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Purpose: Current treatment of acromegaly restores a normal life expectancy in most cases. So, the study of persistent complications affecting patients’ quality of life (QoL) is of paramount importance, especially motor disability and depression. In a large cohort of acromegalic patients we aimed at establishing the prevalence of depression, to look for clinical and sociodemographic factors associated with it, and to investigate the respective roles (and interactions) of depression and arthropathy in influencing QoL. Methods: One hundred and seventy-one acromegalic patients (95 women and 76 men, aged 20–85 years) among those recruited in a cross-sectional Italian multicentric study were investigated. Each patient filled in three validated questionnaires: AcroQoL, WOMAC (measuring articular pain, stiffness and functionality), and AIMS (evaluating articular symptoms and depression). Results: A very high (up to 28%) depression rate was detected in acromegalic subjects. Two patients showing pathological AIMS depression scores, committed suicide during the three years observational period. In our population poor psychological status was significantly associated with female sex. Furthermore, a significant strong correlation was found between AIMS depression score and WOMAC score. Both depression and arthropathy-related motor disability turned out to independently contribute with similar strength to the impairment of QoL. Conclusions: We report a high prevalence of depression in acromegaly, which is associated with female sex and arthropathy. Both depression and arthropathy strongly and independently contribute to the impaired QoL of patients. Our study shows that assessment and monitoring of psychological status is mandatory in acromegaly, also suggesting an inexpensive tool for this assessment.

The countries of central Africa (20 contiguous countries excluding West and South Africa) cover a very large and intensely mineralised area of central Gondwana, and differ enormously in size, history, infrastructure, geological information, mineral potential and political risk to investment. Those on the Atlantic seaboard (Zaire, Angola and Namibia) are more richly endowed with known resources than those on the Indian seaboard. However, the latter offer significant potential for mineral sands, coal, industrial minerals and geothermal energy. Tables show, on a comparative basis, the main mineral characteristics of these countries. The case is made for the development of medium sized mines which are very well suited for the sustainable development of central Africa. Priority targets appear to be precious metals, medium-tonnage base metal deposits and non-metallics., The countries of central Africa (20 contiguous countries excluding West and South Africa) cover a very large and intensely mineralised area of central Gondwana, and differ enormously in size, history, infrastructure, geological information, mineral potential and political risk to investment. Those on the Atlantic seaboard (Zaire, Angola and Namibia) are more richly endowed with known resources than those on the Indian seaboard. However, the latter offer significant potential for mineral sands, coal, industrial minerals and geothermal energy. Tables show, on a comparative basis, the main mineral characteristics of these countries. The case is made for the development of medium sized mines which are very well suited for the sustainable development of central Africa. Priority targets appear to be precious metals, medium-tonnage base metal deposits and non-metallics.

Small uranium deposits can be successfully exploited as the product has high unit value and low volume, the technology required is conventional, the occurrence of several small deposits in a mineralised district permits centralised processing, and the prospects of large, longer-term projects are uncertain. The future for uranium demand and its existing availability are reviewed and the potential of the various geological environments in which uranium occurs for small-scale deposits is assessed. Costs of exploration, mining and milling are discussed; costs estimates are given., Small uranium deposits can be successfully exploited as the product has high unit value and low volume, the technology required is conventional, the occurrence of several small deposits in a mineralised district permits centralised processing, and the prospects of large, longer-term projects are uncertain. The future for uranium demand and its existing availability are reviewed and the potential of the various geological environments in which uranium occurs for small-scale deposits is assessed. Costs of exploration, mining and milling are discussed; costs estimates are given.

