bluuebunny/crossref_metadata_2025 huggingface dataset:
The repertoire of testicular extracellular vesicles cargoes and their involvement in inter-compartmental communication required for spermatogenesis
Authors: Choy Kathleen Hoi Kei , Chan Sze Yan , Lam William , Jin Jing , Zheng Tingting , Yu Sidney Siubun , Wang Weiping , Li Linxian , Xie Gangcai , Yim Howard Chi Ho , Chen Hao , Fok Ellis Kin Lam
Published: January 2021

Extracellular vesicles (EVs) secreted by the epididymis and prostate are involved in sperm functions and epigenetic inheritance. However, the EVs in the testis remains unexplored. Here, we have established a testis dissociation protocol that allows the isolation of testicular EVs by minimizing the disruption of fragile sperm cells. We showed that testicular EVs were specifically and efficiently uptaken by somatic cells and germ cells in both interstitial space and seminiferous tubules compartments, including the spermatozoa. We profiled the proteome of testicular EVs and probed the cell types that release them. Moreover, we sequenced the small RNAs cargos of testicular EVs and identified sets of small non-coding RNAs that were overlooked in the testis transcriptome. Selected miRNA candidates in testicular EVs were found in sperm RNA payload and demonstrated specific resistance towards ribonuclease A independent of the vesicle membrane. Small molecule inhibition of EVs secretion increased the apoptosis of germ cells via inter-compartmental communication. Together, our study has provided valuable resources on the cargoes of testicular EVs and revealed the inter-compartmental communication that regulates spermatogenesis and may implicate in paternal inheritance.
AncestralClust: Clustering of Divergent Nucleotide Sequences by Ancestral Sequence Reconstruction using Phylogenetic Trees
Authors: Pipes Lenore , Nielsen Rasmus
Published: January 2021

Motivation

Clustering is a fundamental task in the analysis of nucleotide sequences. Despite the exponential increase in the size of sequence databases of homologous genes, few methods exist to cluster divergent sequences. Traditional clustering methods have mostly focused on optimizing high speed clustering of highly similar sequences. We develop a phylogenetic clustering method which infers ancestral sequences for a set of initial clusters and then uses a greedy algorithm to cluster sequences.

Results

We describe a clustering programAncestralClust, which is developed for clustering divergent sequences. We compare this method with other state-of-the-art clustering methods using datasets of homologous sequences from different species. We show that, in divergent datasets, AncestralClust has higher accuracy and more even cluster sizes than current popular methods.

Availability and implementation

AncestralClust is an Open Source program available athttps://github.com/lpipes/ancestralclust.

Contact

lpipes@berkeley.edu

Supplementary information

Supplementary figures and table are available online.
Long-lasting reduction of intrinsic excitability in O-LM interneurons is mediated by endocannabinoid-dependent up-regulation of Kv7 channels
Authors: Incontro Salvatore , Sammari Malika , Ankri Norbert , Russier Michael , Fantini Jacques , Debanne Dominique
Published: January 2021

KCNQ-Kv7 channels are found at the axon initial segment of pyramidal neurons where they control cell firing and membrane potential. In oriens lacunosum moleculare (O-LM) interneurons, these channels are mainly expressed in the dendrites, suggesting a peculiar function of Kv7 channels in these neurons. The physiology of Kv7 channels is well characterized today but the precise contribution of these channels to neuronal plasticity is still unknown. Here, we show that Kv7 channel activity is up-regulated following induction of presynaptic long-term synaptic depression (LTD) in O-LM interneurons, thus resulting in a synergistic long-term depression of intrinsic neuronal excitability (LTD-IE). Both LTD and LTD-IE involve endocannabinoid (eCB) biosynthesis for their induction. Molecular modeling shows strong interaction of eCBs with Kv7.2/3 channel, suggesting a persistent action of these lipids on Kv7 channel activity. Our data thus unveil a major role for eCB synthesis in triggering both synaptic and intrinsic depression in O-LM interneurons.
Gut microbiome features are associated with sepsis onset and outcomes
Authors: Rao Krishna , Patel Alieysa R. , Seekatz Anna M. , Bassis Christine M. , Sun Yuang , Henig Oryan , Albin Owen R , SantaLucia John , Woods Robert , Bachman Michael A.
Published: January 2021

Background

Epidemiologic studies have linked antibiotic exposure to subsequent sepsis, suggesting that microbiome disruption may be in the causal pathway and an independent risk factor. This study tests whether variation in the gut microbiota associates with risk of sepsis onset and its outcomes.

Methods

Using a validated surveillance definition, patients with an archived rectal swab from intensive care and hematology units were screened for sepsis. After confirmation by chart review, cases were matched to controls in a 1:2 ratio based on age, gender, and collection date. Relative taxon abundance was measured by sequence analysis of 16S rRNA gene amplicons; total bacterial abundance was measured by qPCR of the 23S rRNA gene. Conditional logistic regression identified clinical and microbiota variables associated with sepsis.

