First Lattice Study of the NN-P11(1440)P_{11}(1440) Transition Form Factors

Experiments at Jefferson Laboratory, MIT-Bates, LEGS, Mainz, Bonn, GRAAL, and Spring-8 offer new opportunities to understand in detail how nucleon resonance ($N^*$) properties emerge from the nonperturbative aspects of QCD. Preliminary data from CLAS collaboration, which cover a large range of photon virtuality $Q^2$ show interesting behavior with respect to $Q^2$ dependence: in the region $Q^2 \le 1.5 {GeV}^2$, both the transverse amplitude, $A_{1/2}(Q^2)$, and the longitudinal amplitude, $S_{1/2}(Q^2)$, decrease rapidly. In this work, we attempt to use first-principles lattice QCD (for the first time) to provide a model-independent study of the Roper-nucleon transition form factor.Comment: 4 pages, 2 figures, double colum

Targeting tauopathy with engineered tau-degrading intrabodies

BACKGROUND: The accumulation of pathological tau is the main component of neurofibrillary tangles and other tau aggregates in several neurodegenerative diseases, referred to as tauopathies. Recently, immunotherapeutic approaches targeting tau have been demonstrated to be beneficial in decreasing tauopathy in animal models. We previously found that passive immunotherapy with anti-tau antibody to human tau or expression of an anti-tau secreted single-chain variable fragment (scFv) in the central nervous system of a mouse model of tauopathy decreased but did not remove all tau-associated pathology. Although these and other studies demonstrate that conventional immunotherapeutic approaches targeting tau can influence tau pathogenesis, the majority of pathological tau remains in the cytosol of cells, not typically accessible to an extracellular antibody. Therefore, we reasoned targeting intracellular tau might be more efficacious in preventing or decreasing tauopathy. METHODS: By utilizing our anti-tau scFv, we generated anti-tau intrabodies for the expression in the cytosol of neurons. To enhance the degradation capacity of conventional intrabodies, we engineered chimeric anti-tau intrabodies fused to ubiquitin harboring distinct mutations that shuttle intracellular tau for either the proteasome or lysosomal mediated degradation. To evaluate the efficacy in delaying or eliminating tauopathy, we expressed our tau degrading intrabodies or controls in human tau transgenic mice by adeno-associated virus prior to overt tau pathology and after tau deposition. RESULTS: Our results demonstrate, the expression of chimeric anti-tau intrabodies significantly reduce tau protein levels in primary neuronal cultures expression human tau relative to a non-modified anti-tau intrabody. We found the expression of engineered tau-degrading intrabodies destined for proteasomal-mediated degradation are more effective in delaying or eliminating tauopathy than a conventional intrabody in aged human tau transgenic mice. CONCLUSION: This study, harnesses the strength of intrabodies that are amendable for targeting specific domains or modifications with the cell-intrinsic mechanisms that regulate protein degradation providing a new immunotherapeutic approach with potentially improved efficacy

Strategies to reduce nutrient pollution from manure management in China

As the demand for livestock products continues to increase in China, so too does the challenge of managing increasing quantities of manure. Urgent action is needed to control point source (housing, storage and processing) and diffuse (field application) pollution and improve the utilization of manure nutrients and organic matter. Here, we review strategies to improve management at each stage of the manure management chain and at different scales. Many strategies require infrastructure investment, e.g., for containment of all manure fractions. Engineering solutions are needed to develop advanced composting systems with lower environmental footprints and design more efficient nutrient stripping technologies. At the field-scale, there is an urgent need to develop a manure nutrient recommendation system that accounts for the range of manure types, cropping systems, soils and climates throughout China. At the regional scale, coordinated planning is necessary to promote recoupling of livestock and cropping systems, and reduce nutrient accumulation in regions with little available landbank, while minimizing the risk of pollution swapping from one region to another. A range of stakeholders are needed to support the step change and innovation required to improve manure management, reduce reliance on inorganic fertilizers, and generate new business opportunities

The Equal Opportunities Commission and the Courts in Hong Kong: A Partnership Model?

