Transposon mutagenesis in a hyper-invasive clinical isolate of Campylobacter jejuni reveals a number of genes with potential roles in invasion

Transposon mutagenesis has been applied to a hyper-invasive clinical isolate of Campylobacter jejuni, 01/51. A random transposon mutant library was screened in an in vitro assay of invasion and 26 mutants with a significant reduction in invasion were identified. Given that the invasion potential of C. jejuni is relatively poor compared to other enteric pathogens, the use of a hyper-invasive strain was advantageous as it greatly facilitated the identification of mutants with reduced invasion. The location of the transposon insertion in 23 of these mutants has been determined; all but three of the insertions are in genes also present in the genome-sequenced strain NCTC 11168. Eight of the mutants contain transposon insertions in one region of the genome (∼14 kb), which when compared with the genome of NCTC 11168 overlaps with one of the previously reported plasticity regions and is likely to be involved in genomic variation between strains. Further characterization of one of the mutants within this region has identified a gene that might be involved in adhesion to host cells

Striatal dopamine D1-type receptor availability: no difference from control but association with cortical thickness in methamphetamine users.

Chronic methamphetamine use poses potentially devastating consequences for directly affected individuals and for society. Lower dopamine D2-type receptor availability has been observed in striata of methamphetamine users as compared with controls, but an analogous comparison of D1-type receptors has been conducted only on post-mortem material, with no differences in methamphetamine users from controls in the caudate nucleus and putamen and higher D1-receptor density in the nucleus accumbens. Released from neurons when methamphetamine is self-administered, dopamine binds to both D1- and D2-type receptors in the striatum, with downstream effects on cortical activity. Thus, both receptor subtypes may contribute to methamphetamine-induced alterations in cortical morphology and behavior. In this study, 21 methamphetamine-dependent subjects and 23 healthy controls participated in positron emission tomography and structural magnetic resonance imaging for assessment of striatal D1- and D2-type receptor availability and cortical gray-matter thickness, respectively. Although D2-type receptor availability (BPnd) was lower in the methamphetamine group, as shown previously, the groups did not differ in D1-type BPnd. In the methamphetamine group, mean cortical gray-matter thickness was negatively associated with cumulative methamphetamine use and craving for the drug. Striatal D1-type but not D2-type BPnd was negatively associated with global mean cortical gray-matter thickness in the methamphetamine group, but no association was found between gray-matter thickness and BPnd for either dopamine receptor subtype in the control group. These results suggest a role of striatal D1-type receptors in cortical adaptation to chronic methamphetamine use

EFFECT OF SHADOWING AND MULTIPATH FADING ON THE AREA SPECTRAL FOR CELL-EDGE USERS IN HETEROGENEOUS NETWORKS

irrespective of their location. The traditional macro-only network have been proved ineffective when communication signal is required for users located in the cell edge and a certain distance away from the macrocell base station. This is because of excess attenuation of the signal due to fading and shadowing. Multipath fading and shadowing are major causes of performance degradation in mobile communication systems. This phenomenon which arises as a result of propagation effects (like scattering, diffraction and reflection), renders the traditional macro-only network communication with users far away from the macrocell base station and located in the cell edge less effective. The deployment of femtocells around the cell edge of this macrocell helps to reduce the effect of fading and shadowing thereby increasing the overall efficiency of the cellular network. Numerical simulation carried out for the macro-femto heterogeneous network using MATLAB shows how the effect of fading and shadowing was reduced. This holds a great promise for adaptive space-based wireless sensor networks, formation-flying satellites and constellations. http://dx.doi.org/10.4314/njt.v35i2.2

Rectifiability of Optimal Transportation Plans

The purpose of this note is to show that the solution to the Kantorovich optimal transportation problem is supported on a Lipschitz manifold, provided the cost is $C^{2}$ with non-singular mixed second derivative. We use this result to provide a simple proof that solutions to Monge's optimal transportation problem satisfy a change of variables equation almost everywhere

Phylogenetic And Molecular Variability Studies Reveal A New Genetic Clade Of Citrus Leprosis Virus C

