Deep inelastic scattering from A=3 nuclei and the neutron structure function

We present a comprehensive analysis of deep inelastic scattering from He-3 and H-3, focusing in particular on the extraction of the free neutron structure function, F_2^n. Nuclear corrections are shown to cancel to within 1-2% for the isospin-weighted ratio of He-3 to H-3 structure functions, which leads to more than an order of magnitude improvement in the current uncertainty on the neutron to proton ratio F_2^n/F_2^p at large x. Theoretical uncertainties originating from the nuclear wave function, including possible non-nucleonic components, are evaluated. Measurement of the He-3 and H-3 structure functions will, in addition, determine the magnitude of the EMC effect in all A < 4 nuclei.Comment: 40 pages, 12 figures, to appear in Phys. Rev.

Gauge-invariant theory of pion photoproduction with dressed hadrons

Based on an effective field theory of hadrons in which quantum chromodynamics is assumed to provide the necessary bare cutoff functions, a gauge-invariant theory of pion photoproduction with fully dressed nucleons is developed. The formalism provides consistent dynamical descriptions of pi-N --> pi-N scattering and Gamma-N --> pi-N production mechanisms in terms of nonlinear integral equations for fully dressed hadrons. Defining electromagnetic currents via the gauging of hadronic n-point Green's functions, dynamically detailed currents for dressed nucleons are introduced. The dressed hadron currents and the pion photoproduction current are explicitly shown to satisfy gauge invariance in a self-consistent manner. Approximations are discussed that make the nonlinear formalism manageable in practice and yet preserve gauge invariance. This is achieved by recasting the gauge conditions for all contributing interaction currents as continuity equations with ``surface'' terms for the individual particle legs coming into or going out of the hadronic interaction region. General procedures are given that approximate any type of (global) interaction current in a gauge-invariance preserving manner as a sum of single-particle ``surface'' currents. It is argued that these prescriptions carry over to other reactions, irrespective of the number or type of contributing hadrons or hadronic systems.Comment: 33 pages, RevTeX; includes 8 postscript figures (requires psfig.sty). This version corrects some minor errors, etc.; contains updated references. Accepted for publication in Phys. Rev. C56 (Oct. 97

Effect of Sodium-Glucose Cotransporter-2 Inhibitors on Endothelial Function: A Systematic Review of Preclinical Studies

IntroductionWhile the beneficial effects of sodium-glucose cotransporter-2 (SGLT-2) inhibitors on cardiovascular and renal outcomes are recognized, their direct effects on endothelial function remain unclear. We, therefore, undertook a systematic review to evaluate the current literature in this area.MethodsElectronic databases (PubMed, EMBASE, and Medline) were systematically searched using PRISMA guidelines for studies involving the in vitro, in vivo, or ex vivo administration of SGLT-2 inhibitors to animals, vascular tissue, or vascular endothelial cells.ResultsOf 144 retrieved publications, 24 experimental studies met the inclusion criteria. Reporting of possible sources of bias were poor, making the overall risk of bias difficult to assess. Within the 24 studies, the SGLT-2 inhibitors canagliflozin, ipragliflozin, empagliflozin, dapagliflozin, tofogliflozin, and luseogliflozin were assessed as interventions. Animal model studies (n = 17) demonstrated that all SGLT-2 inhibitors prevented endothelial dysfunction and enhanced endothelium-dependent vasorelaxation in diabetic and non-diabetic models. In vitro studies (n = 9) using human endothelial cells indicated a direct anti-inflammatory effect of dapagliflozin (1–100 nM) and canagliflozin, (10 µM), while empagliflozin (1 and 10 µM) improved viability of hyperglycemic cells. Potential mechanisms of action of the SGLT-2 inhibitors include a reduction in oxidative stress, modulation of adhesion molecules and reductions in pro-inflammatory cytokines.ConclusionsPreclinical studies indicate that SGLT-2 inhibitors attenuate vascular dysfunction in preclinical models via a combination of mechanisms that appear to act independently of glucose-lowering benefits

A Gauge Invariant Unitary Theory for Pion Photoproduction

A covariant, unitary and gauge invariant theory for pion photoproduction on a single nucleon is presented. To achieve gauge invariance at the operator level one needs to include both the $\pi N$ and $\gamma\pi N$ thresholds. The final amplitude can be written in terms of a distorted wave in the final $\pi N$ channel provided one includes additional diagrams to the standard Born term in which the photon is coupled to the final state pion and nucleon. These additional diagrams are required in order to satisfy gauge invariance.Comment: 4 pages, LaTeX, 1 figure as a separate uuencoded compressed tar fil

Stress Indicator, Carcass Composition, and Meat Cholesterol of Kampung-Broiler Crossbred Chicken Treated by Different Stocking Density