Since the 1950s, the federal courts in the U.S. have developed a "new partnership" with public administrative agencies. The partnership enables the courts to play a large role in shaping public administrative decision making, implementation, other activity, and values. Severely criticized by scholars and practitioners as judicial meddling and interference with administration, the partnership model rests on the establishment of new constitutional rights for individuals in their encounters with public agencies, facilitation of suits against agencies, creation of remedial law, provision of qualified, rather than absolute, immunity in constitutional tort suits against public employees and officials, and adjustment of the level of judicial scrutiny of agencies on a continuum ranging from virtually "no look" to a "soft look" to a "hard look" depending on the administrative action involved. Our research demonstrates that some elements of the partnership model are present in Hong Kong, at least with respect to the courts and the Equal Opportunities Commission (EOC). Specifically, the courts have: 1) strengthened the statutory right to equal opportunity and the constitutional right to equality; 2) applied a hard look to administrative rationales for breaching these rights; 3) rejected "administrative difficulty" as a basis for using discriminatory gender classifications; and 4) mandated substantial institutional reform. In so doing, the courts have strengthened the EOC's ability to promote equal opportunity. This single case study adds to extant knowledge about courts and public administration and the adaptability of the partnership model to different political systems

Census of the Local Universe (CLU) Narrow-Band Survey I: Galaxy Catalogs from Preliminary Fields

We present the Census of the Local Universe (CLU) narrow-band survey to search for emission-line (\ha) galaxies. CLU-\ha~has imaged $\approx$3$\pi$ of the sky (26,470~deg$^2$) with 4 narrow-band filters that probe a distance out to 200~Mpc. We have obtained spectroscopic follow-up for galaxy candidates in 14 preliminary fields (101.6~deg$^2$) to characterize the limits and completeness of the survey. In these preliminary fields, CLU can identify emission lines down to an \ha~flux limit of $10^{-14}$~$\rm{erg~s^{-1}~cm^{-2}}$ at 90\% completeness, and recovers 83\% (67\%) of the \ha~flux from catalogued galaxies in our search volume at the $\Sigma$=2.5 ($\Sigma$=5) color excess levels. The contamination from galaxies with no emission lines is 61\% (12\%) for $\Sigma$=2.5 ($\Sigma$=5). Also, in the regions of overlap between our preliminary fields and previous emission-line surveys, we recover the majority of the galaxies found in previous surveys and identify an additional $\approx$300 galaxies. In total, we find 90 galaxies with no previous distance information, several of which are interesting objects: 7 blue compact dwarfs, 1 green pea, and a Seyfert galaxy; we also identified a known planetary nebula. These objects show that the CLU-\ha~survey can be a discovery machine for objects in our own Galaxy and extreme galaxies out to intermediate redshifts. However, the majority of the CLU-\ha~galaxies identified in this work show properties consistent with normal star-forming galaxies. CLU-\ha~galaxies with new redshifts will be added to existing galaxy catalogs to focus the search for the electromagnetic counterpart to gravitational wave events.Comment: 28 pages, 22 figures, 4 tables (Accepted to ApJ

Observation of ferromagnetism above 900 K in Cr-GaN and Cr-AlN

We report the observation of ferromagnetism at over 900K in Cr-GaN and Cr-AlN thin films. The saturation magnetization moments in our best films of Cr-GaN and Cr-AlN at low temperatures are 0.42 and 0.6 u_B/Cr atom, respectively, indicating that 14% and 20%, of the Cr atoms, respectively, are magnetically active. While Cr-AlN is highly resistive, Cr-GaN exhibits thermally activated conduction that follows the exponential law expected for variable range hopping between localized states. Hall measurements on a Cr-GaN sample indicate a mobility of 0.06 cm^2/V.s, which falls in the range characteristic of hopping conduction, and a free carrier density (1.4E20/cm^3), which is similar in magnitude to the measured magnetically-active Cr concentration (4.9E19/cm^3). A large negative magnetoresistance is attributed to scattering from loose spins associated with non-ferromagnetic impurities. The results indicate that ferromagnetism in Cr-GaN and Cr-AlN can be attributed to the double exchange mechanism as a result of hopping between near-midgap substitutional Cr impurity bands.Comment: 14 pages, 4 figures, submitted to AP