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Citrus leprosis virus C (CiLV-C) causes a severe disease affecting citrus orchards in the Western hemisphere. This study reveals the molecular variability of the virus by analyzing four genomic regions (p29, p15, MP and RNA2-intergenic region) distributed over its two RNAs. Nucleotide diversity (pi) values were relatively low but statistically different over the analyzed genes and subpopulations, indicating their distinct evolutionary history. Values of pi(p29) and pi(MP) were higher than those of pi(p15) and pi(RNA2-IR), whereas pi(MP) was increased due to novel discovered isolates phylogenetically clustered in a divergent clade that we called SJP. Isolate BR_SP_SJP_01 RNA1 and RNA2 sequences, clade SJP, showed an identity of 85.6% and 88.4%, respectively, with those corresponding to CiLV-C, the type member of the genus Cilevirus, and its RNA2 5'-proximal region was revealed as a minor donor in a putative inter-clade recombination event. In addition to citrus, BR_SP_SJP_01 naturally infects the weed Commelina benghalensis and is efficiently transmitted by Brevipalpus yothersi mites. Our data demonstrated that negative selection was the major force operating in the evaluated viral coding regions and defined amino acids putatively relevant for the biological function of cilevirus proteins. This work provides molecular tools and sets up a framework for further epidemiological studies.8Conselho Nacional de Desenvolvimento Cientifico e Tecnologico [375843/2012-4, 481771/2013-1, 401564/2012-6]Fundacao de Apoio a Pesquisa no Estado de Sao Paulo [2012/18771-0, 2012/20667-7, 2014/08458-9]Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Affective state influences retrieval-induced forgetting for integrated knowledge

Selectively testing parts of learned materials can impair later memory for nontested materials. Research has shown that such retrieval-induced forgetting occurs for low-integrated materials but may be prevented for high-integrated materials. However, previous research has neglected one factor that is ubiquitous in real-life testing: affective stat

Assessment of optimum sowing time based on heat indices and row spacing for summer guar

A field experiment was conducted during summer seasons of 2013 to 2015 on clayey soil of Junagadh (Gujarat) to ascertain proper time of sowing (4th week of January, 2nd week of February and 4th week of February) and spacing (30 cm x 15 cm, 45 cm x 15 cm and 60 cm x 15 cm) in relation to growth and yield of guar [Cyamopsis tetragonoloba (L.) Taub.]. The results revealed that sowing in 2nd week of February enhanced growth and yield attributes viz., plant height, pods per plant and test weight and ultimately gave higher seed yield (1387 kg/ha) and stalk yield (2846 kg/ha) with higher growing degree days (GDD), helio thermal units (HTU), photo thermal units (PTU) and heat use efficiency (HUE) as well as higher net returns (` 42,051/ha) and B:C ratio (2.29) over early (4th week of January) and late (4th week of February) sowing. The results further indicated that 45 cm x 15 cm spacing promoted growth and yield attributes viz., plant height, branches per plant, pods per plant and test weight compared to 30 cm x 15 cm and 60 cm x 15 cm, which reflected in higher seed yield (1272 kg/ha) and stalk yield (2680 kg/ha) along with higher net returns (` 37,154/ha) and B:C ratio (2.03) over 30 cm x 15 cm and 60 cm x 15 cm spacing. Therefore, sowing in 2ndweek of February (when soil temperature >22.3ºC at 5 cm and >23.9ºC at 10 cm depth) and spacing of 45 cm x 15 cm could be appropriate for maximizing yield and monetary returns from summer guar under south Saurashtra agro-climatic conditions of Gujarat

The pursuit of organizational impact: hits, misses, and bouncing back

Conducting impactful research is a cornerstone of good academic practice. It increases the likelihood that research outcomes are used to generate positive change, e.g., by improving working lives, and delivering improvements in the management, operation, and performance of organizations. This, in turn, makes research relevant, representative, and credible. However, undertaking impactful research is challenging, especially when considered alongside other competing academic pressures and research goals. The purpose of this paper is to consider different approaches to creating impactful research in organizational psychology, and to propose that each approach can help meet different research goals. In particular, we introduce and reflect on the value of building long-term partnerships with organizations to create research impact, and consider lessons that we have learned from doing so. To do this, we conceptualize impact delivery as a socio-technical challenge, and demonstrate this using examples from our collaborations. We conclude with recommendations for those who seek to deliver research impact while grappling with these competing pressures