Constraint checking during error recovery

The system-level software onboard a spacecraft is responsible for recovery from communication, power, thermal, and computer-health anomalies that may occur. The recovery must occur without disrupting any critical scientific or engineering activity that is executing at the time of the error. Thus, the error-recovery software may have to execute concurrently with the ongoing acquisition of scientific data or with spacecraft maneuvers. This work provides a technique by which the rules that constrain the concurrent execution of these processes can be modeled in a graph. An algorithm is described that uses this model to validate that the constraints hold for all concurrent executions of the error-recovery software with the software that controls the science and engineering activities of the spacecraft. The results are applicable to a variety of control systems with critical constraints on the timing and ordering of the events they control

Inductive and Electrostatic Acceleration in Relativistic Jet-Plasma Interactions

We report on the observation of rapid particle acceleration in numerical simulations of relativistic jet-plasma interactions and discuss the underlying mechanisms. The dynamics of a charge-neutral, narrow, electron-positron jet propagating through an unmagnetized electron-ion plasma was investigated using a three-dimensional, electromagnetic, particle-in-cell computer code. The interaction excited magnetic filamentation as well as electrostatic plasma instabilities. In some cases, the longitudinal electric fields generated inductively and electrostatically reached the cold plasma wave-breaking limit, and the longitudinal momentum of about half the positrons increased by 50% with a maximum gain exceeding a factor of 2 during the simulation period. Particle acceleration via these mechanisms occurred when the criteria for Weibel instability were satisfied.Comment: Revised for Phys. Rev. Lett. Please see publised version for best graphic

The inherent danger in laser safety eyewear

I have designed an experiment which explained why the filter in a laser protective eyewear could crack under prolonged contact to a laser beam. My hypothesis stated that the nonlinearity of absorption of light played an important role in the failure of the filter. Using a xeon-arc lamp, a photoconductive cell, a multimeter and filters that consisted of 0 to 15 blue transparency(ies), I indirectly measured the amount of light that these filter absorbed. From the data I affirmed my hypothesis. If a laser beam hit an actual protective filter, because of the nonlinearity of absorption, the front surfaces of the filters would absorb much more laser light than the back surfaces. thus the front would heat up and expand more quickly than the back causing the filter to crack. Because future optometrists will need to learn the practical significance of the nonlinear process of absorption, I have also incorporated my experimental procedure into a physical optics experiment

An assessment of supervisory well-being in a statewide guardian ad litem program

Guardian ad Litem programs recruit, train, and supervise volunteers who are court-appointed to represent and advocate for the best interests of children in family court proceedings involving allegations of abuse or neglect. This manuscript presents the results of an assessment of supervisory well-being. We assessed 81 supervisors on four measures of well-being and presented a staff development workshop to discuss the findings. The assessment found that Guardian ad Litem supervisors had less social support, lower self-esteem, stronger caregiving identities, and more distress than a comparison group of social workers. We discuss the salience of leadership and supervisory support in promoting employee well-being

Perbandingan hasil tangkapan tuna hand line dengan teknik pengoperasian yang berbeda di Laut Maluku

Pancing ulur tuna telah digunakan secara luas oleh nelayan di Laut Sulawesi dan sekitarnya untuk menangkap ikan pelagis besar dengan kapal-kapal ukuran kecil. Walaupun konstruksinya telah berkembang sejak lama, tetapi masih memiliki potensi untuk meningkatkan efisiensi penangkapan dan selektivitasnya. Keberhasilan penangkapan tuna hand line, di samping dipengaruhi oleh umpan, juga dipengaruhi oleh teknik pengoperasian. Oleh karena itu, penelitian ini bertujuan untuk mempelajari hasil tangkapan tuna hand line dengan teknik pengoperasian yang berbeda di perairan Maluku. Penelitian ini dilakukan pada bulan September-November 2014 dengan menggunakan KM. Coelacanth dan KM. Melati 27, masing-masing sebanyak 6 trim. Dua teknik pengoperasian tuna hand line yang berbeda adalah 1. umpan alami pemberat batu dan tinta cumi (KM. Coelacanth), 2. umpan alami dengan kantong hambur (KM Melati 27). Hasil tangkapan KM. Coelacanth sebanyak 111 ekor madidihang (Thunnus albacares), 28 ekor tuna mata besar (Thunnus obesus), 14 ekor marlin (Makaira sp.), dan 8 ekor layaran (Istiophorus sp). Hasil tangkapan KM. Melati 27: 101 ekor madidihang dan 9 ekor tuna mata besar. Hasil analisis uji t terhadap jumlah tangkapan menunjukkan bahwa penggunaan umpan alami berpemberat batu dan tinta cumi tidak berbeda nyata dengan hasil tangkapan menggunakan umpan alami kantong hambur

Extreme hyperkalaemia secondary to malignant ureteric obstruction: Case Report

We report a case of a 42 year old patient who collapsed at an airport departure lounge. The patient was investigated and found to have advanced renal failure with serum potassium (K+) of 10.3 mmol/L, creatinine of 3581 µmol/L and urea of 59.9 mmol/L secondary to obstructive uropathy due to advanced bladder cancer. Although these biochemical changes were thought to be incompatible with life, he made a slow recovery following haemodialysis and insertion of bilateral percutaneous nephrostomy tubes. The East African Medical Journal Vol. 83 (11) 2006: pp. 637-64

Early Arterial Intimal Thickening and Plaque Is Related with Treatment Regime and Cardiovascular Disease Risk Factors in Young Adults Following Childhood Hematopoietic Stem Cell Transplantation

The long-term vascular effects following childhood hematopoietic stem cell transplantation (HSCT) are not well characterized. We compared arterial wall morphology and function using very-high resolution ultrasound (25–55 MHz) in 62 patients following autologous (n = 19) or allogenic (n = 43) HSCT for childhood malignancies and hematological disease (median age 25.9 years, IQR 21.1–30.1; median follow-up time 17.5 years IQR 14.1–23.0) with an age matched healthy control group (n = 44). Intima-media thickness of carotid (CIMT 0.49 ± 0.11 vs. 0.42 ± 0.06 mm, p 0.06 mm) of femoral or radial arteries (n = 17) and subclinical carotid or femoral plaques (n = 18) were more common (p 30 kg/m2, hsCRP >2.5 mg/L, hypertension, HbA1c > 42 mmol/L, and cumulative anthracycline >150 mg/m2. Cumulative metabolic syndrome criteria and cardiovascular disease (CVD) risk factors were more common among HSCT and related with CIMT (p < 0.001), but CIMT was similar among controls and HSCT without CVD risk factors. Long-term childhood HSCT survivors show early arterial aging related with radiation, metabolic, and CVD risk factors. Prevention of risk factors could potentially decelerate early arterial wall thickening

Rumination, Brooding, and Reflection: Prospective Associations with Suicide Ideation and Suicide Attempts

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151274/1/sltb12507_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151274/2/sltb12507.pd