bluuebunny/crossref_metadata_2025 huggingface dataset:
Epidemiological and Molecular Investigation of Multidrug-Resistant Enterococcus spp. Strains Isolated from Hospitalized Patients Using a One-Health Approach
Authors: Schell Celia María , Blancato Víctor Sebastián , Carbone Ruth Jésica , Mauro María Josefina , Torres Vanina , Magni Christian
Published: March 2024

Aims: The surveillance and investigation of antimicrobial resistance and virulence factor genes in nosocomial pathogens such as Enterococcus spp. have not been adequately prioritized within health institutions, especially in the context of COVID-19. The objective of this work was to conduct an epidemiological and molecular study in multidrug-resistant Enterococcus spp. strains isolated from hospitalized patients using a "One Health" approach in the middle of the COVID-19 pandemic.

Study Design: An observational, prospective, cross-sectional study was designed. All strains were isolated from hospitalized patients in a public hospital in La Plata, Buenos Aires, Argentina from September 2019 to August 2021; coincidental with the COVID-19 pandemic.

Methodology: In this study, we used N=17 Enterococcus spp. detected by biochemical testing and BD Phoenix™ M50: E. faecalis (n=6) and E. faecium (n=11). Antimicrobial susceptibility was determined according to standard guidelines (disk diffusion and MIC). AR and VF genes were detected by PCR assays.

Results: 10/11 (90.9%) vancomycin-resistant E. faecium strains were confirmed by molecular test. The highest detection of vanA-VREFM resulted after the pandemic cohort (2021). Resistance to glycopeptides was associated with resistance to ß-lactams and high-level resistance to aminoglycosides. The gen aac(6′)-Ie-aph(2″)-Ia was detected in E. faecium (n=7) and E. faecalis (n=1). The esp gene (52.9%) was the most frequent virulence factor, followed by gelE 7 (41.2%) and cylA 1 (5.9%) among E. faecalis and E. faecium isolates.

Conclusions: Nosocomial pathogens and commensal bacteria such as Enterococcus have an essential role in spreading AR and VF using genome plasticity to transfer genes located in MGE. The epidemiological and molecular investigation of multidrug-resistant strains allows adjusting biosafety protocols to prevent their spread.
Climate Change Impact Assessment and Disaster Risk Financing Strategies in Mali: A Comprehensive Analysis of Drought and Flood Events
Authors: Neya Tiga , Yanon Galine , Soubeiga Jonas , Kiribou Razak , Neya Oble , Magistro John
Published: March 2024

Climate change impact increasingly led to humanitarian assistance increase and needed. To better address climate change impacts mitigation, a suitable financing instrument is essential to facilitate government, humanitarian, and other stakeholders' finance mobilization. However, few studies have been done on disaster risk profiling to guide decision-makers in their choices.  Disaster risk profile analysis has been conducted in Mali to facilitate financial resources mobilization and climate finance instrument choice by identifying Historical drought and flood events. To do so, published papers; and some international institution websites dealing with climate hazard events such as Reliefweb, Hazard/risk, climate information services, Relief Web; CRED- EM-DAT; World Bank Climate Knowledge Portal, World Bank- UNDRR -ThinkHazard, WFP ARC/GeoNode/VAM/DataViz addressing Mali country have been assimilated for evidence accumulation and synthesis and presented in a database. Furthermore, national statistics and national reports on hazards have been also reviewed. Before starting the reading exercise, a reading/analytical framework has been elaborated.  In Mali the year 1984 to 2019, 21 flood events occurred in Mali and the most exposed regions to floods are Koulikoro, Bamako and Gao. From 1969 to 2020, 21 drought events were registered in in Mali and the most affected regions are Koulikoro, Mopti, Gao, Kayes.  The time return period of drought has been estimated to 3 years while the time return of flood has been estimated to be about 2 years. Drought events are less frequent than flood events, however, drought events affect more population than floods.  Also, Also, the yearly response cost for drought events is USD million 277.46   with an average US USD 204.37 cost per affected population.  For the flood, even the yearly response cost is USD 11.107 million With USD 261.82 per affected population.  Macro-insurance and CAT bonds are more suitable disaster risk financing instruments and are recommended to better address drought events while Anticipatory action and government contingency funds are more suitable climate disaster risk financing instruments to better address flood events in Mali.
Rainfall Variability and Rice Production: An Assessment Based on the Variability in Indian Monsoon and Ground Water Level of Punjab, India
Authors: Chand Shivani , Dhaliwal L. K.
Published: March 2024

In Punjab, 99 per cent of total cultivated area is under irrigation but it is at the cost of declining ground water table. Due to rainfall variability and very high requirement of water in rice crop, which occupy large area in the state during kharif season, has further deteriorated the situation of water resources. Therefore, this study was conducted to identify the relationship between declining groundwater level, variable monsoonal rainfall and rice yield of different agroclimatic zones of Punjab. The historical data of rainfall for different locations of Punjab viz. Amritsar (1998-2017), Ballowal Saunkhri (1998-2017), Bathinda (1998-2017), Ludhiana (1998-2017) and Patiala (1998-2017) was collected from the Department of Climate Change and Agricultural Meteorology, PAU, Ludhiana and Met Centre, IMD Chandigarh. The productivity data of rice was collected from indiastat.com and Statistical Abstract of Punjab whereas the data related to groundwater table (1998-2017) were collected from the Central Ground Water Board, Punjab. It was observed that the ground water table level showed significant decrease after 2005 at all locations and there was a positive correlation between rice yield and ground water table at all the locations except at Amritsar where it was negatively correlated. The deficit rainfall years showed very less impact on rice yield which has increased continuously. However, the relationship between groundwater table and rainfall indicated that deficit monsoonal rainfall led to further decline in groundwater table as it was not recharged.
Fears and Challenges of Acting in the Pandemic Time
Authors: Basuki Ribut
Published: March 2024