This study aimed to investigate the effect of stocking density on stress indicator, carcass composition, and meat cholesterol content of kampung–broiler crossbred chicken. Anamount of 90 DOCs of crossbred kampung-broiler (KB) were placed into 9 plots sized 1x1 m2 in semi closed house that consist of 3 stocking densities 8, 10 and 12 birds m-2 and respectively 3 replicates. The chickens were fed commercial broiler feed. Approximately ± 30% roosters slaughtered for analysis of malondialdehyde, carcass quality, and meat cholesterol. Malondialdehyde, carcass composition, and meat cholesterol was completely randomized designed with different stocking densities treatments and three replicates. Data was analyzed using analysis of variance (ANOVA) and had previously been tested for requirement of variance test assumption. Data of temperature humidity index (THI) was descriptively explained. The results showed that the effect of different stocking densities on stress indicator reflected by THI value and MDA content, carcass composition (percentage of carcass and abdominal fat weight), and cholesterol level were not significant. The different of stocking densities (8, 10 and 12 birds m-2) did not affect the stress indicators reflected by THI and MDA level, carcass composition and meat cholesterol level. Kampung-broiler crossbred chicken could develop at 8, 10 or 12 birds m-2 densities since the lower of abdominal fat and meat cholesterol were resulte

Ξ−d→nΛΛ\Xi^{-} d\to n\Lambda\Lambda and the ΛΛ\Lambda\Lambda final state interaction

The reaction $\Xi^-d\to n\Lambda\Lambda$ is studied within the framework of the Faddeev equations as a possible tool to gain insight into the final state $\Lambda$--$\Lambda$ interaction. The neutron differential energy spectrum gives a final state interaction that is sensitive to both the $\Lambda$--$\Lambda$ amplitude at threshold, and the coupling between the $\Lambda$--$\Lambda$ and $\Xi$--$N$ channels. The latter is a result of interference between two mechanisms for the production of the final state, which suggests that this reaction could give a measure of flavor SU(3) violation in the two-baryon system.Comment: 24 pages, 8 figures, submitted to Physical Reviw

Structure functions for the three nucleon system

The spectral functions and light-cone momentum distributions of protons and neutrons in 3He and 3H are given in terms of the three-nucleon wave function for realistic nucleon-nucleon interactions. To reduce computational complexity, separable expansions are employed for the nucleon-nucleon potentials. The results for the light-cone momentum distributions suggest that they are not very sensitive to the details of the two-body interaction, as long as it has reasonable short-range repulsion. The unpolarised and polarised structure functions are examined for both 3He and 3H in order to test the usefulness of 3He as a neutron target. It is found that the measurement of the spin structure function of polarised 3H would provide a very clear test of the predicted change in the polarised parton distributions of a bound proton.Comment: 30 pages, REVTeX, 11 figure

Produksi Telur Ayam Persilangan Merawang dengan Arab

The egg production of local chiken can be increased by crossing of arab and merawang chicken. This study aimed to observed egg production performances of crossing between merawang x merawangarab (M-MA), merawangarab x merawang (MA-M), merawangarab x merawangarab (MA-MA), arabmerawang x arabmerawang (AM-AM), merawangarab x arab (MA-A), and arab x merawangarab (A-MA). Parameters in this study were egg weight, egg shape index, hen day production and feed conversion. The result showed that the egg weight of MA-M chicken was significantly greater (P&lt;0.05). than M-MA, MA-MA, AM-AM, MA-A, and A-MA chicken. The MA-A egg index was significantly larger (P&lt;0.05) than other crossing. Hen day production of M-MA chicken was significantly greater (P&lt;0.05) and feed convertion was significantly efficient (P&lt;0.05) than other crossing. MA hens had better production than other hens

Formulation and Evaluation of Topically Retained Hydrogels Loaded with Timolol Maleate Microspheres for Extended Release in Treating Glaucoma

Conventional aqueous eye drop formulations have a shorter retention period and wash out of the precorneal region more easily. In this study, biodegradable microsphere-loaded hydrogels were developed to extend the time of residence and improve the drug bioavailability. The prepared microspheres were fabricated using PLGA as the biodegradable polymer and PVA as the surfactant. Hydrogels were prepared using Carbopol 940 and Gellan gum as gelling agents. Methods: The microspheres were created through a technique known as double emulsion solvent evaporation method. Evaluation included for its percentage yield, entrapment efficiency, particle size and surface morphology of the prepared microspheres. Timolol Maleate microsphere loaded hydrogel underwent assessments for pH, spreadability, rheological behaviour, sterility, antimicrobial efficacy, in vitro release studies, drug release kinetics and ocular irritation. Results: FTIR analysis confirmed compatibility between the drug and polymer. SEM observations indicated spherical microspheres with sizes ranging from 1 to 12 µm, suitable for ocular application. All formulations exhibited pH values between 4.2 and 5.0, with gelation occurring at 35°C to 38°C. Formulation F3 demonstrated optimal viscosity (1486 – 1850 cps) and good spreadability. Sterility tests were successful, and F3 displayed a drug release of 82.6% after 24 hours. Antimicrobial studies exhibited inhibition zones, and ocular tests on rabbits revealed no irritation. Stability analysis indicated no significant changes in pH or clarity. Conclusion: Based on physiological, rheological, and in vitro evaluations F3 was identified as the most suitable formulation for extended Timolol Maleate release via hydrogel, holding promise for effective glaucoma treatment

The reaction pi N to pi pi N in a meson-exchange approach

A resonance model for two-pion production in the pion-nucleon reaction is developed that includes information obtained in the analysis of pion-nucleon scattering in a meson-exchange model. The baryonic resonances Delta(1232), N*(1440), N*(1520), N*(1535), and N*(1650) are included. The model reproduces the total cross sections up to kinetic energies of the incident pion of 350 MeV and obtains the shapes of the differential cross sections in reasonable agreement with the data.Comment: 7 pages, 7 figures, 2 table