Results

There were 103 sepsis cases matched to 206 controls. In a final model adjusting for exposure to broad-spectrum antibiotics and indwelling vascular catheters, high relative abundance (RA) ofEnterococcus(Odds Ratio (OR) 1.36 per 10% increase,P=.016) and high total bacterial abundance (OR 1.50 per 10-fold increase in 23S copies/μL,P=.001) were independently associated with sepsis. Decreased RA of butyrate-producing bacteria also independently associated with sepsis (OR 1.20 for 10% decrease in RA,P=.041), and mortality in unadjusted analysis (OR=1.47 for 10% decrease in RA,P=.034).

Conclusions

This study indicates that the microbiota is altered at sepsis onset. The decreased RA of butyrate-producing bacteria in sepsis also associates with mortality, suggesting a therapeutic role for prebiotics and probiotics in the prevention and treatment of sepsis.

Importance

Early detection of patients at risk for sepsis could enable interventions to prevent or rapidly treat this life-threatening condition. Prior antibiotic treatment is associated with sepsis, suggesting that disruption of the bacterial population in the gut (the intestinal microbiome) could be an important step leading to disease. To investigate this theory, we matched hospitalized patients with and without sepsis and characterized the patients’ microbiomes close to or at onset of sepsis. We found that several microbiome alterations, including having more total bacteria in the gut was associated with onset, regardless of prior antibiotic treatment. This signature of microbiome disruption brings us closer to identifying the biological causes of sepsis and could be used to develop new diagnostic tests to identify patients at risk of sepsis.
Elucidating the CodY regulon inStaphylococcus aureusUSA300 substrains
Authors: Gao Ye , Poudel Saugat , Seif Yara , Shen Zeyang , Palsson Bernhard O.
Published: January 2021

CodY is a conserved broad acting transcription factor that regulates the expression of genes related to amino acid metabolism and virulence in methicillin-resistantStaphylococcus aureus(MRSA). CodY target genes have been studied by usingin vitroDNA affinity purification and deep sequencing (IDAP-Seq). Here we performed the firstin vivodetermination of CodY target genes using a novel CodY monoclonal antibody in established ChIP-exo protocols. Our results showed, 1) the same 135 CodY promoter binding sites regulating 165 target genes identified in two closely related virulentS. aureusUSA300 TCH1516 and LAC strains; 2) The differential binding intensity for the same target genes under the same conditions was due to sequence differences in the same CodY binding site in the two strains; 3) Based on transcriptomic data, a CodY regulon comprising 72 target genes that are differentially regulated relative to a CodY deletion strain, representing genes that are mainly involved in amino acid transport and metabolism, inorganic ion transport and metabolism, transcription and translation, and virulence; and 4) CodY systematically regulated central metabolic flux to generate branched-chain amino acids (BCAAs) by mapping the CodY regulon onto a genome-scale metabolic model ofS. aureus. Our study performed the first system-level analysis of CodY in two closely related USA300 TCH1516 and LAC strains giving new insights into the similarities and differences of CodY regulatory roles between the closely related strains.

Importance

With the increasing availability of whole genome sequences for many strains within the same pathogenic species, a comparative analysis of key regulators is needed to understand how the different strains uniquely coordinate metabolism and expression of virulence. To successfully infect the human host,Staphylococcus aureusUSA300 relies on the transcription factor CodY to reorganize metabolism and express virulence factors. While CodY is a known key transcription factor, its target genes are not characterized on a genome-wide basis. We performed a comparative analysis to describe the transcriptional regulation of CodY between two dominant USA300 strains. This study motivates the characterization of common pathogenic strains and an evaluation of the possibility of developing specialized treatments for major strains circulating in the population.
Cancer risk and sexual conflict as constraints to body size evolution
Authors: Erten E. Yagmur , Kokko Hanna
Published: January 2021

Selection often favours large bodies, visible as Cope’s rule over macroevolutionary time — but size increases are not inevitable. One understudied cost of large bodies is the high number of cell divisions and the associated risk of oncogenic mutations. Our elasticity analysis shows that selection against a proportional increase in size becomes ever more intense with increasing body size if cancer is the sole selective agent. Thus cancer potentially halts body size increases even if no other constraint does so. We then provide multicellular realism with potentially sexually dimorphic body sizes and traits that control cell populations from zygote to maturity and beyond (ontogenetic management). This shows sexual conflict to extend to ontogeny; sexual dimorphism in mortalities and other life history measures may evolve even in the absence of any ecological causes underlying size- or sex-dependent mortality. Coadaptation of ontogenetic management and body size is required for substantial increases in size.
Single cell analyses reveal distinct adaptation of typhoidal and non-typhoidalSalmonella entericaserovars to intracellular lifestyle
Authors: Reuter Tatjana , Scharte Felix , Franzkoch Rico , Liss Viktoria , Hensel Michael
Published: January 2021

