What Impulse Response Do Instrumental Variables Identify?

Macro shocks are often composites, yet overlooked in the impulse response analysis. When an instrumental variable (IV) is used to identify a composite shock, it violates the common IV exclusion restriction. We show that the Local Projection-IV estimand is represented as a weighted average of component-wise impulse responses but with possibly negative weights, which occur when the IV and shock components have opposite correlations. We further develop alternative (set-) identification strategies for the LP-IV based on sign restrictions or additional granular information. Our applications confirm the composite nature of monetary policy shocks and reveal a non-defense spending multiplier exceeding one

Optical Spectroscopy of Supernova Remnants in M81 and M82

We present spectroscopy of 28 SNR candidates as well as one H II region in M81, and two SNR candidates in M82. Twenty six out of the M81 candidates turn out to be genuine SNRs, and two in M82 may be shocked condensations in the galactic outflow or SNRs. The distribution of [N II]/H{\alpha} ratios of M81 SNRs is bimodal. M81 SNRs are divided into two groups in the spectral line ratio diagrams: an [O III]-strong group and an [O III]-weak group. The latter have larger sizes, and may have faster shock velocity. [N II]/H{\alpha} ratios of the SNRs show a strong correlation with [S II]/H{\alpha} ratios. They show a clear radial gradient in [N II]/H{\alpha} and [S II]/H{\alpha} ratios: dLog ([N II]/H{\alpha})/dLog R = -0.018 {\pm} 0.008 dex/kpc and dLog ([S II]/H{\alpha})/dLog R = -0.016 {\pm} 0.008 dex/kpc where R is a deprojected galactocentric distance. We estimate the nitrogen and oxygen abundance of the SNRs from the comparison with shock-ionization models. We obtain a value for the nitrogen radial gradient, dLog(N/H)/dLogR = -0.023 {\pm} 0.009 dex/kpc, and little evidence for the gradient in oxygen. This nitrogen abundance shows a few times flatter gradient than those of the planetary nebulae and H II regions. We find that five SNRs are matched with X-ray sources. Their X-ray hardness colors are consistent with thermal SNRs.Comment: 19 pages, 24 figures, 5 tables, ApJ accepte

Favored serum albumin level and ICF volume after use of 1.1% aminoacid based peritoneal dialysis(PD) solution

Aminoacid based PD solution (AAD) has been shown to induce positive nitrogen balance and improve nutritional markers of malnourished patients. But its effcets on body fluid composition and various nutritional markers are contradictory. Nutritional markers may influenced by patient's ECF volume status. So we evaluate effects of AAD on nutritional markers and body composition by analysis using multi-frequency bioimpedance analyzer. 35 PD patients(>6months duration of CAPD) were prospectively randomized to 17 AAD(Nutrineal, one time use/day) and 18 GD group(keep their glucose based PD solution). After 3 months follow up, AAD group showed marginally increased body weight and fat mass, decreased ECF volume(12.45±0.54Lvs 12.10±0.57L, p=0.06), no changed ICF volume(22.2±0.9Lvs 22.3±0.9L, p>0.05) and marginally increased drainage volume(8.77±0.76Lvs 9.12±0.83L, p=0.09). AAD group also showed favored several markers include nPCR(1.59±0.07vs 1.98±0.08, p=0.00), BUN and albumin level (3.54±0.11 vs 3.74±0.11, p=0.02). Although serum albumin level was increased, correction with ECF volume(albumin level X ECF volume) makes it no difference (43.45±2.13vs 44.80±2.28, p=0.14). Furthermore △albumin vs △ECF showed negative correlation pattern(r=-0.46, p=0.07) that means serum albumin change was influenced by ECF volume change. In conclusion, AAD treatment improved markers of better nutritional status. However the change in serum albumin level was influenced by patient's ECF volume status, which can partially explain contradictory effect of aminoacid based PD solution on serum albumin level

AKARI Detection of the Infrared-Bright Supernova Remnant B0104-72.3 in the Small Magellanic Cloud

We present a serendipitous detection of the infrared-bright supernova remnant (SNR) B0104-72.3 in the Small Magellanic Cloud by the Infrared Camera (IRC) onboard AKARI. An elongated, partially complete shell is detected in all four observed IRC bands covering 2.6-15 um. The infrared shell surrounds radio, optical, and X-ray emission associated with the SNR and is probably a radiative SNR shell. This is the first detection of a SNR shell in this near/mid-infrared waveband in the Small Magellanic Cloud. The IRC color indicates that the infrared emission might be from shocked H2 molecules with some possible contributions from ionic lines. We conclude that B0104-72.3 is a middle-aged SNR interacting with molecular clouds, similar to the Galactic SNR IC 443. Our results highlight the potential of AKARI IRC observations in studying SNRs, especially for diagnosing SNR shocks.Comment: 12 pages with 3 figures, accepted for publication in AKARI PASJ special issu