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Proteins are the essential components of all living creatures that link genes and biofunctionalities, and their crystallizations have attracted much interest; the study of the 3D structures through X-ray crystallography would provide critical information for novel drug design and disease treatment. To reduce searching efforts, to minimize the amount of protein solutions, and to increase the final accuracy, here we demonstrate protein crystallization optimization using the in-house fabricated hydrogel-digitized microfluidic system (HD-MFS). This technique is incorporated with a two-stage feedback-system-control (2s-FSC) algorithm for the fast and easy screening of chemical conditions required for obtaining high quality and large protein crystals. We have demonstrated the efficacy of our technique by crystallizing three different types of proteins, including lysozyme, proteinase-K, and KDM-4A. Large and high quality protein crystals could be obtained by conducting many fewer crystallization trials (tens experiments) in parallel from a pool of thousands of possible trials; thus, our methodology allows for thorough screening of crystallization conditions without the need for elaborate and expensive robotic solutions. In addition, the expanded two-stage approach for the feedback-system-control algorithm (FSC) can not only rapidly identify the possible locations in a vast parameter space but also refine the final searching results in a more confined and accurate region, where the desired chemical conditions can be identified quickly and accurately to obtain large and top quality protein crystals. The performance comparison with other published literature has been carried out, and the results indicate that the current design can perform protein crystallization more efficiently by the integration of the HD-MFS and FSC algorithm. We strongly believe that the hydrogel-digitized microfluidic system with the 2s-FSC algorithm could be one of the easiest ways to obtain protein crystals of unsolved novel protein macromolecules.

Chinese leymus (Leymus chinensisTrin.) is a perennial grass of the Gramineae, which is widely distributed in China, Mongolia and in Russian-Siberian. In order to explore the potential of biotechnology for genetic improvement of this forage grass, an efficient tissue culture system was established and the factors affecting plant regeneration were evaluated. Immature inflorescence segments 3–5 mm in length from eight accessions were cultured on N6 medium supplemented with 2.26–22.60 µM 2,4-D. The callus induction frequency ranged from 72.11 to 82.19%. Shoots were differentiated from the calli on N6 medium containing 4.65 µM kinetin and 4.44 µM BA. Viable regenerants were developed on hormone-free medium. Normal plants were obtained after natural vernalization in the field. The plant regeneration frequency in Chinese leymus was associated with different genotypes and different combinations of growth regulators in medium. The concentration of 2,4-D in the callus induction medium had a strong effect on successive plant regeneration. Relatively higher concentrations of 2,4-D (i.e., 9.04 and 22.60 µM) were more favorable to the plant regeneration than lower ones (i.e., 2.26 and 4.52 µM). This is the first report on plant regeneration in vitroin L. chinensis.

Abstract. As an extension of the Evolutionary Structural Optimization [ESO] method, the bidirectional ESO [BESO] method has effectively addressed various topology optimization problems. It is observed in ESO/BESO applications that the optimal solution obtained strongly depends on the finite element mesh. This paper presents an improved BESO methodology incorporating a means of controlling the optimization process in order to satisfy a constraint on structural perimeter and thus to solve this size effect problem. Numerical tests are conducted on three examples at different levels of finite element discretization. Solutions convergent with respect to the grid refinement are obtained, especially when the perimeter bound is sufficiently low. Simpler topologies consisting of fewer and larger structural members and holes are generated when a more restricting constraint is imposed. Therefore, it is concluded that BESO combined with perimeter control is capable of suppressing mesh dependency and controlling the structural complexity for topology optimization problems.

AbstractMonte Carlo studies on the domains and mesoscopic structures of Pb(Mg1/3NB2/3)O3(PMN) are carried out using an electrostatic model with varying Coulomb interacting radius, RC. It is revealed that various ordered structures, including 1/2{111}. 1/3{111}, 1/2{100}, as well as other rather subtle mesoscopic structures could be obtained by varying the Coulomb interacting radius. Interestingly, for 1/2{111} ordered structure, antiphase boundaries could exist (e.g., for RC= 3a, where ais the lattice constant). These, along with the rather disordered mesoscopic structures forming for other RC, e.g., RC= 2a, may provide a reasonable explanation of the experimental observation results on mesoscopic structures of PMN.