Salmonella entericais a common foodborne, facultative intracellular enteropathogen. Human-restricted typhoidalS. entericaserovars Typhi (STY) or Paratyphi A (SPA) cause severe typhoid or paratyphoid fever, whileS. entericaserovar Typhimurium (STM) has a broad host range and in human hosts usually lead to a self-limiting gastroenteritis. Due to restriction of STY and SPA to primate hosts, experimental systems for studying the pathogenesis of typhoid and paratyphoid fever are limited. Therefore, STM infection of susceptible mice is commonly considered as model system for studying these diseases. The type III secretion system encoded bySalmonellapathogenicity island 2 (SPI2-T3SS) is a key factor for intracellular survival ofSalmonella. Inside host cells, the pathogen resides within theSalmonella-containing vacuole (SCV) and induces tubular structures extending from the SCV, termedSalmonella-induced filaments (SIF). This study applies a set of single cell analyses approaches such as dual fluorescent protein reports, effector translocation, or correlative light and electron microscopy to investigate the fate and activities of intracellular STY and SPA. The SPI2-T3SS of STY and SPA is functional in translocation of effector proteins, SCV and SIF formation. However, only a low proportion of intracellular STY and SPA are actively deploying SPI2-T3SS and STY and SPA exhibited a rapid decline of protein biosynthesis upon experimental induction. A role of SPI2-T3SS for proliferation of STY and SPA in epithelial cells was observed, but not for survival or proliferation in phagocytic host cells. Our results indicate that reduced intracellular activities are factors of the stealth strategy of STY and SPA and facilitate systemic spread and persistence of the typhoidalSalmonella.
Signatures of Mutational Processes in Human DNA Evolution
Authors: Hamidi Hamid , Alinejad-Rokny Hamid , Coorens Tim , Sanghvi Rashesh , Lindsay Sarah J , Rahbari Raheleh , Ebrahimi Diako
Published: January 2021

The human genome contains over 100 million SNPs, most of which are C/T (G/A) variations. The type and sequence context of these SNPs are not random, suggesting that they are caused by distinct mutational processes. Deciphering the mutational signatures is a crucial step to discovering the molecular processes responsible for DNA variations across human populations, and potentially for causing genetic diseases. Our analyses of the 1000 Genomes Project SNPs and germlinede novomutations suggest that at least four mutational processes are responsible for human genetic variations. One process is European-specific and no longer active. The remaining three processes are currently active in all human populations. Two of the active processes co-occur and leave a single joint mutational signature in human nuclear DNA. The third active process is specific to mitochondrial DNA, and inflicts C-to-T mutations at mostly non-CG sites. We found neither evidence of APOBEC-induced cytosine deamination in the human germline, norde novomutation enrichment within certain regions of the human genome.
PepNN: a deep attention model for the identification of peptide binding sites
Authors: Abdin Osama , Nim Satra , Wen Han , Kim Philip M.
Published: January 2021

Protein-peptide interactions play a fundamental role in facilitating many cellular processes, but remain underexplored experimentally and difficult to model computationally. Here, we present PepNN-Struct and PepNN-Seq, structure and sequence-based approaches for the prediction of peptide binding sites on a protein given the sequence of a peptide ligand. A main difficulty for the prediction of peptide-protein interactions is the flexibility of peptides and their tendency to undergo conformational changes upon binding. To account for this behaviour, we developed a novel reciprocal attention module that simultaneously updates the encodings of peptide and protein residues and explicitly enforces the symmetry in the updates, allowing for information flow and reflecting the biochemical reality of conformational changes in the peptide. PepNN additionally makes use of modern graph neural network layers that are effective at learning representations of molecular structure. Finally, to compensate for the scarcity of peptide-protein complex structural information, we make use of available protein-protein complex and protein sequence information through a series of transfer learning steps. PepNN-Struct achieves state-of-the-art performance on the task of identifying peptide binding sites, with a ROC AUC of 0.893 and an MCC of 0.483 on an independent test set. Beyond prediction of binding sites on proteins with a known peptide ligand, we also show that the developed models make reasonable peptide-agnostic predictions, allowing for the identification of novel peptide binding proteins.
Deciphering 3D Human Sphygmopalpation Pulse Patterns using “X-ray” Images Acquired from Tactile Robotic Fingers
Authors: Kong Ka Wai , Chan Ho-yin , Xie Jun , Lee Francis Chee Shuen , Leung Alice Yeuk Lan , Guan Binghe , Shen Jiangang , Wong Vivian Chi-Woon Taam , Li Wen J.
Published: January 2021

