The production of isobutanol in microorganisms has recently been achieved by harnessing the highly active 2-keto acid pathways. Since these 2-keto acids are precursors of amino acids, we aimed to ...construct an isobutanol production platform in Corynebacterium glutamicum, a well-known amino-acid-producing microorganism. Analysis of this host's sensitivity to isobutanol toxicity revealed that C. glutamicum shows an increased tolerance to isobutanol relative to Escherichia coli. Overexpression of alsS of Bacillus subtilis, ilvC and ilvD of C. glutamicum, kivd of Lactococcus lactis, and a native alcohol dehydrogenase, adhA, led to the production of 2.6 g/L isobutanol and 0.4 g/L 3-methyl-1-butanol in 48 h. In addition, other higher chain alcohols such as 1-propanol, 2-methyl-1-butanol, 1-butanol, and 2-phenylethanol were also detected as byproducts. Using longer-term batch cultures, isobutanol titers reached 4.0 g/L after 96 h with wild-type C. glutamicum as a host. Upon the inactivation of several genes to direct more carbon through the isobutanol pathway, we increased production by ∼25% to 4.9 g/L isobutanol in a ∆pyc∆ldh background. These results show promise in engineering C. glutamicum for higher chain alcohol production using the 2-keto acid pathways.
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CEKLJ, DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
This study investigated a double loop network operated with ultra-low supply/return temperatures of 45/25 °C as a novel solution for low heat-density areas in Denmark and compared the proposed ...concept with a typical tree network and with individual heat pumps to each end-users rather than district networks. It is a pump-driven system, where the separate circulation of supply and return flow increased the flexibility of the system to integrate and displace heating and cooling energy along the network. Despite the increased use of central and local water pumps to operate and control the system, the simulated overall pump energy consumption was 0.9% of the total energy consumption. This was also an advantage at the design stage as the larger pressure gradient, up to 570 Pa/m, allowed minimal pipe diameters. In addition, the authors proposed the installation of electrically heated vacuum-insulated micro tanks of 10 L on the primary side of each building substation as a supplementary heating solution to meet the comfort and hygiene requirements for domestic hot water (DHW). This, combined with supply water circulation in the loop network, served as a technical solution to remove the need for bypass valves during summer periods with no load in the network. The proposed double loop system reduced distribution heat losses from 19% to 12% of the total energy consumption and decreased average return temperatures from 33 °C to 23 °C compared to the tree network. While excess heat recovery can be limited due to hydraulic issues in tree networks, the study investigated the double loop concept for scenarios with heat source temperatures of 30 °C and 45 °C. The double loop network was cost-competitive when considering the required capital and operating costs. Furthermore, district networks outperformed individual heat pump solutions for low-heat density areas when waste heat was available locally. Finally, although few in Denmark envisage residential cooling as a priority, this study investigated the potential of embedding heating and cooling in the same infrastructure. It found that the return line could deliver cold water to the end-users and that the maximum cooling power was 1.4 kW to each end-user, which corresponded to 47% of the total peak heat demand used to dimension the double loop network.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
This review essay examines the Museum of Modern and Contemporary Art, Korea’s (MMCA) 2017–2018 exhibition on the “New Woman” (Sin yŏsŏng) and its contradictory celebration and critique of the ...multifaceted modern woman whose consumerist as well as anti-patriarchal qualities allow for mixed and often contradictory interpretations and political trajectories. Through close readings of paintings, video installations, and other works on display pertaining to the topics of objectification, commodity fetishism, and the division of labor, this essay parses the various representations of Korea’s new woman as well as her legacy in the present. The reviewer suggests that the tension between the different characteristics of the modern woman speaks to a wider ambivalence in the collective historical memory of the Japanese colonial period (1910–1945) in contemporary South Korea, which simultaneously embraces two contradictory positions: repudiation of the Japanese colonial project on the one hand and recuperation of the capitalist development initiated by colonization on the other. KCI Citation Count: 0
Citizen science approaches provide adaptable methodologies for enhancing the natural history knowledge of understudied taxa and engaging underserved populations with biodiversity. However, ...transitions to remote, virtual training, and participant recruitment in response to public health crises like the SARS‐CoV‐2 pandemic have the potential to disrupt citizen science projects. We present a comparison of outputs from a citizen science initiative built around call surveys for the Mountain Chorus Frog (Pseudacris brachyphona), an understudied anuran, in Appalachian Virginia, USA, prior to and during the SARS‐CoV‐2 pandemic. A transition to virtual training in this initiative did not lead to a decrease in scientific output and led to unexpected natural history insight about our focal taxon; however, a reliance on virtual instruction did decrease overall participation by local residents, particularly for rural K‐12 students. We discuss the trade‐offs exhibited by the adaptation of our initiative to a virtual format and provide recommendations for other citizen science initiatives facing similar restrictions in the face of current and future public health crises.
