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Nitrogen-containing heterocyclic compounds play an important role in several biological processes. Furthermore, their biological activity seems often to depend upon interaction with a metal ion. Interest in the study of hydrazones and their metal complexes has been growing because of their physiological activity, coordination capability and application in analytical chemistry.1,2 Many hydrazones and their metallic derivatives show very interesting biological activity, e.g., as antitumour or anticonvulsant agents, and behave as cytotoxic compounds toward tumour cells.3 During the past few years, in addition to platinum compounds, coordination compounds of palladium(II) and (IV) seem to be promising in cancer chemotherapy.4 Due to the biological activity of heterocyclic hydrazones and in continuing our systematic investigations of the platinum group metals with hydrazones and generally with heterocyclic nitrogen donor ligands,5-10 we report here the crystal structure of dibromo(phenyl-2-pyridyldimethylhydrazone) palladium(II).

Nanomolar concentrations of charybdotoxin or dendrotoxin increase the cytoplasmic free Ca 2+concentration in isolated central nerve terminals. The effects of the two toxins, normally considered to be blockers of K +channels controlled by voltage in a Ca 2+-sensitive or -insensitive manner, respectively, show only marginal additivity. Apamin, an inhibitor of low conductance Ca 2+-activated K +channels, was without effect in either the absence or presence of dendrotoxin. The effect of charybdotoxin on polarized, isolated central nerve terminals seems to be mediated largely by a block of K +channels sensitive to dendrotoxin. Apparently, these voltage-operated K +channels make a more significant contribution to maintaining the polarized potential of synaptosomes than do those activated by Ca 2+.

The gene encoding the tetrameric malate dehydrogenase (MDH) in a thermophilic Bacillus species (BI) has been cloned in an Escherichia coli plasmid. The nucleotide sequence of the gene, the first to be elucidated for a tetrameric MDH, shows the MDH subunit to contain 312 amino acids and have a molecular mass of 33648 Da, which confirms the experimentally determined value of about 35 kDa. Like the genomic DNA of BI, the MDH gene is relatively AT-rich; this contrasts with the generally GC-rich nature of the DNA of thermophilic Bacillus species. Comparison of amino acid sequences reveals that BI MDH bears greater structural similarity to lactate dehydrogenases (LDHs) than to other (dimeric) MDHs. MDHs and LDHs resemble each other in catalytic mechanism and several other respects. However, whereas MDHs in the majority of organisms are dimers, the tetrameric structure is favoured among LDHs. The stronger structural resemblance that BI MDH has to LDHs than to the dimeric MDHs provides some explanation as to why Bacillus MDH, unlike most other MDHs, is tetrameric. A 1 kb fragment containing the BI MDH gene, produced in a PCR, has been cloned into a high-expression E. coli plasmid vector. BI MDH synthesized from this clone constitutes about 47% of the total protein in cell extracts of the E. coli strain carrying the clone. MDH purified from BI and that purified from the E. coli strain carrying the MDH gene clone appear to be identical proteins by several criteria. A number of characteristics of the MDH have been elucidated, including the molecular masses of the native enzyme and the subunit, N-terminal amino acid sequence, isoelectric point, pH optimum for activity, thermostability, stability to pH, urea and guanidinium chloride and several kinetic parameters. Whereas the MDH is a stable tetramer in the pH range 5–7, it appears to be converted into a stable dimer at pH 3.5. This suggests that the dimer is a stable intermediate in the dissociation of the tetramer to monomers at low pH.

A method is described for the preparation of ‘free’ and ‘synaptosomal’ brain mitochondria from fractions of guinea-pig cerebral cortex respectively depleted and enriched in synaptosomes. Both preparations of mitochondria have a low membrane H+conductance, a high capacity to phosphorylate ADP, and a capacity to accumulate Ca2+ at rates limited by the activity of the respiratory chain. Ca2+ transport by ‘free’ brain mitochondria is compared with that of heart mitochondria. The Ca2+ conductance of ‘free’ brain mitochondria was at least 20 times that for rat heart mitochondria. Ca2+ uptake by brain mitochondria increased the pH gradient and decreased membrane potential, whereas little change occurred during the much slower uptake by heart mitochondria. In the presence of ionophore A23187, dissipative Ca2+ cycling decreased the H+ electrochemical potential gradient of brain mitochondria from 190 to 60mV, but caused only a slight decrease with heart mitochondria, although the ionophore lowered the pH gradient and increased membrane potential. The Ca2+ conductance of ‘free’ brain mitochondria is distinctive in showing a hyperbolic dependency on free Ca2+concentration. In the presence of Ruthenium Red, a rapid Na+ -dependent Ca2+ efflux occurs. The H+ electrochemical potential gradient is maintained during this efflux, and membrane potential increases, with both ‘free’ brain and heart mitochondria. The Na+ requirement for Ca2+ efflux appears not to be related to the high Na+/H+ exchange activity but may represent a direct exchange of Na+ for Ca2+.

Mono-ligand complexes derived from 2-acetylpyridine hydrazone (APH) and 2-benzoylpyridine hydrazone (BPH) have been prepared with palladium(II) salts. Their physical properties including molar conductance measurements and spectral (IR, 1H-nmr and d-d) data are discussed in terms of possible structural types and the nature of bonding. No bis-ligand complexes have been prepared. The ligands appear to coordinate in the solid state via both pyridine and methylene nitrogen atoms but a change of bonding mode appears to occur when the solid complexes are dissolved in DMSO. A paramagnetic green species has been reproducibly prepared from Li2PdCl4 and APH.

The complexes M(phzH)2(SO4)2 (M=Mn, Fe, Co, Ni, Zn, phzH = monoprotonated β-phenylethyl-hydrazine) have been isolated Evidence from ultraviolet and infrared spectroscopy indicates that they contain six-coordinated metals bonded to phenylethylhydrazinium cations and linked to each other by double sulphato-bridges. Coordination compounds containing β-phenylethylhydrazine have been prepared of three types, MX2(phz)2(M=Mn, X=Br, M=Co, X=Cl, Br, I; M=Ni, X=Br, M=Zn, X=Br) MX 2(phz) (M=Zn, X=Cl, Br, NCS) and MX2(phz)3(M=Ni, X=I). Spectroscopic and magnetic methods have been used to assign structures to these compounds.

The noun “radical” as applied to reformers who held advanced views came into general use in the early nineteenth century. It was at first used in a derogatory sense, denoting, as Walter Scott wrote in 1819, “a set of blackguards.” However, it was taken up by the subjects of the intended abuse and quickly acquired a certain respectability—so much so that by 1830 one middle-class radical was recording that “the term Radical once employed as a name of low reproach, has found its way into high places, and is gone forth as the title of a class who glory in their designation.” Reformers from across the political spectrum were soon being designated “radical,” as can be seen from the application of the term to individuals as diverse in outlook as Lord Durham, Richard Oastler, and Bronterre O'Brien.This eclecticism has led historians to pronounce the concept useless as a tool of historical analysis. If any tradition at all emerges from studies of English radicalism, then it is a tradition of liberal humanitarianism, a pattern of reform that is nonclass and nonideological. At best “radical” retains its original adjectival power of describing a root-and-branch reformer, an individual who worked to change quite substantially existing economic, political, or social structures by word or deed. But the evident contradictions and discontinuities in the so-called “radical tradition” have made historians balk at making further claims than these. This essay, however, is a provisional attempt to shift the focus away from the personalities and the specificities of reform movements in their peculiar conjunctural moments to the operation of radicalism as a powerful ideology that, far from being nonclass and nonideological and despite (or even possibly because of) its internal contradictions, has profoundly influenced class development and class relations.

Between 1848 and 1853 a series of major peace congresses was held—in Brussels (1848), Paris (1849), Frankfurt (1850), London (1851), Manchester (1853), and Edinburgh (1853). This midcentury period was one of great confidence and optimism in the likely success of the cause. Indeed, reading the reports of the congresses today, one is struck by the at times naive overoptimism of many delegates. This may in part have been the product of the millenarian atmosphere of the period. However, it has to be said that the congresses were also characterized by a strong sense of the practicalityof their proposals and the steady progress toward their goal that implementation of such proposals would achieve. Above all, the efflorescence of the peace movement in the short six years around the midcentury was the product of a class confidence, of a momentary triumphalism that inspired a section of the bourgeoisie to believe that the scourge of war could be eradicated at last.The nineteenth-century peace movement effectively began with the establishment toward the end of the Napoleonic Wars, independently and virtually simultaneously, of peace societies in the United States and Britain. They were dominated by men of religion, particularly Quakers, and for a quarter of a century their work was essentially that of proselytizing the peace cause through publicity, petitions, and lecture tours. In connection with the last, the London Peace Society sent emissaries on tours of continental Europe in the early 1840s to spread the peace message.

