical top-hat axial velocity profile. The transition of the axial velocity profile from jet-like into wake-like is also observed.

  11. Rotating Rayleigh-Taylor turbulence

    NASA Astrophysics Data System (ADS)

    Boffetta, G.; Mazzino, A.; Musacchio, S.

    2016-09-01

    The turbulent Rayleigh-Taylor system in a rotating reference frame is investigated by direct numerical simulations within the Oberbeck-Boussinesq approximation. On the basis of theoretical arguments, supported by our simulations, we show that the Rossby number decreases in time, and therefore the Coriolis force becomes more important as the system evolves and produces many effects on Rayleigh-Taylor turbulence. We find that rotation reduces the intensity of turbulent velocity fluctuations and therefore the growth rate of the temperature mixing layer. Moreover, in the presence of rotation the conversion of potential energy into turbulent kinetic energy is found to be less effective, and the efficiency of the heat transfer is reduced. Finally, during the evolution of the mixing layer we observe the development of a cyclone-anticyclone asymmetry.

  12. Wormhole shadows in rotating dust

    NASA Astrophysics Data System (ADS)

    Ohgami, Takayuki; Sakai, Nobuyuki

    2016-09-01

    As an extension of our previous work, which investigated the shadows of the Ellis wormhole surrounded by nonrotating dust, in this paper we study wormhole shadows in a rotating dust flow. First, we derive steady-state solutions of slowly rotating dust surrounding the wormhole by solving relativistic Euler equations. Solving null geodesic equations and radiation transfer equations, we investigate the images of the wormhole surrounded by dust for the above steady-state solutions. Because the Ellis wormhole spacetime possesses unstable circular orbits of photons, a bright ring appears in the image, just as in Schwarzschild spacetime. The bright ring looks distorted due to rotation. Aside from the bright ring, there appear weakly luminous complex patterns by the emission from the other side of the throat. These structure could be detected by high-resolution very-long-baseline-interferometry observations in the near future.

  13. Rotational Raman scattering (Ring effect) in satellite backscatter ultraviolet measurements

    NASA Astrophysics Data System (ADS)

    Cebula, Richard P.; Joiner, Joanna; Bhartia, Pawan K.; Hilsenrath, Ernest; McPeters, Richard D.; Park, Hongwoo

    1995-07-01

    A detailed radiative transfer calculation has been carried out to estimate the effects of rotational Raman scattering (RRS) on satellite measurements of backscattered ultraviolet radiation. Raman-scattered light is shifted in frequency from the incident light, which causes filling in of solar Fraunhofer lines in the observed backscattered spectrum (also known as the Ring effect). The magnitude of the rotational Raman scattering filling in is a function of wavelength, solar zenith angle, surface reflectance, surface pressure, and instrument spectral resolution. The filling in predicted by our model is found to be in agreement with observations from the Shuttle Solar Backscatter Ultraviolet Radiometer and the Nimbus-7 Solar Backscatter Ultraviolet Radiometer.

  14. Plasma rotation and rf heating in DIII-D

    SciTech Connect

    DeGrassie, J. S.; Baker, D. R.; Burrell, K. H.; Greenfield, C. M.; Lin-Liu, Y. R.; Luce, T. C.; Petty, C. C.; Prater, R.; Heidbrink, W. W.; Rice, B. W.

    1999-09-20

    In a variety of discharge conditions on DIII-D it is observed that rf electron heating reduces the toroidal rotation speed and core ion temperature. The rf heating can be with either fast wave or electron cyclotron heating and this effect is insensitive to the details of the launched toroidal wavenumber spectrum. To date all target discharges have rotation first established with co-directed neutral beam injection. A possible cause is enhanced ion momentum and thermal diffusivity due to electron heating effectively creating greater anomalous viscosity. Another is that a counter directed toroidal force is applied to the bulk plasma via rf driven radial current.

  15. Plasma rotation and rf heating in DIII-D

    SciTech Connect

    Grassie, J. S. de; Baker, D. R.; Burrell, K. H.; Greenfield, C. M.; Lin-Liu, Y. R.; Luce, T. C.; Petty, C. C.; Prater, R.; Heidbrink, W. W.; Rice, B. W.

    1999-09-20

    In a variety of discharge conditions on DIII-D it is observed that rf electron heating reduces the toroidal rotation speed and core ion temperature. The rf heating can be with either fast wave or electron cyclotron heating and this effect is insensitive to the details of the launched toroidal wavenumber spectrum. To date all target discharges have rotation first established with co-directed neutral beam injection. A possible cause is enhanced ion momentum and thermal diffusivity due to electron heating effectively creating greater anomalous viscosity. Another is that a counter directed toroidal force is applied to the bulk plasma via rf driven radial current. (c) 1999 American Institute of Physics.

  16. Coulomb motor by rotation of spherical conductors via the electrostatic force

    NASA Astrophysics Data System (ADS)

    Wistrom, Anders O.; Khachatourian, Armik V. M.

    2002-04-01

    Three spherical conductors fixed in space and held at constant potential produces a rotational force that causes the conductors to rotate about their axis. The motor is described by an expression for the moment of force given by Coulomb's law complemented by Gauss' law of the electric potential. The observed rotation is likely to be general and apply to machines of all size scales where the electrostatic force is the dominant operative force. This would include systems ranging in size from molecular to macroscopic and be useful for devices that require rotational motion.

  17. Experimental and numerical investigation of energy dissipation in elastomeric rotational joint under harmonic loading

    NASA Astrophysics Data System (ADS)

    Jrad, Hanen; Dion, Jean Luc; Renaud, Franck; Tawfiq, Imad; Haddar, Mohamed

    2016-10-01

    This paper focuses on energy losses caused by inner damping and friction in an elastomeric rotational joint. A description of the design of a new experimental device intended to characterize dynamic stiffness in rotational elastomeric joint is presented. An original method based on Lagrange's equations, which allows accurately measuring forces and torques only with accelerometers, is proposed in order to identify dissipated energy in the rotational elastomeric joint. A rheological model developed taking into account dependence of the torque and the angular displacement (rotation). Experimental results and simulations used to quantify the dissipated energy in order to evaluate the damping ratio are presented and discussed.

