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In this paper, the symmetric positive semidefinite Procrustes problem is considered. By using matrix inner product and matrix decomposition theory, an explicit expression of the solution is given. Based on the explicit expression given in this paper, it is easy to derive the explicit expression of the solution given by Woodgate [K.G. Woodgate. Least-squares solution of F = PG over positive semidefinite symmetric P . Linear Algebra Appl., 245:171–190, 1996.] and by Liao [A.P. Liao. On the least squares problem of a matrix equation. J. Comput. Math., 17:589–594, 1999.] for the Procrustes problem in some special cases. The explicit expression given in this paper also shows that the solution of the special inverse eigenvalue problem considered by Zhang [L. Zhang. A class of inverse eigenvalue problem for symmetric nonnegative definite matrices. J. Hunan Educational Inst., 2:11–17, 1995 (in Chinese).] can be computed exactly. Examples to illustrate the correctness of the theory results are given.

Plants deploy different strategies to respond and adapt to various stresses. Given that stresses affect plant growth and activity, the responses and tolerance of crops to stresses must be improved through genetic engineering. Inducible promoters, which have vital roles in gene expression and function, are highly desired in biotechnology applications. Thus, novel inducible promoters must be isolated and identified for genetic engineering to improve crop stress responses and tolerance. OsRhoGAPs are involved in plant defense against diverse stresses. In this study, we identified OsRhoGAP2, which is preferentially expressed in rice inflorescences. We isolated the OsRhoGAP2 promoter and analyzed its functions in transgenic Arabidopsis. We fused the GUS reporter with six 5′ deletion fragments (gp1–gp6) of the OsRhoGAP2 promoter with different lengths. Through histochemical analysis, we detected GUS activity in the inflorescences of transgenic Arabidopsis containing gp1, gp3, gp4, and gp5 constructs but not in transgenic Arabidopsis containing gp2 and gp6 constructs. The GUS activity in transgenic plants containing gp1–gp6 constructs changed under different stress treatments. Bioinformatics analysis and experimental results revealed that the core fragment involved in the inflorescence-preferential expression of OsRhoGAP2 and stress responses may be located in the − 706 bp to + 1 bp, or the translated start site, of OsRhoGAP2. Results indicate that OsRhoGAP2 has a conserved role in stress tolerance and exhibits tissue-specific expression patterns in several plant species. This work provides novel insights into the appropriate promoter resources for plant genetic transformation and useful references for biotechnologists to improve stress tolerance in rice.

n this paper, an iterative method to solve one kind of nonlinear matrix equation is discussed. For each initial matrix with some conditions, the matrix sequences generated by the iterative method are shown to lie in a fixed open ball. The matrix sequences generated by the iterative method are shown to converge to the only solution of the nonlinear matrix equation in the fixed closed ball. In addition, the error estimate of the approximate solution in the fixed closed ball, and a numerical example to illustrate the convergence results are given.

e18003 Background: Medical advance in the recent decades has turned cancer into a chronic disease. At the same time, quality of life (LoF) during the treatment period has emerged as a new concern of cancer patients. Rehabilitation therapy, which can help patients conquer fear and be more engaged in the process, has gradually attracted more attentions in China. We designed a survey, for both the cancer patients and their families, to understand their view of the rehabilitation therapy. Methods: We sent paper-based surveys to volunteers consisted of cancer patients and their families. Majority of patients are from 10 cancer centers at the southwest region of China. The main cancer types are lung cancer, breast cancer and colon cancer. The survey questions focus on: patients and their families’ engagement of the treatment, their view on rehabilitation therapy, and their method preference for the rehabilitation therapy. Results: We sent 2,000 copies of the survey and received 1,920 valid inputs. Below are the key findings. 1. Their biggest concern: the outcome of the treatment 55.8%, side effects 19.7%, financial burden 12.8% and mental stress 11.5%. 2. The importance of the rehabilitation therapy as compared to traditional medical treatment, such as surgery and chemotherapy: equally important 67.8%, less important 17.7%, more important 10.1%, no preference 4.4%. 3. The necessity of rehabilitation therapy: very necessary 65.7%, somewhat necessary 22.7%, not necessary 11.6%. 4. The first three reasons for participating rehabilitation therapy: it helped go through the treatment 42.8%, it improved quality of life 31.6% and it helped release their mental stress 22.3%. 5. The best form to conduct rehabilitation therapy: face-to-face communicate with the doctors 60.6%, telecommunication 15.8% and combination of both 22.1%. Conclusions: The results of the survey strongly indicate the demands for rehabilitation therapy. Patients started to understand it – more than half of them think it is as important as the traditional medical treatment. Patients’ quality of life and mental health, which is part of the holistic treatment, are gradually recognized. Next, we plan to group our survey results by types of cancers, patients and their families’ genders and age, as well as the local economics, to better understand the data. We hope this study can serve as a data point to help build China’s rehabilitation therapy infrastructure.

