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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: 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: Kelp gulls at Península Valdés, Argentina, have recently developed the habit of feeding on pieces of skin and blubber that they gouge from the backs of southern right whales. In response, the whales flinch violently, submerge, and swim rapidly away underwater. The level of harassment in 1995 was almost five times higher than when first studied in 1984 by Thomas (1988). In 1995, 67% of attacks were aimed at large white lesions on the whales' backs. The proportion of whales with lesions increased from 0.01 in 1974 to 0.32 in 1990. Mother-calf pairs that were attacked traveled at medium and fast speeds for 3.1 h per day, compared to 0.8 h for undisturbed pairs. Mother-calf pairs are estimated to spend approximately 24% of their daylight hours in states of gullinduced disturbance. Little food is available at Península Valdés, so mothers must rely on blubber reserves to support their calves' growth, behavioral development, and migration to the feeding grounds. Even when undisturbed by gulls, mothers often curtail their calves' play and nursing bouts, suggesting that their energy reserves are limited. Increasingly intense harassment by gulls may therefore compromise calf development and might even induce right whales to abandon Península Valdés for other calving grounds.

Notes: To assess large-whale stocks following the cessation of land-based South Georgia whaling in 1965, we report three independent sighting databases: a cruise in 1997, observations from Bird Island (NW of South Georgia) between 1979 and 1998, and mariner sightings between 1992 and 1997. All species were rare, with sightings of southern right whales being the most common event. Two right whales photographed off South Georgia matched animals known from Peninsula Valdés, Argentina, a population known to be growing at 7%per annum. In contrast, blue and fin whales appeared to be less abundant. A single blue whale mother-calf pair was observed off the Shag Rocks in February 1997. Extirpation of animals from this particular feeding ground is the most likely reason for ongoing low numbers of all species. Other factors may include competition for krill by traditional predators such as penguins and seals and more recently by humans, an unusually high rate of natural mortality, habitat change such as alteration in sea ice coverage, and/or the impact of ongoing whaling. The history of this critical area of large-whale habitat and this report demonstrate the need for improved, consistent longterm monitoring of population trends for these depleted stocks.

Notes: There have been several studies of the relationships between environmental factors, particularly air pollution, and attacks of asthma. Most of these studies have ignored the potential confounding effects of aeroallergens such as pollens and fungal spores. We report a statistical analysis of the relationships between emergency admissions for asthma to a hospital in Mexico City and daily average airborne concentrations of pollen, fungal spores, air pollutants (O3, NO3, SO3. and particulates) and weather factors. Asthma admissions had a seasonal pattern with more during the wet season (May-October) than the dry season (November-April). There were few statistical associations between asthma admissions and air pollutants for the three age groups studied (children under 15 years, adults, and seniors [adults over 59 years]) in either season. Grass pollen was associated with child and adult admissions for both the wet and dry seasons, and fungal spores were associated with child admissions during both the wet and dry seasons. The analysis was done with environmental data averaged over the day of admission and the 2 previous days. Our results suggest that aeroallergens may be statistically associated more strongly with asthma hospital admissions than air pollutants and may act as confounding factors in epidemiologic studies.

Notes: Abstract In contrast to insect species, light-activated influx of divalent ions into Limulus ventral photoreceptors has proven difficult to demonstrate. We used the quench of the fluorescent indicator dye, fura-2, to measure Mn2+ influx. Limulus ventral photoreceptors were injected with fura-2 and excited at 360 nm. When the photoreceptors were bathed in 1 mmol · l−1 Mn2+, an approximately 1% per 10 s decline in the fura-2 fluorescence during intervals between 50-ms flashes was taken as a measure of Mn2+ entry in darkness. Fluorescence decline during 10-s flashes was used to monitor Mn2+ entry during the photoresponse. During the 10-s flashes we observed a small rapid decline of the fura-2 fluorescence even in the absence of Mn2+. This reflected a contamination of the fluorescence signal arising from light-induced release of intracellular calcium stores. A subsequent slower decline in fluorescence during the 10-s flash, amounting to approximately 9% per 10 s, was only observed in the presence of extracellular Mn2+ and was attributed to Mn2+ influx. This light-activated influx was not through voltage-gated calcium channels since it persisted under voltage clamp, was not stimulated by depolarizing current injections, nor blocked by NiCl2. Depletion of internal calcium stores by cyclopiazonic acid treatment did not accelerate Mn2+ influx.

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 Over the last 15 years, molecular characterization of the creatine kinase (CK) gene family has paralleled the molecular revolution of understanding gene structure, function, and regulation. In this review, we present a summary of advances in molecular analysis of the CK gene family with a few vignettes of historical interest. We describe how the muscle CK gene provided an essential model system to examine myogenic regulatory mechanisms, leading to the discovery of the binding site for the MyoD family of basic helix-loop-helix transcription factors essential in skeletal myogenesis and the characterization of the MEF2 family of factors with an A/T rich consensus binding site essential in skeletal myogenesis and cardiogenesis. Cloning and characterization of the four mRNAs and nuclear genes encoding the cytosolic CKs, muscle and brain CKs, and the mitochondrial (Mt) CKs, sarcomeric MtCK and ubiquitous MtCK, has allowed intriguing study of tissue-specific and cell-specific expression of the different CKs and analysis of structural, functional, regulatory, and evolutionary relationships among both the four CK proteins and genes. Current and future studies focus on understanding both cellular energetics facilitated by the CK enzymes, especially energy channelling from the site of production, the mitochondrial matrix and inner membrane, to various cytosolic foci of utilization, and regulation of MtCK gene expression at the cell and tissue-specific level as models of regulation of energy producing genes.