  18. Rotationally actuated prosthetic helping hand

    NASA Technical Reports Server (NTRS)

    Norton, William E. (Inventor); Belcher, Jewell G., Jr. (Inventor); Carden, James R. (Inventor); West, Thomas W. (Inventor)

    1991-01-01

    A prosthetic device has been developed for below-the-elbow amputees. The device consists of a cuff, a stem, a housing, two hook-like fingers, an elastic band for holding the fingers together, and a brace. The fingers are pivotally mounted on a housing that is secured to the amputee's upper arm with the brace. The stem, which also contains a cam, is rotationally mounted within the housing and is secured to the cuff, which fits over the amputee's stump. By rotating the cammed stem between the fingers with the lower arm, the amputee can open and close the fingers.

  19. The rotational spectrum of tyrosine.

    PubMed

    Pérez, Cristóbal; Mata, Santiago; Cabezas, Carlos; López, Juan C; Alonso, José L

    2015-04-23

    In this work neutral tyrosine has been generated in the gas phase by laser ablation of solid samples, and its most abundant conformers characterized through their rotational spectra. Their identification has been made by comparison between the experimental and ab initio values of the rotational and quadrupole coupling constants. Both conformers are stabilized by an O-H•••N hydrogen bond established within the amino acid skeleton chain and an additional weak N-H•••π hydrogen bond. The observed conformers differ in the orientation of the phenolic -OH group.

  20. Butterflies with rotation and charge

    NASA Astrophysics Data System (ADS)

    Reynolds, Alan P.; Ross, Simon F.

    2016-11-01

    We explore the butterfly effect for black holes with rotation or charge. We perturb rotating BTZ and charged black holes in 2 + 1 dimensions by adding a small perturbation on one asymptotic region, described by a shock wave in the spacetime, and explore the effect of this shock wave on the length of geodesics through the wormhole and hence on correlation functions. We find the effect of the perturbation grows exponentially at a rate controlled by the temperature; dependence on the angular momentum or charge does not appear explicitly. We comment on issues affecting the extension to higher-dimensional charged black holes.

  1. Blast waves in rotating media.

    NASA Technical Reports Server (NTRS)

    Rossner, L. F.

    1972-01-01

    The model investigated involves a cylindrically symmetric blast wave generated by an infinitely long line explosion in a cold and homogeneous gas rotating rigidly in its self-gravitational field. It is found that within the context of rotation in a gravitational field a blast wave will not adopt the one-zone form familiar from similarity solutions but, rather, a two-zone form. The inner compression zone arises as a response to the presence of the restoring force, which drives a rarefaction wave into the outer compression zone.

  2. Aerofoil characteristics of rotating blades

    NASA Astrophysics Data System (ADS)

    Milborrow, D. T.; Ross, J. N.

    1985-03-01

    To assess the possibilities of using wind turbine models of modest size for studies of aerodynamic performance and wakes, a study to measure, as directly as possible from rotating blades, angles of attack and the corresponding lift coefficients, using, respectively, the nonintrusive properties of laser anemometery, and small total pressure probes with a wide angle of acceptance was initiated. Measurements at radial stations on a rotating model wind turbine blade yield lift coefficients higher than two dimensional values in the post-stall region, less than fan test results. The study yields drag coefficients higher than two dimensional values, but this may be a function of the small scale of the experiment.

  3. Libration in the earth's rotation

    NASA Technical Reports Server (NTRS)

    Chao, B. F.; Liu, H. S.; Dong, D. N.; Herring, T. A.

    1991-01-01

    External luni-solar torque exerted on the difference (B-A) of the earth's two equatorial principal moments of inertia gives rise to two types of librational motions in the earth's rotation: the semidiurnal libration in spin and the prograde diurnal libration in polar motion. Formulas for the librations considering a realistic earth model and their tidal decompositions are derived and evaluated. The spin libration has a maximum peal-to-peak amplitude of 0.90 milliarcseconds, that of the polar libration is 0.06 milliarcseconds. Implications concerning their detectability and role in the tidal variation of earth rotation are discussed.

  4. Energy Transfer in Rotating Turbulence

    NASA Technical Reports Server (NTRS)

    Cambon, Claude; Mansour, Nagi N.; Godeferd, Fabien S.; Rai, Man Mohan (Technical Monitor)

    1995-01-01

    The influence or rotation on the spectral energy transfer of homogeneous turbulence is investigated in this paper. Given the fact that linear dynamics, e.g. the inertial waves regime tackled in an RDT (Rapid Distortion Theory) fashion, cannot Affect st homogeneous isotropic turbulent flow, the study of nonlinear dynamics is of prime importance in the case of rotating flows. Previous theoretical (including both weakly nonlinear and EDQNM theories), experimental and DNS (Direct Numerical Simulation) results are gathered here and compared in order to give a self-consistent picture of the nonlinear effects of rotation on tile turbulence. The inhibition of the energy cascade, which is linked to a reduction of the dissipation rate, is shown to be related to a damping due to rotation of the energy transfer. A model for this effect is quantified by a model equation for the derivative-skewness factor, which only involves a micro-Rossby number Ro(sup omega) = omega'/(2(OMEGA))-ratio of rms vorticity and background vorticity as the relevant rotation parameter, in accordance with DNS and EDQNM results fit addition, anisotropy is shown also to develop through nonlinear interactions modified by rotation, in an intermediate range of Rossby numbers (Ro(omega) = (omega)' and Ro(omega)w greater than 1), which is characterized by a marco-Rossby number Ro(sup L) less than 1 and Ro(omega) greater than 1 which is characterized by a macro-Rossby number based on an integral lengthscale L and the micro-Rossby number previously defined. This anisotropy is mainly an angular drain of spectral energy which tends to concentrate energy in tile wave-plane normal to the rotation axis, which is exactly both the slow and the two-dimensional manifold. In Addition, a polarization of the energy distribution in this slow 2D manifold enhances horizontal (normal to the rotation axis) velocity components, and underlies the anisotropic structure of the integral lengthscales. Finally is demonstrated the

  5. Rotating head and piston engine

    SciTech Connect

    Gomm, T.J.; Messick, N.C.

