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Introduction: On‐demand delivery (<2 h from ordering) of alcohol is relatively new to New Zealand. We aimed to quantify the number of services available and the number of outlets available to purchase from within on‐demand services. We then tested whether access differed by neighbourhood demographics. Methods: We identified six on‐demand alcohol services and quantified access to these in Auckland, Wellington and Christchurch. Eighty‐one addresses were sampled according to three variables: (i) density of physical alcohol outlet tertile; (ii) socio‐economic deprivation tertile; and (iii) areas within the top 20th percentile of Māori within each city. Results: The median number of alcohol outlets to purchase from across all on‐demand delivery services was five, though this was higher in Christchurch. For all three cities combined, and for Wellington, the number of outlets available on‐demand was highest in areas with the highest density of physical outlets. However, the number of outlets available virtually was not associated with physical outlet density in Auckland or Christchurch. There were no significant differences in access observed for neighbourhood socio‐economic deprivation. Discussion and Conclusions: On‐demand delivery services are changing local alcohol environments, and may be increasing overall access to alcohol at a neighbourhood level. On‐demand access patterns do not consistently reflect the physical alcohol environment. The current legislative and policy environment in New Zealand pre‐dates the emergence of on‐demand alcohol services. Local councils need to consider 'virtual' access as well as physical access when developing Local Alcohol Policies. [ABSTRACT FROM AUTHOR]

Maximum photosynthetic capacity indicates that the Antarctic psychrophile Chlamydomonas raudensis H. Ettl UWO 241 is photosynthetically adapted to low temperature. Despite this finding, C. raudensis UWO 241 exhibited greater sensitivity to low-temperature photoinhibition of PSII than the mesophile Chlamydomonas reinhardtii P. A. Dang. However, in contrast with results for C. reinhardtii, the quantum requirement to induce 50% photoinhibition of PSII in C. raudensis UWO 241 (50 μmol photons) was comparable at either 8°C or 29°C. To our knowledge, this is the first report of a photoautotroph whose susceptibility to photoinhibition is temperature independent. In contrast, the capacity of the psychrophile to recover from photoinhibition of PSII was sensitive to temperature and inhibited at 29°C. The maximum rate of recovery from photoinhibition of the psychrophile at 8°C was comparable to the maximum rate of recovery of the mesophile at 29°C. We provide evidence that photoinhibition in C. raudensis UWO 241 is chronic rather than dynamic. The photoinhibition-induced decrease in the D1 content in C. raudensis recovered within 30 min at 8°C. Both the recovery of the D1 content as well as the initial fast phase of the recovery of Fv/ Fm at 8°C were inhibited by lincomycin, a chloroplast protein synthesis inhibitor. We conclude that the susceptibility of C. raudensis UWO 241 to low-temperature photoinhibition reflects its adaptation to low growth irradiance, whereas the unusually rapid rate of recovery at low temperature exhibited by this psychrophile is due to a novel D1 repair cycle that is adapted to and is maximally operative at low temperature. [ABSTRACT FROM AUTHOR]

The psychrophilic Antarctic alga, Chlamydomonas raudensis Ettl (UWO241), grows under an extreme environment of low temperature and low irradiance of a limited spectral quality (blue-green). We investigated the ability of C. raudensis to acclimate to long-term imbalances in excitation caused by light quality through adjustments in photosystem stoichiometry. Log-phase cultures of C. raudensis and C. reinhardtii grown under white light were shifted to either blue or red light for 12 h. Previously, we reported that C. raudensis lacks the ability to redistribute light energy via the short-term mechanism of state transitions. However, similar to the model of mesophilic alga, C. reinhardtii, the psychrophile retained the capacity for long-term adjustment in energy distribution between PSI and PSII by modulating the levels of PSI reaction center polypeptides, PsaA/PsaB, with minimal changes in the content of the PSII polypeptide, D1, in response to changes in light quality. The functional consequences of the modulation in PSI/PSII stoichiometry in the psychrophile were distinct from those observed in C. reinhardtii. Exposure of C. raudensis to red light caused 1) an inhibition of growth and photosynthetic rates, 2) an increased reduction state of the intersystem plastoquinone pool with concomitant increases in nonphotochemical quenching, 3) an uncoupling of the major light-harvesting complex from the PSII core, and 4) differential thylakoid protein phosphorylation profiles compared with C. reinhardtii. We conclude that the characteristic low levels of PSI relative to PSII set the limit in the capacity of C. raudensis to photoacclimate to an environment enriched in red light. [ABSTRACT FROM AUTHOR]