One World to Share: selected speeches of the Commonwealth Secretary-General, 1975-9. Shridath Ramphal, London: Hutchinson Benham. 1979. 444 pp. £10.95The White House Years. Henry Kissinger, London: Weidenfeld and Nicolson & Michael Joseph. 1979. 1545 pp. £14.95Kissinger and the Meaning of History. Peter W Dickson, Cambridge University Press. 1978. 207 pp. £8.95Beyond Kissinger: ways of conservative statecraft. George Liska, London: Johns Hopkins University Press. 1975. 169 pp. $2.95Where the Grass is Greener. David M Smith, Harmondsworth, England: Penguin. 1979. 386 pp. £2.25Small-Scale Irrigation. Peter Stern, London: Intermediate Technology Publications. 1979. 152 pp. npThe Social and Ecological Effects of Water Development in Developing Countries. Edited by Carl Widstrand, Oxford: Pergamon. 1978. 120 pp. £10.00Water in a Developing World: the management of a critical resource. Edited by Albert E Utton & Ludwik Teclaff, Boulder, Colorado: Westview Press (distributed in the UK by Ernest Benn). 1978. 282 pp. £13.75Marx and the End of Orientalism. Bryan S Turner, London: George Allen & Unwin. 1978. 98 pp. £3.50Project Planning for Developing Economies. WW Shaner, New York: Praeger. 1979. 235 pp. £14.25International Development Administration: implementation analysis for development. Edited by G Honadle & Rudi Klaus, New York: Praeger. 1979. 221 pp. £13.00Nutrition and National Policy. Edited by Beverly Winikoff, London: MIT Press. 1979. 580pp. £15.75The Nuclear Question: the United States and nuclear weapons, 1946-76. Michael Mandelbaum, Cambridge University Press. 1979.277 pp £12.50Force Without War: US armed forces as political instruments. Barry M Blechman & Stephen S Kaplan, Washington DC: Brookings Institution (distributed in the UK by Blackwells). 1978. 584 pp. £15.00. £6.50 pbNuclear Arms in the Third World: US policy dilemma. Ernest W Lefever, Washington DC: Brookings Institution (distributed in the UK by Blackwells). 1979. 154 pp. £8.50. £3.25 pbThe Nonaligned Movement: the origins of a Third World alliance. Peter Willetts, London: Frances Pinter. 1978.310 pp. £12.50Coups and Earthquakes: reporting the world for America. Mort Rosenblum, New York: Harper & Row. 1979. 230 pp. £5.95Nations and States. Hugh Seton-Watson, London: Methuen. 1979.563 pp. £12.00Rich World, Poor World. Geoffrey Lean, London: George Allen & Unwin. 1978.335pp. £4.50 pbYour Own Pigs You May Not Eat: a comparative study of New Guinea societies. Paula G Rubel and Abraham Rosman University of Chicago Press. 1978.368pp. £14.40Afterthoughts on Material Civilisation and Capitalism. Fernand Braudel, Baltimore: Johns Hopkins University Press. 1977.120 pp. $7.95Women in the Muslim World. Edited by Lois Beck & Nikki Keddie, Harvard University Press. 1979. 698 pp. £18.00The Economics of Multinational Enterprise. Neil Hood & Stephen Young, London: Longman Group. 1979. 412 pp. £7.95 pbThe Social and Cultural Impacts of Transnational Enterprises. Krishna Kumar, University of Sydney. Transnational Corporations Research Project (Working Paper No 6). 1979. 183 pp.A New Stage in International Relations. N I Lebedev, Oxford: Pergamon. 1978. 253 pp. $20.00The Political and Military Laws of War. J Lider, Farnborough, England: Saxon House. 1979. 266 pp. £10.50.Becoming Modern. Alex Inkeles & David H Smith, London: Heinemann Educational. 1974.436 pp. £5.00The Capitalist World Economy. Immanuel Wallerstein, New York: Cambridge University Press. 1979. 305pp. £15.00South Africa: the method in the madness. John Kane-Berman, London: Pluto Press. 1979. 265 pp. £2.95 pbWhite Man, We Want to Talk to You. Denis Herbstein, London: Andre Deutsch. 1979. 270 pp. £4.95Africa Undermined: a history of the mining companies and the underdevelopment of Africa. G Lanning with M Mueller, Harmondsworth, England: Penguin. 1979. 590 pp. £3.50Africanisation, Nationalisation and Inequality: mining labour and the copper belt in Zambian development. Philip Daniel, Cambridge University Press: 1979.202 pp. £12.50. £5.95 pbNasser and His Generation. PJ Vatikiotis, London: Croom Helm. 1978. 375 pp. £11.95Politics Mainly Indian. W H Morris-Jones, Bombay: Orient Longman. 1978. 392 pp. Rs 60.00Papua New Guinea: its economic situation and prospects for development. G W Baldwin et al, London: Johns Hopkins University Press. 1978.223 pp. £4.50 pbParadise Postponed: essays on research and development in the South Pacific. Edited by Alexander Mamak & Grant McCall, Oxford: Pergamon. 1978. 277 pp. £11.25Urbanisation in Papua New Guinea: a study of ambivalent townsmen. Hal B Levine & Marlene Wolfzahn Levine, Cambridge University Press. 1979.161 pp. £8.95. £3.95 pbThe Land of Promise: A critique of political Zionism. Abdelwahab M Elmessiri, New Brunswick, New Jersey: North American. 1977.255 pp. $6.95 pbASEAN Economies in Perspective: a comparative study of Indonesia, Malaysia, the Philippines, Singapore and Thailand. John Wong, London: Macmillan. 1979.217 pp. £3.95 pbChina's Role in World Affairs. Michael B Yahuda, London: Croom Helm. 1978. 300 pp. £10.95. £4.95 pbMao's China: a history of the People's Republic. Maurice Meisner, New York: Free Press. 1977. 416 pp. npChina and the Major Powers in East Asia. A Doak Barnett, Washington, DC: Brookings Institution (distributed in the UK by Blackwells). 1977. 416 pp. npChinese Politics After Mao. Edited by Jurgen Domes, Cardiff, Wales: University College Cardiff Press. 1979. 291 pp. npSão Paolo: growth and poverty. A Report from the São Paolo Peace and Justice Commission, with an introduction by Cardinal Arns, Archbishop of Säo Paulo. London: The Bowerdean Press (in association with The Catholic Institute for International Relations). 1978.128 pp. £3.40Frontier Development Policy in Brazil: a study of Amazônia. Dennis J Mahar, New York: Praeger. 1979.182 pp. £10.50Arise Ye Starvelings: the Jamaican labour rebellion of 1938 and its aftermath. Ken Post, London: Institute of Social Studies/The Hague: Martinus Nijhoff. 1979.502 pp. npThe Future of the Inter-American System. Edited by TJ Farer, London: Praeger. 1979. 290 pp. £13.00