E-learning has become a popular approach today. However, in drama/theater classes where exercises, rehearsals, and ‘productions’ are done on stage, such an approach was considered impossible, until Covid-19 pandemic strike occurred. The purpose of this paper is to reveal how acting classes dealt with the disruption, the process of selecting and implementing online meeting platforms, the new ‘lesson plan’ to finish the classes, the challenges due to the changes, and evaluation for future practices. The nature of the study is both explanatory and evaluative by action research. Primary data were collected using personal observations and questionnaires. Secondary data were taken from library research pertaining drama/theater, e-learning, online teaching, action research, thematic analysis, etc. By flipping from offline to online learning, acting classes turned out to be manageable. Radical and innovative adaptations should be made to make classes work online, including flipping offline to online meetings, implementing screen/camera knowledge, and using online platforms such as Google Meet, Zoom, WA, and LINE. Moreover, despite the fact that initially online meeting was threatening to the students and the teacher alike, using online meeting platforms for acting classes as blended learning was a good challenge, given appropriate situations and purposes.
Describing Translation Techniques Used in the Translation of Culturally Bound Terms in West Java Calendar of Event 2020
Authors: Purwaningsih Dyah Raina , Yulianita Nadia Gitya
Published: March 2024

This research aims at analyzing translation techniques used by the translator in translating the booklet "West Java Calendar of Event 2020" from Indonesian into English. This booklet is published by the Department of Tourism and Culture, West Java. Specifically, this research highlights the translation of culturally bound terms in the booklet. The researchers are interested in analyzing this topic because cultural-bound terms are considered challenging to translate; the translators must understand the cultural background of the languages they are translating. Moreover, it is not likely that translators can find one-to-one correspondence for each cultural term in the text. This study applies a descriptive qualitative method since the data are in the form of text and the researchers also play a role as the key instrument in collecting the data, in this case through document examination. In this research, total sampling technique is applied since the researchers take all of the culturally bound terms in the booklet. The research begins with collecting the cultural terms from the booklet, classifying them into cultural terms categories based on Newmark’s theory of cultural category, and determining the translation techniques based on Molina and Albir’s theory. The result shows that the translator mainly employs borrowing, amplification, description, and established equivalent techniques. There is a tendency that the translator prefers those techniques because it is hard for the translator to find one-to-one correspondence of the terms in the target language. Hopefully, this research will be beneficial for translators in deciding the proper translation techniques in translating cultural terms.
Spectocurrency: War Spectacle in Social Media
Authors: Syamsi Vera
Published: March 2024

Social media has been influential and important in people’s life as a place for socializing, finding entertainment and - nowadays- information. People share various images and videos – or spectacles- through the platforms, with Tik Tok and Instagram as two of the most popular platforms. This research highlights and analyzed war spectacles created by the President of Ukraine and a Ukrainian university student on those platforms that were aimed at raising people’s awareness and empathy to the sufferings of the country and hopefully support their fight against Russia’s invasion, using semiotics concept, and proves that spectacles do have power to move people and generate reaction that can eventually cause expected changes, or spectocurrency.
‘Not Too Hot, Not Too Cold, Just Right’: Empathetic Communication of Indonesian Big Brands through YouTube during the COVID-19 Pandemic
Authors: Luik Jandy E. , Aritonang Agusly Irawan
Published: March 2024

This article is based on an exploratory study of YouTube videos related to the COVID-19 pandemic released by the official accounts of several big brands in Indonesia. By analyzing the videos released by these companies, a combination of key messages that are professionally conveyed to present the actions taken by the brands, in response to the pandemic, with an empathetic feel was found. While there is ample evidence to map out the creative processes behind these videos, our findings show that the brands aim to cover up the techniques they employ in achieving their goals, such as the sending of excessively sympathetic messages. The findings of this study provide initial empirical evidence of Indonesian companies’ tendency to assimilate the local culture of mutual assistance and the existence of branding activities that continue to be carried out during the pandemic. This article ends with a discussion of the communication processes carried out by commercial entities in challenging times.
Board Game Prototype About the Historical Period of Japanese Colonialism in Indonesia for Middle School Students
Authors: Soebakti Jonathan Winfredo Wongso , Tanudjaja Bing Bedjo , Salamoon Daniel Kurniawan
Published: March 2024

The teaching method used in history subjects usually needs a lot of memorizations, considered less interesting and less important compared to other subjects leading to difficulties to memorize the topic. The other reason the students think that history is not too important is because they are more interested in other countries' cultures. This prototype is made mainly for middle school students so that they are motivated and more interested to learn Indonesian history. This prototype uses qualitative research and uses 5W+1H data analysis. With the creation of the Koloni board game, we hope that the students can be more interested in learning and understanding Indonesian history.
Bullish Sentiment on Price Upward Trend: A Netnographic Study of Cryptocurrency Communities
Authors: Tjahyana Lady Joanne
Published: March 2024