AbstractMonte Carlo simulations have been carried out to clarify the controversy about the atomic nature of the 1/2{111} ordered domains by using an electrostatic model with varying Coulomb interacting radius. It is revealed that, while the ordered domains is in agreement with the random-layer model, it ispossible for the existence of 2∼5nm space-charged clusters embedded in the random-layer matrix when the ordered domains are large enough. This could explain the existing experimental results on the ordered structure of La-doped and undoped PMN.

Abstract.: An effective optimization procedure for finding structural shapes and topologies that minimize structural compliance and weight subject to stress and deflection constraints is presented. This new approach, called “Metamorphic Development” (MD), can allow a structure to grow and degenerate towards an optimum topological layout. In this method, the optimization can start from the simplest possible geometry (layout) or any degree of development of the structure rather than from a complex ground mesh. The structure is then developed metamorphically using rectangular and triangular elements that can be of any specified sizes. Examples demonstrate the potential of the MD optimization procedure to generate innovative solutions to structural design problems. Results are given and the growth and degeneration histories during optimization are illustrated.

The relaxation process of C60molecule around glass transition temperature is studied by Monte Carlo simulation, using a new model of the energy barrier of molecule between two orientational states in C60crystal, which depends on the state of neighboring molecules. The results show that the relaxation is slightly non-exponential, which can be fit to Kohlrausch–Williams–Watts (KWW) function. The non-exponential factor βis 0.962±0.002, and this value reproduces the experimental data that has not been explained before.

A novel multi-parameter overall situation optimisation method has been developed for use on antenna reflector structures. Various structural performances arc included as objective functions. The design variables involve geometric and size variables of structures. Various working environments and loading cases which affect antenna performances could be combined in the optimisation mathematical model. An important aspect to the work is the establishment of evaluation criteria to optimise the design of a system. Such an optimisation procedure would satisfy extremely high design requirements. An 8m antenna structure is significantly optimised and the results are given.

Chondrosarcoma is a malignant disease of cartilage. Systemic embolisation usually arises from cancerous invasion of pulmonary vessels or the left atrium but cerebral embolisation or ischaemia is rarely recognised. We report a man with left leg amputation for tibial myxoid chondrosarcoma who suffered multiple cerebral embolisms one year later. Cerebral angiography and aortogram did not reveal luminal stenosis and a cardiac survey was normal. Lupus anticoagulant (LAC) and a prolonged activated partial thromboplastin time were detected. A molecular mimicry between prothrombin and paracrine hormones may have accounted for his LAC. A procoagulant autoantibody reacting against metastatic cancer cells may contribute to cancerous thrombosis, such as in chondrosarcoma.

Interleukin-3 receptor (IL-3R) proteins are over-expressed on blasts and cancer stem cells of multiple hematologic malignancies. The recombinant diphtheria toxin fusion protein, DT388IL3, specifically targets IL-3R and is composed of the catalytic and translocation domains of diphtheria toxin (DT388) fused to human interleukin-3 (IL3). DT388IL3 demonstrated selective toxicity to acute myeloid leukemia (AML) stem cells both in vitro and in vivo, and was prepared for a Phase I clinical study in AML and myelodysplasia (MDS) patients. FDA approval (BB IND#11314) and IRB approvals were obtained. 80 AML and MDS patients were screened and 38 AML and 3 MDS patients were treated. The median age of treated patients was 62 years (range, 25–81 years). There were 22 males and 19 females. AML disease was de novo in 5, 1st relapse in 12, 2nd relapse in 8, and refractory in 12. MDS disease was high-grade in one and intermediate-grade in 2. Five AML patients had a history of MDS, and one had a history of secondary AML. One patient each had previously received an autologous or allogeneic stem cell transplant. AML cytogenetics was unfavorable in 15, intermediate in 21, and not done in 2. Seven patients were treated with 4 ug/kg, eight patients with 5.3 ug/kg, thirteen patients with 7.1 ug/kg, seven with 9.4 ug/kg, and six with 12.5 ug/kg DT388IL3 for up to six treatments (one cycle). Of note, patients have not yet received a second cycle. Drug-related toxicities were mild to moderate and transient including fever, chills, hypotension, transaminasemia, hypoxemia, and hypoalbuminemia. Pretreatment anti-DT antibody levels ranged from 0 – 9.6ug/mL (mean = 2.3ug/mL); day 15 post-treatment antibody levels were 0 – 600ug/mL (mean = 92ug/mL); day 30 antibody levels were 1.1 – 306ug/mL (mean = 82ug/mL). Day 1 Cmax ranged from 0 – 350 ng/mL and correlated with dose; Day 12 Cmax ranged from 0 – 179 ng/mL and correlated with Day 12 anti-DT antibody levels. Development of anti-DT antibody levels at Day 15 and 30 did not interfere with response. Consistent with an absence of toxicity to normal hematopoietic progenitors, responses occurred in the absence of prolonged myelosuppression. Among 38 evaluable AML patients, we have observed one CR of 8 months duration, 2 partial remissions (PRs) lasting one and three months, and 3 minimal responses with clearance of peripheral blasts and marrow blast cytoreductions of 89%, 90%, and 90% lasting one to two months. In one evaluable MDS patient, we achieved a PR lasting four months with improvement in hematologic parameters and conversion to transfusion independence. Patient accrual is proceeding with correlative IL3R content of blasts and cancer stem cells. These results of activity and tolerability are encouraging and suggest that DT388IL3 may achieve a role in the management of patients with myeloid malignancies.