Sphygmopalpationat specific locations of human wrists has been used as a medical measurement technique in China since the Han Dynasty (202 BC - 220 AD); it is now generally accepted that traditional Chinese medicine (TCM) doctors are able to decipher 28 types of basic pulse patterns using their fingertips. This TCM technique of examining individual arterial pulses by palpation has undergone an upsurge recently in popularity as a low-cost and non-invasive diagnostic technique for monitoring patient health status. We have developed a pulse sensing platform for studying and digitalizing arterial pulse patterns via a TCM approach. This platform consists of a robotic hand with three fingers for pulse measurement and an artificial neural network (ANN) together with pulse signal preprocessing for pulse pattern recognition. The platforms previously reported by other research groups or marketed commercially exhibit one or more of the following imperfections: a single channel for data acquisition, low sensitivity and rigid sensors, lack of control of the applied pressure, and in many reported works, lack of an intelligent data analysis system. The platform presented here features up to three-dimensional (3D) tactile sensing channels for recording data and uses highly sensitive capacitive MEMS (microelectromechanical systems) flexible sensing arrays, pressure-feedback-controlled robotic fingers, and machine learning algorithms. We also proposed a methodology of obtaining “X-ray” image of pulse information constructed based on the sensing data from 3 locations and 3 applied pressures (i.e., mimicking TCM doctors), which contains all arterial pulse information in both spatial and temporal spans, and which could be used as an input to a deep learning algorithm. By applying our developed platform and algorithms, 3 types of consistent pulse patterns, i.e., “Hua”, “Xi”, and “Chen”, as described by TCM doctors”, could be identified in a selected group of 3 subjects who were diagnosed by TCM practitioners. We have shown the classification rates is 98.7% in training process and 84.2% in testing result for these 3 basic pulse patterns. The high classification rate of the developed platform could lead to further development of a high-level artificial intelligence system incorporating knowledge from TCM – the robotics finger system could become a standard clinical equipment for digitalizing and visualizing human arterial pulses
Microwave absorption performance of hexagonal nano boron nitride doped basalt fabric-reinforced epoxy composites
Authors: Bakal Fatma , Yapici Ahmet , Karaaslan Muharrem , Akgöl Oğuzhan
Published: January 2021

Purpose

The purpose of this paper is to investigate the effect of doping element on the microwave absorption performance of hexagonal nano boron nitride (h-nBN)-reinforced basalt fabric (BF)/epoxy composites. A new type of hybrid composite that will be produced by the use of boron nitride as an additive that leads to increased radar absorption capability will be developed and a new material that can be used in aeronautical radar applications.

Design/methodology/approach

This study is focused on the microwave absorption properties of h-nBN doped basalt fabric-reinforced epoxy composites. Basalt fabric (BF)/epoxy composites (pure composites) and the BF/h-nBN (1 Wt.% h-nBN doped composites) hybrid composites were fabricated by vacuum infusion method. Phase identification of the composites were performed using X-ray diffraction (XRD), the 2θ scan range was from 10 to 60 with the scanning speed of 3°/min and surface morphologies of the composites were investigated using scanning electron microscopy (SEM). Microwave properties of samples were investigated through transmission/reflection measurements in Agilent brand 2-Port PNA-L Network Analyzer in the frequency range of 3–18 GHz. The prepared sample is positioned between two horn antennas with and without metal plate.

Findings

Experimental results show that h-nBN doped composite was synthesized successfully and the produced hexagonal nano boron nitride-added fiber laminated composite material has good absorption behavior when they are used with metallic sheets and good for isolation applications at many points in the 3–18 GHz band.

Originality/value

This paper will contribute to the literature on the use of basalt fabric, which are new types of fibers, and hexagonal nano boron nitride and the effects of boron nitride on radar absorption properties of composite material. It presents detail characterization of each composite by using XRD and scanning electron microscopy.
The impact of leanness on supply chain sustainability: examining the role of sustainability control systems
Authors: Rupasinghe Hasitha Dinithi , Wijethilake Chaminda
Published: January 2021

Purpose

An alignment between financial and operational measures is an essential element to capture the lean productivity improvements enabling supply chain sustainability. With the aim of supporting small and medium-sized enterprises (SMEs) in addressing corporate sustainability challenges, this study aims to examine the impact of leanness on supply chain sustainability, and the moderating role of sustainability control systems (SCS) on the relationship between leanness and supply chain sustainability.

Design/methodology/approach

Drawing on lean manufacturing and the levers of control framework, survey data was collected from 106 manufacturing SMEs in Sri Lanka. Moderated multiple regression analysis was used to test the proposed hypotheses.

Findings

The study finds that lean manufacturing practices, such as just-in-time deliveries, quality management, environmental management and employee involvement show a significant positive impact on supply chain sustainability. As proposed, the interactive use of SCS shows a significant, positive moderating impact on the relationship between employee involvement and social supply chain sustainability. The diagnostic use of SCS negatively moderates the relationships between just-in-time deliveries and economic supply chain sustainability, and environmental management and economic supply chain sustainability. However, both interactive and diagnostic uses of SCS do not show any significant moderating impact between lean manufacturing and environmental supply chain sustainability.

