Utilization of habrobracon and artemia as experimental materials in bioastronautic studies status report, jan. - jun. 1965

Radiation and gravitational effect on wasps and shrimp - animal stud

The utilization of Habrobracon and artemia as experimental materials in bioastronautic studies

In the reproductive performance of female braconids striking contrasts were revealed between the results from the actual biosatellite flight and those from experiments when the recovered vehicle was subjected to the forces of simulated launching and recovery. Second week decreases in egg production due to the radiation damage of cells in mitosis were minimized for the females irradiated during space flight. It was demonstrated that females irradiated for two days during orbital flight laid as many eggs during the second week as the unirradiated ground-based controls. After the 10th day their oviposition records exceeded control values. The hatchability of eggs deposited by Biosatellite II females was excellent. Explanations were sought for the space flight's cancellation of the characteristic radiation-induced decrease in egg production, and for the exceptionally good hatchability of eggs derived from most of the cell types in the irradiated ovarioles. Eggs from only two classes of cells showed enhanced embryonic lethality: those poised in meiotic metaphase during their mother's orbital flight, and those from oocytes beginning vitellogenesis

A Greedy Hypercube-Labeling Algorithm

Due to its attractive topological properties, the hypercube multiprocessor has emerged as one of the architectures of choice when it comes to implementing a large number of computational problems. In many such applications, Gray-code labelings of the hypercube are a crucial prerequisite for obtaining efficient algorithms. We propose a greedy algorithm that, given an n-dimensional hypercube H with N=22 nodes, returns a Gray-code labeling of H, that is, a labeling of the nodes with binary strings of length n such that two nodes are neighbors in the hypercube if, and only if, their labels differ in exactly one bit. Our algorithm is conceptually very simple and runs in O(N log N) time being, therefore, optimal. As it turns out, with a few modifications our labeling algorithm can be used to recognize hypercubes as well

Anchored Bulkhead Failure on the Arabian Gulf

A 1500-m long anchored bulkhead with a height of 20m exhibited a localized failure in the form of broken and overstressed anchors several months after construction. The wall had not yet been subjected to its full design loadings. The soil conditions in the failure area differ from those occurring along the rest of the quay wall by the presence of a very soft silt/clay layer, and during construction the wall had been strengthened in this area. Post-failure analysis of the anchored bulkhead indicated that the primary cause of the failure was overly optimistic design assumptions for the strength of the silt/clay layer and mobilization of passive pressure. The effects of certain construction methods employed and the settlement of the silt/clay were contributing factors in the failure. A relieving platform constructed one year after the failure was designed for the original undrained strength of the silt/clay, without taking into account the effects of soil consolidation and strength gains which had occurred

Net Energy of Finishing Diets Containing Light or Normal Test Weight Corn

Net energy (NE) of diets containing 77.7% whole corn of either normal (53.8 Ib/bushel, NC) or light (40.8 Ib/bushel, LC) test weight was determined by total collection and indirect respiration calorimetry using six crossbred steers (avg wt 327 kg). Diet treatments were applied in a switchback design. The steers were initially adapted to ad libitum intake of either NC or LC diets for 32 days followed by 7 days total feces and urine collection. Gaseous exchange was subsequently measured for at least 48 hours. Intake was then reduced to an estimated 1.1 times maintenance for 6 days and collections were repeated. The steers were then switched between NC and LC diets and the entire process was repeated. As a percentage of gross energy consumed, fecal energy losses were 32% greater for the NC diet compared to LC (P\u3c .01). Urinary energy losses were unaffected by diet (P \u3e .20). Although energy lost as methane did not differ between diets at high intake, it was 27% greater for LC than NC at low intake (interaction P.20). Partial efficiencies of ME used for maintenance (k,) and gain (k,), as well as ME required for maintenance, also were not different (P\u3e.20). Diet NE for maintenance and gain was 13% greater for LC than NC. NE estimates calculated by difference for light and normal whole corn were 2.48, 1.65, 2.15 and 1.43 mcal/kg dry matter, respectively. These data demonstrate that corn of low test weight is not inherently lower in NE content than normal corn

Applicability of Competency-Based Assessment for TVET Interns: Comparing Between Indonesia and Laos

This study is an international research collaboration of RAVTE (The Regional Association for Vocational Teacher Education in East and Southeast Asia) members which analyses the assessment of students’ internship using Competency-Based Assessment (CBA) approach. This study analyses the application of CBA for  internship assessment using four relevant CBA subcategories: 1) Standards, 2) Planning, 3) Methods, 4) Evidence and, Judgment. The study aims to take a portrait of CBA application in selected three universities, two in  Indonesia and one in Laos. The research used a descriptive quantitative approach which conducted among 85 samples. The results give an understanding on the suitability of CBA implementation in each country and to identify potential obstacles. The study revealed that respondents from both countries were quite successful in using evidence and judgement for CBA. However, there were differences in the performance of internships assessment. Most respondents at the two universities use the CBA standards for their internships programs. While the Indonesian samples are successful at applying CBA principles of planning (89.39%), the surveyed respondents from Laos still seemed to have more difficulties in this area (61,2%). While the Indonesian universities rated good in using methods to assess the application in the internship industry (78%), it was found that the methods used for assessing students’ internship at the university in Laos was less satisfying (35.5%). Some issues identified includes unclear guidance of competencies identification unit, lack of mechanism for coordination between quality assurance institutions, and a very limited access for industry collaboration and participation in the assessment planning, standard, method, and judgment

Path integral solution for an angle-dependent anharmonic oscillator

We have given a straightforward method to solve the problem of noncentral anharmonic oscillator in three dimensions. The relative propagator is presented by means of path integrals in spherical coordinates. By making an adequate change of time we were able to separate the angular motion from the radial one. The relative propagator is then exactly calculated. The energy spectrum and the corresponding wave functions are obtained.Comment: Corrected typos and mistakes, To appear in Communications in Theoretical Physic