Citizen science approaches provide adaptable methodologies for enhancing the natural history knowledge of understudied taxa and engaging underserved populations with biodiversity. However, transitions to remote, virtual training, and participant recruitment in response to public health crises like the SARS‐CoV‐2 pandemic have the potential to disrupt citizen science projects. We present a comparison of outputs from a citizen science initiative built around call surveys for the Mountain Chorus Frog (Pseudacris brachyphona), an understudied anuran, in Appalachian Virginia, USA, prior to and during the SARS‐CoV‐2 pandemic.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
This article frames the Museum of Modern Art, Hayama’s 2017 exhibition on Japanese modernism during the simultaneously vibrant and tumultuous 1930s through the lens of Japan’s uneven capitalist ...development and wartime mobilization. The author suggests that the exhibition’s unique international scope, rich selection of figurative and abstract modernist works, and emphasis on the year 1937 as a nexus through which the decade’s competing tendencies can be reevaluated readily disclose the constitutive, dialectical relationships between historical difference, total war, and modernist form in imperial Japan and its colonies. The exhibition’s featured works and curator Asaki Yuka’s direction together emphasized the inseparability of Japanese modernism from the encroaching conditions of world war during the late 1930s, thereby contributing to a growing body of scholarship and series of exhibitions challenging the received oppositions between autonomous modernism, proletarian realism, and wartime propaganda. After introductory remarks on the reassessment of 1930s-era Japanese avant-garde aesthetics, the article provides a series of close readings of significant paintings included in the exhibition, including Murai Masanari’s 1937 Urban, Matsumoto Shunsuke’s 1935 Building, and Uchida Iwao’s 1937 Port. These formal readings explore how the year 1937 marked a pivotal “branch point” for Japanese society, not only in terms of the confluence of various artistic trends but also in terms of the fierce opposition between socialism and fascism that bifurcated potentialities for Japan’s future. KCI Citation Count: 0
With increasing focus on the performance of district heating systems, a concept is developed to obtain low district heating return temperatures from domestic hot water systems with a high share of ...circulation loss. For these systems, it is challenging to realize a low district heating return temperature by direct heat exchange only, due to the high flow of circulation return water at 50 °C. The concept is termed Circulation Booster. The purpose of the Circulation Booster is to boost the domestic hot water circulation temperature and at the same time secure a low district heating return temperature from this part of the service. The domestic hot water circulation temperature is heated in two steps: direct heat exchange and a heat pump. The heat source for the Circulation Booster is district heating, and the heat pump itself is driven by electricity. The paper includes the field experiences from a 1-year test period, concluding that the concept is operating as intended. Further, the performance results regarding electric consumption and district heating return temperatures and an economic feasibility study are presented. The current tariff structure in Denmark related to the district heating return temperature and electric costs gives a feasible economic case for the Circulation Booster concept with a direct payback time of 5,1 years. An increasingly progressive tariff scheme for low district heating return temperature or lower electric costs could further improve the economic feasibility of the Circulation Booster concept.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Airtight energy-efficient buildings of today need efficient ventilation to secure high indoor air quality. There is a need for affordable and reliable sensors to make demand control available in a ...broad range of ventilation systems. Low-cost metal oxide semiconductor (MOS) volatile organic compound (VOC) sensors offer such a possibility, but they are usually non-selective and react to broad range of compounds. The objective of the present paper was to use cluster analysis to assess the ability of five commercially available MOS VOC sensors to detect pollutants in a residential setting. We studied three scenarios: emissions from people (human bioeffluents), furnishing materials (linoleum), and human activity (surface cleaning with spray detergent). We monitored each scenario with five MOS VOC sensors and a proton-transfer-reaction–time-of-flight mass spectrometer (PTR-ToF-MS). We applied an agglomerative hierarchical clustering algorithm to evaluate the dissimilarity between clusters. Four of the five tested sensors produced signals in agreement with the concentration patterns measured with the PTR-ToF-MS; one sensor underperformed in all cases. Three sensors showed a very similar performance under all emission scenarios. The results showed that the clustering could help in understanding whether a particular sensor matched the intended emission scenario.
