A remark on the Restricted Isometry Property in Orthogonal Matching Pursuit

This paper demonstrates that if the restricted isometry constant $\delta_{K+1}$ of the measurement matrix $A$ satisfies $$\delta_{K+1} < \frac{1}{\sqrt{K}+1},$$ then a greedy algorithm called Orthogonal Matching Pursuit (OMP) can recover every $K$--sparse signal $\mathbf{x}$ in $K$ iterations from A\x. By contrast, a matrix is also constructed with the restricted isometry constant $$\delta_{K+1} = \frac{1}{\sqrt{K}}$$ such that OMP can not recover some $K$-sparse signal $\mathbf{x}$ in $K$ iterations. This result positively verifies the conjecture given by Dai and Milenkovic in 2009

Influenza virus antigenic variation, host antibody production and new approach to control epidemics

Influenza is an infectious disease and can lead to life-threatening complications like pneumonia. The disease is caused by three types of RNA viruses called influenza types A, B and C, each consisting of eight negative single-stranded RNA-segments encoding 11 proteins. Current annual vaccines contain two type A strains and one type B strain and are capable of inducing strong antibody responses to both the surface glycoprotein hemagglutinin and the neuraminidase. While these vaccines are protective against vaccine viruses they are not effective against newly emerging viruses that contain antigenic variations known as antigenic drift and shift. In nature, environmental selection pressure generally plays a key role in selecting antigenic changes in the antigen determining spots of hemagglutinin, resulting in changes in the antigenicity of the virus. Recently, a new technology has been developed where influenza-specific IgG+ antibody-secreting plasma cells can be isolated and cloned directly from vaccinated humans and high affinity monoclonal antibodies can be produced within several weeks after vaccination. The new technology holds great promise for the development of effective passive antibody therapy to limit the spread of influenza viruses in a timely manner

Influenza virus antigenic variation, host antibody production and new approach to control epidemics

Influenza is an infectious disease and can lead to life-threatening complications like pneumonia. The disease is caused by three types of RNA viruses called influenza types A, B and C, each consisting of eight negative single-stranded RNA-segments encoding 11 proteins. Current annual vaccines contain two type A strains and one type B strain and are capable of inducing strong antibody responses to both the surface glycoprotein hemagglutinin and the neuraminidase. While these vaccines are protective against vaccine viruses they are not effective against newly emerging viruses that contain antigenic variations known as antigenic drift and shift. In nature, environmental selection pressure generally plays a key role in selecting antigenic changes in the antigen determining spots of hemagglutinin, resulting in changes in the antigenicity of the virus. Recently, a new technology has been developed where influenza-specific IgG+ antibody-secreting plasma cells can be isolated and cloned directly from vaccinated humans and high affinity monoclonal antibodies can be produced within several weeks after vaccination. The new technology holds great promise for the development of effective passive antibody therapy to limit the spread of influenza viruses in a timely manner

Phonological short-term memory capacity and non-adjacent dependency-learning

This study investigated the relationship between phonological short-term memory capacity and non-adjacent dependency-learning. Forty university students were exposed to four-element strings in which the first element was dependent to the last element. Participants were then tested with a discrimination task in which they were required to discriminate the trained dependencies from the untrained ones. Participants were also tested on their phonological short-term memory capacity and nonverbal intelligence. Results demonstrated that the performance of the discrimination task was positively correlated with the phonological short-term memory capacity. The study suggested that the non-adjacent dependency-learning performance increased with the phonological short-term memory capacity providing implication on typical and atypical language acquisition.published_or_final_versionSpeech and Hearing SciencesBachelorBachelor of Science in Speech and Hearing Science

School Dropouts and Conditional Cash Transfers: Evidence from a Randomized Controlled Trial in Rural China’s Junior High Schools.

Recent anecdotal reports suggest that dropout rates may be higher and actually increasing over time in poor rural areas. There are many reasons not to be surprised that there is a dropout problem, given the fact that China has a high level of poverty among the rural population, a highly competitive education system and rapidly increasing wages for unskilled workers. The overall goal of this study is to examine if there is a dropout problem in rural China and to explore the effectiveness that a Conditional Cash Transfer (CCT) program could have on dropouts (and mechanism by which the CCT might affect drop outs). To meet this objective, we conducted a randomized controlled trial (RCT) of a CCT using a sample of 300 junior high school students in a nationally-designated poor county in Northwest China. Using our data, we found that the annual dropout rate in the study county was high, about 7%. We find, however, that a CCT program reduces drop outs by 60%; the dropout rate is 13.3% in the control group and 5.3 % in the treatment group. The program is most effective in the case of girls, younger students and the poorest performing students.