Research limitations/implications

The following limitations should be taken into account in interpreting the results and implications of this study. Firstly, the study refers to supply chain sustainability as environmental, social and economic sustainability. As these concepts represent broader perspectives of sustainability, and no consensus on how to measure has yet been agreed, future studies may focus on other variables that might capture different perspectives of supply chain sustainability. Secondy, future researchers may further extend the role of SCS (including all four control systems – belief, boundary, interactive and diagnostic) in examining the impact of leanness on supply chain sustainability. Thirdly, this study has considered a sample of manufacturing SMEs in the Western province in Sri Lanka. The results should be carefully generalised to other manufacturing organisations in Sri Lanka and beyond. Finally, future studies may also investigate the impact of leanness on supply chain sustainability by using alternative methodologies, such as multiple case studies.

Originality/value

SMEs are more likely to focus on diagnostic control systems with the aim of promoting economic supply chain sustainability. However, the findings reveal that manufacturing SMEs in the developing country context lack strong SCS to enable supply chain sustainability.
Tracking major resources for automated progress monitoring of construction activities: masonry work case
Authors: Guven Gursans , Ergen Esin
Published: January 2021

Purpose

The purpose of this study is to monitor the progress of construction activities in an automated way by using sensor-based technologies for tracking multiple resources that are used in building construction.

Design/methodology/approach

An automated on-site progress monitoring approach was proposed and a proof-of-concept prototype was developed, followed by a field experimentation study at a high-rise building construction site. The developed approach was used to integrate sensor data collected from multiple resources used in different steps of an activity. It incorporated the domain-specific heuristics that were related to the site layout conditions and method of activity.

Findings

The prototype estimated the overall progress with 95% accuracy. More accurate and up-to-date progress measurement was achieved compared to the manual approach, and the need for visual inspections and manual data collection from the field was eliminated. Overall, the field experiments demonstrated that low-cost implementation is possible, if readily available or embedded sensors on equipment are used.

Originality/value

Previous studies either monitored one particular piece of equipment or the developed approaches were only applicable to limited activity types. This study demonstrated that it is technically feasible to determine progress at the site by fusing sensor data that are collected from multiple resources during the construction of building superstructure. The rule-based reasoning algorithms, which were developed based on a typical work practice of cranes and hoists, can be adapted to other activities that involve transferring bulk materials and use cranes and/or hoists for material handling.
Using Mendelian randomization to evaluate the effects of alcohol consumption on the risk of coronary heart disease
Authors: Ellison R. Curtis , Grønbæk Morten , Skovenborg Erik
Published: January 2021

Purpose

This paper aims to evaluate the use of Mendelian randomization (MR) analyses for judging the effects of alcohol consumption on the risk of coronary heart disease (CHD).

Design/methodology/approach

This paper presents a review of methodology for MR and describes its early application to judging health effects of alcohol, current uses and a recommended approach of combining MR results with those from observational and experimental studies.

Findings

Early applications of MR to health effects of alcohol consumption were inadequate for providing unbiased results, but newer attempts using polygenic scores show promise. It is important to combine data from MR analyses with those from observational and experimental studies to obtain an unbiased and scientifically sound estimate of alcohol’s effects on health.

Practical implications

Giving advice to the public regarding alcohol consumption must be based on accurate, unbiased scientific data; this paper describes attempts to use MR for achieving this goal.

Social implications

Given that light-to-moderate alcohol intake is associated with a lower risk of CHD, type II diabetes mellitus and total mortality, it is important to be able to evaluate both the benefits and harms from alcohol before giving advice regarding drinking.

Originality/value

This is part of a group of three papers dealing with the potential health benefits and harms associated with alcohol consumption.
Creation and dissemination of hospitality and tourism research outputs in the new millennium
Authors: Wong Antony King Fung , Koseoglu Mehmet Ali , Kim Seongseop (Sam)
Published: January 2021

Purpose

This study aims to examine the current state of the research activities of scholars in the hospitality and tourism field by analyzing the first 20 years of the new millennium.

Design/methodology/approach

Longitudinal analyses using 14,229 journal articles as data source were realized by adopting BibExcel, Gephi and VOSviewer network analysis software packages.

Findings

This study provides a comprehensive overview of the hospitality and tourism research based on authorship and social network analysis, with patterns of prolific authors compared over four distinct periods.

Research limitations/implications

The hospitality and tourism academic society is clearly illustrated by tracing academic publication activities across 20 years in the new millennium. In addition, this study provides a guide for scholars to search for multidisciplinary collaboration opportunities. Government agencies and non-governmental organisations can also benefit from this study by identifying appropriate review panel members when making decisions about hospitality- and tourism-related proposals.

Originality/value

To the best of authors’ knowledge, this study is the first to use bibliometric analysis in assessing research published in leading hospitality and tourism journals across the four breakout periods in the new millennium.
Hedonic housing prices and environmental quality in Lebanon
Authors: Marrouch Walid , Sayour Nagham
Published: January 2021

Purpose

This study aims to examine the impact of local air pollution on housing prices in Lebanon.