In current building design practices, the operation and performance of heating, ventilation and air conditioning (HVAC) systems are rarely documented in detail. This is mainly caused by the manual ...burden of generating detailed HVAC simulation models. To lower the barrier for detailed HVAC simulations, this paper presents an automated toolchain that generates and simulates models in Modelica language utilizing building information structured in a web-based common data environment. This approach differs from previous approaches by its focus on HVAC systems and integration with a common data environment over file-based BIM, which increases interoperability and allows users to run simulation studies in the cloud. The tool successfully generated and simulated a model of the HVAC systems in a small building under ideal and faulty operation of the heating system and thus demonstrated a fully interoperable data exchange between a common data environment and a simulation environment while showcasing the potential of analyzing HVAC systems with Modelica.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
•The simulated rotary heat exchanger provided moisture concerns in several rooms.•The rotary heat exchanger was only suitable for ventilation of so-called dry rooms.•Varying heat recovery or ...temperature can limit indoor relative humidity in dry rooms.•Single-room ventilation allows selection of heat recovery to match the needs of rooms.
The investigation constructed and simulated moisture balance equations for single-room ventilation with a non-hygroscopic rotary heat exchanger. Based on literature, the study assumed that all condensed moisture in the exhaust subsequently evaporated into the supply. Simulations evaluated the potential for moisture issues and compared results with recuperative heat recovery and whole-dwelling ventilation systems. To assess the sensitivity of results, the simulations used three moisture production schedules to represent possible conditions based on literature. The study also analyzed the sensitivity to influential parameters, such as infiltration rate, heat recovery, and indoor temperature. With a typical moisture production schedule, the rotary heat exchanger recovered excessive moisture from kitchens and bathrooms, which provided a mold risk. The rotary heat exchanger was only suitable for single-room ventilation of dry rooms, such as living rooms and bedrooms. The sensitivity analysis concluded that varying heat recovery or indoor temperature could limit indoor relative humidity in dry rooms when a moderate risk was present. The rotary heat exchanger also elevated the minimum relative humidity in each room, which could help to avoid negative health impacts. A discussion emphasized the potential benefits of selecting heat recovery to match the individual needs of each room.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Diabetes is a threat to peoples’ lives around the world, particularly in the Middle East. Medicine misuse and poor glycaemic control are prevalent among patients with type 2 diabetes, especially ...insulin-dependent patients (Alsairafi et al., 2016). With advances in medical technology, insulin pumps became a treatment option for patients with type 1 diabetes and those with insulin-dependent type 2 diabetes. However, use of these devices is still lacking in Kuwait, particularly in patients with type 2 diabetes. Information on how patients manage these devices and their efficacy and safety from the perspectives of patients is also lacking (Alsaleh et al., 2016).
To examine the views and experiences of adults with type 2 diabetes regarding the use of insulin pumps compared to their previous insulin delivery methods, in terms of glycaemic control, quality of life, preference, convenience and adherence to doses.
The main five secondary-care hospitals in Kuwait: Mobarak Al-Kabeer, Al Amiri, Al Adan, Al Farwaniya and Al Jahra.
All adults with type 2 diabetes who used an insulin pump were invited to participate. Data were collected through semi-structured interviews. Data analysis was performed using MAXQDA-11.
A total of eight patients were interviewed. Interviews with patients revealed that using an insulin pump improved patients’ glycaemic control and quality of life as a consequence of improved satisfaction and adherence to doses.
From the perspective of adults with type 2 diabetes, there are lots of benefits of using insulin pumps over other insulin delivery methods, mainly seen by the improvement of quality of life and patients’ adherence to doses. Policy-makers and healthcare professionals (HCPs) must be aware of such benefits and should support the wider implementation of this technology in the country by including patients with type 2 diabetes. Results of this study will help to inform healthcare provision and guideline modifications and to provide guidance for new patients using this therapy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP