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We present a nonlinear optical (NLO) probe technique, wavelength-dependent Z-scan nonlinear spectroscopy (WDZNS), which can be utilized for assessing broadband NLO properties of materials. Unlike typical Z-scans, WDZNS can spectrally monitor the frequency-doubled output as a function of wavelength λ as well as input intensity I. Based on WDZNS we have investigated the strong impact of two-photon absorption (TPA) on second-harmonic generation in CdTe over a broad TPA range. This complicated NLO effect is characterized by the λ-dependent TPA coefficient, which is consistent with a simple two-band model. The relative second-order NLO dispersion derived from WDZNS is also consistent with previous measurements.

In this paper we present the discussions of the Eltham group in the Greenwich Open-Space project, as a case study of the contributions that in-depth small groups can make in the study of environmental values. The major themes of the group discussions are presented, and extracts of dialogue illustrate several aspects of small-group dynamics: how the group establishes its identity, how members negotiate increasing levels of intimacy and trust, how they handle conflict among themselves, and how they deal with termination. These themes demonstrate the importance of the group matrix, the levels of manifest and latent meaning in discourse, and the role of the conductor in facilitating the group structure and processes. We conclude that in-depth small groups are a valuable research strategy for the exploration of the interpenetration of individual and collective values for environment.

Empirical qualitative research is gaining recognition within social and humanistic geography, although the ‘small group’ is not yet recognised as a valuable research technique. In this paper we review the use of once-only group interviews in social and market research, and then discuss the principles of Group-analytic psychotherapy as a way of conducting in-depth small groups. By means of a discussion of the Greenwich Open-Space Project, we explore the methodological issues involved in conducting in-depth small groups with local people, discuss the interpretive strategies which can be used to handle large amounts of linguistic data, and present the major findings from the project.

Ridging or “earthing up” reduced the number of tillers per plant in all experiments. Its effects were mainly due to the mechanical hindrance of soil on the emergence of tillers and their consequent etiolation. Low light intensity delayed the tillering process and enhanced the effect of ridging. Nutrient deficiency reduced the number of tillers. Ridging treatments generally increased the plant height and dry weight, which was attributed to the further development of crown parts and root systems.

Yield was associated directly with cutting interval, regrowth being stimulated by frequent cutting for only a short period. Water consumed, per unit of forage produced, decreased as length of cutting interval increased. Sudangrass used moisture from the upper foot of soil and was more efficient in water use than alfalfa during June, July, and August. Consumptive use of water was closely associated with rainfall during the period of active plant growth.

Superphosphate increased oat yields more than did rock phosphate, even when applied on a citrate soluble basis. Rock phosphate resulted in higher yields of alfalfa hay and roots than did superphosphate in all but two cases. Lime did not greatly reduce the effectiveness of rock phosphate, except on one soil where the pH was raised to 8.0.

We report on broadband nonlinear optical (NLO) responses from a phase-change chalcogenide compound K_4GeP_4Se_12. Its glassy phase exhibits unusual second-harmonic generation (SHG) due to the preservation of local crystallographic order. The SHG efficiency of the glassy form can be boosted by more than 2 orders of magnitude by simple heat treatment. Strong SHG and third-harmonic generation from both glassy and crystalline compounds were characterized over a wide wavelength range of 1.2–4.0  μm. Our results imply that K_4GeP_4Se_12 can be utilized for various NLO applications in the mid-infrared spectrum.

The root hairs of 1‐month‐old intact barley (Hordeum vulgareL.) seedlings, grown in a growth chamber, were observed at three different constant root temperatures. Formation and elongation of root hairs were recorded hourly over 24‐hour periods. Death of root hairs was indicated by the use of neutral red; from these data longevity was determined. The number of root hairs formed was greater at 18 and 26C than at 15C. Formation was periodic, with three maxima and two minima rates. The changes in formation rates did not coincide precisely at each temperature. Elongation was greater at 26C than at 15C. The elongation rate was constant for each of the three temperatures over a 24‐hour period. Longevity of root hairs was 40, 45, and 55 hours at 26, 18, and 15C, respectively. A maximum number of deaths occurred 13 to 15 hours after the initiation of the light period. Phasic formation and death of root hairs may affect diurnal water absorption due to changes in the living and dead root hair areas. Elongation rate may also affect diurnal water uptake, in that elongation rate is affected by soil conditions.