Design/methodology/approach

The authors apply a hedonic pricing approach using a unique data set from Lebanon. To account for non-linearities in pricing, the authors use three different functional regression forms for the hedonic model approach. The authors also deal with potential omitted variable bias by estimating a hedonic frontier specification.

Findings

The authors find that, in all specifications, air pollution negatively and significantly affects housing prices. The estimated marginal willingness to pay for a one microgram per cubic meter change in particulate matter (PM10) concentration ranges between 2.88% and 3.18% of mean housing prices. The authors also provide evidence of a negative pricing gradient away from the city center, landing support for the monocentric urban development hypothesis.

Research limitations/implications

Given the lack of a data set linking household socioeconomic characteristics with housing data, the authors only consider the first-stage hedonic model.

Practical implications

The proposed hedonic pricing regression approximates a housing pricing equation that can be used by policymakers.

Social implications

The findings suggest that pollution is a significant factor in household behavior in Lebanon.

Originality/value

This paper adds to the scant literature studying the effects of air pollution on housing prices in developing countries. To the best of the authors’ knowledge, this is the first paper to study the impact of pollution on housing prices in a country in the Middle East and North Africa Region.
Determinants of foreign exchange reserve accumulation: empirical evidence from foreign exchange constrained economy
Authors: Gereziher Hayelom Yrgaw , Nuru Naser Yenus
Published: January 2021

Purpose

The main purpose of this study is to investigate the determinants of foreign exchange reserve accumulation in a foreign exchange constrained economy, namely Ethiopia, over the period of 1981 up to 2017.

Design/methodology/approach

In this study, autoregressive distributed lag (ARDL) model is used. Besides, standard unit-root tests such as augmented Dickey Fuller (ADF) and Phillips–Perron (PP) tests are employed to check for the stationarity of the series.

Findings

According to the results of unit-root tests, our variables are found to be a mixture of I(0) and I(1), and none of our series is I(2). The results of our ARDL model indicates, in the short run, foreign exchange reserve accumulation of Ethiopia is negatively and significantly affected by inflation rate and exchange rate. But, in the long run, inflation rate affects foreign exchange reserve positively and significantly. Additionally, in the long run, external debt affects foreign exchange reserve positively. Similar to its effect in the short run, exchange rate also affects foreign exchange reserve negatively in the long run.

Originality/value

This paper has its originality as it contributes in reasoning out the factors determining, both in the short-run and long-run, foreign exchange deficiency in any developing country with foreign exchange deficiency, taking Ethiopian economy as a case study, and fills the scarce literature on the determinants of foreign exchange reserve accumulation in a developing country.
Economic policy uncertainty and hotel occupancy: the mediating effect of consumer sentiment
Authors: Ozdemir Ozgur , Han Wenjia , Dalbor Michael
Published: January 2021

Purpose

The purpose of this paper is twofold. First, the study examines the prolonged effect of policy-related economic uncertainty on hotel operating performance, particularly the room demand (occupancy). Second, the study attempts to explain why occupancy drops when the perceived economic uncertainty is high by studying the mediating effect of consumer sentiment in the relationship between economic policy uncertainty and hotel demand.

Design/methodology/approach

This quantitative study uses secondary data – US economic policy uncertainty (EPU) index, University of Michigan's index of consumer sentiment (ICS), and property-level hotel operating data from three states of the US – California, Florida and New York. Data were analyzed using random effect regression and structural equation modeling. Robustness tests were conducted to enhance the reliability of the research findings.

Findings

Random-effects regression analysis reveals that policy-related economic uncertainty has a negative and lead-lag effect on hotel occupancy, average daily rate and revenue per available room (RevPAR). Structural equation modeling results show that the relationship between economic policy uncertainty and hotel occupancy is significantly mediated by consumer sentiment. Robustness test results support the findings from the main analysis.

Practical implications

This study offers valuable implications for the hotel professionals in regard to anticipating the economic impact of policy-related uncertainty on hotel industry and understanding how consumer sentiment affects demand at such crises times. Moreover, the study suggests potential course of actions to deal with declining room demand at times of uncertainty.

Originality/value

This empirical study explores how economic policy uncertainty affects hotel performance at the property level and explains the mediating effect of consumer sentiment on hotel room demand. The study provides a first-hand evidence of how consumer sentiment relates to the perception of economic uncertainty and leads to decline in consumer demand. In that regard, findings of the study have valuable implications for hospitality industry practitioners and relevant policymakers.
The effects of inter-organizational compatibility on knowledge transfer in cross-border M&As
Authors: Qi Ying , Wang Xiangyang , Li Yujia , Zhang Gongyi , Jin Huiqi
Published: January 2021

Purpose

The study adopts congruence theory to explore the structure of inter-organizational compatibility and its structural effects on knowledge transfer in cross-border merger and acquisitions (M&As).

Design/methodology/approach

This paper built a moderated-mediation model that presented the relationship between inter-organizational compatibility and knowledge transfer. Regression analysis was conducted with 182 samples from China to examine the model and hypotheses.

