THE ACTION SPECTRUM FOR INDUCTION OF CHRONIC ACTINIC DERMATITIS IS SIMILAR TO THAT FOR SUNBURN INFLAMMATION

The action spectrum for induction of the abnormal cutaneous response at 24 h in the photosensitivity disorder chronic actinic dermatitis (CAD) was determined in 15 patients and found to be the same in shape as that for normal sunburn in fair-skinned individuals at 24 h, as determined for 47 control volunteers, although displaced in magnitude. This suggests that an endogenous chromophore(s), the same as or similar to that/those responsible for human sunburn, may be responsible for initiation of the abnormal reaction to irradiation in CAD, and that the putative antigen associated with the CAD reaction may be derived from that/those or associated molecules.     

Remarks on Maximal Operators Over Arbitrary Sets of Directions

Throughout this paper, we shall let be a subset of [0, 1] havingcardinality N. We shall consider to be a set of slopes, andfor any s , we shall let e_s be the unit vector of slope s inR². Then, following [7], we define the maximal operator on R²associated with the set by The history of the bounds obtained on is quite curious. The earliest study of relatedoperators was carried out by Cordoba [2]. He obtained a boundof C(1 + log N) on the L² operator norm of the Kakeya maximaloperator over rectangles of length 1 and eccentricity N. Thisoperator is analogous to with However, for arbitrary sets, the best known result seems to be C(1 + log N). This followsfrom Lemma 5.1 in [1], but a point of view which produces aproof appears already in [8]. However, in this paper, we provethe following.     

New levels observed in188Os from the decay of188Re

The level structure of¹⁸⁸Os has been investigated following the decay of 17h¹⁸⁸Re. The energies and relative intensities of 41 gamma rays were determined using large volume high resolution Ge(Li) detectors. The decay was observed to populate the 0⁺ states at 1478 and 1704 keV which were recently observed in (p, t) reaction studies. Additional states at 1414 and 1843 keV were also observed in the decay.     

A sum-product estimate in finite fields,and applications

Let A be a subset of a finite field for some prime q. If for some > 0, then we prove the estimate for some = () > 0. This is a finite field analogue of a result of [ErS]. We then use this estimate to prove a Szemerédi-Trotter type theorem in finite fields, and obtain a new estimate for the Erdös distance problem in finite fields, as well as the three-dimensional Kakeya problem in finite fields.     

Real‐Time Interrogation of Aspirin Reactivity,Biochemistry, and Biodistribution by Hyperpolarized Magnetic Resonance Spectroscopy

Hyperpolarized magnetic resonance spectroscopy enables quantitative, non‐radioactive, real‐time measurement of imaging probe biodistribution and metabolism in vivo. Here, we investigate and report on the development and characterization of hyperpolarized acetylsalicylic acid (aspirin) and its use as a nuclear magnetic resonance (NMR) probe. Aspirin derivatives were synthesized with single‐ and double‐¹³C labels and hyperpolarized by dynamic nuclear polarization with 4.7 % and 3 % polarization, respectively. The longitudinal relaxation constants (T₁) for the labeled acetyl and carboxyl carbonyls were approximately 30 seconds, supporting in vivo imaging and spectroscopy applications. In vitro hydrolysis, transacetylation, and albumin binding of hyperpolarized aspirin were readily monitored in real time by ¹³C‐NMR spectroscopy. Hyperpolarized, double‐labeled aspirin was well tolerated in mice and could be observed by both ¹³C‐MR imaging and ¹³C‐NMR spectroscopy in vivo.     

Real‐Time Interrogation of Aspirin Reactivity,Biochemistry, and Biodistribution by Hyperpolarized Magnetic Resonance Spectroscopy

Hyperpolarized magnetic resonance spectroscopy enables quantitative, non‐radioactive, real‐time measurement of imaging probe biodistribution and metabolism in vivo. Here, we investigate and report on the development and characterization of hyperpolarized acetylsalicylic acid (aspirin) and its use as a nuclear magnetic resonance (NMR) probe. Aspirin derivatives were synthesized with single‐ and double‐¹³C labels and hyperpolarized by dynamic nuclear polarization with 4.7 % and 3 % polarization, respectively. The longitudinal relaxation constants (T₁) for the labeled acetyl and carboxyl carbonyls were approximately 30 seconds, supporting in vivo imaging and spectroscopy applications. In vitro hydrolysis, transacetylation, and albumin binding of hyperpolarized aspirin were readily monitored in real time by ¹³C‐NMR spectroscopy. Hyperpolarized, double‐labeled aspirin was well tolerated in mice and could be observed by both ¹³C‐MR imaging and ¹³C‐NMR spectroscopy in vivo.     

Pseudodifferential operators on<Emphasis Type="Italic">SU</Emphasis>(2)

We construct an algebra of left-invariant pseudodifferential operators on SU(2). We require only that the symbols be homogeneous and C². For Fourier-bandlimited symbols, we derive the expected formulae for composition and commutators and construct an orthonormal basis of common approximate eigenvectors that could be used to study spectral theory. Some remarks on applications to matrices of operators are made.