Uranium mineralisation is present in both igneous and sedimentary environments. Viable deposits of uranothorianite have been partially worked. These consist of lenses of uranothorianite occurring in pyroxenite. Pegmatites, occasionally uraniferous, are widespread throughout the crystalline basement of the island, but offer only a mediocre economic potential. Thorium is present in economic quantities on the southeast coast where it occurs in beach placers of monazite. Other radioactive mineralisations include occurrences of bastnaesite or pyrochlore in peralkaline intrusions., Uranium mineralisation is present in both igneous and sedimentary environments. Viable deposits of uranothorianite have been partially worked. These consist of lenses of uranothorianite occurring in pyroxenite. Pegmatites, occasionally uraniferous, are widespread throughout the crystalline basement of the island, but offer only a mediocre economic potential. Thorium is present in economic quantities on the southeast coast where it occurs in beach placers of monazite. Other radioactive mineralisations include occurrences of bastnaesite or pyrochlore in peralkaline intrusions.

Both geological and economic aspects of uranium exploitation render it suitable for small-scale operations. The uncertain long term future of its demand means that conventional short term projects are less of a risk than long term, capital-intensive ones. Uranium is often found as small deposits which cannot be exploited by large-scale methods; it is currently mined on a small scale as the technology required is conventional. Uranium, most of which is currently mined in developed countries, is thought to exist in less developed countries including small deposits which can be developed with a minimum of economic and technological dependence on other countries. The search for first-generation deposits can be carried out by small units with little expenditure., Both geological and economic aspects of uranium exploitation render it suitable for small-scale operations. The uncertain long term future of its demand means that conventional short term projects are less of a risk than long term, capital-intensive ones. Uranium is often found as small deposits which cannot be exploited by large-scale methods; it is currently mined on a small scale as the technology required is conventional. Uranium, most of which is currently mined in developed countries, is thought to exist in less developed countries including small deposits which can be developed with a minimum of economic and technological dependence on other countries. The search for first-generation deposits can be carried out by small units with little expenditure.

The Madadzang uranium occurrence is situated about 250 km SSW or N'djamena at only 5 km from the Cameroon border. Tectonically the occurrence is located close to the eastern arm of the Benue Trough and it lies within a well-defined intrusion of alkaline granite. Two uranium occurrences at a distance of 7 km from each other have been recognized but only the southern one, Madadzang, has been investigated so far. The uranium mineralisation consists of autunite at surface, and uraninite, Y-rich-coffinite and kasolite at depth. Some sulphides are present. Thorium is very low in all mineral phases but yttrium is unusually high. Two inclined reconnaissance drill holes have intersected 20 and 29 m of mineralisation, assaying more than 700 ppm U, the maximum value being 0.95% U over 1.3m. The Madadzang prospect consists of an essentially subvertical uranium mineralisation of primary uraninite and uranium silicates probably of hydrothermal origin, in a homogenous but fractured alkaline intrusion. The mineralisation is occasionally expressed in highly mineralised veinlets probably structurally controlled. A possible metallogenic relationship between the mineralisation and the Benue aulacogen is suggested. Both the vertical and the laterial extension of the mineralisation are still untested., The Madadzang uranium occurrence is situated about 250 km SSW or N'djamena at only 5 km from the Cameroon border. Tectonically the occurrence is located close to the eastern arm of the Benue Trough and it lies within a well-defined intrusion of alkaline granite. Two uranium occurrences at a distance of 7 km from each other have been recognized but only the southern one, Madadzang, has been investigated so far. The uranium mineralisation consists of autunite at surface, and uraninite, Y-rich-coffinite and kasolite at depth. Some sulphides are present. Thorium is very low in all mineral phases but yttrium is unusually high. Two inclined reconnaissance drill holes have intersected 20 and 29 m of mineralisation, assaying more than 700 ppm U, the maximum value being 0.95% U over 1.3m. The Madadzang prospect consists of an essentially subvertical uranium mineralisation of primary uraninite and uranium silicates probably of hydrothermal origin, in a homogenous but fractured alkaline intrusion. The mineralisation is occasionally expressed in highly mineralised veinlets probably structurally controlled. A possible metallogenic relationship between the mineralisation and the Benue aulacogen is suggested. Both the vertical and the laterial extension of the mineralisation are still untested.

