Ingenious Sandwich-like Adhesive Films and Controllable Introduction of Fluorine-Containing Groups toward Strong Adhesive Strength and Low Dielectric Characteristics

In the manufacturing field of high-frequency print circuit boards (HFPCBs), traditional adhesive films (such as epoxy resin and polyimide adhesive films) have attracted enormous attention because of their superior adhesive property. However, their molecular chains intrinsically contained numerous polar groups (carboxyl, carbonyl, and amino), which markedly increased the dielectric constant (Dk) and dielectric loss (Df) of the adhesive film, causing miserable deterioration of the fidelity and transmission rate of signals. In this work, a novel sandwich-like adhesive film was felicitously designed and fabricated by double-sided coating. The core layer as a supporting structure was a polytetrafluoroethylene film with a low dielectric constant and low dielectric loss, and the surface layer as a principal part of the adhesive function was polybutadiene with high vinyl content. Moreover, to further improve the interfacial adhesive strength between the adhesive film and copper foil, the fluorine-containing groups were controllably introduced onto the surface of the sandwich-like adhesive film via environment-friendly plasma treatment. Based on low polarizability and only superficial distribution of the fluorine-containing groups, the interfacial adhesive strength of the film greatly improved from 0.41 to 1.09 N/mm. Unexpectedly, the high-frequency dielectric properties slightly changed (without treatment Dk = 2.42 and Df = 0.0036 at 10 GHz, treatment Dk = 2.46 and Df = 0.0039 at 10 GHz). This work provided the key adhesive materials for the next generation of high-throughput data transmission equipment, remote sensing controllers, and unmanned aerial vehicles in high-frequency ranges

Genetic Mapping and Characteristics of Genes Specifically or Preferentially Expressed during Fiber Development in Cotton

<div><p>Cotton fiber is an ideal model to study cell elongation and cell wall construction in plants. During fiber development, some genes and proteins have been reported to be specifically or preferentially expressed. Mapping of them will reveal the genomic distribution of these genes, and will facilitate selection in cotton breeding. Based on previous reports, we designed 331 gene primers and 164 protein primers, and used single-strand conformation polymorphism (SSCP) to map and integrate them into our interspecific BC₁ linkage map. This resulted in the mapping of 57 loci representing 51 genes or proteins on 22 chromosomes. For those three markers which were tightly linked with quantitative trait loci (QTLs), the QTL functions obtained in this study and gene functions reported in previous reports were consistent. Reverse transcription-polymerase chain reaction (RT-PCR) analysis of 52 polymorphic functional primers showed that 21 gene primers and 17 protein primers had differential expression between Emian22 (<em>Gossypium hirsutum</em>) and 3–79 (<em>G. barbadense</em>). Both RT-PCR and quantitative real-time PCR (qRT-PCR) analyses of the three markers tightly linked with QTLs were consistent with QTL analysis and field experiments. Gene Ontology (GO) categorization revealed that almost all 51 mapped genes belonged to multiple categories that contribute to fiber development, indicating that fiber development is a complex process regulated by various genes. These 51 genes were all specifically or preferentially expressed during fiber cell elongation and secondary wall biosynthesis. Therefore, these functional gene-related markers would be beneficial for the genetic improvement of cotton fiber length and strength.</p> </div

Details of the three QTLs tightly linked with functional markers.

<p>Details of the three QTLs tightly linked with functional markers.</p

RT-PCR analysis of 42 polymorphic and productive primers.

<p>Numbers on the top represent 0DPA, 5DPA, 10DPA, 15DPA, 20DPA and 25DPA, respectively. Primers, which have either differential expression tendencies or obvious differential expression levels between Emian22 and 3–79, were classified into the obvious difference category. Primers with minor difference in expression levels between Emian22 and 3–79 were classified into the minor difference category. Primers with neither differential expression tendencies nor differential expression levels between Emian22 and 3–79 were classified into the no difference category. Gene primers and protein primers are labeled on the left.</p

Locations of polymorphic markers and fiber-related QTLs on the BC₁ genetic linkage map.

<p>Gene markers are underlined and in bold. Protein markers are underlined, italicized and in bold.</p

Additional file 3: Table S3. of Genomic heterozygosity and hybrid breakdown in cotton (Gossypium): different traits, different effects

MHIs in (E3) F2 population. (XLS 14 kb

Tentative transmembrane model of H⁺-PPase from <i>Sophora alopecuroid</i> generated by TMHMM online.

