Further investigation on pockets of quiet within historical city centres: the case of widenings

Making available quiet zones for the urban population is a key factor to offer them the possibility to have restorative experiences and relief from stressful city life. Although these zones are often associated with vast green parks, the latter are usually located outside or far from cities' centres. Moreover, if we consider the case of historical city centres, they are almost absent. In previous research, we have focused on searching for alternative quiet spaces that inhabitants and tourists could use as a temporary refuge from urban noise and chaos. In these studies, we have shown that thanks to their acoustics peculiarities and several other non-acoustic characteristics, the cloisters and the courts of historic buildings have a high potential to induce restoration. Nevertheless, among the narrow streets of the historic cities centres, the widenings can also provide a small contribution to a temporary restoration of people. This paper investigates the restorative potentiality of these further spaces and compares the outcomes carried out from binaural recordings and in situ interviews with those of cloisters and courts of historic buildings within the ancient city centre of Naples.

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Città storica e sostenibilità / Historic Cities and Sustainability

10.36253/978-88-6655-305-2 ◽

2012 ◽

Keyword(s):

Cultural Heritage ◽

Building Materials ◽

Existing Buildings ◽

Architectural Heritage ◽

Open Spaces ◽

Ancient City ◽

Old City ◽

Historic Cities ◽

City Centres ◽

Very High

A subject that is inexplicably little studied at present, or indeed not at all, is that of the quest for possible applications and feasible objectives in the energy requalification of existing buildings, existing or planned open spaces, old city centres and the monumental and diffuse cultural heritage. At the present time it is crucial that the issues, research and techniques linked to the possibilities of an aware use of energy are applied to the old city centres and the existing heritage. This must start from a knowledge and investigation of the traditional building materials and techniques, which are in themselves inherently sustainable (comprising both the ancient city and the consolidated modern city and their historic stratifications). The historic environment indeed represents an infinite cultural and environmental resource and a very high percentage of the global architectural heritage.

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A geometallurgical characterization study of the Crystalkop Reef at the Great Noligwa Mine, Klerksdorp Goldfield, South Africa

South African Journal of Geology ◽

10.25131/gssajg.120.3.303 ◽

2017 ◽

Vol 120 (3) ◽

pp. 303-322

Author(s):

D. Pienaar ◽

B.M. Guy ◽

C. Pienaar ◽

K.S. Viljoen

Keyword(s):

South Africa ◽

Treatment Plant ◽

Processing Parameters ◽

Processing Plant ◽

Small Contribution ◽

Gold Cyanide ◽

Three Samples ◽

Characterization Study ◽

Different Sources

Abstract Mineralogical and textural variability of ores from different sources commonly leads to processing inefficiencies, particularly when a processing plant is designed to treat ore from a single source (i.e. ore of a relatively uniform composition). The bulk of the Witwatersrand ore in the Klerksdorp goldfield, processed at the AngloGold Ashanti Great Noligwa treatment plant, is derived from the Vaal Reef (>90%), with a comparatively small contribution obtained from the Crystalkop Reef (or C-Reef). Despite the uneven contribution, it is of critical importance to ensure that the processing parameters are optimized for the treatment of both the Vaal and C-Reefs. This paper serves to document the results of a geometallurgical study of the C-Reef at the Great Noligwa gold mine in the Klerksdorp goldfield of South Africa, with the primary aim of assessing the suitability of the processing parameters that are in use at the Great Noligwa plant. The paper also draws comparisons between the C-Reef and the Vaal Reef A-facies (Vaal Reef) and attempts to explain minor differences in the recovery of gold and uranium from these two sources. Three samples of the C-Reef were collected in-situ from the underground operations at Great Noligwa mine for mineralogical analyses and metallurgical tests. Laboratory-scale leach tests for gold (cyanide) and uranium (sulphuric acid) were carried out using dissolution conditions similar to that in use at the Great Noligwa plant, followed by further diagnostic leaching in the case of gold. The gold in the ore was found to be readily leachable with recoveries ranging from 95% to 97% (as opposed to 89% to 93% for the Vaal Reef). Additional recoveries were achieved in the presence of excess cyanide (96% to 98%). The recovery of uranium varied between 72% and 76% (as opposed to 30% to 64% for the Vaal Reef), which is substantially higher than predicted, given the amount of brannerite in the ore, which is generally regarded as refractory. Thus, the higher uranium recoveries from the C-Reef imply that a proportion of the uranium was recovered by the partial dissolution of brannerite. As the Vaal Reef contain high amounts of chlorite (3% to 8%), which is an important acid consumer, it is considered likely that this could have reduced the effectiveness of the H2SO4 leach in the case of the ore of the Vaal Reef. Since the gold and uranium recoveries from the C-Reef were higher than the recoveries from the Vaal Reef, the results demonstrate that the processing parameters used for treatment of the Vaal Reef are equally suited to the treatment of the C-Reef. Moreover, small processing modifications, such as increased milling and leach retention times, may well increase the recovery of gold (particularly when e.g. coarse gold, or unexposed gold, is present).