Cryptocurrency as a digital decentralized currency has attracted many investors and obtained a lot of support from communities. Previous studies have concluded that there were indeed connections between community sentiment and cryptocurrency price movement. However, most of the research was conducted using sophisticated methods that are difficult to utilize by cryptocurrency investors. This research objective was to find practical ways to identify bullish sentiment during price upward trend especially during the Covid-19 omicron variant outbreak that started in the last quarter of 2021. Netnography method was used as a qualitative approach for this research to get insight from cryptocurrency communities. LunarCrush web application as a more user-friendly tool, was being used to analyze bullish sentiment and price data. During December 2021 until January 2022, 303 price upward trend data from 264 coins had been collected and analyzed. The result of this research revealed 5 categories of bullish sentiment messages from top influencers which are community booster, official information, project updates, achievement, and trading plan. However, it can be concluded that price movements were not always related to bullish sentiment. Thus, bullish sentiment should not be used as the sole factor to identify price upward trends. Furthermore, investors should join the cryptocurrency community to understand the characteristics of bullish sentiment and not just rely on data from monitoring tools. Interestingly, there were no Covid-19 related topics on bullish sentiment collected. Hence, it did not necessarily need to publish good news related to Covid-19 handling to create bullish sentiment among the investors.
Improving Net Energy Efficiency of Dimethyl Ether Production Process by Methanol Dehydration
Authors: Permatasari Astrid Eka , Syabila Syalaisa Nanda , Dewi Hly Tyas Ajeng Kartika , Zahra Rufaidah Nilam
Published: March 2024

Dimethyl ether (DME) is a source of fuel that produces clean energy for the future. Methanol can be used as a raw material for the manufacture of DME as a natural gas that is treated for synthesis. This paper evaluates how to improve net energy efficiency in DME production and how to review the net energy efficiency calculations in DME production. Methods used for production of DME are methanol dehydration, thermodynamics examination, also improving the net energy efficiency of DME with the addition of the heat exchanger (E-100), the addition of a heater (E-104) before entering a column (T-102), and moved the mixer position before the heater (E-100). By modifying the addition of a heat exchanger (E-100), heater (E-104), and changing the position of the mixer in DME production, it has been proven that it can reduce energy requirements in the dimethyl ether synthesis process from methanol and increase net energy efficiency by up to 98.83%. The results of the case study indicate that the addition heat exchanger (E-100) able to reduce the heater load after the creation process and remove the cooler (E-101) that existed before creation, then the addition of the heater (E-104) serves to reduce the load of Qcond2 and Qreb2 on columns (T-102), also the position of the mixer for the methanol recycling flow is moved before the heater (E-100) is intended to remove the heaters (E-103). Copyright © 2024 by Authors, Published by Universitas Diponegoro and BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).
Optimization of Energy Consumption in Formaldehyde Production Process Using Reboiled Absorption Process
Authors: Sebastian Calvinio Juan , Adhyaksa Fidelis Neo , Kamal Mutiara Tabitha , Susanto Vincentius Edward
Published: March 2024

Formaldehyde is a crucial chemical building block in various industries, and its production often involves energy-intensive processes. This study focuses on optimizing energy consumption in formaldehyde production, explicitly employing the reboiled absorption process with a production capacity of 27,000 tons per year. The objective of this article is to develop a more energy-efficient process of formaldehyde synthesis by addition or refrigerant cycle stream to preserve the energy, reducing energy consumption and improving the sustainability of the process. The reboiled absorption process involves the absorption of formaldehyde gas into a liquid absorbent, followed by reboiling to release the absorbed formaldehyde. A comprehensive analysis of the entire production system compares unmodified and modified process simulations, heat integration, and energy analysis. Beside the energy consumption of the process, the number of stages within the absorption process contributes to the product mass flow rate of the overall process by increasing the surface area which mass transfer can occur. However, adding too many stages to the process may negatively impact the energy efficiency of the process. Therefore, optimizing energy consumption and absorption processes in formaldehyde production is essential to improve the sustainability of the process and increase the overall profitability of the production process. The results show that the proposed method dramatically improves the sustainability of CH2O synthesis by reducing overall energy consumption and emissions by 93.978%, reducing energy consumption from 153,735,360.4 kJ/h to 9,256,646.618 kJ/h. Copyright © 2024 by Authors, Published by Universitas Diponegoro and BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).
Enhancing Energy Efficiency of Cumene Production Through Reactor Output Recycling Modification in a Heat Exchanger
Authors: Sutjahjo Finishia , Medri Lathifa , Alyani Syarafina , Budhy Cindy Leviona
Published: March 2024

Cumene production generally involves irreversible and exothermic reactions that leads to an increase in product temperature and needs to be cooled for further processes. The high temperature of reactor product can be utilized as a heat transfer fluid in heat exchanger. This modification process is essential for improving energy efficiency by recycling the reactor output with high temperature as a heat transfer fluid, so that the implementation of replacing the heater with a heat exchanger can be carried out for the process of increasing the initial feed temperature. In an effort to enhance energy efficiency in the cumene production process, simulations were conducted using HYSYS and the comparison of energy efficiency for both basic and modified processes can be evidenced by comparing the total amount of energy required during the process. The results shows that the total amount of energy required for the modified process is 39,814,003.7 kJ/h, while for the basic process is 40,588,937.4 kJ/h, with a difference of 774,933.7299 kJ/h. Since the total amount of energy required in the modified process is smaller than the basic process, then the modification process will increase the energy efficiency of cumene production. Copyright © 2024 by Authors, Published by Universitas Diponegoro and BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).
Developmental regulation of α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazole‐propionic acid receptor subunit expression in forebrain and relationship to regional susceptibility to hypoxic/ischemic injury. I. Rodent cerebral white matter and cortex
Authors: Talos Delia M. , Fishman Rachel E. , Park Hyunkyung , Folkerth Rebecca D. , Follett Pamela L. , Volpe Joseph J. , Jensen Frances E.
Published: May 2006

