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Notes: Thin films of hydrogenated amorphous carbon (a-C:H) have been evaluated as quarter-wave, antireflection dielectric coatings for application in magneto-optic data storage media. The films, which are produced by plasma deposition from methane, have low optical absorption at 830 nm wavelength, high refractive index (n≈2.1), and provide enhancement of the polar Kerr rotation (θk) when used in conjunction with rare-earth–transition-metal (RE–TM), TbFe, or TbFeCo alloys. The chemical stability, inertness, and homogeneity of the carbon films makes them effective diffusion barriers to oxygen or water vapor and thus provides excellent protection against environmental oxidation of the RE–TM layer. Dynamic disk performance data show improved write sensitivity of the media when used with a-C:H dielectric layers.

Notes: The characteristic properties of noncritically phase-matched frequency doubling in KTiOPO4 have been investigated using ∼1 μm radiation from a Styryl-13 dye laser. Noncritically phase-matched type II second-harmonic generation was found to occur at 994.3 nm. The unusually wide angle, temperature, and wavelength tolerances observed for this nonlinear process are attractive for the design of practical blue-green laser sources. A special strained-layer InGaAs diode laser was fabricated to operate at 994 nm and generation of blue-green 497 nm radiation by noncritically phase-matched frequency doubling was demonstrated.

Notes: Field monitoring, leaching studies, and experimentation in soil biology are often now being done non-destructively using fixed installations so that measurements are made repeatedly on the same units. The resulting data for each unit (suction cup, lysimeter, incubation chamber) constitute a time series in which there may be autocorrelation. The usual methods of statistical analysis, such as the analysis of variance, must be modified or replaced by more suitable ones to take account of the possible correlation. This paper describes the split-plot design of such experiments, shows how to assess the variance–covariance matrix of residuals for uniformity by the Greenhouse–Geisser statistic, and shows how to use this statistic to adjust the degrees of freedom in a formal test of significance. It also describes more recent methods. Ante-dependence analysis identifies the extent of the temporal correlation in the data and provides approximate significance tests for the treatments. Alternatively, the paper also shows how the traditional analysis of variance may be replaced by a restricted maximum likelihood analysis which gives Wald statistics. The techniques are illustrated with data on CO2 evolved from soil incubated for 75 days in closed chambers, during which time the gas was measured on 24 occasions to give time series for three replicates of each combination of two soils (limed and unlimed) and three types of ryegrass amendment. An ante-dependence structure (extending to ninth order) weakened the usual significance test within the subunit stratum. The Wald statistics showed that there was, nevertheless, a strong interaction between the treatments and time.

Notes: Summary These supporting concepts enable us to much more adequately understand the meaning of apoha. First, a sharp distinction is drawn between the real and the conceptual; the real is particular, unique, momentary and the basis of perception, while the conceptual is universal, general, only supposedly objective and the basis of language. Second, the complex nature of negation discloses the kind of negation meant by apoha. Negation by implication is seen as disclosing the necessary relation between simple affirmations and simple negations. It is in this sense that Dignaga asserts that the meaning of words lies in the negation of the opposite. Third, the idea of apoha as the differentiation of concepts is to be distinguished from the Nyāya-Vaiśe $$\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle\cdot}$}}{s}$$ ika notion of exclusion as a materially present quality in objects. Ratnakirti, and Mok $$\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle\cdot}$}}{s}$$ ākaragupta following him, use the idea of negation by implication to explain apoha as the simultaneity of and logical relation between a positive assertion concerning an epistemological object and a negative assertion concerning all things which are not that epistemological object. For example, Ratnakirti in accordance with the theory of apoha explains that the term cow “harbors” the negation of non-cow in the same way that blue is harbored in the term blue lotus. The exclusion of the other, i.e., the negation of the non-cow, is held by Ratnakirti to be an actually apprehended attribute of the cow cognized (as distinct from the cow in itself). He says “... discrimination of non-cow inevitably arises simultaneously with the perception of the cow, for (the negation of non-cow) is the qualifier (of the individual).” This interaction between the positive and the negation of the other, i.e., the relation of negation by implication, as a simultaneous interaction is necessary lest when, e.g., asked to tie up a cow one ties up a horse instead. Mok $$\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle\cdot}$}}{s}$$ ākaragupta denies three possible interpretations of apoha before putting forth his own definition. The first is that when an external object is conceptualized this is done as “the other (the dissimilar) is discriminated from this.”The second is much the same, only it is in terms of the mental image, i.e., the epistemological object rather than the ontological object as in the first. The third is that apoha means the negation of an assertion, i.e., the simple absence of the other. All three of these interpretations are unacceptable to Mok $$\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle\cdot}$}}{s}$$ ākaragupta. He defines apoha as “the affirmation (of a positive entity) qualified by discrimination (of it from all other entities).” Mok $$\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle\cdot}$}}{s}$$ ākaragupta goes on to explain this simultaneity more fully: ... those who stress affirmation think that after we have known the cow, we consequently determine the discrimination of the essence of the cow from that of the non-cow; those who stress the negative function of apoha are of the opinion that we first know the discrimination of the dissimilar thing and then consequently confirm the thing which is discriminated from others, viz., the cow. Thus (both interpretations) are wrong. For at the time of judgment we do not experience an order of comprehension in which (negation or affirmation) occurs first. In fact, it is not the case that one, having understood the affirmation, later confirms the negation by implication, or that one having understood the negation later confirms what is discriminated (from the dissimilar). Therefore, we say that the very understanding of the cow is the same as the understanding of what is discriminated from the dissimilar. We can see from this that for Ratnakirti and Mok $$\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle\cdot}$}}{s}$$ ākaragupta apoha meant the simultaneous affirmation of and negation of the dissimilar from the (epistemological) object. Mok $$\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle\cdot}$}}{s}$$ ākaragupta's concern with the “time of judgment” also shows that the idea of apoha was understood by them as being psychologically descriptive. In the process of identifying an epistemological object as some particular thing, neither the negative nor the positive function have priority but are, rather, complementary one to the other. This simultaneity and complementarity are supported by the examination of mind “at the time of judgment,” i.e., it is a psychological description of the process of identification of an epistemological object as some particular thing. It is this fact of apoha describing the process of identification which, as described above, places apoha in the inference category of sources of truth. Apoha is clearly, therefore, involved with words and concepts rather than being on the perception side where it would have to be a metaphysical concept describing the real or absolute. Putting the idea of apoha into contemporary terms we can say that it is a psychological descriptor for the bipolar relation of concepts. Dignaga and the other Buddhist logicians are then to be understood here as being involved in producing a phenomenological description of linguistic thought processes. More broadly, as in the discussion of perception, they are involved in the phenomenological description of consciousness, a favorite Buddhist undertaking. As such, the work of the Buddhist logicians fits into the larger soteriological intention of all Buddhist thinkers, since enlightenment is understood to follow from insight into the nature of consciousness as productive of suffering. Some authors have criticized the logicians as being overly concerned with the un-Buddhist occupation of arguing. However, when their work is seen as expanding our understanding of the nature and working of consciousness, the logicians are certainly worthy of our respect.