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Competition between Metals for Binding to Methanobactin Enables Expression of Soluble Methane Monooxygenase in the Presence of Copper

Applied and Environmental Microbiology ◽

10.1128/aem.03151-14 ◽

2014 ◽

Vol 81 (3) ◽

pp. 1024-1031 ◽

Cited By ~ 16

Author(s):

Bhagyalakshmi Kalidass ◽

Muhammad Farhan Ul-Haque ◽

Bipin S. Baral ◽

Alan A. DiSpirito ◽

Jeremy D. Semrau

Keyword(s):

Methane Monooxygenase ◽

High Specificity ◽

Copper Uptake ◽

Content Type ◽

Soluble Methane Monooxygenase ◽

Sds Page ◽

Genes Encoding ◽

Key Factor ◽

Membrane Bound

ABSTRACTIt is well known that copper is a key factor regulating expression of the two forms of methane monooxygenase found in proteobacterial methanotrophs. Of these forms, the cytoplasmic, or soluble, methane monooxygenase (sMMO) is expressed only at low copper concentrations. The membrane-bound, or particulate, methane monooxygenase (pMMO) is constitutively expressed with respect to copper, and such expression increases with increasing copper. Recent findings have shown that copper uptake is mediated by a modified polypeptide, or chalkophore, termed methanobactin. Although methanobactin has high specificity for copper, it can bind other metals, e.g., gold. Here we show that inMethylosinus trichosporiumOB3b, sMMO is expressed and active in the presence of copper if gold is also simultaneously present. Such expression appears to be due to gold binding to methanobactin produced byM. trichosporiumOB3b, thereby limiting copper uptake. Such expression and activity, however, was significantly reduced if methanobactin preloaded with copper was also added. Further, quantitative reverse transcriptase PCR (RT-qPCR) of transcripts of genes encoding polypeptides of both forms of MMO and SDS-PAGE results indicate that both sMMO and pMMO can be expressed when copper and gold are present, as gold effectively competes with copper for binding to methanobactin. Such findings suggest that under certain geochemical conditions, both forms of MMO may be expressed and activein situ. Finally, these findings also suggest strategies whereby field sites can be manipulated to enhance sMMO expression, i.e., through the addition of a metal that can compete with copper for binding to methanobactin.

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Integrative analysis of <i>Geobacter</i> spp. and sulfate-reducing bacteria during uranium bioremediation

Biogeosciences ◽

10.5194/bg-9-1033-2012 ◽

2012 ◽

Vol 9 (3) ◽

pp. 1033-1040 ◽

Cited By ~ 25

Author(s):

M. Barlett ◽

K. Zhuang ◽

R. Mahadevan ◽

D. Lovley

Keyword(s):

Sulfate Reducing Bacteria ◽

Field Trials ◽

Second Phase ◽

Sulfate Reducing ◽

Organic Electron ◽

Poor Understanding ◽

Key Factor ◽

Reducing Bacteria ◽

The Impact

Abstract. Enhancing microbial U(VI) reduction with the addition of organic electron donors is a promising strategy for immobilizing uranium in contaminated groundwaters, but has yet to be optimized because of a poor understanding of the factors controlling the growth of various microbial communities during bioremediation. In previous field trials in which acetate was added to the subsurface, there were two distinct phases: an initial phase in which acetate-oxidizing, U(VI)-reducing Geobacter predominated and U(VI) was effectively reduced and a second phase in which acetate-oxidizing sulfate reducing bacteria (SRB) predominated and U(VI) reduction was poor. The interaction of Geobacter and SRB was investigated both in sediment incubations that mimicked in situ bioremediation and with in silico metabolic modeling. In sediment incubations, Geobacter grew quickly but then declined in numbers as the microbially reducible Fe(III) was depleted whereas the SRB grow more slowly and reached dominance after 30–40 days. Modeling predicted a similar outcome. Additional modeling in which the relative initial percentages of the Geobacter and SRB were varied indicated that there was little to no competitive interaction between Geobacter and SRB when acetate was abundant. Further simulations suggested that the addition of Fe(III) would revive the Geobacter, but have little to no effect on the SRB. This result was confirmed experimentally. The results demonstrate that it is possible to predict the impact of amendments on important components of the subsurface microbial community during groundwater bioremediation. The finding that Fe(III) availability, rather than competition with SRB, is the key factor limiting the activity of Geobacter during in situ uranium bioremediation will aid in the design of improved uranium bioremediation strategies.