    1992-07-21

    This patent describes a rotary piston combustion engine. It comprises a housing means, an engine block housing a single toroidal bore, a piston carrier ring spaced outwardly along the entire perimeter of the toroidal bore with at least one finger extending inwardly for piston attachment, a power transfer cylinder, a power output shaft, an auxiliary shaft with driven gearing means meshing with the driving gearing means, a rotating head with windows for piston passage, a trapezoidal porting means in the engine block and in the rotating head, an exhaust port means.

  6. Optimal rotation sequences for active perception

    NASA Astrophysics Data System (ADS)

    Nakath, David; Rachuy, Carsten; Clemens, Joachim; Schill, Kerstin

    2016-05-01

    One major objective of autonomous systems navigating in dynamic environments is gathering information needed for self localization, decision making, and path planning. To account for this, such systems are usually equipped with multiple types of sensors. As these sensors often have a limited field of view and a fixed orientation, the task of active perception breaks down to the problem of calculating alignment sequences which maximize the information gain regarding expected measurements. Action sequences that rotate the system according to the calculated optimal patterns then have to be generated. In this paper we present an approach for calculating these sequences for an autonomous system equipped with multiple sensors. We use a particle filter for multi- sensor fusion and state estimation. The planning task is modeled as a Markov decision process (MDP), where the system decides in each step, what actions to perform next. The optimal control policy, which provides the best action depending on the current estimated state, maximizes the expected cumulative reward. The latter is computed from the expected information gain of all sensors over time using value iteration. The algorithm is applied to a manifold representation of the joint space of rotation and time. We show the performance of the approach in a spacecraft navigation scenario where the information gain is changing over time, caused by the dynamic environment and the continuous movement of the spacecraft

  7. Polarization Properties of Rotation Powered Pulsars

    NASA Technical Reports Server (NTRS)

    Harding Alice K.

    2009-01-01

    Polarization measurements of rotation-powered pulsars and their nebulae have unique diagnostic potential. The polarization position angle of the pulsar wind nebula, as is know for the Crab pulsar, can tell us the orientation of the spin axis. Phase-resolved polarimetry of pulsars has had enormous diagnostic capability at radio and optical wavelengths and could also be a powerful diagnostic in the X-ray range. Measurement of the polarization properties as a function of pulse phase can therefore provide a multidimensional mapping of the pulsar emission. In the 'rotating vector' model, radiation originating near a magnetic pole is expected to show a characteristic S-shaped swing of the position angle vs. pulse phase. In this case it is possible to determine the magnetic inclination and viewing angles. Radiation originating further from the poles or further above the neutron star surface will have a more complex polarization signature, as a result of relativistic effects of aberration and time-of-flight delays and may also cause depolarization of the signal. I will discuss predicted polarization properties of pulsed emission in polar cap models, where radiation originates near the neutron star surface at the magnetic poles, and in slot gap and outer gap models, where radiation originates over a range of altitudes out to the speed-of-light cylinder.

  8. Climate model studies of synchronously rotating planets.

    PubMed

    Joshi, Manoj

    2003-01-01

    M stars constitute 75% of main sequence stars though, until recently, their star systems have not been considered suitable places for habitable planets to exist. In this study the climate of a synchronously rotating planet around an M dwarf star is evaluated using a three-dimensional global atmospheric circulation model. The presence of clouds and evaporative cooling at the surface of the planet result in a cooler surface temperature at the subsolar point. Water ice forms at the polar regions and on the dark side, where the minimum temperature lies between -30 degrees C and 0 degrees C. As expected, rainfall is extremely high on the starlit side and extremely low on the dark side. The presence of a dry continent causes higher temperatures on the dayside, and allows accumulation of snow on the nightside. The absence of any oceans leads to higher day-night temperature differences, consistent with previous work. The present study reinforces recent conclusions that synchronously rotating planets within the circumstellar habitable zones of M dwarf stars should be habitable, and therefore M dwarf systems should not be excluded in future searches for exoplanets.

  9. How rotational vortices enhance transfers

    NASA Astrophysics Data System (ADS)

    Griffani, D.; Rognon, P.; Metzger, B.; Einav, I.

    2013-09-01

    Inspired by recent observations of granular flow, we examine how rotational vortices contribute to heat or mass transfer enhancement in a fluid. We use a tracer method to simulate both diffusion and advection in systems of differing intrinsic diffusivities D0, vortex sizes R, vortex rotation frequencies f, and vortex lifetimes ℓ. The results reveal that these systems exhibit an effective diffusive behavior, characterized by an effective diffusivity Deff. A striking finding is the existence of two regimes, dichotomised by the Péclet number Pe = R2f/D0. When the Péclet number is less than one, there is no transfer enhancement, Deff = D0. For higher values, vortices produce some transfer enhancement with a corresponding power law Deff/D0 ≈ Pen. The power n ranges from a lower bound of 0.5 for stationary vortices of lifetime infinity, to an upper bound of 1 for vortices of lifetimes shorter than half a rotation. This difference is attributed to two different internal mechanisms involving the coupling of diffusion and advection. These results could provide new insights on the transfer properties of fluid systems comprising rotational vortices, such as granular materials, suspensions, foams, and emulsions, as well as low Reynolds number stirred flows.

  10. Holder for rotating glass body

    DOEpatents

    Kolleck, Floyd W.

    1978-04-04

    A device is provided for holding and centering a rotating glass body such as a rod or tube. The device includes a tubular tip holder which may be held in a lathe chuck. The device can utilize a variety of centering tips each adapted for a particular configuration, such as a glass O-ring joint or semi-ball joint.

  11. An Assigned Teaching Resident Rotation

    ERIC Educational Resources Information Center

    Daniels-Brady, Catherine; Rieder, Ronald

    2010-01-01

    Objective: The authors' adult psychiatry residency training program identified several educational needs for residents at their institution. Junior residents needed enhanced learning of clinical interviewing skills and learning connected to the inpatient psychiatry ward rotations, and senior residents needed opportunities to prepare for the…

  12. Rotating Cylinder Treatment System Demonstration

    EPA Science Inventory

    In August 2008, a rotating cylinder treatment system (RCTSTM) demonstration was conducted near Gladstone, CO. The RCTSTM is a novel technology developed to replace the aeration/oxidation and mixing components of a conventional lime precipitation treatment s...