China's considerable tin resources will play a subordinate but important role in the development of the Chinese mining industry. The recently developed Dachang deposit is one of the most promising tin deposit in China and belongs to the large-tonnage hard-rock type deposit suitable for bulk underground mining methods. China's tin ores are mainly of the cassiterite type and are iron rich. Separation by fuming techniques are the main methods of recovery with iron being left in the slags. Important by-products include Zn, Ag, Sb, Nb, Ta. The largest mine of the Dachang tinfield is on the Tongkien-Changpo orebody, and is mined by stoping. Ore is hoisted to the surface by two main vertical shafts. Concentration of the ore is by milling, gravity or flotation methods and shaking tables., China's considerable tin resources will play a subordinate but important role in the development of the Chinese mining industry. The recently developed Dachang deposit is one of the most promising tin deposit in China and belongs to the large-tonnage hard-rock type deposit suitable for bulk underground mining methods. China's tin ores are mainly of the cassiterite type and are iron rich. Separation by fuming techniques are the main methods of recovery with iron being left in the slags. Important by-products include Zn, Ag, Sb, Nb, Ta. The largest mine of the Dachang tinfield is on the Tongkien-Changpo orebody, and is mined by stoping. Ore is hoisted to the surface by two main vertical shafts. Concentration of the ore is by milling, gravity or flotation methods and shaking tables.

Discussion is presented of sub-Saharan Africa and its potential as a future major gold producer. Exploration is likely to entail searching for types of gold deposits that were unknown only 20 years ago, and will make use of advanced techniques which have been successful in deeply weathered or sand-covered areas of Australia. Modern airborne geophysics coupled with satellite imagery should give good results, particularly if used in conjunction with inexpensive satellite positioning systems on the ground. Ultrasensitive geochemical methods could also be useful. Problems could include political fragmentation, corruption, a lack of suitable personnel, lack of geological information, the number of small-scale miners, military activity and offering security deals in return for mining titles. Five areas have been identified as having very good potential: the Kalahari basin, the Madagascar-northern Mozambique area, the west Nile craton, the Eritrea-Ethiopia-Sudan region and the Mauritania-Senegal area., Discussion is presented of sub-Saharan Africa and its potential as a future major gold producer. Exploration is likely to entail searching for types of gold deposits that were unknown only 20 years ago, and will make use of advanced techniques which have been successful in deeply weathered or sand-covered areas of Australia. Modern airborne geophysics coupled with satellite imagery should give good results, particularly if used in conjunction with inexpensive satellite positioning systems on the ground. Ultrasensitive geochemical methods could also be useful. Problems could include political fragmentation, corruption, a lack of suitable personnel, lack of geological information, the number of small-scale miners, military activity and offering security deals in return for mining titles. Five areas have been identified as having very good potential: the Kalahari basin, the Madagascar-northern Mozambique area, the west Nile craton, the Eritrea-Ethiopia-Sudan region and the Mauritania-Senegal area.

Transparency International, a German-based anti-corruption agency, have produced a corruption perception index which represents the level at which corruption is perceived by people working for multinational companies in various countries. Data is taken from executives stationed overseas, embassies, chambers of commerce, various risk research agencies and universities. A plot is presented of the TI corruption index against GNP for each country. There is a strong correlation between a country's GNP and its corruption index with the poorest countries scoring highest on perceived corruption. A strong mining industry does not seem to affect corruption either way., Transparency International, a German-based anti-corruption agency, have produced a corruption perception index which represents the level at which corruption is perceived by people working for multinational companies in various countries. Data is taken from executives stationed overseas, embassies, chambers of commerce, various risk research agencies and universities. A plot is presented of the TI corruption index against GNP for each country. There is a strong correlation between a country's GNP and its corruption index with the poorest countries scoring highest on perceived corruption. A strong mining industry does not seem to affect corruption either way.