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Marketplaces and central spaces: markets and the rise of competing spatial ideals in Danish city centres, c. 1850–1900

Urban History ◽

10.1017/s0963926815000218 ◽

2015 ◽

Vol 43 (3) ◽

pp. 372-390 ◽

Cited By ~ 1

Author(s):

JENS TOFTGAARD

Keyword(s):

Nineteenth Century ◽

Urban Space ◽

Capital Investment ◽

City Centre ◽

Fish Market ◽

Open Air Markets ◽

The City ◽

City Centres

ABSTRACTThe traditional open-air markets on the central squares of Danish cities were thriving in the middle of the nineteenth century. However, the markets were soon challenged by new urban ideals of the city centre as a place for shopping and capital investment. At the same time, urban reformers made efforts to improve the market trade to meet modern standards. The rivalling interests struggled over the question of modernization or relocation of the central square markets and ultimately the definition and use of the central urban space. In particular, this article will examine the struggle over the construction of a fish market hall in Odense as it serves to reveal the different conceptions of the central urban space that affected the fate of the street markets.

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In situ acoustic analysis of two twentieth-century heritage carillons

Heritage Science ◽

10.1186/s40494-021-00482-8 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Scott Allan Orr

Keyword(s):

Twentieth Century ◽

Acoustic Analysis ◽

Mechanical Action ◽

Ex Situ ◽

Physical Acoustics ◽

Acoustic Characteristics ◽

Dynamic Level ◽

Significant Difference ◽

And Function

AbstractCarillons are a diverse and global form of musical and civic heritage: musical instruments comprised of a series of 23 or more bells, typically hung in a tower-like structure, tuned chromatically and played from a touch-sensitive manual and pedal console using an elaborate mechanical action. Carillon bells have a distinct series of musical overtones which should be accurately tuned to one another and with other bells they sound alongside. Although these overtones have been previously studied ex situ, this study assesses the acoustic characteristics of two early-twentieth century carillons in Toronto, Canada as a combination of structure, bells, and mechanical action. Thus, the instrument and its context are considered holistically, more accurately reflecting the musical sensitivity of a carillonist. Spectral analysis of audio samples of each bell at different musical dynamic levels enabled the analysis of the acoustic qualities of the bells and the mechanical action of the instruments. The tuning of bells in the instruments varied; most importantly, there was a significant difference between the audial intensity of the bell tones produced by the instruments, demonstrating the importance of the mechanical action as part of the ‘carillon system’. This was represented with a resistive power-law model, that represents the sensitivity of intensity to carillonist musical dynamic level. A discussion of the implications for artistic and heritage practice follows. Understanding the in situ physical acoustics of the carillon as a holistic instrument in its context informs performers, arrangers, and composers of how they can best embrace the instrument’s unique qualities to improve artistic pursuits and support the appreciation of carillons as heritage instruments and function as civic voices.

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A Novel Method to Determine the Drilling Fluid Density for Gypsum-Salt Layer

10.2118/208099-ms ◽

2021 ◽

Author(s):

Jitong Liu ◽

Wanjun Li ◽

Haiqiu Zhou ◽

Yixin Gu ◽

Fuhua Jiang ◽

...

Keyword(s):

Drilling Fluid ◽

In Situ Stress ◽

Wellbore Stability ◽

Shrinkage Rate ◽

Fluid Density ◽

Salt Layer ◽

Rock Creep ◽

Key Factor ◽

Well Abandonment

Abstract The reservoir underneath the salt bed usually has high formation pressure and large production rate. However, downhole complexities such as wellbore shrinkage, stuck pipe, casing deformation and brine crystallization prone to occur in the drilling and completion of the salt bed. The drilling safety is affected and may lead to the failure of drilling to the target reservoir. The drilling fluid density is the key factor to maintain the salt bed’s wellbore stability. The in-situ stress of the composite salt bed (gypsum-salt -gypsum-salt-gypsum) is usually uneven distributed. Creep deformation and wellbore shrinkage affect each other within layers. The wellbore stability is difficult to maintain. Limited theorical reference existed for drilling fluid density selection to mitigate the borehole shrinkage in the composite gypsum-salt layers. This paper established a composite gypsum-salt model based on the rock mechanism and experiments, and a safe-drilling density selection layout is formed to solve the borehole shrinkage problem. This study provides fundamental basis for drilling fluid density selection for gypsum-salt layers. The experiment results show that, with the same drilling fluid density, the borehole shrinkage rate of the minimum horizontal in-situ stress azimuth is higher than that of the maximum horizontal in-situ stress azimuth. However, the borehole shrinkage rate of the gypsum layer is higher than salt layer. The hydration expansion of the gypsum is the dominant reason for the shrinkage of the composite salt-gypsum layer. In order to mitigate the borehole diameter reduction, the drilling fluid density is determined that can lower the creep rate less than 0.001, as a result, the borehole shrinkage of salt-gypsum layer is slowed. At the same time, it is necessary to improve the salinity, filter loss and plugging ability of the drilling fluid to inhibit the creep of the soft shale formation. The research results provide technical support for the safe drilling of composite salt-gypsum layers. This achievement has been applied to 135 wells in the Amu Darya, which completely solved the of wellbore shrinkage problem caused by salt rock creep. Complexities such as stuck string and well abandonment due to high-pressure brine crystallization are eliminated. The drilling cycle is shortened by 21% and the drilling costs is reduced by 15%.