Findings

The results indicate that inter-organizational compatibility is a four-dimensional construct comprising culture, strategy, routine and knowledge. Additionally, inter-organizational compatibility has structural effects on knowledge transfer. Specifically, routine compatibility mediates the relationships between cultural compatibility and knowledge transfer and between strategic compatibility and knowledge transfer. Moreover, the mediating roles are moderated by knowledge compatibility.

Originality/value

This study updates the construct and provides a comprehensive and fresh understanding of inter-organizational compatibility. Additionally, it presents the structural effects of inter-organizational compatibility on knowledge transfer.
Open Building, Energy and Sustainability: The Import of Leed™ Rating
Authors: Koester Robert J.
Published: January 2021

This paper addresses opportunities available for meeting sustainability objectives in building construction by using the conceptual alignments of Open Building and LEED™ Rating. These two systems utilize hierarchical, scalar categorizations to structure issues of design as a set of nested constructs and function as methodologies for affecting both problem definition and the management of strategic design process.

Each system addresses the distribution of control in the design decision−making process as a positioning of decisions in space and time. Establishing the correlation of the two systems can facilitate the conversation among all participants involved in the origination, construction, use, and management of buildings−and their systems−as they seek to assure the sustainability of what they design, build, and use.
Reconstruction of Satisfactory and Culturally Appropriate Neighbourhoods in Turkey
Authors: Saglamer Gülsün , Velioglu Selim , Türkoglu Handan Dülger , Dikbas Atilla , Erkut Gülden , Berk Özlem
Published: January 2021

In the year 2000, a team from Istanbul Technical University (ITU) developed the “Urban m3 - Respect for Life Project”, which was aimed at providing shelter for those people who were left homeless as a consequence of the earthquake in 1999, in the districts of Arizli-Kocaeli in Turkey. This earthquake had a catastrophic effect on one of the most densely populated and industrial regions of Turkey whose population accounts about 20 percent of Turkey's total population. In addition to providing shelter, the major objective of this project was to re-establish those humanistic and natural values that had been lost or obscured in respect of the traditional, Turkish life-style and culture, as a result of the rapid urban-isation which took place after the 1950s. In 2000, research was conducted to evaluate the prospective residents' preferences in respect of their future housing and its environment needs. For this purpose, 400 people, who had been living in temporary housing in the area affected by the earthquake, were the target group of an in-depth survey. The main objective of the study was to determine whether the prospective residents' perceptions and evaluations matched the project designed by the ITU's team. It was assumed within the project planning and design that people would prefer the socially, and physically rich environment offered by the project. Based on the research findings, the ideology, philosophy and concepts underlying the “Urban m3 - Respect for Life Project” could be evaluated as an altenative design approach, which provides not only environmental protection and disaster mitigation, but also a high level of socio-cultural satisfaction. Thus, the paper suggests strategies for improved post-disaster (re-)construction.
The Quarter: A Complex of Neighbourhood units in Turkey
Authors: Usta Ayhan , Usta Gülay K.
Published: January 2021

In history, spatial organizations for houses have been changed and improved depending on the natural conditions, well-being of people, utilization of resourses, population density, family structure and urbanization rate. It can be said the spatial organization of housing that they are both in a relationship with culture and they are a total configuration of social, demographical, psycological, human behaviorial and environmental structure.

Any housing settlement in Turkish Islamic tradition is macro and micro scaled organization in which social relation and cultural characteristics of society that are necessary for physical environment and society reflect.

Basic element of urban spatial organization in Turkish Islamic housing pattern is “the quarter”. (Quarter is called as “mahalle” in Turkish culture) The quarter contains functional and semantic characteristics which are common for most Islamic civilization and Turkish Islamic cities.

In this study, what meaning does the quarter have as smallest spatial organization element in Anatolia will be examined. In additon what kind kind of evolutionary process does the quarter face in Turkish settlement.
Environments of Change: An Open Building Approach Towards A Design Solution for an Informal Settlement in Mamelodi, South Africa
Authors: Gottsmann Donovan , Osman Amira
Published: January 2021

Poor living conditions in informal settlements may be attributed mostly, though not exclusively, to the lack of basic services. Informal settlements, which also go by the name of squatter camps, are volatile by nature. Even within relatively fixed settlement boundaries, change in urban fabric continually manifests through altering dwelling configurations. Deemed unstable and unsafe by formal criteria, these environments disclose schizophrenic characteristics: beyond the dirt, grime and smog, exist relatively functional societies capable of survival and self-regulation.

Public and private sector investment within informal settlements is restricted as a result of their illegal status. Inhabitants have no incentive to invest their own resources where they have no formal tenure over the land. Due to a rather backward approach to informality in South Africa, innovation in dealing with these settlements has been limited. Despite the fact that the rhetoric has sometimes changed from eradication to upgrading, little has been done with regards to alternative forms of settlement development that has relevance in terms of improving the lives of informal settlement dwellers.