The price of tin is at historically low levels and tin is in oversupply. Present production is largely from alluvial deposits worked mainly by small- and medium-sized producers. These producers, often undercapitilised and working deposits of declining grade, are faced with rising production costs. It is expected that many will cease production in the future. Interest is therefore beginning to focus on the viability of exploiting large hard-rock tin deposits amenable to low-cost bulk mining methods. Among the countries which appear to have very large reserves of hard-rock tin deposits is China, and it is anticipated that in the future China will emerge as a major supplier., The price of tin is at historically low levels and tin is in oversupply. Present production is largely from alluvial deposits worked mainly by small- and medium-sized producers. These producers, often undercapitilised and working deposits of declining grade, are faced with rising production costs. It is expected that many will cease production in the future. Interest is therefore beginning to focus on the viability of exploiting large hard-rock tin deposits amenable to low-cost bulk mining methods. Among the countries which appear to have very large reserves of hard-rock tin deposits is China, and it is anticipated that in the future China will emerge as a major supplier.

In 1997, Australia and Africa accounted for 17% each of total mineral exploration expenditure, around 66% of which was directed towards primary gold deposits. Over 75 Australian mining companies are operating in more than 30 African countries. It is now easy to operate in Africa, but not as easy to be successful. All major African countries are listed with factual data on population, GDP, military risk, the presence of a recent mining code, mineral production in 1998 and the number of Australian companies operating. Details are also presented of specific Australian companies operating in Africa. Some signs are now occurring, however, which could imply that investment opportunities are decreasing: exhausting of gold and diamond artisanal workings, a new business-oriented African elite, the emerging African stock exchanges and the development of an increasingly vigorous African mining sector comparable to that of Australia or Canada., In 1997, Australia and Africa accounted for 17% each of total mineral exploration expenditure, around 66% of which was directed towards primary gold deposits. Over 75 Australian mining companies are operating in more than 30 African countries. It is now easy to operate in Africa, but not as easy to be successful. All major African countries are listed with factual data on population, GDP, military risk, the presence of a recent mining code, mineral production in 1998 and the number of Australian companies operating. Details are also presented of specific Australian companies operating in Africa. Some signs are now occurring, however, which could imply that investment opportunities are decreasing: exhausting of gold and diamond artisanal workings, a new business-oriented African elite, the emerging African stock exchanges and the development of an increasingly vigorous African mining sector comparable to that of Australia or Canada.

The need for uranium exploration by LDCs (less developed countries) is often questioned and the arguments in favour are therefore outlined. Certain features of uranium are peculiar to it rather than other minerals: the fluctuating demand - uncertain in the long term, that large resources in the LDCs await discovery, that initial prospecting is relatively cheap and easy, and that small deposits are of considerable economic interest. The options for governments in evolving policies to encourage development of uranium resources are discussed. Recommendations for the stages of exploration and for a range of suitable techniques for different scales from regional reconnaissance to prospect scale are made, and the differences between strategies appropriate to developed countries and LDCs are pointed out. The level of exploration of the uranium resources of a number of developing countries is reviewed briefly., The need for uranium exploration by LDCs (less developed countries) is often questioned and the arguments in favour are therefore outlined. Certain features of uranium are peculiar to it rather than other minerals: the fluctuating demand - uncertain in the long term, that large resources in the LDCs await discovery, that initial prospecting is relatively cheap and easy, and that small deposits are of considerable economic interest. The options for governments in evolving policies to encourage development of uranium resources are discussed. Recommendations for the stages of exploration and for a range of suitable techniques for different scales from regional reconnaissance to prospect scale are made, and the differences between strategies appropriate to developed countries and LDCs are pointed out. The level of exploration of the uranium resources of a number of developing countries is reviewed briefly.