<p>There are 13 putative transmembrane regions. D1, D2 and D3 with solid rectangles are previously identified domains <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0070099#pone.0070099-Hedlund1" target="_blank">[26]</a>, and P1 and P2 with dotted rectangles are putative motifs that we predicted.</p

Isolation and Characterization of a Conserved Domain in the Eremophyte H⁺-PPase Family

<div><p>H⁺-translocating inorganic pyrophosphatases (H⁺-PPase) were recognized as the original energy donors in the development of plants. A large number of researchers have shown that H⁺-PPase could be an early-originated protein that participated in many important biochemical and physiological processes. In this study we cloned 14 novel sequences from 7 eremophytes: <i>Sophora alopecuroid</i> (<i>Sa</i>), <i>Glycyrrhiza uralensis</i> (<i>Gu</i>), <i>Glycyrrhiza inflata</i> (<i>Gi</i>), <i>Suaeda salsa</i> (<i>Ss</i>), S<i>uaeda rigida</i> (<i>Sr</i>), <i>Halostachys caspica</i> (<i>Hc</i>), and <i>Karelinia caspia</i> (<i>Kc</i>). These novel sequences included 6 ORFs and 8 fragments, and they were identified as H⁺-PPases based on the typical conserved domains. Besides the identified domains, sequence alignment showed that there still were two novel conserved motifs. A phylogenetic tree was constructed, including the 14 novel H⁺-PPase amino acid sequences and the other 34 identified H⁺-PPase protein sequences representing plants, algae, protozoans and bacteria. It was shown that these 48 H⁺-PPases were classified into two groups: type I and type II H⁺-PPase. The novel 14 eremophyte H⁺-PPases were classified into the type I H⁺-PPase. The 3D structures of these H⁺-PPase proteins were predicted, which suggested that all type I H⁺-PPases from higher plants and algae were homodimers, while other type I H⁺-PPases from bacteria and protozoans and all type II H⁺-PPases were monomers. The 3D structures of these novel H⁺-PPases were homodimers except for <i>SaVP3</i>, which was a monomer. This regular structure could provide important evidence for the evolutionary origin and study of the relationship between the structure and function among members of the H⁺-PPase family.</p></div

Phylogenetic tree of H⁺-PPase sequences from some representative species by NJ and a 3D structure prediction by Swiss Model.

<p>Purple indicates novel cloned H⁺-PPases from 7 eremophytes. The type I H⁺-PPases were made up of a, b, c and d subgroups. The a subgroup is made up of <i>ScVP</i> (ADQ00196.1), <i>HcVP</i> (ABO45933.1), <i>KfVP</i> (ABK91685.1), <i>ChrVP</i> (AAM97920.1), <i>SsVP2</i>, <i>HcVP3</i>, <i>MtVP</i> (XP_003609464.1), <i>SaVP1</i>, <i>SaVP2</i>, <i>GuVP1</i>, <i>GiVP1</i>, <i>GhVP</i> (ADN96173.1), <i>NtVP</i> (CAA54869.1), and <i>AVP1</i> (NP_173021.1). The b subgroup includes <i>OsVP</i> (BAD25066.1), <i>BvVP</i> (AAA61610.1), <i>HcVP</i>1, <i>HcVP</i>2, <i>SrVP</i>1, <i>SsVP</i>1, <i>GuVP</i>2, <i>KcVP1</i> and <i>KcVP2</i>. The c subgroup is formed by <i>BdVP</i> (XP_003564217.1), <i>ZmVP</i> (ACN33286.1), <i>SbVP</i> (ADJ67258.1), <i>ZxVP</i> (ABU92563.1), <i>GmVP</i> (XP_003555808.1), <i>PtVP</i> (XP_002318956.1), <i>RcVP</i> (XP_002512502.1). And the d is formed by <i>ChlrVP</i> (XP_001694682.1), SaVP3, <i>PbVP</i> (XP_676243.1), <i>RhmVP</i> (YP_004826142.1), <i>ChpVP</i> (YP_001959520.1), <i>ThmVP</i> (YP_003676510.1), <i>ElVP</i> (YP_003958643.1), <i>HhVP</i> (YP_003994656.1), <i>FvVP</i> (ZP_08694297.1). The type II H⁺-PPase includes <i>AVP2</i> (NM_101539), <i>MpVP</i> (XM_003059582.1), <i>RhrVP</i> (YP_426905.1), <i>MgVP</i> (CAM76045.1), <i>NeVP</i> (YP_747021.1), <i>GsVP</i> (NP_954331.1), <i>AbVP</i> (EKS38298.1), <i>RhpVP</i> (Q8KY01.1), and <i>MmVP</i> (YP_865668.1). 3D structures including type I H⁺-PPase <i>ScVP1</i> (ADQ00196.1, <i>Suaeda corniculata</i>), <i>OsVP1</i> (BAD25066.1, <i>Oryza sativa</i>), <i>ChrVP1</i> (XP_001694682.1, <i>Chlamydomonas reinhardtii</i>), <i>SrVP1</i>, <i>SaVP1</i> and <i>KcVP1</i> are present as homodimers. The others are monomer H⁺-PPase, they are <i>AVP2</i> (NM_101539, <i>Arabidopsis thaliana 2</i>), <i>SaVP3</i> and <i>MgVP2</i> (CAM76045.1, <i>Magnetospirillum gryphiswaldense</i>). The <i>SaVP1-1</i> was truncated according to the sequence of <i>SaVP3</i>. Number 1, 2 and 3 and black arrows in the 3D structure showed different regions.</p

The sequence and transmembrane prediction of <i>SaVP1</i>.

<p>There are 13 transmembrane regions in <i>SaVP1</i> which are marked with red Arabic numerals. The yellow marked K is group I, and the green marked K is group II. The purple marked segment consists of identified conserved domains. The grey marked segment consists of supposed novel conserved motifs.</p