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ATP depletion and mitochondrial functional loss during ischemia in slow and fast heart-rate hearts

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1990.259.6.h1759 ◽

1990 ◽

Vol 259 (6) ◽

pp. H1759-H1766 ◽

Cited By ~ 5

Author(s):

W. Rouslin ◽

C. W. Broge ◽

I. L. Grupp

Keyword(s):

Mitochondrial Function ◽

Atp Depletion ◽

Mitochondrial Atpase ◽

Small Contribution ◽

Bicarbonate Buffer ◽

Tissue Ph ◽

Atp Production ◽

Dog Heart ◽

Rat Hearts

In the present study, isolated dog and rat hearts were perfused in the Langendorff mode with Krebs bicarbonate buffer in the absence and presence of 10(-5) M oligomycin. The perfusion protocols employed allowed tissue pH to drop during subsequent ischemic incubations essentially as it would in blood-perfused hearts. Tissue pH, ATP, lactate, and mitochondrial respiratory function were measured during the course of subsequent zero-flow ischemic incubations. The adenosinetriphosphatase (ATPase) activities attributable to both mitochondrial and nonmitochondrial ATPases in sonicated heart homogenates and the actomyosin ATPase in isolated cardiac myofibrils were measured in both species. Consistent with earlier results with a different model in which tissue pH was buffered during the ischemic incubations [W. Rouslin, J. L. Erickson, and R. J. Solaro. Am. J. Physiol. 250 (Heart Circ. Physiol. 19): H503-H508, 1986], the inhibition of the mitochondrial ATPase in situ by oligomycin markedly slowed both tissue ATP depletion and the loss of mitochondrial function during ischemia in the dog. However, oligomycin had only a very small and transient effect on ATP depletion and mitochondrial function in the rat. This was apparently so because of the fivefold higher rate of glycolytic ATP production as well as the nearly threefold higher total nonmitochondrial ATPase activity of ischemic rat compared with ischemic dog heart. These results suggest that although the inhibition of the mitochondrial ATPase makes a major contribution to ATP conservation in ischemic dog heart, it makes only a very small contribution in rat.

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“LEAGUE OF HISTORICAL CITIES” AS A TOURIST POTENTIAL REPRESENTATION FORMAT OF THE WORLD’S CITIES

Service & Tourism Current Challenges ◽

10.22412/1995-0411-2017-11-2-17-27 ◽

2017 ◽

Vol 11 (2) ◽

pp. 17-27 ◽

Cited By ~ 1

Author(s):

Олег Афанасьев ◽

Oleg Afanasev

Keyword(s):

Urban Planning ◽

Marketing Strategy ◽

International Organizations ◽

World Market ◽

Governmental Organization ◽

City Life ◽

Cultural Organizations ◽

The World ◽

Historic Cities ◽

Potential Representation

The article considers the category of the «historical city», the formation features of this concept in time, the main problems and contradictions associated with the corresponding status for cities. The author substantiates the importance of participation of historical cities in various international organizations performing representative functions for them. This makes it possible to inform large number of potential tourists about the historical and cultural potential of historic cities. The article describes the international non-governmental organization League of Historical Cities (LIG), its goals, tasks, and the geography of member cities, and proposes their classification according to the spatial and-time principle. Increasing tourist fame (representativeness) in the world and the opportunities provided by LIG for information promotion is the reason for cities from different countries to desire for membership in this organization. Many historical cities of Russia, especially small and medium-sized, retain in their environment authentic stories and legends, architectural monuments, often have unique features of landscape and urban planning. Each settlement also has its own specific dates related to the outstanding events of city life. And the involvement of at least some of them in the activities of international historical and cultural organizations, for example, the League and its analogies, can be considered as world recognition. This should be regarded as one of the marketing strategy mechanisms of the city’spromotion, and its active positioning in the world market of tourist offers.

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