This is the first part of a two‐part study to investigate the cellular distribution and temporal regulation of α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazole‐propionic acid receptor (AMPAR) subunits in the developing white matter and cortex in rat (part I) and human (part II). Western blot and immunocytochemistry were used to evaluate the differential expression of AMPAR subunits on glial and neuronal subtypes during the first 3 postnatal weeks in the Long Evans and Sprague Dawley rat strains. In Long Evans rats during the first postnatal week, GluR2‐lacking AMPARs were expressed predominantly on white matter cells, including radial glia, premyelinating oligodendrocytes, and subplate neurons, whereas, during the second postnatal week, these AMPARs were highly expressed on cortical neurons, coincident with decreased expression on white matter cells. Immunocytochemical analysis revealed that cell‐specific developmental changes in AMPAR expression occurred 2–3 days earlier by chronological age in Sprague Dawley rats compared with Long Evans rats, despite overall similar temporal sequencing. In both white and gray matter, the periods of high GluR2 deficiency correspond to those of regional susceptibility to hypoxic/ischemic injury in each of the two rat strains, supporting prior studies suggesting a critical role for Ca2+‐permeable AMPARs in excitotoxic cellular injury and epileptogenesis. The developmental regulation of these receptor subunits strongly suggests that Ca2+ influx through GluR2‐lacking AMPARs may play an important role in neuronal and glial development and injury in the immature brain. Moreover, as demonstrated in part II, there are striking similarities between rat and human in the regional and temporal maturational regulation of neuronal and glial AMPAR expression. J. Comp. Neurol. 497:42–60, 2006. © 2006 Wiley‐Liss, Inc.
Country of birth and hospital admission rates for mental disorders: a cohort study of 4.5 million men and women in Sweden
Authors: Westman J. , Johansson L.M. , Sundquist K.
Published: May 2006

This study analysed the association between country of birth and psychotic, affective, and neurotic disorders in seven immigrant categories, after adjustment for demographic and socioeconomic factors. A 2-year national cohort study of 4.5 million individuals in the age group 25–64 years was performed. Swedish national registers including individual demographic and socioeconomic data were linked to the hospital discharge register. Cox regression was used in the analysis. Several groups of immigrants, both men and women, had risks of hospital admission for psychotic, affective, or neurotic disorders compared to the Swedish-born reference group. The impact of demographic and socioeconomic factors on these risks seemed to be larger for men than for women. For foreign-born men, several of the risks no longer remained significant after adjustment for income and marital status. In contrast, most of the risks for foreign-born women remained significant after adjustment for income and marital status. Low income and being single were associated with an increased risk of psychiatric hospital admission. These results represent important knowledge for clinicians and public health planners who are involved in treatment and prevention of mental disorders among certain groups of immigrants, and among low income men and women irrespective of immigrant status.
Assessing aggressiveness quickly and efficiently: the Spanish adaptation of Aggression Questionnaire-Refined version
Authors: Gallardo-Pujol David , Kramp Uwe , García-Forero Carlos , Pérez-Ramírez Meritxell , Andrés-Pueyo Antonio
Published: May 2006

The assessment of aggressiveness and the prediction of aggression has become a relevant research and applied topic in Psychiatry and Psychology. There have been many attempts in order to get a fast and reliable tool to measure aggression. Buss and Durkee started the pathway, and recently Bryant and Smith developed a tool with an enormous potential, a fast-applicable, reliable and valid test. We herein report a Spanish adaptation of this test and we show that aggressiveness can be measured rapidly, and in a simple, valid and reliable way across different populations. We focus on the discriminant capacity of this test to detect aggressive individuals.
Caspase‐8 acts as a key upstream executor of mitochondria during justicidin A‐induced apoptosis in human hepatoma cells
Authors: Su Chun-Li , Huang Lynn L.H. , Huang Li-Min , Lee Jenq-Chang , Lin Chun-Nan , Won Shen-Jeu
Published: May 2006

Justicia procumbens is a traditional Taiwanese herbal remedy used to treat fever, pain, and cancer. Justicidin A, isolated from Justicia procumbens, has been reported to suppress in vitro growth of several tumor cell lines as well as hepatoma cells. In this study, justicidin A activated caspase‐8 to increase tBid, disrupted mitochondrial membrane potential (Δψ
m), and caused the release of cytochrome c and Smac/DIABLO in Hep 3B and Hep G2 cells. Justicidin A also reduced Bcl‐xL and increased Bax and Bak in mitochondria. Caspase‐8 inhibitor (Z‐IETD) attenuated the justicidin A‐induced disruption of Δψ
m. Growth of Hep 3B implanted in NOD‐SCID mice was suppressed significantly by oral justicidin A (20 mg/kg/day). These results indicate that justicidin A‐induced apoptosis in these cells proceeds via caspase‐8 and is followed by mitochondrial disruption. Supplementary materials are available at http://myweb.ncku.edu.tw/~a725/.
Millennial‐scale temperature variations in North America during the Holocene
Authors: Viau A. E. , Gajewski K. , Sawada M. C. , Fines P.
Published: May 2006