The four proposed models and submodels of large, hard rock, tin deposits focus on basic concepts such as the spatial relationship with tin granites, depth of emplacements and the level of erosion. General concepts are drawn. Modelling is reviewed not only in its geological and exploration aspects but also in its mining and economic implications., The four proposed models and submodels of large, hard rock, tin deposits focus on basic concepts such as the spatial relationship with tin granites, depth of emplacements and the level of erosion. General concepts are drawn. Modelling is reviewed not only in its geological and exploration aspects but also in its mining and economic implications.

Eritrea is the newest country in Africa (independence from Ethiopia was declared in May 1993) and the country's mineral endowment is seen as a major factor in its future. Offshore oil potential is considered to be high. Vast areas offer attractive gold potential and a mineral exploration programme with emphasis on gold began in January 1994. The potential for iron is mediocre, but there is good potential for copper and other base metals and chrome has been reported in western Eritrea. An excellent potential exists for potash and there is small, but significant, production of bricks, glass, cement, salt and dimension stone., Eritrea is the newest country in Africa (independence from Ethiopia was declared in May 1993) and the country's mineral endowment is seen as a major factor in its future. Offshore oil potential is considered to be high. Vast areas offer attractive gold potential and a mineral exploration programme with emphasis on gold began in January 1994. The potential for iron is mediocre, but there is good potential for copper and other base metals and chrome has been reported in western Eritrea. An excellent potential exists for potash and there is small, but significant, production of bricks, glass, cement, salt and dimension stone.

Mining is Namibia's largest industry, accounting for 22% of the country's gross domestic product in 1991. A review is presented of Namibia's mineral endowment. This covers diamonds, base metals, uranium, gold, tin, tungsten, tantalum, columbium, lithium, beryllium, caesium, graphite, fluorspar, wollastonite, dimension stone, semi-precious stones and hydrocarbons., Mining is Namibia's largest industry, accounting for 22% of the country's gross domestic product in 1991. A review is presented of Namibia's mineral endowment. This covers diamonds, base metals, uranium, gold, tin, tungsten, tantalum, columbium, lithium, beryllium, caesium, graphite, fluorspar, wollastonite, dimension stone, semi-precious stones and hydrocarbons.

Namibia's semi-arid climate and generally flat morphology make the country well suited to mineral exploration. About 40% of the country presents abundant outcrops and the rest is buried under the Kalahari sands. Mining is Namibia's single largest industry. It accounted for 22% of its GDP in 1991. The country's industrial base and infrastructure have been untouched by war and the ruling party, SWAPO, has embarked on a successful policy of reconciliation and economic development. Namibia produces 9.5% of the world's uranium and 6% of the world's gem-diamonds. It ranks among Africa's top four producers, also exporting copper, lead, zinc, cadmium, arsenic, antimony, lithium, silver, fluorspar, salt and a variety of non metallics. There are huge reserves of these commodities. The following commodities are considered: diamonds, base metals, uranium, gold, graphite, fluorspar, wollastonite, dimension stone, semi-precious stones and hydrocarbons., Namibia's semi-arid climate and generally flat morphology make the country well suited to mineral exploration. About 40% of the country presents abundant outcrops and the rest is buried under the Kalahari sands. Mining is Namibia's single largest industry. It accounted for 22% of its GDP in 1991. The country's industrial base and infrastructure have been untouched by war and the ruling party, SWAPO, has embarked on a successful policy of reconciliation and economic development. Namibia produces 9.5% of the world's uranium and 6% of the world's gem-diamonds. It ranks among Africa's top four producers, also exporting copper, lead, zinc, cadmium, arsenic, antimony, lithium, silver, fluorspar, salt and a variety of non metallics. There are huge reserves of these commodities. The following commodities are considered: diamonds, base metals, uranium, gold, graphite, fluorspar, wollastonite, dimension stone, semi-precious stones and hydrocarbons.