Interleukin-3 receptor (IL-3R) proteins are over-expressed on blasts and cancer stem cells of multiple hematologic malignancies. The recombinant diphtheria toxin fusion protein, DT388IL3, specifically targets IL-3R and is composed of the catalytic and translocation domains of diphtheria toxin (DT388) fused to human interleukin-3 (IL3). DT388IL3 demonstrated selective toxicity to acute myeloid leukemia (AML) stem cells both in vitroand in vivo, and was prepared for a Phase I clinical study in AML and myelodysplasia (MDS) patients. FDA approval (BB IND#11314) and IRB approvals were obtained. 80 AML and MDS patients were screened and 38 AML and 3 MDS patients were treated. The median age of treated patients was 62 years (range, 25–81 years). There were 22 males and 19 females. AML disease was de novoin 5, 1strelapse in 12, 2ndrelapse in 8, and refractory in 12. MDS disease was high-grade in one and intermediate-grade in 2. Five AML patients had a history of MDS, and one had a history of secondary AML. One patient each had previously received an autologous or allogeneic stem cell transplant. AML cytogenetics was unfavorable in 15, intermediate in 21, and not done in 2. Seven patients were treated with 4 ug/kg, eight patients with 5.3 ug/kg, thirteen patients with 7.1 ug/kg, seven with 9.4 ug/kg, and six with 12.5 ug/kg DT388IL3 for up to six treatments (one cycle). Of note, patients have not yet received a second cycle. Drug-related toxicities were mild to moderate and transient including fever, chills, hypotension, transaminasemia, hypoxemia, and hypoalbuminemia. Pretreatment anti-DT antibody levels ranged from 0 – 9.6ug/mL (mean = 2.3ug/mL); day 15 post-treatment antibody levels were 0 – 600ug/mL (mean = 92ug/mL); day 30 antibody levels were 1.1 – 306ug/mL (mean = 82ug/mL). Day 1 Cmax ranged from 0 – 350 ng/mL and correlated with dose; Day 12 Cmax ranged from 0 – 179 ng/mL and correlated with Day 12 anti-DT antibody levels. Development of anti-DT antibody levels at Day 15 and 30 did not interfere with response. Consistent with an absence of toxicity to normal hematopoietic progenitors, responses occurred in the absence of prolonged myelosuppression. Among 38 evaluable AML patients, we have observed one CR of 8 months duration, 2 partial remissions (PRs) lasting one and three months, and 3 minimal responses with clearance of peripheral blasts and marrow blast cytoreductions of 89%, 90%, and 90% lasting one to two months. In one evaluable MDS patient, we achieved a PR lasting four months with improvement in hematologic parameters and conversion to transfusion independence. Patient accrual is proceeding with correlative IL3R content of blasts and cancer stem cells. These results of activity and tolerability are encouraging and suggest that DT388IL3 may achieve a role in the management of patients with myeloid malignancies.