With rising anger in poverty-stricken areas and on the peripheries of cities, what is needed is improved service delivery through immediate solutions. This article suggests a service delivery core, an architectural catalyst, rooted to the ‘energy’ of the public realm, stimulating growth of infrastructure networks. This catalyst core aims to instigate the amelioration of the surrounding environment.

The concept presented is that of a dynamic service core – universal in principle – while also being contextually-driven by responding to a specific environment and needs of a specific community. A generic architectural solution is thus presented to providing basic services and infrastructure within informal settlements, with focussed consideration for the unique situation of an informal settlement in Mamelodi, Tshwane (Pretoria), South Africa. It is important to realise that there is no final product, but rather an organic architecture that adapts in a process of continuous and progressive change.
A Reading in Critical Regionalism: Analysis of Two Houses By Han Tümertekіn*
Authors: Aycı Hilal , Boyacıoğlu Esin
Published: January 2021

If regionalism is defined as designing responsibly in reaction to a local context, then critical regionalism can be defined as doing so without denying the universally enlightening content of the modernist project. Armed with this definition, this article attempts to analyze two houses by architect Han Tümertekin that are set in a rural context in a very small Aegean village in Turkey. The aim of the paper is to explore the extent to which these two buildings embrace the tenets of critical regionalism and to understand the local relevance as well as international esteem of the buildings.
Urban Aesthetics; Visual Quality Evaluation of “Konya Türbeönü” the Historical Urban Square
Authors: Erdogan Ebru
Published: January 2021

Konya developed as a city with a single centre in historical period, the mound (höyük) known as Alaeddin’s Hill. This is still the central feature of the urban settlement of Konya. The tomb of the great humanist, poet and philosopher, Mevlana Celaleddin-i Rumii, is also here. The most prestigious section of Konya during the Seljuk and Ottoman periods was the Konya Türbeönü, the space in front of his tomb. The historical city centre maintains its liveliness in the area between Alaeddin’s Hill and the tomb of Mevlana. This historical city centre is the most accessible area in the city and functions fully as such while bearing its historical identity.

The transformation of Konya from single-centred city to multi-centred city resulted in considerable changes in the city’s silhouette. The Konya Türbeönü Square was redesigned and presented for use. While defining the effect of outdoor spaces on human life, they are evaluated as places that meet basic physical, social and psychological requirements. Since the planning process of the Konya Türbeönü Square was not participative, it has remained a focal point of intense discussions and debates about its meeting users’ needs have arisen.

This article studies user satisfaction with the design of the Konya Türbeönü Square and investigates the effects of changes on users. The study survey, asked for demographical information about the users, the sensorial effects of the outdoor space, the effects of its landscape and general satisfaction. The questionnaire was administered to 300 people, including 100 architects who are educated in designing, shopkeepers who are interaction with this area everyday and laypersons. Evaluating the questionnaire data revealed the physical landscape quality and the behavioural and functional qualities of the users along with the visual qualities of the historical urban square’s former/older condition. This study aims to show how participative planning can improve future projects.
A Study on Analysis of Housing Settlements: The Case of Senesenevler
Authors: Ozorhon Guliz
Published: January 2021

This study on the knowledge/experience transfer regarding architectural space has two main objectives. The first of these is to develop an in-depth analysis on housing settlements and the second one is to provide pioneering and unique approach of a housing settlement in the 50s in Istanbul to architectural milieu. In the study, first how it is possible to propose such a method will be discussed, and will be followed by a review of the literature on the subject of housing and by which parameters it can be described. After this preliminary research, a systematic approach consisting of two steps (1. Reading, 2. Conceptualization) to analyze the housing settlements will be proposed and this approach will be exemplified by a housing settlement in Istanbul. In short, this article is primarily concentrated on tools required first to understand and then explain a housing settlement.
Pedestrianization and Walkability in a Fast Developing Unesco World Heritage City
Authors: Zainol Rosilawati , Wang Chen , Ali Azlan Shah , Ahmad Faizah , Aripin Abdul Wafey Mohd , Salleh Hafez
Published: January 2021

A walkability friendly environment is crucial in historical towns and cities built with minimal number of motor vehicles. This research aims to assess physical attributes of pedestrianization in Georgetown, Penang, a UNESCO World Heritage Site regarding walkability. A structured interview was conducted among 170 respondents at six different streets to examine citizens' satisfaction on the pedestrian facilities using six walkability features including a) pathway, b) zebra crossing, c) signage, d) personal safety, e) traffic flow and, f) aesthetics & amenities. Relative Importance Index (RII) analysis show that existing pathways do not meet acceptable standards in promoting a walkable environment. Aesthetic and amenities scores the lowest in satisfactory level and zebra crossing scores the highest in unsatisfactory level. The level of walkability in the World Heritage Site in Georgetown, Penang are found inadequate. Provision of physical walking and built heritage features without providing sufficient activities along the streets do not yield high walkability.