A mean continental July temperature reconstruction based on pollen records from across North America quantifies temperature variations of several timescales for the past 14,000 cal yr BP. In North America, temperatures increased nearly 4°C during the late glacial, reaching maximum values between 6000 and 3000 cal yr BP, after which mean July temperatures decreased. Superimposed on this orbital‐scale trend are millennial‐scale temperature variations that appear coherent in structure and frequency with high‐resolution ice, marine and other terrestrial paleoclimate records of the Holocene. During the Holocene, climate in North America appears to have varied periodically every ∼1100 years rather than the ∼1500 year cycle found during the last glacial period. Coherence at frequencies between 900 and 1100 years between land, ice, and ocean records suggests a common forcing associated with widespread surface impacts during the Holocene. These results provide important insight to the global warming debate, as the observed twentieth century temperature increase appears unprecedented compared to our mean North American temperature reconstruction of the past 14,000 years.
Time‐dependent inversion estimates of global biomass‐burning CO emissions using Measurement of Pollution in the Troposphere (MOPITT) measurements
Authors: Arellano Avelino F. , Kasibhatla Prasad S. , Giglio Louis , van der Werf Guido R. , Randerson James T. , Collatz G. James
Published: May 2006

We present an inverse‐modeling analysis of CO emissions using column CO retrievals from the Measurement of Pollution in the Troposphere (MOPITT) instrument and a global chemical transport model (GEOS‐CHEM). We first focus on the information content of MOPITT CO column retrievals in terms of constraining CO emissions associated with biomass burning and fossil fuel/biofuel use. Our analysis shows that seasonal variation of biomass‐burning CO emissions in Africa, South America, and Southeast Asia can be characterized using monthly mean MOPITT CO columns. For the fossil fuel/biofuel source category the derived monthly mean emission estimates are noisy even when the error statistics are accurately known, precluding a characterization of seasonal variations of regional CO emissions for this source category. The derived estimate of CO emissions from biomass burning in southern Africa during the June–July 2000 period is significantly higher than the prior estimate (prior, 34 Tg; posterior, 13 Tg). We also estimate that emissions are higher relative to the prior estimate in northern Africa during December 2000 to January 2001 and lower relative to the prior estimate in Central America and Oceania/Indonesia during April–May and September–October 2000, respectively. While these adjustments provide better agreement of the model with MOPITT CO column fields and with independent measurements of surface CO from National Oceanic and Atmospheric Administration Climate Monitoring and Diagnostics Laboratory at background sites in the Northern Hemisphere, some systematic differences between modeled and measured CO fields persist, including model overestimation of background surface CO in the Southern Hemisphere. Characterizing and accounting for underlying biases in the measurement model system are needed to improve the robustness of the top‐down estimates.
Subsurface temperatures during the last millennium: Model and observation
Authors: Beltrami Hugo , González‐Rouco J. F. , Stevens M. B.
Published: May 2006

General Circulation Models (GCMs) used to distinguish anthropogenic forcing of the Earth's past climate from its natural variability need to be validated by observations. The GCM ECHO‐g was used to produce three millennial simulations of the Earth's climate. Two simulations include changes in anthropogenic and natural external forcing factors through the last millennium, differing only in their initial conditions, and a control run with constant external forcing representing internal variability. Since the ground contains a record of long‐term trends in SAT, we use borehole temperatures in Canada, grouped into regions, as a record of past climate. The regional average SATs from ECHO‐g were used to solve the forward subsurface thermal profile, and compared with the underground temperature anomalies observed at each region. In all cases simulated subsurface anomalies from the forced simulations are in better agreement with observations than those from the control simulation.
Analytical study of excitation and measurement of fluid‐solid interface waves
Authors: Zhu Jinying , Popovics John S.
Published: May 2006

Analytical analyses are performed to investigate the pressure and particle velocity responses in fluid/solid half spaces subject to impulsive sources. This study has significance for underwater seabed characterization efforts that use interface waves. Results show that pressure (e.g., measured by hydrophones) in the fluid is more sensitive for interface wave sensing than particle velocity (e.g., measured by geophones) at the fluid‐solid interface. Both types of impulsive point wave sources, explosive action in fluid and mechanical action on solid, are investigated with regard to the excitability of interface waves. Analyses show that a mechanical load applied normal to the interface generates higher amplitude interface waves, relative to the acoustic wave amplitude, than an explosive load in the fluid. The effect of explosive source height is also investigated. Results show that Scholte wave amplitude is affected by the explosive source height, and decays quickly with increasing height. However, explosive source height has little effect on generated leaky Rayeligh wave amplitude.
Equations of state in a lattice Boltzmann model
Authors: Yuan Peng , Schaefer Laura
Published: May 2006