Ca 2+entry is a prerequisite for both exocytosis and the phosphorylation of synapsin I and MARCKS proteins in mammalian cerebrocortical synaptosomes. The novel spider toxin Aga-GI completely blocks KCl-evoked glutamate exocytosis but only partially inhibits KCl-evoked cytoplasmic Ca 2+elevations, thus revealing at least two pathways for KCl-induced Ca 2+entry. Aga-GI completely attenuates KCl-induced phosphorylation of synapsin I and MARCKS proteins. We therefore conclude that both exocytosis and the phosphorylation of synapsin I and MARCKS proteins are specifically coupled to Ca 2+entry via a subset of voltage dependent Ca 2+channels at the nerve terminal which are sensitive to Aga-GI.

Tetranitromethane reacts with the uncoupling protein of intact brown fat mitochondria. The chloride permeability in the absence of the inhibitory nucleotide GDP is not affected, but the affinity with which GDP binds is decreased, and the coupling between binding of nucleotide and inhibition of chloride permeation is broken.

Ca2+entry is a prerequisite for both exocytosis and the phosphorylation of synapsin I and MARCKS proteins in mammalian cerebrocortical synaptosomes. The novel spider toxin Aga‐GI completely blocks KCl‐evoked glutamate exocytosis but only partially inhibits KCl‐evoked cytoplasmic Ca2+elevations, thus revealing at least two pathways for KCl‐induced Ca2+entry. Aga‐GI completely attenuates KCl‐induced phosphorylation of synapsin I and MARCKS proteins. We therefore conclude that both exocytosis and the phosphorylation of synapsin I and MARCKS proteins are specifically coupled to Ca2+entry via a subset of voltage dependent Ca2+channels at the nerve terminal which are sensitive to Aga‐GI.

