AIDing Contraception: HIV and Recent Trends in Abortion Rates

Since the onset of HIV/AIDS awareness in the early 1980s, much attention has centered around the substantial negative effects of the disease throughout the world. This paper provides evidence of a secondary effect the disease has had on sexual behavior in the United States. Using a difference-in-differences estimation framework and state level data, we show that the perceived threat of HIV resulted in a drop in unwanted pregnancies, as demonstrated by a lower incidence of abortions. Our results suggest that each additional reported case of HIV per 1,000 individuals resulted in 85.5 fewer abortions per 1,000 live births.

On the Benevolence Heart of the Preschool Teacher

Early childhood education is a meaningful activity for the enlightenment and cultivation of young children’s minds. The benevolence heart of preschool teachers should be the necessary prerequisites and core character for preschool teachers to engage in educational and teaching activities. It is not only the lofty expectation of society and kindergarten education for preschool teachers’ professional quality, but also the “unique” virtue of preschool teachers’ profession, emphasizing the harmony of material and spiritual, perceptual and rational qualities. Which is manifested in love with oneself, children and the cause of early childhood education, etc. The benevolence heart of the preschool teacher’s which have the characteristics of empathy, tolerance, caring and alertness. The formation of the benevolent heart of preschool teachers is of great significance to the development of children’s physical and mental health and the professional development of the self. The cultivation path includes preschool teachers’ self-cultivation of morality, the harmonious guidance of the social public opinion environment, the creation of scientific kindergarten culture of benevolence, and the construction of a perfect preschool teacher professional development system

Cost-Effective Signal Processing Algorithms for Physical-Layer Security in Wireless Networks

Data privacy in traditional wireless communications is accomplished by cryptography techniques at the upper layers of the protocol stack. This thesis aims at contributing to the critical security issue residing in the physical-layer of wireless networks, namely, secrecy rate in various transmission environments. Physical-layer security opens the gate to the exploitation of channel characteristics to achieve data secure transmission. Precoding techniques, as a critical aspect in pre-processing signals prior to transmission has become an effective approach and recently drawn significant attention in the literature. In our research, novel non-linear precoders are designed focusing on the improvement of the physical-layer secrecy rate with consideration of computational complexity as well as the Bit Error Ratio (BER) performance. In the process of designing the precoder, strategies such as Lattice Reduction (LR) and Artificial Noise (AN) are employed to achieve certain design requirements. The deployment and allocation of resources such as relays to assist the transmission also have gained significant interest. In multiple-antenna relay networks, we examine various relay selection criteria with arbitrary knowledge of the channels to the users and the eavesdroppers. Furthermore, we provide novel effective relay selection criteria that can achieve a high secrecy rate performance. More importantly they do not require knowledge of the channels of the eavesdroppers and the interference. Combining the jamming technique with resource allocation of relay networks, we investigate an opportunistic relaying and jamming scheme for Multiple-Input Multiple-Output (MIMO) buffer-aided downlink relay networks. More specifically, a novel Relaying and Jamming Function Selection (RJFS) algorithm as well as a buffer-aided RJFS algorithm are developed along with their ability to achieve a higher secrecy rate. Relying on the proposed relay network, we detail the characteristics of the system, under various relay selection criteria, develop exhaustive search and greedy search-based algorithms, with or without inter-relay Interference Cancellation (IC)

The Connotation, Basic Characteristics and Generation Path of Cloud Classroom Teaching Culture

Cloud classroom teaching culture is a special cultural form of teaching culture in cloud classroom. It is closely related to modern high-tech information technology and multimedia environment, containing both traditional cultural forms in the marks of modern multimedia technology and information environment, and includes modern new high-tech information technology and multimedia environment. Interpreting the connotation of the cloud of classroom teaching culture, analyzing the cloud classroom teaching culture of five basic characteristics: technical, across time and space, visibility, sharing, diversity, and put forward the cloud classroom teaching culture of five generated path: positioning cloud point to the spirit of classroom teaching culture, shape the new teaching idea; Implement the material culture construction of cloud classroom teaching and lay the foundation for the classroom teaching; To build up the technical and cultural features of cloud classroom teaching and highlight the cultural characteristics of classroom teaching; Cultivate the behavior culture atmosphere of cloud classroom teaching and gain insight into the details of classroom teaching; To construct the system culture system of cloud classroom teaching and to perceive the standardization of classroom teaching

The Cultivation of Approaches to Learning, so that Children Lifelong Benefits - Reading the Feel of Enthusiastic and Engaged Learners: Approaches to Learning in the Early Childhood Classroom