An unusual psychrophilic green alga was isolated from the deepest portion of the photic zone (<0.1% of incident PAR) at a depth of 17 m in the permanently ice-covered lake, Lake Bonney, Antarctica. Here we identify and report the first detailed morphological and molecular examination of this Antarctic green alga, which we refer to as strain UWO 241. To determine the taxonomic identity, UWO 241 was examined using LM and TEM and partial sequences of the small subunit (SSU), internal transcribed spacer (ITS) 1 and ITS2 regions (including the 5.8S) of the ribosomal operon. These data were compared with those of previously described taxa. We identified UWO 241 as a strain ofChlamydomonas raudensisEttl (SAG 49.72).Chlamydomonas raudensisis closely related toC. noctigamaKorshikov (UTEX 2289) as well as foraminifer symbionts such asC. hedleyiLee, Crockett, Hagen et Stone (ATCC 50216). In addition, its morphology, pigment complement, and phototactic response to temperature are reported.Chlamydomonas raudensis(UWO 241) contains relatively high levels of lutein and low chla/ bratios (1.6±0.15), and the phototactic response was temperature dependent. The Antarctic isolate (UWO 241) included the typical photosynthetic pigments found in all chla/ bcontaining green algae. It possesses a small eyespot and, interestingly, was positively phototactic only at higher nonpermissive growth temperatures. Comparison of SSU and ITS rDNA sequences confirms the identification of the strain UWO 241 asC.raudensisEttl and contradicts the previous designation asC. subcaudataWille. [ABSTRACT FROM AUTHOR]

Freshly isolated, illuminated chloroplasts oxidize water and transfer the resulting electrons through the photosynthetic electron transport chains in their thylakoid membranes to the artificial electron acceptor, dichlorophenol indophenol (DCPIP). As a consequence, DCPIP is reduced and the decline in absorbance over time can be used to measure the rate of electron transfer. When gently heated, chloroplasts lose the capacity to oxidize water and the transfer of electrons to DCPIP is eliminated. Electron transport through chloroplasts to DCPIP is restored in the presence of the artificial electron donor diphenylcarbazide (DPC). If students gain experience with the DCPIP photoreduction assay and are given information on normal chloroplast function, they should be able to predict the behavior of heat-treated chloroplasts in a variety of experimental conditions. A number of such predictions are outlined and tested. The experiments can all be conducted with a limited repertoire of equipment and easily prepared solutions. Consequently, this work is well suited to an investigative study in which each student group, in consultation with instructors, can make and test its own prediction. The ways in which changing different variables can affect the quality of the experimental results is emphasized. Additional studies, on measurements of rates of oxygen evolution and emitted chlorophyll fluorescence, are briefly described to support the inferences that heat-treated chloroplasts do not oxidize water and that the vectorial transfer of electrons through them to DCPIP is identical to that in untreated chloroplasts. [ABSTRACT FROM AUTHOR]

Five winter and five spring wheat (Triticum aestivum L.) cultivars were grown under either control conditions (20°C/250 photosynthetic photon flux density (PPFD) [μmol m-2 s-1]), high irradiance (20°C/800 PPFD) or at low temperature (either 5°C/250 PPFD or 5°C/50 PPFD). To eliminate any potential bias, the wheat cultivars were arbitrarily chosen without any previous knowledge of their freezing tolerance or photosynthetic competence. We show that the differential susceptibilities to photoinhibition exhibited between spring and winter wheat cultivars, as assessed by chlorophyll fluorescence cannot be explained on the basis of either growth irradiance or low growth temperature per se. The role of excitation pressure is discussed. We assessed the correlation between susceptibility to low-temperature photoinhibition, maximum ribulose 1,5-bisphosphate carboxylase-oxygenase (EC 4.1.1.39) and NADP-dependent malate dehydrogenase (EC 1.1.1.82) activities, chlorophyll and protein concentrations and freezing tolerance determined by electrolyte leakage. Susceptibility to photoinhibition is the only parameter examined that is strongly and negatively correlated with freezing tolerance. We suggest that the assessment of susceptibility to photoinhibition may be a useful predictor of freezing tolerance and field survival of cereals. [ABSTRACT FROM AUTHOR]