London Against Racism in Housing, Anti-Racism for the Private Rented Sector, London: London Against Racism in Housing, 1988, 122 pp., n.p.Marc Reuver, Christians as Peacemakers, Geneva: World Council of Churches, 1988, 84 pp., £3.75 p.b.Robin Boyd, Ireland: Christianity Discredited or Pilgrim's Progress, Geneva: WWC Publications, 1988, 127 pp., £4.75 p.b.Mairtin Mac an Ghaill, Young, Gifted and Black: Student-Teacher Relations in the Schooling of Black Youth, Milton Keynes: Open University Press, 1988, 184 pp., £25.00 h.b., £8.95 p.b.William Montgomery Watt, Islamic Fundamentalism and Modernity, London: Routledge, 1988, 158 pp., £25.00 h.b.John Rex and David Mason (eds), Theories of Race and Ethnic Relations, Cambridge, Cambridge University Press, 1988, 363 pp., £9.95 p.b.John Solomos, Black Youth, Racism and the State: The Politics of Ideology and Policy, Cambridge: Cambridge University Press, 1988, 284 pp., £27.50 h.b.Tony Kushner, The Persistance of Prejudice: Anti-Semitism in British Society during the Second World War, Manchester: Manchester University Press, 1989, 245 pp., £29.95 h.b.Geoffrey Alderman, London Jewry and London Politics 1889-1986, London: Routledge, 1988, 186 pp., £35.00 h.b.Anne J. Kershen, Trade Unionism among the Jewish Tailoring Workers of London, 1872-1915, Research Paper No 1, London Museum of Jewish Life, 1988, 39 pp., £3.00 p.b.Samuel Almog (ed), Anti-Semitism Through the Ages, London: Pergamon Press, 1988, 419 pp., £32.00 h.b., £14.95 p.b.Frances Robinson, Varieties of South Asian Islam, Research Papers in Ethnic Relations No 9, Centre for Research in Ethnic Relations, University of Warwick, 1988, 27 pp., £3.50 p.b.A.R.F. Webber, Those That Be In Bondage: A Tale of Indian Indentures and Sunlit Western Waters, Wellesley, MA: Cataloux Publications, 1988, 236 pp., n.p.Jean Ellis, Breaking New Ground: Community Development with Asian Communities, London: Bedford Square Press, 1989, 166 pp., £6.95 p.b.Sophie Watson, Accommodating Inequality: Gender and Housing, London: Unwin Hyman, 1989, 156 pp., £9.95 p.b.Paul Sieghart (ed), Human Rights in the United Kingdom, London: Pinter Publishers, 1988, 139 pp., £22.50 h.b., £6.95 p.b.Dilys M. Hill (ed), Human Rights and Foreign Policy: Principles and Practice, Basingstoke: Macmillan Centre for International Policy Studies, University of Southampton, 1989, 208 pp., £35.00 h.b.John Rex, The Ghetto and the Underclass: Essays on Race and Social Policy, Aldershot: Avebury, 1988, 140 pp., £21.00 h.b.Robert Dent, Faith of Our Fathers: Roman Catholic Schools in a Multi-Faith Society, Coventry: City of Coventry Education Department, 1988, 198 pp., £7.60Lena Dominelli, Anti-Racist Social Work: A Challenge for White Practitioners and Educators, London: Macmillan, 1988, 189 pp., £20.00 h.b., £6.95 p.b.Joe Harte (ed), Black People and the Media, Equality in Employment and Training: Policies and Practice, London/Coventry: London Borough of Lewisham and the Commission for Racial Equality in conjunction with the University of Warwick, 1988, 122 pp., n.p. p.b.Kaushika Amin, Mavis Fernandes and Paul Gordon, Racism and Discrimination in Britain: A Select bibliography 1984-87, London: Runnymede Trust, 1988, 98 pp., £3.95 p.b.Paul Gordon, Race in Britain: A Research and Information Guide, London: Runnymede Trust, 1988, 56 pp., £3.50 p.b.Lincoln Octavious Williams, Partial Surrender: Race and Resistance in the Youth Service, Basingstoke: Falmer Press, 1988, 200 pp., £17.95 h.b., £8.50 p.b.

Mitochondrial depolarisation has been reported to enhance the generation of superoxide anion (O⋅−2) in a number of cell preparations while an inhibition has been observed with isolated mitochondria. Cerebellar granule cells equilibrated with >1 μM hydroethidine (dihydroethidium) which is oxidised to the fluorescent ethidium cation by O⋅−2showed a large increase in fluorescence on protonophore addition. However, controls showed the fluorescent enhancement to be a consequence of release of unbound preformed ethidium from the mitochondrial matrix within the cell with resultant fluorescent enhancement. This ambiguity was removed by the use of low (1 μM) concentrations of dye in which case generated ethidium remained bound within the mitochondria. Under these conditions antimycin A, but not protonophore addition, produced an increase in fluorescence. It is concluded that excess ethidium acts as an indicator of mitochondrial membrane potential obscuring the monitoring of O⋅−2and that certain experiments employing this indicator in cells may require re‐evaluation.

