Aneuploidy among androgenic progeny of hexaploid triticale (XTriticosecale Wittmack).

Doubled haploids are an established tool in plant breeding and research. Of several methods for their production, androgenesis is technically simple and can efficiently produce substantial numbers of lines. It is well suited to such crops as hexaploid triticale. Owing to meiotic irregularities of triticale hybrids, aneuploidy may affect the efficiency of androgenesis more severely than in meiotically stable crops. This study addresses the issue of aneuploidy among androgenic regenerants of triticale. Plant morphology, seed set and seed quality were better predictors of aneuploidy, as determined cytologically, than flow cytometry. Most aneuploids were hypoploids and these included nullisomics, telosomics, and translocation lines; among 42 chromosome plants were nulli-tetrasomics. Rye chromosomes involved in aneuploidy greatly outnumbered wheat chromosomes; in C(0) rye chromosomes 2R and 5R were most frequently involved. While the frequency of nullisomy 2R was fairly constant in most cross combinations, nullisomy 5R was more frequent in the most recalcitrant combination, and its frequency increased with time spent in culture with up to 70% of green plants recovered late being nullisomic 5R. Given that 5R was not involved in meiotic aberrations with an above-average frequency, it is possible that its absence promotes androgenesis or green plant regeneration. Overall, aneuploidy among tested combinations reduced the average efficiency of double haploid production by 35% and by 69% in one recalcitrant combination, seriously reducing the yield of useful lines

Jatropha curcas protoplast isolation and inhibitory effects of culture

Improvement on the sub-tropical plant Jatropha curcas may increase the use of this drought tolerant oilseed crop for the production of biodiesel. One of the methods for enhancing a species is through genetic manipulation of the protoplast. Isolating protoplasts is challenging and culturing has many obstacles similar to those seen in tissue culture, such as oxidative browning. Successful isolation of J. curcas leaf protoplasts resulted in an average of 3.23 x 106 viable protoplasts/mL. However, protoplasts diminished within 2 days after culturing. A review of the potential solutions used for overcoming the inhibitory effects of culture may reveal further insight on the culturing of J. curcas protoplasts

SOFTWARE DEFINED CUSTOMIZATION OF NETWORK PROTOCOLS WITH LAYER 4.5

The rise of software defined networks, programmable data planes, and host level kernel programmability gives rise to highly specialized enterprise networks. One form of network specialization is protocol customization, which traditionally extends existing protocols with additional features, primarily for security and performance reasons. However, the current methodologies to deploy protocol customizations lack the agility to support rapidly changing customization needs. This dissertation designs and evaluates the first software-defined customization architecture capable of distributing and continuously managing protocol customizations within enterprise or datacenter networks. Our unifying architecture is capable of performing per-process customizations, embedding per-network security controls, and aiding the traversal of customized application flows through otherwise problematic middlebox devices. Through the design and evaluation of the customization architecture, we further our understanding of, and provide robust support for, application transparent protocol customizations. We conclude with the first ever demonstration of active application flow "hot-swapping" of protocol customizations, a capability not currently supported in operational networks.Office of Naval Research, Arlington, VA 22203Lieutenant Commander, United States NavyApproved for public release. Distribution is unlimited

Data Exfiltration via Flow Hijacking at the Socket Layer

The severity of data exfiltration attacks is well known, and operators have begun deploying elaborate host and network security controls to counter this threat. Consequently, malicious actors spare no efforts finding methods to obfuscate their attacks within common network traffic. In this paper, we expose a new type of application transparent, kernel level data exfiltration attacks. By embedding data into application messages while they are held in socket buffers outside of applications, the attacks have the flexibility to hijack flows of multiple distinct applications at a time. Furthermore, we assess the practical implications of the attacks using a testbed emulating a typical data exfiltration scenario. We first prototype required attack functionalities with existing Layer 4.5 application message customization software, and then perform flow hijacking experiments with respect to six common application protocols. The results confirm the flexibility of socket layer attacks and their ability to evade typical security controls

Mapping translocation breakpoints using a wheat microarray

We report mapping of translocation breakpoints using a microarray. We used complex RNA to compare normal hexaploid wheat (17 000 Mb genome) to a ditelosomic stock missing the short arm of chromosome 1B (1BS) and wheat-rye translocations that replace portions of 1BS with rye 1RS. Transcripts detected by a probe set can come from all three Triticeae genomes in ABD hexaploid wheat, and sequences of homoeologous genes on 1AS, 1BS and 1DS often differ from each other. Absence or replacement of 1BS therefore must sometimes result in patterns within a probe set that deviate from hexaploid wheat. We termed these ‘high variance probe sets’ (HVPs) and examined the extent to which HVPs associated with 1BS aneuploidy are related to rice genes on syntenic rice chromosome 5 short arm (5S). We observed an enrichment of such probe sets to 15–20% of all HVPs, while 1BS represents ∼2% of the total genome. In total 257 HVPs constitute wheat 1BS markers. Two wheat-rye translocations subdivided 1BS HVPs into three groups, allocating translocation breakpoints to narrow intervals defined by rice 5S coordinates. This approach could be extended to the entire wheat genome or any organism with suitable aneuploid or translocation stocks

Populations of doubled haploids for genetic mapping in hexaploid winter triticale.

To create a framework for genetic dissection of hexaploid triticale, six populations of doubled haploid (DH) lines were developed from pairwise hybrids of high-yielding winter triticale cultivars. The six populations comprise between 97 and 231 genotyped DH lines each, totaling 957 DH lines. A consensus genetic map spans 4593.9 cM is composed of 1576 unique DArT markers. The maps reveal several structural rearrangements in triticale genomes. In preliminary tests of the populations and maps, markers specific to wheat segments of the engineered rye chromosome 1R (RM1B) were identified. Example QTL mapping of days to heading in cv. Krakowiak revealed loci on chromosomes 2BL and 2R responsible for extended vernalization requirement, and candidate genes were identified. The material is available to all parties interested in triticale genetics

The Importance of the Interface between Humans and Computers on the Effectiveness of eHRM

Technology has had a dramatic impact on the practice of human resources, and its impact is rapidly increasing. Even so, little research has examined how to apply information systems and human-computer interaction principles to designing human resource information systems. In this paper, we focus more closely on the role that the interface between the computer and human play in the success of electronic human resource management. Specifically, we a) briefly review the individual requirements of several eHRM functions (e.g., e-recruiting, e-selection, e-learning, e- compensation/benefits), b) consider how an understanding of human computer interaction can facilitate the success of these systems, c) reviews research on technical issues associated with eHRM, and d) highlight how applying HCI principles can increase their effectiveness. In addition, we introduce the remaining seven papers in the special issue