Cosmological parameters sigma_8, the baryon density, and the UV background intensity from a calibrated measurement of H I Lyman-alpha absorption at z = 1.9

We identify a concordant model for the intergalactic medium (IGM) at redshift z=1.9 that uses popular values for cosmological and astrophysical parameters and accounts for all baryons with an uncertainty of 6%. We have measured the amount of absorption, DA, in the Ly-alpha forest at redshift 1.9 in spectra of 77 QSO from the Kast spectrograph. We calibrated the continuum fits with realistic artificial spectra, and we found that averaged over all 77 QSOs the mean continuum level is within 1-2% of the correct value. Absorption from all lines in the Ly-alpha forest at z=1.9 removes DA=15.1 +/- 0.7% of the flux between 1070 and 1170 (rest) Angstroms. This is the first measurement using many QSOs at this z, and the first calibrated measurement at any redshift. Metal lines absorb 2.3 +/- 0.5%, and LLS absorb 1.0 +/- 0.4% leaving 11.8 +/- 1.0% from the lower density bulk of the IGM. Averaging over Delta z=0.1 or 154 Mpc, the dispersion is 6.1 +/- 0.3% including LLS and metal lines, or 3.9 (+0.5, -0.7)% for the lower density IGM alone, consistent with the usual description of large scale structure. LLS and metal lines are major contributors to the variation in the mean flux, and they make the flux field significantly non-Gaussian. We find that a hydrodynamic simulation on a 1024 cubed grid in a 75.7 Mpc box reproduces the observed DA from the low density IGM with parameters values H_o=71 km/s/Mpc, Omega_Lambda=0.73, Omega_m=0.27, Omega_b=0.044, sigma_8=0.9 and a UV background that has an ionization rate that is 1.08 +/- 0.08 times the prediction by Madau, Haardt & Rees (1999).Comment: Submitted to Ap

Divergent Effects of PERK and IRE1 Signaling on Cell Viability

Protein misfolding in the endoplasmic reticulum (ER) activates a set of intracellular signaling pathways, collectively termed the Unfolded Protein Response (UPR). UPR signaling promotes cell survival by reducing misfolded protein levels. If homeostasis cannot be restored, UPR signaling promotes cell death. The molecular basis for the switch between prosurvival and proapoptotic UPR function is poorly understood. The ER-resident proteins, PERK and IRE1, control two key UPR signaling pathways. Protein misfolding concomitantly activates PERK and IRE1 and has clouded insight into their contributions toward life or death cell fates. Here, we employed chemical-genetic strategies to activate individually PERK or IRE1 uncoupled from protein misfolding. We found that sustained PERK signaling impaired cell proliferation and promoted apoptosis. By contrast, equivalent durations of IRE1 signaling enhanced cell proliferation without promoting cell death. These results demonstrate that extended PERK and IRE1 signaling have opposite effects on cell viability. Differential activation of PERK and IRE1 may determine life or death decisions after ER protein misfolding

Ti/Al/Ni/Au Ohmic contacts for AlInN/AlN/GaN-based heterojunction field-effect transistors

The microstructure of AuNiAlTi/Al0.84In0.16N/AlN/GaNOhmic contacts annealed from 700 to 900 °C has been determined using transmission electron microscopy and associated analytical techniques. Intermixing and phase separation of the metal contact layers was observed to degrade the surface roughness. An optimal contact performance was obtained for contacts annealed at 800 °C and was attributed to the formation of TiN contact inclusions that had penetrated through the AlInN layers into the GaN layers underneath. These TiN contact inclusions had an inverted mushroom shape with a density of ∼108 cm−2, and they were invariably located at the positions of mixed-type threading dislocations. These inclusion defects would act as a conduction path between the metal contacts and the two-dimensional electron gas of heterojunction field-effect transistor devices. The AlInN layer remained intact in dislocation-free areas of all samples