Philip E. Ogden and Paul E. White (eds), Migrants in Modern France: Population Mobility in the Later 19th and 20th Centuries London: Unwin Hyman, 1989, 320 pp., £45.00 h.b.Hastings Donnan, Marriage among Muslims: Preference and Choice in Northern Pakistan Delhi: Hindustan Publishing Corporation, 1988, 231 pp, $38.25 p.b.Malcolm Cross and Gad Heuman (eds), Labour in the Caribbean: from Emancipation To Independence Basingstoke: Macmillan Caribbean, 1988, 329 pp., £10.95 p.b.Richard Jenkins (ed), Northern Ireland: Studies in Social and Economic Life Aldershot: Avebury with the Economic and Social Science Research Council, 1989, 209 pp., £23.50 h.b.Raminder Singh, Asian and White Perceptions of the Teaching Profession Bradford: Bradford and Ilkley Community College, 1988, 56 pp., £2.50 p.b.Gajendra Verma and Peter Pumfrey (eds), Educational Attainments: Issues and Outcomes in Multi-cultural Education Lewes: The Falmer Press, 1988, 190 pp., £17.95 cloth, £8.95 p.b.Joel Perlmann, Ethnic Differences: Schooling and Social Structure among the Irish, Italians, Jews and Blacks in an American City, 1880-1935 Cambridge: Cambridge University Press, 1988, 336 pp., £30.00 h.b.Mervyn C. Alleyne, Roots of Jamaican Culture London: Pluto Press, 1988, 186 pp., £14.95 h.b.Gajendra K. Verma and Christopher Bagley (eds), Cross-Cultural Studies of Personality Attitudes and Cognition Basingstoke: Macmillan, 1989, 217 pp., £33.00 h.b.Roland Littlewood and Maurice Lipsedge, Aliens and Alienists: Ethnic Minorities in Psychiatry, 2nd ed. London: Unwin Hyman, 1989, 334 pp., £32.00 h.b., £10.95 p.b.Valerie Marrett, Immigrants Settling in the City London: Leicester University Press, 1989, 207 pp., £30.00 h.b.Paul B. Pedersen (et al) (eds), Counselling Across Cultures, 3rd ed. London: University of Hawaii Press, 1989, 402 pp., £14.35 p.b.Anthony Lerman (ed), The Jewish Communities of the World: A Contemporary Guide, 4th ed. Basingstoke: Macmillan in association with the Institute for Jewish Affairs, 1989, 206 pp., £25.00 h.b.Gerard Chaliand (ed) Minority People in the Age of Nation-States London: Pluto Press, 1989, 160 pp., £18.00 h.b., £7.95 p.b.Edward Pilkington, Beyond the Mother Country: West Indians and the Notting Hill White Riots London: I.B. Tauris and Co., 1988, 180 pp., £10.95 h.b.E. Ellis Cashmore, United Kingdom? Class, Race and Gender since the War London: Unwin Hyman, 1989, 254 pp., £28.00 h.b., £9.95 p.b.Mark Duffield, Black Radicalism and the Politics of De-Industrialisation: The Hidden History of Indian Foundry Workers Aldershot: Avebury, 1988, 240 pp., £24.00 h.b.Fiona Williams, Social Policy: A Critical Introduction Cambridge: Polity Press, 1989, 240 pp., £29.50 h.b., £7.95 p.b.Stephen Brook, The Club: The Jews of Modern Britain London: Constable, 1989, 464 pp., £15.95 h.b.Paul Spoonley, The Politics of Nostalgia: Racism and the Extreme Right in New Zealand Palmerston North: The Dunmore Press, 1987, 318 pp., n.p. p.b.Kayleen M. Hazlehurst, Racial Conflict and Resolution in New Zealand: The Haka Party Incident and its Aftermath, 1979-1980 Canberra: Australian National University Peace Research Centre Monograph 2, 1988, 65 pp., n.p. p.b.