School dropouts and conditional cash transfers: evidence from a randomized controlled trial in rural China's junior high schools.

Recent anecdotal reports suggest that dropout rates may be higher and actually increasing over time in poor rural areas. There are many reasons not to be surprised that there is a dropout problem, given the fact that China has a high level of poverty among the rural population, a highly competitive education system and rapidly increasing wages for unskilled workers. The overall goal of this study is to examine if there is a dropout problem in rural China and to explore the effectiveness that a Conditional Cash Transfer (CCT) program could have on dropouts (and mechanism by which the CCT might affect drop outs). To meet this objective, we conducted a randomized controlled trial (RCT) of a CCT using a sample of 300 junior high school students in a nationally-designated poor county in Northwest China. Using our data, we found that the annual dropout rate in the study county was high, about 7.0%. We find, however, that a CCT program reduces drop outs by 60%; the dropout rate is 13.3% in the control group and 5.3 % in the treatment group. The program is most effective in the case of girls, younger students and the poorest performing students.

Do Poor Students Benefit from China’s Merger Program? Transfer Path and Educational Performance.

Aiming to provide better education facilities and improve the educational attainment of poor rural students, China’s government has been merging remote rural primary schools to centralized village, town, or county schools since the late 1990s. To accompany the policy, boarding facilities have been constructed that allow (mandate) primary school-aged children to live at school rather than at home. More generally, there also have been efforts to improve rural schools, especially those in counties and towns. Unfortunately, little empirical work has been available to evaluate the impact of the new merger and investment programs on the educational performance of students. Drawing on a unique dataset that records both the path by which students navigate their primary school years (i.e., which different types of schools did students attend) as well as math test scores in three poverty-stricken counties, we use descriptive statistics and multivariate analysis (both OLS and covariate matching) to analyze the relationship between different transfer paths and student educational performance. This allows us to examine the costs and benefits of the school merger and investment programs. The results of the analysis show that students who attend county schools perform systematically better than those attend village or town schools. However, completing primary school in town schools seems to have no effect on students’ academic performance. Surprisingly, starting primary education in a teaching point does not hurt rural students; on the contrary, it increases their test scores in some cases. Finally, in terms of the boarding effect, the neutral estimate in OLS and the negative estimate in covariate matching results confirm that boarding at school does not help the students; in some cases it may even reduce their academic performance.

A new proof of some polynomial inequalities related to pseudo-splines

AbstractPseudo-splines of type I were introduced in [I. Daubechies, B. Han, A. Ron, Z. Shen, Framelets: MRA-based constructions of wavelet frames, Appl. Comput. Harmon. Anal. 14 (2003) 1–46] and [Selenick, Smooth wavelet tight frames with zero moments, Appl. Comput. Harmon. Anal. 10 (2000) 163–181] and type II were introduced in [B. Dong, Z. Shen, Pseudo-splines, wavelets and framelets, Appl. Comput. Harmon. Anal. 22 (2007) 78–104]. Both types of pseudo-splines provide a rich family of refinable functions with B-splines, interpolatory refinable functions and refinable functions with orthonormal shifts as special examples. In [B. Dong, Z. Shen, Pseudo-splines, wavelets and framelets, Appl. Comput. Harmon. Anal. 22 (2007) 78–104], Dong and Shen gave a regularity analysis of pseudo-splines of both types. The key to regularity analysis is Proposition 3.2 in [B. Dong, Z. Shen, Pseudo-splines, wavelets and framelets, Appl. Comput. Harmon. Anal. 22 (2007) 78–104], which also appeared in [A. Cohen, J.P. Conze, Régularité des bases d'ondelettes et mesures ergodiques, Rev. Mat. Iberoamericana 8 (1992) 351–365] and [I. Daubechies, Ten Lectures on Wavelets, CBMS-NSF Series in Applied Mathematics, SIAM, Philadelphia, 1992] for the case l=N−1. In this note, we will give a new insight into this proposition