  13. Meniscus Stability in Rotating Systems

    NASA Astrophysics Data System (ADS)

    Reichel, Yvonne; Dreyer, Michael

    2013-11-01

    In this study, the stability of free surfaces of fluid between two rotating coaxial, circular disks is examined. Radially mounted baffles are used to form menisci of equal size. To the center of the upper disk, a tube is connected in which a separate meniscus is formed. Assuming solid-body rotation and ignoring dynamic effects, it is observed that the free surfaces between the disks fail to remain stable once the rotation speed exceeds a critical value. In other words, Rayleigh-Taylor instability ensues when the capillary forces fail to balance centrifugal forces. Dimensionless critical rotation speeds are studied by means of the Surface Evolver via SE-FIT for varied number of baffles, the normalized distance between the disks, and the normalized central tube radius. Drop tower tests are performed to confirm some of the numerical results. The computation also reveals that there are different modes of instability as a function of the relevant parameters. This study was funded by the space agency of the German Aerospace Center with resources of the Federal Ministry of Economics and Technology on the basis of a resolution of the German Bundestag under grant number 50 RL 1320.

  14. Rotating Intershaft Brush Seal Project

    NASA Technical Reports Server (NTRS)

    Krawiecki, Stephen; Mehta, Jayesh; Holloway, Gary

    2006-01-01

    The pursuit of high Mach number flight presents several challenges to the airframe and engine design engineers. Most obvious is the resulting high temperatures encountered as the aircraft approaches Mach 3 and above. The encountered high temperatures and shaft speeds of engines require rethinking in the areas of material selections, component design and component operating life. In the area of sump compartment sealing, one of the most difficult sealing applications is the sealing of an engine s rear sump. Normally this sump will need some method of sealing between two rotating shafts. This sealing operation is done with an intershaft seal. The aft sump region also presents an additional design requirement for the intershaft seal. This region has to absorb the engine s thermal growth, which means that in the seal area, axial movement, on the order of 0.30 in., between the rotating shafts must be tolerated. A new concept or new technology of sealing an intershaft sump configuration is being developed. This concept, called a rotating intershaft brush seal has key attributes that will allow this seal to perform better, in the demanding environment of sealing an aft sump with two rotating shafts, when compared to today s sealing technology of labyrinth and carbon sea

  15. Rotations in a Vertebrate Setting

    NASA Astrophysics Data System (ADS)

    McCollum, Gin

    2003-05-01

    Rotational movements of the head are often considered to be measured in a single three dimensional coordinate system implemented by the semicircular canals of the vestibular system of the inner ear. However, the vertebrate body -- including the nervous system -- obeys rectangular symmetries alien to rotation groups. At best, nervous systems mimic the physical rotation group in a fragmented way, only partially reintegrating physical movements in whole organism responses. The vestibular canal reference frame is widely used in nervous systems, for example by eye movements. It is used to some extent even in the cerebrum, as evidenced by the remission of hemineglect -- in which half of space is ignored -- when the vestibular system is stimulated. However, reintegration of space by the organism remains incomplete. For example, compensatory eye movements (which in most cases aid visual fixation) may disagree with conscious self-motion perception. In addition, movement-induced nausea, illusions, and cue-free perceptions demonstrate symmetry breaking or incomplete spatial symmetries. As part of a long-term project to investigate rotation groups in nervous systems, we have analyzed the symmetry group of a primary vestibulo-spinal projection.

  16. Portable rotating discharge plasma device

    NASA Astrophysics Data System (ADS)

    Dwyer, B. L.; Brooks, N. H.; Lee, R. L.

    2011-10-01

    We constructed two devices for the purpose of educational demonstration: a rotating tube containing media of two densities to demonstrate axial confinement and a similar device that uses pressure variation to convert a long plasma glow discharge into a long straight arc. In the first device, the buoyant force is countered by the centripetal force, which confines less dense materials to the center of the column. Similarly, a plasma arc heats the gas through which it passes, creating a hot gaseous bubble that is less dense than the surrounding medium. Rotating its containment envelope stabilizes this gas bubble in an analogous manner to an air bubble in a rotating tube of water. In addition to stabilization, the rotating discharge also exhibits a decrease in buoyancy-driven convection currents. This limits the power loss to the walls, which decreases the field strength requirement for maintaining the arc. These devices demonstrate principles of electrodynamics, plasma physics, and fluid mechanics. They are portable and safe for classroom use. Work supported by US DOE under DE-FC02-04ER54698 and the National Undergraduate Fellowship in Fusion Science and Engineering.

  17. Hydrogen rotation-vibration oscillator

    DOEpatents

    Rhodes, C.K.

    1974-01-29

    A laser system is described wherein molecular species of hydrogen and hydrogen isotopes are induced to oscillate on rotational-vibrational levels by subjecting the hydrogen to a transverse beam of electrons of a narrowly defined energy between about 1 and 5 eV, thereby producing high intensity and high energy output. (Official Gazette)

  18. ENGINEERING BULLETIN: ROTATING BIOLOGICAL CONTACTORS

    EPA Science Inventory

    Rotating biological contactors employ aerobic fixed-film treatment to degrade either organic and/or nitrogenous (ammonia-nitrogen) constituents present in aqueous waste streams. ixed-film systems provide a surface to which the biomass can adhere. Treatment is achieved as the wast...

  19. Rotational dynamics with geometric algebra

    NASA Technical Reports Server (NTRS)

    Hestenes, D.

    1983-01-01

    A new spinor formulation of rotational dynamics is developed. A general theorem is established reducing the theory of the symmetric top to that of the spherical top. The classical problems of Lagrange and Poinsot are treated in detail, along with a modern application to the theory of magnetic resonance.

  20. Rotating drum variable depth sampler

    SciTech Connect

    Nance, Thomas A.; Steeper, Timothy J.

    2008-07-01

    A sampling device for collecting depth-specific samples in silt, sludge and granular media has three chambers separated by a pair of iris valves. Rotation of the middle chamber closes the valves and isolates a sample in a middle chamber.

