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Guidelines are offered to help school carpet buyers avoid disappointments and costly selection mistakes. (Author)

The chemically very different minerals aenigmatite and sapphirine are crystallographically closely related, being ordered members of isomorphous families of OD structures consisting of equivalent layers. The symbol of the OD-groupoid family characterizing their symmetry is P1(2/n)l {1(22/c1/2)1 }. Formulae for the structure factor are deduced for the general member of the family and then specialized to explain the diffraction pattern of some members of interest. The twinned structures of aenigmatite, rhonite and krinovite are explained as OD twins; the constituting twin individuals are structures of maximum degree of order corresponding to the OD-groupoid family quoted above.

1. We have tested the hypothesis that insulin might decrease the levels of cyclic AMP (cAMP) in rat epididymal adipose tissue by stimulating the activity of a cAMP phosphodiesterase. 2. Dibutyryl cyclic AMP (DBcAMP) was comparable to cAMP as a substrate for cAMP phosphodiesterase of adipose tissue; the hydrolysis of both cylic nucleotides was inhibited by theophylline. 3. DBcAMP, but not cAMP, was strongly lipolytic in free adipose cells; this activity was unaffected by insulin in vitro at concentrations of the hormone sufficient to be strongly antilipolytic against epinephrine. DBcAMP-stimulated lipolysis was inhibited by nicotinic acid, a stimulator of cAMP phosphodiesterase. 4. Lipolytic concentrations of theophylline and caffeine synergistically stimulated the lipolytic effect of DBcAMP in free adipose cells at all but saturating levels of DBcAMP. Lower, nonlipolytic concentrations of the methyl xanthines also stimulated the lipolytic activity of DBcAMP, and this synergism was reversed by insulin, but only at low concentrations of the cyclic nucleotide. 5. Neither prior treatment of fat pads with insulin nor the presence of insulin during enzyme assay affected the cAMP phosphodiesterase activities of 2000 x g sediment and supernatant fractions. 6. Neither hypo- nor hyperinsulinism in donor rats influenced the cAMP phosphodiesterase activity of adipose tissue.

It is well known to students of the Italian Renaissance that the regained supremacy of the vernacular in the latter half of the fifteenth century, first in Tuscany and then in other parts of the peninsula, did much to stimulate the revival in the study of Dante. The haughty contempt, implicit or explicit, that many of the early humanists felt for the Divina Commedia then gave way to enthusiastic efforts at text interpretation and æsthetic appreciation on the part of poets, artists, and scholars. Nor was this renewed interest in Dante confined to Italy; indeed, the Divina Commedia was much studied even beyond the Alps, where it was edited and translated several times.

An atypical case of an early periosteal chondroma involving the distal phalanx of a great toe without affecting the contiguous cortical bone is reported. A review of the pertinent orthopedic, radiologic and pathologic literature is presented, and the characteristic features of a typical periosteal chondroma are mentioned.

Total urinary excretion of hydroxyproline has been found to be significantly decreased in adult diabetics and was increased after hypophysectomy for diabetic retinopathy. There was no change in hydroxyproline excretion after the administration of 53 mg. of human growth hormone to one patient with hypopituitarism over a 4 day period.

Sapphirine-1Tc, a polymorph of sapphirine, was found in granulites near Wilson Lake, Labrador. It is triclinic with unit cell data: a=10.04, b=10.38, c=8.65 A, α=107°33′, β=95°07′, γ=123°55′. The X-ray diffraction patterns of several crystals of sapphirine from Wilson Lake were investigated and evidence was found of solid state reactions that lead from the ordered polymorph-1Tc to a disordered arrangement of domains with the structure of sapphirine-2M, that is “normal” sapphirine.

Sixty-nine hospitalized patients, who gave a history of "coronary" type chest pain appearing at rest and lasting at least 15 minutes, and whose electrocardiographic changes were limited to deeply inverted T waves predominantly in the precordial leads, were selected from a large series of patients. The hospital course and electrocardiographic changes of these patients were studied. After an average follow-up period of 4 years, approximately half the patients were still able to work. Postmortem studies on 11 patients revealed extensive sclerosis of the coronary arteries in all.

Using a psychological control (placebo) and a balanced experimental design to secure unequivocal results, it was found that pre-exercise massage yielded 2.6 percent improvement in the vertical jumping performance of 36 college men. The amount of improvement was twice as large in the fifth and sixth trials as in the preceding jumps of the six-trial test series. The average jump (48.8 cm.) and the test-retest reliability (r = .94) agreed closely with previous studies using the Henry jumping apparatus. During the six jumps of the first day (without massage), the practice effect caused 3.6 percent improvement, but there was no significant practice effect during the second or third day of testing or between three successive days spaced one week apart.

A new borate mineral has been found in a sample from Larderello, mixed with larderellite and lesser amounts of sassolite. The mineral is never well crystallized, but it constantly appears as very small, clear and colourless grains; its refractive indices are: α=1.422, β=1.435, γ=1.480. Single-crystal X-ray photographs show that the mineral is orthorombic with cell dimensions: α=11.10 A, b=11.18 A, c=9.08 A. X-ray powder diffraction and partial chemical analyses carried out on the whole sample (it being impossible to separate a sufficient quantity of pure material) confirm the foregoing data, according to which the mineral may be considered as the natural equivalent of the synthetic compound KB5O8 · 4H2O. It is likely that it originated from the reaction between potassium-bearing hot solutions and primary deposits of larderellite. It is named for the Tuscan naturalist Giorgio Santi.

The unit cell of the meteoritic mineral krinovite, NaMg2CrSia01o, is triclinic with a = 10.22, b = 10.67, c = 8.80 A, IX = 10508', {l =. 960 36', y = 12501'. The monoclinic unit cell given by OLSEN and FUCHS is one of the possible pseudomonoclinic cells. Krinovite is polysynthetically twinned with the b axis of the pseudomonoclinic cell as twin axis. The close relationships among krinovite, aenigmatite and rhonite are shown. The crystal structure of krinovite is suggested and the crystallochemical formula NaVIII2MgVI4CrVI(CrVl)02Sis018 is derived.