In this paper we consider the incorporation of various equations of state into the single-component multiphase lattice Boltzmann model. Several cubic equations of state, including the van der Waals, Redlich-Kwong, and Peng-Robinson, as well as a noncubic equation of state (Carnahan-Starling), are incorporated into the lattice Boltzmann model. The details of phase separation in these nonideal single-component systems are presented by comparing the numerical simulation results in terms of density ratios, spurious currents, and temperature ranges. A comparison with a real fluid system, i.e., the properties of saturated water and steam, is also presented.
Aeolian tones radiated from flow past two square cylinders in tandem
Authors: Inoue O. , Mori M. , Hatakeyama N.
Published: May 2006

The sound generated by two square cylinders placed in a tandem arrangement in a uniform flow at low Mach numbers is studied by direct solution of the two-dimensional unsteady compressible Navier-Stokes equations. Special attention is paid to the effect of the spacing between the two cylinders on the generation mechanism of the sound. Results show that the magnitude of the generated sound varies drastically depending on the spacing. When the spacing is small, roll-up of the shear layer separated from the upstream cylinder is suppressed and the sound generation is also suppressed; near a critical value of the spacing, the magnitude of the generated sound is about 10−2 as small as that generated by a single square cylinder. With increased spacing beyond a critical value, the shear layer separated from the upstream cylinder rolls up to form vortices in front of the downstream cylinder; the rolled-up vortices interact with the downstream cylinder, leading to a drastic increase in the magnitude of the generated sound. The results also suggest that the generated aeolian tone may show hysteresis.
Lagrangian analysis of fluid transport in empirical vortex ring flows
Authors: Shadden Shawn C. , Dabiri John O. , Marsden Jerrold E.
Published: May 2006

In this paper we apply dynamical systems analyses and computational tools to fluid transport in empirically measured vortex ring flows. Measurements of quasisteadily propagating vortex rings generated by a mechanical piston-cylinder apparatus reveal lobe dynamics during entrainment and detrainment that are consistent with previous theoretical and numerical studies. In addition, the vortex ring wake of a free-swimming Aurelia aurita jellyfish is measured and analyzed in the framework of dynamical systems to elucidate similar lobe dynamics in a naturally occurring biological flow. For the mechanically generated rings, a comparison of the net entrainment rate based on the present methods with a previous Eulerian analysis shows good correspondence. However, the current Lagrangian framework is more effective than previous analyses in capturing the transport geometry, especially when the flow becomes more unsteady, as in the case of the free-swimming jellyfish. Extensions of these results to more complex flow geometries is suggested.
Mechanism of drag reduction by dimples on a sphere
Authors: Choi Jin , Jeon Woo-Pyung , Choi Haecheon
Published: May 2006

In this Letter we present a detailed mechanism of drag reduction by dimples on a sphere such as golf-ball dimples by measuring the streamwise velocity above the dimpled surface. Dimples cause local flow separation and trigger the shear layer instability along the separating shear layer, resulting in the generation of large turbulence intensity. With this increased turbulence, the flow reattaches to the sphere surface with a high momentum near the wall and overcomes a strong adverse pressure gradient formed in the rear sphere surface. As a result, dimples delay the main separation and reduce drag significantly. The present study suggests that generation of a separation bubble, i.e., a closed-loop streamline consisting of separation and reattachment, on a body surface is an important flow-control strategy for drag reduction on a bluff body such as the sphere and cylinder.
Mixing of macroscopically quiescent liquid mixtures
Authors: Lamorgese Andrea G. , Mauri Roberto
Published: May 2006

We simulate the mixing process of a quiescent binary mixture that is instantaneously brought from the two to the one-phase region of its phase diagram. Our theoretical approach follows the diffuse interface model, where convection and diffusion are coupled via a body force, expressing the tendency of the demixing system to minimize its free energy. In liquid systems, as this driving force induces a material flux which is much larger than that due to pure molecular diffusion, drops tend to coalesce and form larger domains, therefore accelerating all phase separation processes. On the other hand, convection induced by phase transition effectively slows down mixing, since such larger domains, eventually, must dissolve by diffusion. Therefore, whenever all other convective fluxes can be neglected and the mixture can be considered to be macroscopically quiescent, mixing is faster for very viscous mixtures, unlike phase separation which is faster for very fluid mixtures. In addition, the mixing rate is also influenced by the Margules parameter Ψ, which describes the relative weight of enthalpic versus entropic forces. In the late stage of the process, this influence can approximately be described assuming that mixing is purely diffusive, with an effective diffusivity equal to D[1−2Ψϕ¯(1−ϕ¯)], where D is the molecular diffusivity and ϕ¯ is the mean concentration. That shows that mixing at late stages is characterized by a self-similar solution of the governing equations, which leads to a t−1 power law decay for the degree of mixing, i.e., the mean square value of the composition fluctuations.
A note on the Rayleigh-Taylor instability with phase change
Authors: Ozen O. , Narayanan R.
Published: May 2006

A commonly used approximation in the study of the effect of phase change on Rayleigh-Taylor instability is recalled and reexamined. This approximation incorporates the use of a constant phenomenological coefficient to simplify the model. However, the phenomenological coefficient depends on the wavenumber, and therefore its use as a constant input must be questioned. We employ the solution of the full model to find the variation of this coefficient with the wavenumber and show that this dependence can be strong.
Suppressing falling film instabilities by Marangoni forces
Authors: Demekhin Evgeny A. , Kalliadasis Serafim , Velarde Manuel G.
Published: May 2006