  1. A formulation for aircraft rotation

    SciTech Connect

    Boland, N.

    1994-12-31

    The aircraft rotation problem arises in airline operations: the flight legs to be flown by a particular type of aircraft must be sequenced, with the intention that any one aircraft could fly through the entire sequence and end up positioned so as to begin the sequence again, hence the use of the term {open_quotes}rotation{close_quotes}. A rotation must be constructed so that at regular intervals the aircraft can undergo maintenance. This requires a particular location and duration of time. For each pair of legs which can be adjacent in the rotation, there is an associated value, called the {open_quotes}through-value{close_quotes}, which represents the revenue possibilities of providing one-stop service on these legs. We model this problem on a digraph: we need to find a Hamiltonian cycle that maximizes total through-value, subject to the side constraints arising from the maintenance requirements. We present a set partitioning formulation in which column generation involves finding a shortest path in a network, subject to side constraints.

  2. Barrier penetration and rotational damping of thermally excited superdeformed nuclei

    NASA Astrophysics Data System (ADS)

    Yoshida, K.; Matsuo, M.; Shimizu, Y. R.

    2001-12-01

    We construct a microscopic model of thermally excited superdeformed states that describes both the barrier penetration mechanism, leading to the decay-out transitions to normal deformed states, and the rotational damping causing fragmentation of rotational E2 transitions. We describe the barrier penetration by means of a tunneling path in the two-dimensional deformation energy surface, which is calculated with the cranked Nilsson-Strutinsky model. The individual excited superdeformed states and associated E2 transition strengths are calculated by the shell-model diagonalization of the many-particle-many-hole excitations interacting with the delta-type residual two-body force. The effects of the decay-out on the excited superdeformed states are discussed in detail for 152Dy, 143Eu and 192Hg. The model predicts that the decay-out brings about a characteristic decrease in the effective number of excited superdeformed rotational bands.

  3. Non-rotating and rotating radiative-convective equilibrium

    NASA Astrophysics Data System (ADS)

    Zhou, Wenyu

    Radiative-convective equilibrium (RCE), in which the radiative cooling in the atmosphere is balanced by the convective heating in a horizontally homogeneous environment, is a good starting point for studying tropical convection. It also provides an idealized framework to compare analogous simulations by global climate models (GCMs) which rely on convective parameterizations, and cloud-resolving models (CRMs) which aim to explicitly resolve moist convection. In this work, we seek to further our understanding of tropical cyclones and convective aggregation in the idealized framework of non-rotating and rotating RCE with both types of models. First, we achieve rotating RCE by coupling the resolution and physics of a GCM to rotating hydrostatic dynamics. A large doubly-periodic f-plane is used to allow multiple tropical cyclones (TCs) to coexist. Both cases with fixed and coupled sea surface temperature (SST) are considered. For fixed SST, the sensitivity to environmental parameters is investigated. Particularly, we find that the intensity, radius of maximum wind and size of TCs increase with SST. For coupled SST, SST is predicted using a simple slab ocean model. The effect of the eyewall cooling on TC intensity is studied. We show that Potential-Intensity theory overestimates the impact of the eyewall cooling on TC intensity, as its key assumption that entropy is well-mixed along angular-momentum surfaces within the atmospheric boundary layer no longer holds in cases with substantial eyewall cooling. We then study TC genesis with a small doubly-periodic f-plane. Through cloud-resolving simulations, we show that vertical shear plays an important role on regulating the sensitivity of tropical cyclogenesis to both the environmental rotation and thermodynamic state. As indicated by analogous simulations with the resolution and physics of GCMs, such effects of wind shear might not be fully represented in GCMs. Finally, we investigate convective self-aggregation from non-rotating

  4. Comparative Rotational Dynamics of the Moon, Mercury and Titan

    NASA Astrophysics Data System (ADS)

    Barkin, Yu. V.; Ferrandiz, J. M.

    2006-08-01

    Constant and periodic tidal variations in the gravitational coefficients of second harmonics of gravitational potential of the Moon, Mercury and Titan caused by the attraction of their external bodies are described analytically. On the base of a plane model of translatory-rotary motion of the above-mentioned elastic bodies on elliptical orbits the main variations in the coefficients C[20], C[22], S[22] with periods multiple to the orbit period have been obtained and evaluated. Dynamical effects in resonant rotation of the Moon, Mercury and Titan considered as an unchangeable non-spherical bodies are studied on the basis of two models: firstly, the plane motion on the unperturbed elliptic orbit; secondly, the rotation on the precessing circular orbit. Peale's hydrostatic values of Titan gravitational field parameters C [20], C[22] (Peale, 1973) and two sets of their model values are used in paper to evaluate the unperturbed, forced and resonant effects in the rotation of Titan. For Mercury we use some average equilibrium model of elastic body rotating in resonance 3:2 with orbital motion. Another model of Mercury bases on the modern radio-location data obtained by Peale grope (2004). For the Moon well known dynamical characteristics are used. Obtained Cassini's positional parameters, amplitudes of periodic librations in longitude, periods of resonant librations and others characteristics of studied celestial bodies are given in mutual comparison. On the base of the mechanism of forced relative dynamics of the shells of celestial bodies (Barkin, 2002) due to gravitational attraction of external celestial bodies and evaluated oblateness the high endogenous activity of Titan has been predicted. This fact has obtained the confirmation in data of Cassini-Huygens mission. Especially we study resonant rotation of considered celestial bodies on the base of their models with the liquid core. The fundamental regularities (generalized Cassini's laws) and new effects in their

  5. Particle motion and Penrose processes around rotating regular black hole

    NASA Astrophysics Data System (ADS)

    Abdujabbarov, Ahmadjon

    2016-07-01

    The neutral particle motion around rotating regular black hole that was derived from the Ayón-Beato-García (ABG) black hole solution by the Newman-Janis algorithm in the preceding paper (Toshmatov et al., Phys. Rev. D, 89:104017, 2014) has been studied. The dependencies of the ISCO (innermost stable circular orbits along geodesics) and unstable orbits on the value of the electric charge of the rotating regular black hole have been shown. Energy extraction from the rotating regular black hole through various processes has been examined. We have found expression of the center of mass energy for the colliding neutral particles coming from infinity, based on the BSW (Baňados-Silk-West) mechanism. The electric charge Q of rotating regular black hole decreases the potential of the gravitational field as compared to the Kerr black hole and the particles demonstrate less bound energy at the circular geodesics. This causes an increase of efficiency of the energy extraction through BSW process in the presence of the electric charge Q from rotating regular black hole. Furthermore, we have studied the particle emission due to the BSW effect assuming that two neutral particles collide near the horizon of the rotating regular extremal black hole and produce another two particles. We have shown that efficiency of the energy extraction is less than the value 146.6 % being valid for the Kerr black hole. It has been also demonstrated that the efficiency of the energy extraction from the rotating regular black hole via the Penrose process decreases with the increase of the electric charge Q and is smaller in comparison to 20.7 % which is the value for the extreme Kerr black hole with the specific angular momentum a= M.

  6. Rapidly rotating polytropes in general relativity

    NASA Technical Reports Server (NTRS)

    Cook, Gregory B.; Shapiro, Stuart L.; Teukolsky, Saul A.

    1994-01-01

    We construct an extensive set of equilibrium sequences of rotating polytropes in general relativity. We determine a number of important physical parameters of such stars, including maximum mass and maximum spin rate. The stability of the configurations against quasi-radial perturbations is diagnosed. Two classes of evolutionary sequences of fixed rest mass and entropy are explored: normal sequences which behave very much like Newtonian evolutionary sequences, and supramassive sequences which exist solely because of relativistic effects. Dissipation leading to loss of angular momentum causes a star to evolve in a quasi-stationary fashion along an evolutionary sequence. Supramassive sequences evolve towards eventual catastrophic collapse to a black hole. Prior to collapse, the star must spin up as it loses angular momentum, an effect which may provide an observational precursor to gravitational collapse to a black hole.

  7. Wave-Driven Rotation In Centrifugal Mirrors

    SciTech Connect

    Abraham J. Fetterman and Nathaniel J. Fisch

    2011-03-28

    Centrifugal mirrors use supersonic rotation to provide axial confinement and enhanced stability. Usually the rotation is produced using electrodes, but these electrodes have limited the rotation to the Alfven critical ionization velocity, which is too slow to be useful for fusion. Instead, the rotation could be produced using radio frequency waves. A fixed azimuthal ripple is a simple and efficient wave that could produce rotation by harnessing alpha particle energy. This is an extension of the alpha channeling effect. The alpha particle power and efficiency in a simulated devices is sufficient to produce rotation without external energy input. By eliminating the need for electrodes, this opens new opportunities for centrifugal traps.

  8. Earth rotation: Solved and unsolved problems

    NASA Astrophysics Data System (ADS)

    Cazenave, Anny

    The conference presents papers on reference systems and the observation of the earth's rotation parameters, historical and paleoobservations of the earth's rotation, short term atmospheric and oceanic effects, and mantle and core effects. Attention is given to celestial reference systems, polar motion and signal processing, observations of secular and decade changes in the earth's rotation, and tidal and nontidal acceleration of the earth's rotation. Other topics include high accuracy earth rotation and atmospheric angular momentum, ocean-atmosphere coupling and short term fluctuations of earth rotation, the influence of earthquakes on the polar motion, and the resonance effects of the earth's fluid core.

  9. Convection in the tanks of a rotating spacecraft

    NASA Technical Reports Server (NTRS)

    1972-01-01

    A general study of convection and mixing of a stratified fluid in a rotating container is described, with application to the special problem of fluid heating and convection in a spacecraft tank. The analysis was based on a set of approximate equations for the Navier-Stokes description of fluid convection with small density variations in a rotating system, including effects of body forces due to temperature stratification (caused by a heater) and arbitrary time-dependent rotation of the tank about a noncentral axis. An efficient numerical finite difference scheme and computational method are described for the convection of vorticity and energy in a two-dimensional tank. Special procedures were developed for analysis of the thermodynamic states resulting from the approximate flow equations derived for small density variations. Results of the numerical simulation are presented for studying the effectiveness of rotation maneuvers in mixing stratified oxygen in the tanks of an Apollo spacecraft. Significant effects of the rotation maneuvers are discussed, including the reduction of the potential for pressure collapse.

  10. Clockwise block rotations in the Perija Mountains, Venezuela

    SciTech Connect

    Gose, W.A. ); Perarnau, A. ); Castillo, J. )

    1993-02-01

    Paleomagnetic analyses of Mesozoic sedimentary rocks (8 sites, 115 samples) from the Perija Mountains, Venezuela, yield well-grouped directions of both polarities. Fold tests imply that the magnetization of the Jurassic La Quinta Formation is pre-mid-Cretaceous in age and that the Lower Cretaceous Cogollo Group acquired its magnetization prior to its mid-Tertiary deformation. These data as well as the results from the Cretaceous Apon and La Luna Formations yield consistent northeast or southwest declinations and inclinations corresponding to the present latitude of the sampling area. The clockwise rotations indicated by these data are interpreted to be the result of rotation of fault-bounded blocks in a left-lateral strike-slip zone. Faults such as the Cogollo, La Ge, and Totumo faults which intersect the Perija-Tigre fault at low angles, had initially a north-northwest strike. The Late Oligocene northwest-southeast compression which initiated the uplift of the Perija Mountains rotated these faults to their present north-northeast orientation imparting the observed left-lateral slip. Our paleomagnetic data measure the corresponding rotation of the fault-bounded blocks. Model calculations suggest that a displacement on these faults of less than ten kilometers would be sufficient to cause the observed approximately 45[degrees] clockwise rotations.

  11. On-line phase measuring profilometry for a rotating object

    NASA Astrophysics Data System (ADS)

    Wang, Peng; Cao, Yiping; Yang, Xin; Peng, Kuang

    2014-11-01

    On-line phase measuring profilometry (OPMP) for a rotating object is proposed. N frames of circular sinusoidal grating patterns are designed in advance, in which the transmittance along the radial direction is sinusoidal and there is a fixed shifting phase pitch of 2π/N between every adjacent two grating patterns along the radial direction. While the measured object is rotating, the designed grating patterns are projected onto the rotating object by digital light processing and the corresponding deformed patterns caused by the object at different positions are captured by a charge coupled device camera. By pixel matching and rotation transformation with special marks, N frames of the deformed patterns of the object at the same position can be extracted. Hence, the rotating object can be reconstructed by the extracted deformed patterns. The results of computer emulation and experiment show the feasibility and validity of the proposed OPMP. Either the maximum measurement absolute error is 0.118 mm or the maximum root mean square error is 0.077 mm in the measured region of 0 to 25 mm.

  12. Conversion of rotational output to linear force-a transmission

    SciTech Connect

    Montalbano, P.J.

    1991-08-27

    This patent describes a transmission device for converting rotational torque into linear force. It comprises a combination large internally toothed annular gear and large flywheel rotatable within a housing by bearing means, in operative interconnection with a small externally toothed circular gear mounted within it annulus and provided with a source of variable rotary motion for driving the annular gear, a second large internally toothed annular gear, located above the first the annular gear, rotatable within a housing by bearing means and provided with a clutch connection to first annular gear, is in operative connection with three small externally toothed circular gears driven by the second annular gear, a member pivotably supported along the axis of the annular gear and rockable on the axis, the member having an upper and a lower arm, the upper arm in interconnection with two of the respective gears and the lower arm in interconnection with one of the respective gears, the gears driven by the second annular gear, in upper arm the gears causing the rocker element to move two off- centered weights, the first weight rotatable with one of the gears, the second weight rotatable in the opposite direction and mounted within the rocker element driven by an additional small externally toothed circular gear in mesh with one of the small gears, the weights generating centrifugal forces.

  13. Rotational viscometer for high-pressure high-temperature fluids

    DOEpatents

    Carr, Kenneth R.

    1985-01-01

    The invention is a novel rotational viscometer which is well adapted for use with fluids at high temperatures and/or pressures. In one embodiment, the viscometer includes a substantially non-magnetic tube having a closed end and having an open end in communication with a fluid whose viscosity is to be determined. An annular drive magnet is mounted for rotation about the tube. The tube encompasses and supports a rotatable shaft assembly which carries a rotor, or bob, for insertion in the fluid. Affixed to the shaft are (a) a second magnet which is magnetically coupled to the drive magnet and (b) a third magnet. In a typical operation, the drive magnet is rotated to turn the shaft assembly while the shaft rotor is immersed in the fluid. The viscous drag on the rotor causes the shaft assembly to lag the rotation of the drive magnet by an amount which is a function of the amount of viscous drag. A first magnetic pickup generates a waveform whose phase is a function of the angular position of the drive magnet. A second magnetic pickup generates a waveform whose phase is a function of the angular position of the third magnet. An output is generated indicative of the phase difference between the two waveforms.

  14. Rotational viscometer for high-pressure, high-temperature fluids

    DOEpatents

    Carr, K.R.

    1983-06-06

    The invention is a novel rotational viscometer which is well adapted for use with fluids at high temperatures and/or pressures. In one embodiment, the viscometer include a substantially non-magnetic tube having a closed end and having an open end in communication with a fluid whose viscosity is to be determined. An annular drive magnet is mounted for rotation about the tube. The tube encompasses and supports a rotatable shaft assembly which carries a rotor, or bob, for insertion in the fluid. Affixed to the shaft are (a) a second magnet which is magnetically coupled to the drive magnet and (b) a third magnet. In a typical operation, the drive magnet is rotated to turn the shaft assembly while the shaft rotor is immersed in the fluid. The viscous drag on the rotor causes the shaft assembly to lag the rotation of the drive magnet by an amount which is a function of the amount of viscous drag. A first magnetic pickup generates a waveform whose phase is a function of the angular position of the drive magnet. A second magnetic pickup generates a waveform whose phase is a function of the angular position of the third magnet. Means are provided to generate an output indicative of the phase difference between the two waveforms. The viscometer is comparatively simple, inexpensive, rugged, and does not require shaft seals.

  15. JET ROTATION DRIVEN BY MAGNETOHYDRODYNAMIC SHOCKS IN HELICAL MAGNETIC FIELDS

    SciTech Connect

    Fendt, Christian

    2011-08-10

    In this paper, we present a detailed numerical investigation of the hypothesis that a rotation of astrophysical jets can be caused by magnetohydrodynamic (MHD) shocks in a helical magnetic field. Shock compression of the helical magnetic field results in a toroidal Lorentz force component that will accelerate the jet material in the toroidal direction. This process transforms magnetic angular momentum (magnetic stress) carried along the jet into kinetic angular momentum (rotation). The mechanism proposed here only works in a helical magnetic field configuration. We demonstrate the feasibility of this mechanism by axisymmetric MHD simulations in 1.5 and 2.5 dimensions using the PLUTO code. In our setup, the jet is injected into the ambient gas with zero kinetic angular momentum (no rotation). We apply different dynamical parameters for jet propagation such as the jet internal Alfven Mach number and fast magnetosonic Mach number, the density contrast of the jet to the ambient medium, and the external sonic Mach number of the jet. The mechanism we suggest should work for a variety of jet applications, e.g., protostellar or extragalactic jets, and internal jet shocks (jet knots) or external shocks between the jet and the ambient gas (entrainment). For typical parameter values for protostellar jets, the numerically derived rotation feature looks consistent with the observations, i.e., rotational velocities of 0.1%-1% of the jet bulk velocity.

  16. Piezoelectric Vibration Damping Study for Rotating Composite Fan Blades

    NASA Technical Reports Server (NTRS)

    Min, James B.; Duffy, Kirsten P.; Choi, Benjamin B.; Provenza, Andrew J.; Kray, Nicholas

    2012-01-01

    Resonant vibrations of aircraft engine blades cause blade fatigue problems in engines, which can lead to thicker and aerodynamically lower performing blade designs, increasing engine weight, fuel burn, and maintenance costs. In order to mitigate undesirable blade vibration levels, active piezoelectric vibration control has been investigated, potentially enabling thinner blade designs for higher performing blades and minimizing blade fatigue problems. While the piezoelectric damping idea has been investigated by other researchers over the years, very little study has been done including rotational effects. The present study attempts to fill this void. The particular objectives of this study were: (a) to develop and analyze a multiphysics piezoelectric finite element composite blade model for harmonic forced vibration response analysis coupled with a tuned RLC circuit for rotating engine blade conditions, (b) to validate a numerical model with experimental test data, and (c) to achieve a cost-effective numerical modeling capability which enables simulation of rotating blades within the NASA Glenn Research Center (GRC) Dynamic Spin Rig Facility. A numerical and experimental study for rotating piezoelectric composite subscale fan blades was performed. It was also proved that the proposed numerical method is feasible and effective when applied to the rotating blade base excitation model. The experimental test and multiphysics finite element modeling technique described in this paper show that piezoelectric vibration damping can significantly reduce vibrations of aircraft engine composite fan blades.

  17. Radial velocity planet detection biases at the stellar rotational period

    NASA Astrophysics Data System (ADS)

    Vanderburg, Andrew; Plavchan, Peter; Johnson, John Asher; Ciardi, David R.; Swift, Jonathan; Kane, Stephen R.

    2016-07-01

    Future generations of precise radial velocity (RV) surveys aim to achieve sensitivity sufficient to detect Earth mass planets orbiting in their stars' habitable zones. A major obstacle to this goal is astrophysical RV noise caused by active areas moving across the stellar limb as a star rotates. In this paper, we quantify how stellar activity impacts exoplanet detection with radial velocities as a function of orbital and stellar rotational periods. We perform data-driven simulations of how stellar rotation affects planet detectability and compile and present relations for the typical time-scale and amplitude of stellar RV noise as a function of stellar mass. We show that the characteristic time-scales of quasi-periodic RV jitter from stellar rotational modulations coincides with the orbital period of habitable-zone exoplanets around early M-dwarfs. These coincident periods underscore the importance of monitoring the targets of RV habitable-zone planet surveys through simultaneous photometric measurements for determining rotation periods and activity signals, and mitigating activity signals using spectroscopic indicators and/or RV measurements at different wavelengths.

  18. Reduction of Sample Rotation in Electrostatic Levitation

    NASA Technical Reports Server (NTRS)

    Hyers, R. W; Johnson, W. L.; Savage, L.; Rogers, J. R.

    2000-01-01

    In many containerless processing systems, control of sample rotation is an important issue. Sample rotation is even more important for microgravity containerless processing systems, where the centrifugal acceleration can approach 1 g for even a small rotation rate. Prior work on rotation control by Rhim focused on driving the sample rotation at a controlled rate for droplet dynamics experiments and measurement of electrical conductivity. His technique allows controlled, fast rotation, but for many microgravity experiments the goal is zero rotation. To minimize sample rotation, two approaches are apparent: first, to identify and balance or eliminate the driving forces for undesired sample rotation, or second, implement a feedback-based rotation control loop in parallel with the position control loop. In this work, we have taken the first approach. To minimize sample rotation, the simplest approach is to identify and balance or eliminate the driving forces for undesired sample rotation. Our experiments show that the dominant driving force for rotation of machined Zr spheres in the MSFC ESL is photon pressure from the heating laser. Experimental results showing the correlation between heating power and torque are compared to theoretical predictions, and a strategy for minimizing the torque due to photon pressure is presented.

  19. Inverse relationship between heat stable enterotoxin-b induced fluid accumulation and adherence of F4ac-positive enterotoxigenic Escherichia coli in ligated jejunal loops of F4ab/ac fimbria receptor-positive swine.

    PubMed

    Erume, Joseph; Wijemanne, Prageeth; Berberov, Emil M; Kachman, Stephen D; Oestmann, Daniel J; Francis, David H; Moxley, Rodney A

    2013-01-25

    Heat-labile enterotoxin (LT) produced by enterotoxigenic Escherichia coli (ETEC) increases bacterial adherence to porcine enterocytes in vitro and enhances small intestinal colonization in swine. Heat-stable enterotoxin-b (STb) is not known to affect colonization; however, through an induction of net fluid accumulation it might reduce bacterial adherence. The relationship between fluid accumulation and bacterial adherence in jejunal loops inoculated with ETEC strains that produce LT, STb, both, or neither toxin was studied. Ligated jejunal loops were constructed in weaned Yorkshire pigs in two independent experiments (Exp. 1, n=5, 8-week-old; Exp. 2, n=6, 6-8-week-old). Each pig was inoculated with six F4ac(+)E. coli strains: (1) LT(+), STb(+) parent (WAM2317); (2) STb(-) (ΔestB) mutant (MUN297); (3) MUN297 complemented with STb (MUN298); (4) LT(-) STb(-) (ΔeltAB ΔestB) mutant (MUN300); (5) MUN300 complemented with LT (MUN301); and (6) 1836-2 (non-enterotoxigenic, wild-type). Pigs were confirmed to be K88 (F4)ab/ac receptor-positive in Exp. 2 by testing for intestinal mucin-type glycoproteins and inferred to be receptor-positive in both Exp. 1 and 2 based on histopathologic evidence of bacterial adherence. Strains that produced STb induced marked fluid accumulation with the response (ml/cm) to WAM2317 and MUN298 significantly greater than that to the other strains (P<0.0001). Conversely, bacterial adherence scores based on immunohistochemistry and CFU/g of washed mucosa were both lowest in the strains that expressed STb and highest in those that did not. For the two experiments combined, the Pearson correlation coefficient (R) between fluid volume (ml/cm) and log CFU per gram was -0.57021 (P<0.0001); R(2)=0.3521 (n=197). These results support the hypothesis that enterotoxin-induced fluid accumulation flushes progeny organisms into the lumen of the bowel, thereby increasing the likelihood of fecal shedding and transmission of the pathogen to new hosts. PMID

  20. Earth Rotation Parameters from DSN VLBI: 1994

    NASA Technical Reports Server (NTRS)

    Steppe, J. A.; Oliveau, S. H.; Sovers, O. J.

    1994-01-01

    In this report, Earth Rotation Parameter (ERP) estimates ahve been obtained from an analysis of Deep Space Network (DSN) VLBI data that directly aligns its celestial and terrestrial reference frames with those of the International Earth Rotation Service (IERS).