Mass housing

Professor Vir Handa's abiding interest in low‐cost housing for the lower‐income earners is demonstrated in his paper from the University of Waterloo, Ontario. He draws experience from time spent at the Building Research Institute, Roorkee, under the United Nations TOKTEN Programme and illustrates his paper with pictures from Trinidad, where he is an External Examiner at the University of the West Indies. He argues that although shelter communities are being built without any government help and without any awareness of any codes and standards, the job of the expert should be to determine new affordable code requirements.     

Abscopal Effect of Frozen Autograft Reconstruction Combined with an Immune Checkpoint Inhibitor Analyzed Using a Metastatic Bone Tumor Model

We evaluated the abscopal effect of re-implantation of liquid nitrogen-treated tumor-bearing bone grafts and the synergistic effect of anti-PD-1 (programmed death-1) therapy using a bone metastasis model, created by injecting MMT-060562 cells into the bilateral tibiae of 6–8-week-old female C3H mice. After 2 weeks, the lateral tumors were treated by excision, cryotreatment using liquid nitrogen, excision with anti-PD-1 treatment, and cryotreatment with anti-PD-1 treatment. Anti-mouse PD-1 4H2 was injected on days 1, 6, 12, and 18 post-treatment. The mice were euthanized after 3 weeks; the abscopal effect was evaluated by focusing on growth inhibition of the abscopal tumor. The re-implantation of frozen autografts significantly inhibited the growth of the remaining abscopal tumors. However, a more potent abscopal effect was observed in the anti-PD-1 antibody group. The number of CD8+ T cells infiltrating the abscopal tumor and tumor-specific interferon-γ (IFN-γ)-producing spleen cells increased in the liquid nitrogen-treated group compared with those in the excision group, with no significant difference. The number was significantly higher in the anti-PD-1 antibody-treated group than in the non-treated group. Overall, re-implantation of tumor-bearing frozen autograft has an abscopal effect on abscopal tumor growth, although re-implantation of liquid nitrogen-treated bone grafts did not induce a strong T-cell response or tumor-suppressive effect.     

Tensile, Solubility, and Electrophoretic Properties of Egg White Films as Affected by Surface Sulfhydryl Groups

Films plasticized with polyethylene glycol were cast from alkaline (pH 10.5, 11.0, or 11.5), aqueous egg white (EW) solutions with or without heating (40°C for 30 min). Prior to casting, concentration of surface sulfhydryl (SH) groups was determined and they increased (P < 0.05) (3.81–19.45 μM/g protein) with both pH and heating, presumably due to protein denaturation and cleavage of disulfide (S-S) bonds. Concentration of surface SH groups correlated (P < 0.05) with film tensile strength (r = 0.70), elongation at break (r = 0.86), and film total soluble matter (r =−0.94). Most likely, surface SH groups formed S-S bonds through air oxidation and/or sulfhydryl/disulfide interchange, thus contributing to EW film formation. SDS-PAGE patterns in presence or absence of 2-mercaptoethanol confirmed occurrence of S-S bonding in dried EW films.     

Al2O3f+Cf/ZL109混杂复合材料钻削加工性的研究

利用挤压铸造法制备了Al₂O_3f+C_f/ZL109短纤维混杂金属基复合材料,并进行了钻削加工试验研究。考察了Al₂O₃短纤维和C短纤维含量、纤维位向、钻削速度及进给量对钻削力、刀具磨损和钻削精度的影响,并进行了分析。结果表明:以刀具磨损作为衡量标准,该混杂复合材料的钻削加工性次于基体合金。      

Linear Scheduling Using Optimal Control Theory

Construction planning and control literature reveal much effort in the recent past in the development of managerial control systems involving classical optimization techniques such as simulation, queuing theory, linear, dynamic programming, etc. Construction managers typically reach decisions in a perspective of time and in light of temporal criteria. The aforementioned techniques deal with the theoretical and computational aspects of time by static methods: Effects of one or more actions in a given interval are aggregated over time. Optimal Control Theory, a new branch of optimization, makes it possible to view the construction‐production process as a dynamic system that evolves over time. This paper presents a Continuous Optimal Control formulation of a hypothetical cut‐and‐fill job on a section of a highway. It is shown that Discrete Optimal Control framework is adequate for construction. The problem of scheduling the construction of a bridge due to Selinger is solved using this approach.     

Gibbs free energies of formation of molybdenum carbide and tungsten carbide from 1173 to 1573 K

The gas equilibrium method of CH₄/H₂ has been widely used for measuring carbon potential. However, it has been reported that this method is not applicable at high temperatures since the equilibrium between CH₄ and H₂ is disturbed by the reaction of CH₄ with moisture in the system. Nevertheless, this method should be applicable theoretically at high temperatures below which CH₄ decomposition can be neglected because the equilibrium between CH₄ and H₂ reaches constant ratio in spite of the reaction. Since the role of moisture is to oxidize the sample during the measurements under the oxygen potential determined byPh ₂ o/ph ₂ ratio, the Gibbs free energies of formation of Mo₂C and WC were successfully measured from 1173 to 1573 K by keeping the moisture level in the system low enough not to oxidize the sample. The experimental results are expressed by the following equations which were derived by least squares treatments of the data: Mo₂C:ΔG = -68270 + 8.23T J mol^-1 WC:ΔG = -52330 + 14.06T J mol^-1 These values were in good agreement with those measured by M. Gleiseret al. for narrow tempareture ranges using the CO/CO₂ gas equilibrium method.     

A multichannel FES system for the restoration of motor functions inhigh spinal cord injury patients: a respiration-controlled system formultijoint upper extremity

A multichannel functional electrical stimulation (FES) system for the restoration of quadriplegic upper extremity function is described. The system is composed of a personal computer NEC PC-8801mkII, peripheral electronic circuits, CRT display and respiratory sensors for volitional control by the patient, and percutaneous electrodes. A C4 quadriplegic patient could drink canned tea by herself by using this FES system. Distinct features of the system are as follows: 1) Versatile volitional control was realized by controlling the memory allocation of the stored stimulation data by voluntary respiratory signals. 2) Sophisticated fine control of the fingers, wrists, and elbow was realized by creating the multichannel stimulation data from recorded myoelectric activities of normal subjects during movements of the upper limb.