The linear stability of a thin liquid layer falling down an inclined wall heated by a downstream linearly increasing temperature distribution is investigated. It is shown that hydrodynamic and Marangoni instabilities yield two types of transverse instabilities: long surface waves and convective rolls, and longitudinal convective rolls, much like in the case of a uniformly heated wall. However, in contrast to the problem of a uniformly heated wall, where the thermocapillary forces have a destabilizing influence on all instability modes, here they can either destabilize or stabilize the flow. For liquids with sufficiently large Prandtl numbers, increasing the temperature gradient first destabilizes the flow and then stabilizes it. On the other hand, for small Prandtl numbers, increasing the temperature gradient leads to a monotonic stabilization of all instability modes.
Minichromosome maintenance helicase activity is controlled by N- and C-terminal motifs and requires the ATPase domain helix-2 insert
Authors: Jenkinson Elizabeth R. , Chong James P. J.
Published: May 2006

The minichromosome maintenance (MCM) proteins are essential conserved proteins required for DNA replication in archaea and eukaryotes. MCM proteins are believed to provide the replicative helicase activity that unwinds template DNA ahead of the replication fork. Consistent with this hypothesis, MCM proteins can form hexameric complexes that possess ATP-dependent DNA unwinding activity. The molecular mechanism by which the energy of ATP hydrolysis is harnessed to DNA unwinding is unknown, although the ATPase activity has been attributed to a highly conserved AAA+ family ATPase domain. Here we show that changes to N- and C-terminal motifs in the single MCM protein from the archaeon
Methanothermobacter thermautotrophicus
(
Mth
MCM) can modulate ATP hydrolysis, DNA binding, and duplex unwinding. Furthermore, these motifs appear to influence the movement of the β-α-β insert in helix-2 of the MCM ATPase domain. Removal of this motif from
Mth
MCM increased dsDNA-stimulated ATP hydrolysis and increased the affinity of the mutant complex for ssDNA and dsDNA. Deletion of the helix-2 insert additionally resulted in the abrogation of DNA unwinding. Our results provide significant insight into the molecular mechanisms used by the MCM helicase to both regulate and execute DNA unwinding.
The Evolutionarily Conserved Tetratrico Peptide Repeat Protein Pale Yellow Green7 Is Required for Photosystem I Accumulation in Arabidopsis and Copurifies with the Complex
Authors: Stöckel Jana , Bennewitz Stefan , Hein Paul , Oelmüller Ralf
Published: May 2006

Pale yellow green 7-1 (pyg7-1) is a photosystem I (PSI)-deficient Arabidopsis (Arabidopsis thaliana) mutant. PSI subunits are synthesized in the mutant, but do not assemble into a stable complex. In contrast, light-harvesting antenna proteins of both photosystems accumulate in the mutant. Deletion of Pyg7 results in severely reduced growth rates, alterations in leaf coloration, and plastid ultrastructure. Pyg7 was isolated by map-based cloning and encodes a tetratrico peptide repeat protein with homology to Ycf37 from Synechocystis. The protein is localized in the chloroplast associated with thylakoid membranes and copurifies with PSI. An independent pyg7 T-DNA insertion line, pyg7-2, exhibits the same phenotype. pyg7 gene expression is light regulated. Comparison of the roles of Ycf37 in cyanobacteria and Pyg7 in higher plants suggests that the ancient protein has altered its function during evolution. Whereas the cyanobacterial protein mediates more efficient PSI accumulation, the higher plant protein is absolutely required for complex assembly or maintenance.
Illumination Is Necessary and Sufficient to Induce Histone Acetylation Independent of Transcriptional Activity at the C4-Specific Phosphoenolpyruvate Carboxylase Promoter in Maize
Authors: Offermann Sascha , Danker Tanja , Dreymüller Daniela , Kalamajka Rainer , Töpsch Sonja , Weyand Katrin , Peterhänsel Christoph
Published: May 2006

Expression of the C4-specific phosphoenolpyruvate carboxylase (C4-PEPC) gene in maize (Zea mays) is regulated in a tissue-specific manner, but affected by light and nutrient availability. We manipulated these stimuli in a combinatorial manner and analyzed concomitant changes in histone acetylation of the nucleosomes associated with the C4-PEPC gene in relation to transcriptional activity and steady-state mRNA levels. Whereas the transition from the lowest activity to an intermediate activity was observed in the absence of histone acetylation, the light-induced boost to full activity was associated with strong enhancement of the acetylation of both histones H3 and H4 limited to the gene region. Once activated by light, prolonged darkness was necessary to reduce both transcription and, in parallel, histone acetylation. Unexpectedly, histone acetylation was also induced in bundle sheath cells, although the transcriptional activity did not respond to illumination in this tissue. Furthermore, we were able to down-regulate the promoter by nitrogen depletion in the light without any decrease in the hyperacetylation of histone H4. When plants kept in prolonged darkness were nitrogen depleted and then exposed to light, transcription was not induced, but the promoter chromatin became hyperacetylated. We suggest a model where inhibition of a histone deacetylase in the light triggers H4 hyperacetylation at the C4-PEPC gene promoter regardless of the transcriptional activity of the gene. Our data indicate that an understanding of the interplay between histone modification and transcription requires analysis of signal integration on promoters in vivo.
The π-donor 4,5;4′,5′-bis(dioxane-1,4-diyl-2,3-dithio)tetrathiafulvalene
Authors: Malfant Isabelle , Vendier Laure , D'Yachenko Oleg A. , Kotov Alexander I.
Published: May 2006

