2,275 research outputs found
A new Australian species of Luffa (Cucurbitaceae) and typification of two Australian Cucumis names, all based on specimens collected by Ferdinand Mueller in 1856
As a result of his botanical explorations in northern Australia, Ferdinand von Mueller named several Cucurbitaceae that molecular data now show to be distinct, requiring their resurrection from unjustified synonymy. We here describe and illustrate Luffa saccata F. Muell. ex I.Telford, validating a manuscript name listed under L. graveolens Roxb. since 1859, and we lectotypify Cucumis picrocarpus F. Muell. and C. jucundus F. Muell. The lectotype of the name C. jucundus, a synonym of C. melo, is mounted on the same sheet as the lectotype of C. picrocarpus, which is the sister species of the cultivated C. melo as shown in a recent publication
Pultenaea williamsii (Fabaceae: Mirbelieae), a new species endemic to the New England Tableland Bioregion of New South Wales
Pultenaea williamsii I.Telford, Clugston & R.L.Barrett (Fabaceae, Faboideae, Mirbelieae), endemic to the New England Bioregion, New South Wales, Australia, is described as new, segregated from the P. flexilis–P. juniperina–P. blakelyi species assemblage. Its distribution is mapped, and habitat and conservation status discussed
Changes in rod and frame test scores recorded in schoolchildren during development--a longitudinal study.
The Rod and Frame Test has been used to assess the degree to which subjects rely on the visual frame of reference to perceive vertical (visual field dependence-independence perceptual style). Early investigations found children exhibited a wide range of alignment errors, which reduced as they matured. These studies used a mechanical Rod and Frame system, and presented only mean values of grouped data. The current study also considered changes in individual performance. Changes in rod alignment accuracy in 419 school children were measured using a computer-based Rod and Frame test. Each child was tested at school Grade 2 and retested in Grades 4 and 6. The results confirmed that children displayed a wide range of alignment errors, which decreased with age but did not reach the expected adult values. Although most children showed a decrease in frame dependency over the 4 years of the study, almost 20% had increased alignment errors suggesting that they were becoming more frame-dependent. Plots of individual variation (SD) against mean error allowed the sample to be divided into 4 groups; the majority with small errors and SDs; a group with small SDs, but alignments clustering around the frame angle of 18°; a group showing large errors in the opposite direction to the frame tilt; and a small number with large SDs whose alignment appeared to be random. The errors in the last 3 groups could largely be explained by alignment of the rod to different aspects of the frame. At corresponding ages females exhibited larger alignment errors than males although this did not reach statistical significance. This study confirms that children rely more heavily on the visual frame of reference for processing spatial orientation cues. Most become less frame-dependent as they mature, but there are considerable individual differences
Layered Antiferromagnetism Induces Large Negative Magnetoresistance in the van der Waals Semiconductor CrSBr
The recent discovery of magnetism within the family of exfoliatable van der
Waals (vdW) compounds has attracted considerable interest in these materials
for both fundamental research and technological applications. However current
vdW magnets are limited by their extreme sensitivity to air, low ordering
temperatures, and poor charge transport properties. Here we report the magnetic
and electronic properties of CrSBr, an air-stable vdW antiferromagnetic
semiconductor that readily cleaves perpendicular to the stacking axis. Below
its N\'{e}el temperature, K, CrSBr adopts an A-type
antiferromagnetic structure with each individual layer ferromagnetically
ordered internally and the layers coupled antiferromagnetically along the
stacking direction. Scanning tunneling spectroscopy and photoluminescence (PL)
reveal that the electronic gap is eV with a
corresponding PL peak centered at eV. Using magnetotransport
measurements, we demonstrate strong coupling between magnetic order and
transport properties in CrSBr, leading to a large negative magnetoresistance
response that is unique amongst vdW materials. These findings establish CrSBr
as a promising material platform for increasing the applicability of vdW
magnets to the field of spin-based electronics
Rapamycin delays growth of Wnt-1 tumors in spite of suppression of host immunity
<p>Abstract</p> <p>Background</p> <p>Rapamycin, an inhibitor of mammalian target of Rapamycin (mTOR), is an immunosuppressive agent that has anti-proliferative effects on some tumors. However, the role of Rapamycin-induced immune suppression on tumor progression has not been examined.</p> <p>Methods</p> <p>We developed a transplantation model for generation of mammary tumors in syngeneic recipients that can be used to address the role of the immune system on tumor progression. We examined the effect of Rapamycin on the immune system and growth of MMTV-driven Wnt-1 mammary tumors which were transplanted into irradiated and bone marrow-reconstituted, or naïve mice.</p> <p>Results</p> <p>Rapamycin induced severe immunosuppression and significantly delayed the growth of Wnt-1 tumors. T cell depletion in spleen and thymus and reduction in T cell cytokine secretion were evident within 7 days of therapy. By day 20, splenic but not thymic T cell counts, and cytokine secretion recovered. We determined whether adoptive T cell therapy enhances the anti-cancer effect using <it>ex vivo </it>generated Rapamycin-resistant T cells. However, T cell transfer during Rapamycin therapy did not improve the outcome relative to drug therapy alone. Thus, we could not confirm that suppression of T cell immunity contributes to tumor growth in this model. Consistent with suppression of the mTOR pathway, decreased 4E-BP1, p70 S6-kinase, and S6 protein phosphorylation correlated with a decrease in Wnt-1 tumor cell proliferation.</p> <p>Conclusion</p> <p>Rapamycin has a direct anti-tumor effect on Wnt-1 breast cancer <it>in vivo </it>that involves inhibition of the mTOR pathway at doses that also suppress host immune responses.</p
3D printing of medicines: Engineering novel oral devices with unique design and drug release characteristics
YesThree dimensional printing (3DP) was used to engineer novel oral drug delivery devices, with
specialised design configurations loaded with multiple actives, with applications in personalised
medicine. A filament extruder was used to obtain drug-loaded - paracetamol (acetaminophen) or
caffeine - filaments of polyvinyl alcohol with characteristics suitable for use in fused-deposition
modelling 3D printing. A multi-nozzle 3D printer enabled fabrication of capsule-shaped solid
devices, containing paracetamol and caffeine, with different internal structures. The design
configurations included a multilayer device, with each layer containing drug, whose identity was
different from the drug in the adjacent layers; and a two-compartment device comprising a
caplet embedded within a larger caplet (DuoCaplet), with each compartment containing a
different drug. Raman spectroscopy was used to collect 2-dimensional hyper spectral arrays
across the entire surface of the devices. Processing of the arrays using direct classical least
squares component matching to produce false colour representations of distribution of the drugs
showed clearly the areas that contain paracetamol and caffeine, and that there is a definitive
separation between the drug layers.
Drug release tests in biorelevant media showed unique drug release profiles dependent on the
macrostructure of the devices. In the case of the multilayer devices, release of both drugs was
simultaneous and independent of drug solubility. With the DuoCaplet design it was possible to
engineer either rapid drug release or delayed release by selecting the site of incorporation of the
drug in the device, and the lag-time for release from the internal compartment was dependent
on the characteristics of the external layer. The study confirms the potential of 3D printing to
fabricate multiple-drug containing devices with specialized design configurations and unique
drug release characteristics, which would not otherwise be possible using conventional
manufacturing methods.The full-text of this article will be released for public view at the end of the publisher embargo on 10 Oct 2016
- …