Verifying the mass-metallicity relation in damped Lyman-alpha selected galaxies at 0.1<z<3.2

A scaling relation has recently been suggested to combine the galaxy mass-metallicity (MZ) relation with metallicities of damped Lyman-alpha systems (DLAs) in quasar spectra. Based on this relation the stellar masses of the absorbing galaxies can be predicted. We test this prediction by measuring the stellar masses of 12 galaxies in confirmed DLA absorber - galaxy pairs in the redshift range 0.1<z<3.2. We find an excellent agreement between the predicted and measured stellar masses over three orders of magnitude, and we determine the average offset $\langle C_{[M/H]} \rangle$ = 0.44+/-0.10 between absorption and emission metallicities. We further test if $C_{[M/H]}$ could depend on the impact parameter and find a correlation at the 5.5sigma level. The impact parameter dependence of the metallicity corresponds to an average metallicity difference of -0.022+/-0.004 dex/kpc. By including this metallicity vs. impact parameter correlation in the prescription instead of $C_{[M/H]}$, the scatter reduces to 0.39 dex in log M*. We provide a prescription how to calculate the stellar mass (M*,DLA) of the galaxy when both the DLA metallicity and DLA galaxy impact parameter is known. We demonstrate that DLA galaxies follow the MZ relation for luminosity-selected galaxies at z=0.7 and z=2.2 when we include a correction for the correlation between impact parameter and metallicity.Comment: 15 pages, 6 figures. Major revision. Accepted for publication in MNRA

Motion of a Vector Particle in a Curved Spacetime. II First Order Correction to a Geodesic in a Schwarzschild Background

The influence of spin on a photon's motion in a Schwarzschild and FRW spacetimes is studied. The first order correction to the geodesic motion is found. It is shown that unlike the world-lines of spinless particles, the photons world-lines do not lie in a plane.Comment: 14 pages, LaTeX2e, second paper in the series (the first one: gr-qc/0110067), replaced with typos and style corrected version, accepted in MPL

Effects of naphthalene acetic acid and calcium chloride application on nutrient uptake, growth, yield and post harvest performance of tomato fruit

Tomato plants were foliar sprayed with naphthalene acetic acid (0.02%) and calcium chloride (0.5%, 1%) individually as well as in combination to determine its effect on growth, nutrient uptake, incidence of blossom end rot, fruit yield, and enhancement of shelf life. The results showed increased absorption of calcium in tomato plants and fruits, which were treated with NAA in combination with CaCl2. Higher level of CACl2 (1%) with NAA (0.02%) increased plant growth and yield by improving mineral uptake of tomato plants. The improved calcium absorption also resulted in lowering occurrence of blossom end rot in tomato fruits. In addition, it was also observed that during storage at ambient conditions (20-25 °C) for sixteen days, tomato fruits maintained best quality for longer period of time when treated with calcium chloride (1%) along with naphthalene acetic acid (0.02%) as compared to other treatments. Although, fruit quality was lowered with passage of storage time but tomato fruits from treated plants maintained their quality for longer duration as compared to control

Massive, Absorption-selected Galaxies at Intermediate Redshifts

The nature of absorption-selected galaxies and their connection to the general galaxy population have been open issues for more than three decades, with little information available on their gas properties. Here we show, using detections of carbon monoxide (CO) emission with the Atacama Large Millimeter/submillimeter Array (ALMA), that five of seven high-metallicity, absorption-selected galaxies at intermediate redshifts, $z \approx 0.5-0.8$, have large molecular gas masses, $M_{\rm Mol} \approx (0.6 - 8.2) \times 10^{10} \: {\rm M}_\odot$ and high molecular gas fractions ($f_{\rm Mol} \equiv \: M_{\rm Mol}/(M_\ast + M_{\rm Mol}) \approx 0.29-0.87)$. Their modest star formation rates (SFRs), $\approx (0.3-9.5) \: {\rm M}_\odot$ yr$^{-1}$, then imply long gas depletion timescales, $\approx (3 - 120)$ Gyr. The high-metallicity absorption-selected galaxies at $z \approx 0.5-0.8$ appear distinct from populations of star-forming galaxies at both $z \approx 1.3-2.5$, during the peak of star formation activity in the Universe, and lower redshifts, $z \lesssim 0.05$. Their relatively low SFRs, despite the large molecular gas reservoirs, may indicate a transition in the nature of star formation at intermediate redshifts, $z \approx 0.7$.Comment: 8 pages, 3 figures; accepted for publication in Astrophysical Journal Letters. Minor changes to match the version in press in ApJ

Sirolimus attenuates disease progression in an orthologous mouse model of human autosomal dominant polycystic kidney disease