The title molecule, C14H12O4S8, has a U-shaped conformation and its crystal structure feaures short intermolecular S...S contacts.
Ethyl 5-amino-1-(5-amino-3-methyl-1-phenyl-1H-pyrazol-4-ylcarbonyl)-3-methyl-1H-pyrazole-4-carboxylate
Authors: Li Jun-Fei , Song Hai-Bin , Zhu You-Quan , Yang Hua-Zheng
Published: May 2006

The crystal structure of the title compound, C18H20N6O3, is stabilized by N—H...O and N—H...N hydrogen bonds.
1-(2,4-Dichlorophenyl)-3-(4-methoxyphenyl)prop-2-en-1-one
Authors: Patil P. S. , Rosli Mohd Mustaqim , Fun Hoong-Kun , Razak Ibrahim Abdul , Dharmaprakash S. M. , Shettigar Venkataraya
Published: May 2006

In the title compound, C16H12Cl2O2, the dihedral angle between the benzene rings is 44.59 (3)°. In the crystal structure, the molecules form layers parallel to the ac plane which propagate down the b axis and which are stabilized by short Cl...Cl interactions.
(E)-2-Hydroxy-3-methoxy-5-[(3-methoxyphenyl)diazenyl]benzaldehyde
Authors: Karadayı Nevzat , Albayrak Çiğdem , Odabaşoğlu Mustafa , Büyükgüngör Orhan
Published: May 2006

The molecule of the title compound, C15H14N2O4, is approximately planar and displays a trans configuration with respect to the N=N double bond. The molecules are linked by intermolecular C—H...O and C—H...π interactions, forming a three-dimensional network.
catena-Poly[[aquachlorodimethylformamidecopper(II)]-μ-chloro]
Authors: Zhang Qi-Wei , Wen Yi-Hang , Feng Yun-Long
Published: May 2006

In the title complex, [CuCl2(C3H7NO)(H2O)]
n
, each CuII atom is in a Cl3O2 five-coordinate environment with a slightly distorted square-pyramidal geometry. Cu atoms are linked by μ2-Cl ions, resulting in a one-dimensional linear chain structure. In the crystal structure, intermolecular O—H...Cl hydrogen bonds link adjacent chains to form a two-dimensional network.
Poly[aquabis(μ4-benzene-1,2-dicarboxylato)(μ3-benzene-1,2-dicarboxylato)digadolinium(III)]
Authors: Meng Ze-Rong , Zhang Quan-Zheng , Wu Xiao-Yuan , Chen Li-Juan , Lu Can-Zhong
Published: May 2006

The title compound, [Gd2(C8H4O4)3(H2O)]
n
, is a two-dimensional coordination polymer. The Gd atoms are eight- and nine-coordinated. This compound is isostructural with its dysprosium analog.
Phenyltris(pyrimidine-2-thiolato)tin(IV)
Authors: Li Yong-Xin , Zhang Ru-Fen , Ma Chun-Lin
Published: May 2006

The seven-coordinate Sn atom in the monomeric title compound, [Sn(C6H5)(C4H3N2S)3], has distorted pentagonal–bipyramidal geometry. The axial C—Sn—S angle is 154.10 (7)°. Thiolate S and phenyl C atoms define the axial positions. Two S atoms and three N atoms define the pentagonal equatorial plane.
Diethyl 3,3′-(cis-[4a]-cisoid-[4a,4b]-cis-[4b]-9,11-dimethyl-2,4,6,8-tetraoxoperhydrocyclobuta[1,2-d:3,4-d]dipyrimidine-1,5-diyl)dipropionate
Authors: Tang Wen-Jian , Song Qin-Hua
Published: May 2006

In the title compound, C20H28N4O8, the two methyl groups attached to the cyclobutane ring are cis oriented. The crystal structure is stabilized by intermolecular N—H...O hydrogen bonds.
4-Benzylidene-2-diethylamino-1-phenyl-1H-imidazol-5(4H)-one
Authors: Li Gui-Hua , Hu Yang-Gen
Published: May 2006

In the crystal structure of the title compound, C20H21N3O, intramolecular C—H...N hydrogen bonds stabilize the conformation of the molecule.
N-(4-Chloro-3-nitrophenyl)-N′-(3-nitrobenzoyl)thiourea
Authors: Yusof M. Sukeri M. , Rahim S. Sarah A. , Yamin Bohari M.
Published: May 2006

In the title molecule, C14H9ClN4O5S, all bond lengths and angles show normal values. The mean plane of the central thiourea unit, N2CS, makes dihedral angles of 9.54 (12) and 56.60 (10)°, respectively, with the mean planes of the 3-nitrobenzoyl and 4-chloro-3-nitrophenyl groups. The crystal packing is stabilized by weak intermolecular N—H...O and C—H...O hydrogen bonds.
5-{[4-(4-Bromophenyl)thiazol-2-yl]aminomethylene}-2,2-dimethyl-1,3-dioxane-4,6-dione
Authors: Silva Luiz Everson da , Joussef Antonio Carlos , Foro Sabine , Schmidt Boris
Published: May 2006

In the title compound, C16H13BrN2O4S, the 1,3-dioxane-4,6-dione ring exhibits an envelope conformation. The amino H atom makes an intramolecular contact to a carbonyl O atom, forming a six-membered ring.