The mechanism whereby rat liver mitochondria regulate the extramitochondrial concentration of free Ca2+ was investigated. At 30°C and pH7.0, mitochondria can maintain a steady-state pCa2+0 (the negative logarithm of the free extramitochondrial Ca2+ concentration) of 6.1 (0.8μm). This represents a true steady state, as slight displacements in pCa2+0 away from 6.1 result in net Ca2+ uptake or efflux in order to restore pCa2+0 to its original value. In the absence of added permeant weak acid, the steady-state pCa2+0 is virtually independent of the Ca2+ accumulated in the matrix until 60nmol of Ca2+/mg of protein has been taken up. The steady-state pCa2+0 is also independent of the membrane potential, as long as the latter parameter is above a critical value. When the membrane potential is below this value, pCa2+0 is variable and appears to be governed by thermodynamic equilibration of Ca2+ across a Ca2+ uniport. Permeant weak acids increase, and N-ethylmaleimide decreases, the capacity of mitochondria to buffer pCa2+0 in the region of 6 (1μm-free Ca2+) while accumulating Ca2+. Permeant acids delay the build-up of the transmembrane pH gradient as Ca2+ is accumulated, and consequently delay the fall in membrane potential to values insufficient to maintain a pCa2+0 of 6. The steady-state pCa2+0 is affected by temperature, incubation pH and Mg2+. The activity of the Ca2+ uniport, rather than that of the respiratory chain, is rate-limiting when pCa2+0 is greater than 5.3 (free Ca2+ less than 5μm). When the Ca2+ electrochemical gradient is in excess, the activity of the uniport decreases by 2-fold for every 0.12 increase in pCa2+0 (fall in free Ca2+). At pCa2+0 6.1, the activity of the Ca2+ uniport is kinetically limited to 5nmol of Ca2+/min per mg of protein, even when the Ca2+ electrochemical gradient is large. A steady-state cycling of Ca2+ through independent influx and efflux pathways provides a model which is kinetically and thermodynamically consistent with the present observations, and which predicts an extremely precise regulation of pCa2+0 by liver mitochondria in vivo.

Nanomolar concentrations of charybdotoxin or dendrotoxin increase the cytoplasmic free Ca2+concentration in isolated central nerve terminals. The effects of the two toxins, normally considered to be blockers of K+channels controlled by voltage in a Ca2+‐sensitive or ‐insensitive manner, respectively, show only marginal additivity. Apamin, an inhibitor of low conductance Ca2+‐activated K+channels, was without effect in either the absence or presence of dendrotoxin. The effect of charybdotoxin on polarized, isolated central nerve terminals seems to be mediated largely by a block of K+channels sensitive to dendrotoxin. Apparently, these voltage‐operated K+channels make a more significant contribution to maintaining the polarized potential of synaptosomes than do those activated by Ca2+.

The mechanisms that establish the floral meristem are now becoming clearer, but the way in which flowering is maintained is less well understood. Impatiens balsamina provides a unique opportunity to address this question because reversion to vegetative growth can be obtained in a predictable way by transferring plants from inductive to non-inductive conditions. Following increasing amounts of induction, reversion takes place at progressively later stages of flower development. Partial flower induction and defoliation experiments show that a floral signal is produced in the cotyledon in response to inductive con-ditions and that this signal progressively diminishes after transfer to non-inductive conditions, during reversion. Therefore reversion in Impatiens is most likely due to the failure of leaves to become permanent sources of inductive signal in addition to the lack of meristem commitment to flowering. Analysis of the expression of the Impatiens homologues of the meristem identity genes floricaula and squamosa indicates that a change in floricaula transcription is not associated with the establishment or maintenance of the floral meristem in this species. Squamosa transcription is associated with floral development and petal initiation, and is maintained in existing petal or petaloid primordia even after the meristem has reverted. However, it is not expressed in the reverted meristem, in which leaves are initiated in whorled phyllotaxis and without axillary meristems, both characteristics usually associated with the floral meristem. These observations show that squamosa expression is not needed for the maintenance of these floral characters. The requirement for the production of the floral signal in the leaf during the process of flower development may reflect an additional function separate to that of squamosa activation; alternatively the signal may be required to ensure continued transcriptional activation in the meristem.