In autosomal dominant polycystic kidney disease (ADPKD), abnormal proliferation of tubular cells drives cyst development and growth. Sirolimus, an inhibitor of the protein kinase mammalian target of rapamycin (mTOR) and a potent anti-proliferative agent, decreases cyst growth in several genetically distinct rodent models of polycystic kidney disease (PKD). We determined here the effect of sirolimus on renal cyst growth in Pkd2WS25/− mice; an ortholog of human ADPKD involving mutation of the Pkd2 gene. In Pkd2WS25/− mice treated with sirolimus, both the two kidney/total body weight (2K/TBW) ratio and the cyst volume density (CVD) were significantly decreased by over half compared with untreated mice suffering with PKD. However, there was no effect on the increased blood urea nitrogen (BUN) levels as an index of kidney function. There are two distinct complexes containing mTOR depending on its binding partners: mTORC1 and mTORC2. Western blot analysis of whole kidney lysates and immunohistochemistry of the cysts found that phospho-S6 ribosomal protein, a marker of mTORC1 activity, was increased in Pkd2WS25/− mice and its phosphorylation was decreased by sirolimus treatment. Phospho-Akt at serine 473, a marker associated with mTORC2 activity, was not different between Pkd2WS25/− mice and normal littermate controls. Hence, our study found that inhibition of mTORC1 by sirolimus correlated with decreased renal cyst growth in this model of human ADPKD but had no effect on the decline in renal function

The Achievable Rate of Interweave Cognitive Radio in the Face of Sensing Errors

Cognitive radio (CR) systems are potentially capable of mitigating the spectrum shortage of contemporary wireless systems. In this paper, we provide a brief overview of CR systems and the important research milestones of their evolution, along with their standardization activities, as a result of their research. This is followed by the detailed analysis of the interweave policy-based CR network (CRN) and by a detailed comparison with the family of underlay-based CRNs. In the interweave-based CRN, sensing of the primary user's (PU) spectrum by the secondary user's (SU) has remained a challenge, because the sensing errors prevent us from fulfilling the significant throughput gains that the concept of CR promises. Since missed detection and false alarm errors in real-time spectrum sensing cannot be avoided, based on a new approach, we quantify the achievable rates of the interweave CR by explicitly incorporating the effect of sensing errors. The link between the PU transmitter and the SU transmitter is assumed to be fast fading. Explicitly, the achievable rate degradation imposed by the sensing errors is analyzed for two spectrum sensing techniques, namely, for energy detection and for magnitude squared coherence-based detection. It is demonstrated that when the channel is sparsely occupied by the PU, the reusing techniques that are capable of simultaneously providing low missed detection and false alarm probabilities cause only a minor degradation to the achievable rates. Furthermore, based on the achievable rates derived for underlay CRNs, we compare the interweave CR and the underlay CR paradigms from the perspective of their resilience against spectrum sensing errors. Interestingly, in many practical regimes, the interweave CR paradigm outperforms the underlay CR paradigm in the presence of sensing errors, especially when the SNR at the SU is below 10 dB and when the SNR at the PU is in the range of 10-40 dB. Furthermore, we also provide rules of thumb that identify regimes, where the interweave CR outperforms the underlay CR

Combination of Co3O4 deposited rGO hybrid nanofluids and longitudinal strip inserts: thermal properties, heat transfer, friction factor, and thermal performance evaluations

The reduced-graphene oxide/cobalt oxide hybrid nanoparticles were prepared based on the in-situ/chemical co-precipitation technique, and they were analyzed by transmission electron microscope, x-ray diffraction, and magnetometer techniques. The hybrid nanofluids were prepared with particle loadings of 0.05%, 0.1%, and 0.2% by dispersing synthesized reduced-graphene oxide/cobalt oxide in distilled water and their physical properties were measured. The thermal performance of the nanofluids was studied, when they flow in the turbulent regime through a circular tube. The thermal performance was also evaluated when straight (longitudinal) strip inserts with aspect ratios of 1, 2, and 4, were used inside the circular. These straight strip inserts by increasing the flow turbulence intensity act as turbulators. Results indicate that with a dilution of 0.2% concentration of hybrid nanoparticles in water, the Nusselt number is enhanced by 25.65%, and it is further enhanced by 110.56% with a straight strip insert of aspect ratio 1. The use of hybrid nanofluids and straight strip inserts leads to a slight penalty in fluid friction. For 0.2% concentration of hybrid nanoparticles in water, the penalty in friction factor is 11%, and it is further increased to 69.8% with 0.2% particle loadings and a straight strip insert of aspect ratio1. Moreover, the thermal performance factor of hybrid nanofluids with and without straight strip inserts presents values higher than 1, which shows the benefit of the prepared hybrid nanofluids in a turbulent flow. A general form of regression equations are developed based on the experimental data.publishe

The future of cardiovascular stents: bioresorbable and integrated biosensor technology

Cardiovascular disease is the greatest cause of death worldwide. Atherosclerosis is the underlying pathology responsible for two thirds of these deaths. It is the age‐dependent process of “furring of the arteries.” In many scenarios the disease is caused by poor diet, high blood pressure, and genetic risk factors, and is exacerbated by obesity, diabetes, and sedentary lifestyle. Current pharmacological anti‐atherosclerotic modalities still fail to control the disease and improvements in clinical interventions are urgently required. Blocked atherosclerotic arteries are routinely treated in hospitals with an expandable metal stent. However, stented vessels are often silently re‐blocked by developing “in‐stent restenosis,” a wound response, in which the vessel's lumen renarrows by excess proliferation of vascular smooth muscle cells, termed hyperplasia. Herein, the current stent technology and the future of biosensing devices to overcome in‐stent restenosis are reviewed. Second, with advances in nanofabrication, new sensing methods and how researchers are investigating ways to integrate biosensors within stents are highlighted. The future of implantable medical devices in the context of the emerging “Internet of Things” and how this will significantly influence future biosensor technology for future generations are also discussed