Notes: Abstract: We assessed a new dual-energy bone densitometer, the PRODIGY, that uses a narrow-angle fan-beam (4.5°) oriented parallel to the longitudinal axis of the body (i.e., perpendicular to the usual orientation). High-resolution scans across the body can be stepped at 17 mm intervals. The energy-sensitive array detector uses cadmium zinc telluride, which allowed rapid photon counting. Spine and femur scans required 30 s, and total-body scans required 4–5 min; the dose was only 3.7 mrem and 0.04 mrem respectively, or about 5 to 10 times lower than conventional fan-beam densitometry. We found only a small influence of soft-tissue thickness on bone mineral density (BMD) results. There was also a small ( ± 1%) influence of height above the tabletop on BMD results. A software correction for object height allowed a first-order correction for the large magnification effects of position on bone mineral content (BMC) and area. Consequently, the results for BMC and area, as well as BMD, with PRODIGY corresponded closely to those obtained using the predecessor DPX densitometer, both in vitro and in vivo; there was a generally high correlation (r= 0.98–0.99) for BMD values. Spine and femur values for BMC, area and BMD averaged within 0.5% in vivo (n= 122), as did total-body BMC and BMD (n= 46). PRODIGY values for total-body lean tissue and fat also corresponded within 1% to DPX values. Regional and total-body BMD were measured with 0.5% precision in vitro and 1% precision in vivo. The new PRODIGY densitometer appears to combine the low dose and high accuracy of pencil-beam densitometry with the speed of fan-beam densitometers.

Notes: Extracts of term human placenta were tested for enhancement of proliferative growth of primary cultures of human keratinocytes. Saline extracts or supernatants from homogenates were dialyzed extensively, lyophilized, and tested in subcultures of keratinocytes in MCDB 153 medium with 0.1 mM Ca++ containing only defined supplements (insulin, hydrocortisone, transferrin, ethanolamine, phosphoethanolamine). Cells plated in the absence of EGF at moderately high densities (1000-3000 cells per cm2) formed colonies and grew in the presence of placental extract at 25-500 μg/ml. Extracts of cord serum or maternal serum were inactive, suggesting that the activity is derived from placental tissue. The activity is not EGF, since the activity in the placental extract, unlike EGF, did not promote growth at low cell density, was synergistic with EGF under some conditions, and did not produce changes in colonial morphology which occurred in the presence of EGF. Unlike keratinocyte growth-promoting activity in bovine hypothalamic extract, the activity is nondialyzable and is destroyed at 100°C. Placental extract could not replace any of the defined components of the medium and is therefore distinct from them. The presence of activity in the placenta with distinctive properties suggests that this is a previously undescribed material with growth-promoting properties for epithelium.

Notes: The dispersion of transition metal sols (gold, ferric hydrous oxide, chromium hydroxide) in a water soluble polymer (PVA 4-88) was investigated and from the films produced, a comparison made of their mechanical and electrical properties. Extending to non aqueous solvents (dimethylformamide, tetrahydrofuran) interactions of polyvalent metal ions (Fe(III), Al(III), Ti(IV), Zr(IV), Pd(0), Ag(0), Au sols) with a specific metal complexing polymer (poly(acrylamideoxime)) and a block copolymer containing styrene and butadiene (Buna BL 6533) were investigated.