1. The specific activities for palmitoyl-CoA synthetase and for sn-glycerol 3-phosphate esterification, with palmitoyl-CoA generated either by the endogenous synthetase or from palmitoyl-(-)-carnitine, CoA and excess of carnitine palmitoyltransferase, were measured with rat liver mitochondria. 2. The mean specific activity of palmitoyl-CoA synthetase was approximately five- and seven-fold the rates of sn-glycerol 3-phosphate esterification from palmitate and palmitoyl-(-)-carnitine respectively. No significant correlation was found in different rats between the activities of palmitoyl-CoA synthetase and sn-glycerol 3-phosphate esterification from either acyl precursor. However, there was a significant correlation (r=0.83, P<0.001) between the rates of glycerolipid synthesis from palmitate and palmitoyl-(-)-carnitine. 3. The mean molar composition of the glycerolipid synthesized from palmitate was 58% lysophosphatidate, 31% phosphatidate and 11% neutral lipid. With palmitoyl-(-)-carnitine the equivalent values were 70, 23 and 7%, which were significantly different. 4. When palmitoyl-CoA synthetase had been inactivated by 60–70% after preincubation of mitochondria at 37°C, it became rate-limiting in glycerolipid biosynthesis. Additions of 1–5mm-ATP prevented inactivation of palmitoyl-CoA synthetase. 5. Preincubation also inhibited the oxidation of palmitate, palmitoyl-CoA, palmitoyl-(-)-carnitine and malate plus glutamate. These inhibitions could not be prevented by addition of ATP. 6. Diversion of palmitoyl-CoA to form palmitoyl-(-)-carnitine did not inhibit sn-glycerol 3-phosphate esterification. 7. The palmitoyl-CoA pool synthesized by the palmitoyl-CoA synthetase was augmented by adding partially purified synthetase or carnitine palmitoyltransferase and palmitoyl-(-)-carnitine. No stimulation of palmitate incorporation into glycerolipids occurred. 8. At low concentrations of Mg2+, palmitate, ATP and CoA the velocity with palmitoyl-CoA synthetase decreased more than that of glycerolipid synthesis from palmitate. 9. It is concluded that in the presence of optimum substrate concentrations the activity of sn-glycerol 3-phosphate acyltransferase and not of palmitoyl-CoA synthetase is rate-limiting in the synthesis of phosphatidate and lysophosphatidate in isolated rat liver mitochondria.

High‐resolution river modeling is valuable to study diurnal scale phytoplankton dynamics and understand biomass response to short‐term, rapid changes in its environmental controls. Based on theory contained in the Quality Evaluation and Simulation Tool for River‐systems model, a new river model is developed to simulate hourly scale phytoplankton growth and its environmental controls, thus allowing to study diurnal changes thereof. The model is implemented along a 62 km stretch in a lowland river, River Thames (England), using high‐frequency water quality measurements to simulate flow, water temperature, dissolved oxygen, nutrients, and phytoplankton concentrations for 2 years (2013–2014). The model satisfactorily simulates diurnal variability and transport of phytoplankton with Nash and Sutcliffe Efficiency (NSE) > 0.7 at all calibration sites. Even without high‐frequency data inputs, the model performs satisfactorily with NSE > 0.6. The model therefore can serve as a powerful tool both for predictive purposes and for hindcasting past conditions when hourly resolution water quality monitoring is unavailable. Model sensitivity analysis shows that the model with cool water diatoms as dominant species with an optimum growth temperature of 14°C performs the best for phytoplankton prediction. Phytoplankton blooms are mainly controlled by residence time, light and water temperature. Moreover, phytoplankton blooms develop within an optimum range of flow (21–63 m3s−1). Thus, lowering river residence time with short‐term high flow releases could help prevent major bloom developments. The hourly model improves biomass prediction and represents a step forward in high‐resolution phytoplankton modeling and consequently, bloom management in lowland river systems. Hourly model is developed for lowland river phytoplankton prediction and is tested in the River Thames using high‐frequency observationsBlooms are mainly influenced by physical controls and develop at low‐mid flows (21–63 m3s−1) and temperatures (11–18°C)High‐resolution modeling improves phytoplankton prediction in the river Hourly model is developed for lowland river phytoplankton prediction and is tested in the River Thames using high‐frequency observations Blooms are mainly influenced by physical controls and develop at low‐mid flows (21–63 m3s−1) and temperatures (11–18°C) High‐resolution modeling improves phytoplankton prediction in the river

In this paper we examine the Direct Method for measuring electron temperatures in H iiregions, and the extent to which such measurements can provide meaningful information on the physical conditions in these regions. We discuss the limits to what can be inferred about electron temperatures from nebular emission line fluxes. We provide a new simplified method for estimating electron temperatures, including parameters that can be used to determine this from UV [O iii] and [O ii] oxygen lines observable in high-redshift objects using ground-based telescopes. We test this method on published UV high redshift observations and compare the results with reported electron temperatures.

Brown fat mitochondria can short-circuit their respiratory chain to generate heat.

A list is presented of strategies for having successful international online sales, which includes choosing the right established marketplace such as eBay and Amazon, adhering to laws and regulations, and encourage customer retention through social media.