Iron is the fourth most abundant element in the Earth's crust.Microbially mediated dissimilatory Fe(Ⅲ) reduction is the major process for Fe(Ⅲ) reduction in anoxic environment.This review introduces the classification and the diversity of dissimilatory Fe(Ⅲ)-reducing microorganisms.There are two major groups of Fe(Ⅲ)-reducing microorganisms:one is microorganisms which could conserve energy to support growth from Fe(Ⅲ) reduction,and the other is those which could not conserve energy to support growth from Fe(Ⅲ) reduction.Dissimilatory Fe(Ⅲ)-reducing microorganisms are interspersed throughout Bacteria,Archaea and Fungi and have physiological diversity.Geobacter and Shewanella are the two most well studied genera among all the Fe(Ⅲ)-reducing microorganisms.This also summarizes the strategies that dissimilatory Fe(Ⅲ)-reducing bacteria use to transfer electron to extracellular Fe(Ⅲ) oxide minerals as well as the energy-generating central metabolism models of dissimilatory Fe(Ⅲ)-reducing bacteria.Direct contact,cellular appendage production,electron shuttling and chelation are the four potential strategies for the respiration of dissimilatory Fe(Ⅲ)-reducing bacteria.In Geobacter,acetate and other electron donors are completely oxidized via the tricarboxylic acid(TCA) cycle,generating ATP primarily from oxidative phosphorylation,while substrate-level phosphorylation is the primary source of energy conservation during anaerobic respiration of Shewanella.In addition,the environmental significances of dissimilatory Fe(Ⅲ)-reducing microorganisms are reviewed.Fe(Ⅲ)-reducing microorganisms might be one of the first,if not the first,of microbes involved in microbial respiration in the archaean biosphere,which contributes to the decomposition of organic matter in modern sedimentary environments and inhibition of methane production,exerts a broad range of impacts on the behavior of trace elements and have great potential in the bioremediation and microbial fuel cells.Finally,perspectives in the molecular ecology of dissimilatory Fe(Ⅲ)-reducing bacteria studies are proposed,e.g.the community structure of dissimilatory Fe(Ⅲ)-reducing bacteria in paddy soils,the contribution of dissimilatory Fe(Ⅲ)-reducing bacteria in the C-Fe-N coupling and the mechanism of dissimilatory Fe(Ⅲ)-reducing bacteria in the bioremediation with electrode and solar energy.

As switched reluctance machines (SRM) generally offer a simple and robust design, they are very suitable for an aircraft main engine fuel pump drive which needs to be actuated by fault-tolerant drives. In this paper two different fault-tolerant SRM topologies for fuel pump drive in aircraft are analytical compared: Firstly a 6/4-topology with two identical motors on one axis as a dual-redundancy drive system, and secondly a dual-channel 12/8-topology, where one 3-phase-system uses every other stator tooth and the second 3-phase-system that provides redundancies uses the rest of the stator teeth. The first of two schemes is turned out to be the better solution concerning ruggedness, weight, inertia, torque quality and magnetic isolation.