Although Angola has been a producer of an unusually wide range of mineral commodities, the production has almost invariably been small. This, however, seems inconsistent with what is known of Angola's geology and that of its neighbours. Some of the political reasons for the nature of Angola's mineral industries are discussed. Mineral resources such as diamonds, iron, gold, base metals and ferroalloys and their exploitation in Angola are also discussed., Although Angola has been a producer of an unusually wide range of mineral commodities, the production has almost invariably been small. This, however, seems inconsistent with what is known of Angola's geology and that of its neighbours. Some of the political reasons for the nature of Angola's mineral industries are discussed. Mineral resources such as diamonds, iron, gold, base metals and ferroalloys and their exploitation in Angola are also discussed.

The industrial base of Vietnam is still modest and this acts as a limiting factor on the domestic consumption of industrial minerals. Vietnam possesses a number of industrial resources which, if properly processed and marketed, should prove successful in the international markets. Vietnam's proximity to Japan and the economies of the Pacific Basin is a powerful argument for the development of the production and export of its industrial minerals. Vietnam seems to have the geological and technical potential for producing at least some of the following commodities - high quality graphite, calcined alumina, moulding grade chromite, battery grade manganese, rare earth oxides, talc and zircon. The last two years have seen the enactment of new legislation and the dissemination of technical information as Vietnam tries to encourage the input of foreign technologies and capital into its economy., The industrial base of Vietnam is still modest and this acts as a limiting factor on the domestic consumption of industrial minerals. Vietnam possesses a number of industrial resources which, if properly processed and marketed, should prove successful in the international markets. Vietnam's proximity to Japan and the economies of the Pacific Basin is a powerful argument for the development of the production and export of its industrial minerals. Vietnam seems to have the geological and technical potential for producing at least some of the following commodities - high quality graphite, calcined alumina, moulding grade chromite, battery grade manganese, rare earth oxides, talc and zircon. The last two years have seen the enactment of new legislation and the dissemination of technical information as Vietnam tries to encourage the input of foreign technologies and capital into its economy.

According to the statistics of the General Department of Geology and Mining (GDGM), Vietnam produces only four metallic ores - iron, chromite, tin and gold. In reality, output is far more diversified although very small. Vietnam produces zinc, tungsten, antimony, titanium and zirconium and probably other minor metalliferous commodities. From what is known of its metallogeny and scant exploration data, Vietnam does possess a number of extremely interesting prospects. Some have been partially investigated and drilled by tha GDGM over the past 15 years, often with positive results. It should be remembered that Vietnam was a producer of tin, gold, silver, copper, zinc and lead long before the French colonial period. A balanced view of Vietnam's metalliferous prospects for potential investors is given., According to the statistics of the General Department of Geology and Mining (GDGM), Vietnam produces only four metallic ores - iron, chromite, tin and gold. In reality, output is far more diversified although very small. Vietnam produces zinc, tungsten, antimony, titanium and zirconium and probably other minor metalliferous commodities. From what is known of its metallogeny and scant exploration data, Vietnam does possess a number of extremely interesting prospects. Some have been partially investigated and drilled by tha GDGM over the past 15 years, often with positive results. It should be remembered that Vietnam was a producer of tin, gold, silver, copper, zinc and lead long before the French colonial period. A balanced view of Vietnam's metalliferous prospects for potential investors is given.

According to its own statistics, Vietnam produces only six mineral commodities: coal and lignite, phosphates, iron ore, gold, tin and graphite. In reality the production is much more diversified. Vietnam is also a producer of lead, zinc, antimony, pyrite, wolframite, manganese, kaolinite, limestone, marble, salt, a variety of non-metallics and precious stones. The industry is reviewed and the recent political changes are outlined., According to its own statistics, Vietnam produces only six mineral commodities: coal and lignite, phosphates, iron ore, gold, tin and graphite. In reality the production is much more diversified. Vietnam is also a producer of lead, zinc, antimony, pyrite, wolframite, manganese, kaolinite, limestone, marble, salt, a variety of non-metallics and precious stones. The industry is reviewed and the recent political changes are outlined.