Approaches to learning is not only the basic quality of children’s physical and mental development, but also the key to determine the quality of children’s learning. However, there are still some phenomena such as inattention, inactive learning attitude and lack of good learning habits among Chinese children. How to do it? Marilou Hyson, a famous American scholar, wrote “Enthusiastic and Engaged Learners: Approaches to Learning in the Early Childhood Classroom” undoubtedly gives us profound inspiration. In order to comply with the new requirements of improving the quality of preschool education and the implementation of preschool education, and to correctly consider the positive learning quality and children’s education, as a kindergarten teacher should recognize the value of active learning quality and cultivate the potential of children; pay attention to children’s education and care for children’s growth environment; comply with the law of growth and stimulate children to actively learn quality

Carbon Stocks across a Fifty Year Chronosequence of Rubber Plantations in Tropical China

Transition from forest to rubber (Hevea brasiliensis Muell. Arg.) plantation has occurred in tropical China for decades. Rubber has been planted on 1 million ha to provide raw materials to the rubber industry. The role of various-aged rubber plantations in carbon (C) sequestration remains unclear. The biomass C accumulation including latex C and C distribution in soil of five different-aged stands (7, 13, 19, 25 and 47 years old) were examined. The total biomass C stock (TBC) and total net primary productivity (NPPtotal), whether with or without latex C, had a close quadratic relationship with stand age. Regardless of stand age, around 68% of the C was stored in aboveground biomass, and NPPlatex contributed to approximately 18% of C sequestration. Soil organic carbon stock in the 100-cm depth remained relatively stable, but it lost about 16.8 Mg ha−1 with stand age. The total ecosystem C stock (TEC) across stands averaged 159.6, 174.4, 229.6, 238.1 and 291.9 Mg ha−1, respectively, of which more than 45% was stored in the soil. However, biomass would become the major C sink rather than soil over a maximal rubber life expectancy. Regression analysis showed that TEC for rubber plantation at 22 years is comparable to a baseline of 230.4 Mg ha−1 for tropical forest in China, and would reach the maximum value at around 54 years. Therefore, rubber plantation can be considered as alternative land use without affecting net forest ecosystem C storage. In addition to the potential C gains, a full set of ecosystem and economic properties have to be quantified in order to assess the trade-offs associated with forest-to-rubber transition

Coronavirus Replicase-Reporter Fusions Provide Quantitative Analysis of Replication and Replication Complex Formation

The replication of coronaviruses occurs in association with multiple virus-induced membrane structures that evolve during the course of infection; however, the dynamics of this process remain poorly understood. Previous studies of coronavirus replication complex organization and protein interactions have utilized protein overexpression studies and immunofluorescence of fixed cells. Additionally, live-imaging studies of coronavirus replicase proteins have used fluorescent reporter molecules fused to replicase proteins, but expressed from nonnative locations, mostly late-transcribed subgenomic mRNAs, in the presence or absence of the native protein. Thus, the timing and targeting of native replicase proteins expressed in real time from native locations in the genome remain unknown. In this study, we tested whether reporter molecules could be expressed from the replicase polyprotein of murine hepatitis virus as fusions with nonstructural protein 2 or 3 and whether such reporters could define the targeting and activity of replicase proteins during infection. We demonstrate that the fusion of green fluorescent protein and firefly luciferase with either nonstructural protein 2 or 3 is tolerated and that these reporter-replicase fusions can be used to quantitate replication complex formation and virus replication. The results show that the replicase gene has flexibility to accommodate a foreign gene addition and can be used directly to study replicase complex formation and evolution during infection as well as to provide highly sensitive and specific markers for protein translation and genome replication

Femtosecond laser written optical waveguides in z-cut MgO:LiNbO3 crystal: Fabrication and optical damage investigation

We report on the fabrication of the dual-line waveguides and cladding waveguide in z-cut MgO:LiNbO3 crystal by femtosecond laser inscription. Due to the diverse modification of refractive index along TE/TM polarization induced by femtosecond laser pulses, the two geometries exhibit different guiding performances: the dual-line waveguides only support extraordinary index polarization, whilst the depressed cladding waveguide supports guidance along both extraordinary and ordinary index polarizations. The measured optical damage of these waveguides at the wavelength of 532 nm is higher than that of the previously reported ion-implanted waveguides in Zr-doped LiNbO3. The propagation loss of depressed cladding waveguide is measured as low as 0.94 dB/cm at 632.8 nm wavelength. It is found that the optical damage threshold (∼105 W/cm2) of the dual-line waveguide is one order of magnitude higher than that of the cladding waveguide (∼104 W/cm2).The work was supported by the National Natural Science Foundation of China (Nos.11274203, and 11511130017) and Spanish Ministerio de Educación y Ciencia (FIS2013-44174-P)