bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of Dispersion Image Resolution Acquired Using Multichannel Analysis of Surface Waves with Different Source Energy and Stacking
Authors: Basri K , Talib M K A , Ping B P A , Jumien N L , Zainorabidin A , Lim A J M S , Dan M F M , Talib Z A
Published: June 2020

Active MASW method is a promising method to determine the stiffness characteristics of the subsurface strata. The accumulation energy to obtain high-resolution dispersion image depends largely on the energy generated from the active source. From the results obtained, the influence of different source energy, source plate and number of stacking on the dispersion image resolution were significant. Heavier source weight (e.g.7 kg sledgehammer) produced highamplitude energy band and provides even lower frequencies. However, if lighter source weight (e.g. small steel hammer) was used, it needs to be coupled with rubber plate to increase the low frequency content, thus generate deeper depth of investigation. Finally, the use of rubber plate and stacking increased the resolution of the dispersion image especially at lower frequencies by significantly suppressing the ambient noise.
Finite Element Analysis of Green Concrete Hollow Block (GCH block) System
Authors: Bosro M Z M , Samad A A A , Mohamad N , Goh W I , Tambichik M A
Published: June 2020

This paper presents the finite element analysis (FEA) study of Green Concrete Hollow Block (GCH block) system. The designed system is the new approach for Malaysia construction industry to replacing the traditionally construction system. The blocks are interconnected through tongue and groove besides 20 mm protrusion provided for the self-alignment features. This study utilized explicit dynamics procedures offered in ABAQUS software to analyse the GCH block prism under axial loading. Several input parameters are taken from previous study to complete the analysis process. The simulation is conducted to analyse the structural behaviour in terms of its ultimate load, cracking patterns, deformations and also the stresses distributions. The analysis results show that the Green Concrete Hollow Block (GCH block) system is suitable to replacing the traditionally bonded masonry system.
Behavior of Shear Connector Variations on Strengthened Reinforced Concrete Slabs Using Cold Formed Steel
Authors: Puluhulawa I , Alamsyah
Published: June 2020

The method of execution the installation of strengthened material on building structural elements is sometimes a problem because it requires special expertise and expensive. In addition, structural elements strengthened using mortars or additions concrete have shown a collapse that begins with the release of these strengthening material making it difficult to be composite. This research has been tried alternative strengthened using cold formed steel (CFS) profile that were bonded with Epoxy Sikadur CF-31 and Dynabolt M10 so that the strengthened material becomes composite with the existing slab. The purpose of this slab strengthened was to increase the capacity of reinforced concrete slabs to resist bending loads. Five concrete slab test have been made with dimension 45x145x12 cm with longitudinal reinforcement Ø10-140 mm and transverse reinforcement Ø8-650 mm. The four slabs are strengthened using CFS type C75, 0.75 with spacing of 200 mm. Two slabs use the Sikadur CF-31 Epoxy as glue (SSE) and the other two use Dynabolt M10 as shear connectors (SSD). Furthermore, a flexural test was carried out by given one point load in the middle of spans. The results have shown an increase in the flexural load capacity of SSE and SSD. Moreover, the use of Epoxy Sikadur CF-31 as a glue has increased the stiffness of the strengthened slab while the use of Dynabolt can maximize the ability of CFS to carry bending loads.
Geopolymer Mix in Accordance to Design of Experiment (DOE) Method
Authors: Atan H , Mohd Ali A Z , Khalid N H Abd , Mohamed A
Published: June 2020

This paper presents an experimental study conducted to assess the capability of using DOE method to achieve particular targeted strength for geopolymer concrete. Targeted strength of 30 MPa, 40 MPa and 60 MPa were used in this study. Cube samples with dimension of 100 mm were used for compressive strength test. Similar DOE method calculation as in normal concrete mix were calculated for all the raw material ratios in geopolymer concrete mix. Parameters such as characteristic strength, standard deviation (s), margin (m), target mean strength (fm), free-water/cement ratio (w/c), slump, relative density of aggregate (SSD), concrete density (D), percentage grading of fine aggregate passing 600 μm sieve, and proportion of fine aggregate were determined according to the respective concrete mix design. However, only characteristic strength, fm and w/c varied in each targeted strength mix design while the other parameters were kept constant. In order to yield geopolymer concrete, the used of cement and water in DOE form were fully substituted with the used of fly ash and alkaline activator respectively. Final strength gained from test result for the respective 30 MPa, 40 MPa and 60 MPa were 74.6 MPa, 84.5 MPa and 97.7 MPa. Therefore, it was noted that geopolymer mix yielded higher strength compared to the targeted strength by using the DOE method calculation.
Physicochemical characteristics of PM2.5 particles during high particulate event (HPE) in school area
Authors: Ramli N A , Shith S , Yusof N F F Md , Zarkasi K Z , Suroto A
Published: June 2020

Observations of fine particulate matter (PM2.5) and meteorological parameter (temperature, relative humidity and wind speed) fluctuations during a high particulate event (HPE) in Sekolah Kebangsaan Bayan Lepas, Malaysia have been conducted for three days (48 hrs). Selected sample spot of collected PM2.5 particles with high concentration was chosen to investigate the physicochemical characteristics using Field Emission Scanning Electron Microscope coupled with Energy Dispersive X-ray (FESEM-EDX). The results show that the 24 h average concentration ± standard deviation of PM2.5 (81.87 μg m−3 ± 31.83) exceeded the limit suggested by Malaysia Ambient Air Quality Standard (MAAQS-2020) and United State Environmental Protection Agency (USEPA) which is 35 μg m−3. The diurnal variations of PM2.5 concentration fluctuated significantly during HPE. Results from Pearson correlation shows that relative humidity gives the most significant influence towards PM2.5 concentration (r = 0.410; p < 0.01) followed by wind direction (r = -0.306, p < 0.01), temperature (r = -0.262., p<0.01) and wind speed (r = -0.206; p < 0.01). From a morphological and elemental analysis, it shows that PM2.5 particles collected on a filter consist of two possible sources, natural and anthropogenic sources. The element components found in the natural particles were C, O, Na, Al, Si, S, K and Fe. The major components were C, O, Al, and Si with weight percentages were 18%, 39%, 9%, and 22%. Dominant elements in anthropogenic particles were C (41%) and a significant amount of K (3%) are found which considered as biomass burning soot. Besides that, the particles also consist of O, Na, Al, Si, and Cl. In summary, particles from natural and anthropogenic sources are dominant in the ambient PM2.5 during HPE.
Requirement of Outdoor Water Filtration System
Authors: Mohd Kamil N A F , Abdullah F N , Mizad M
Published: June 2020

Presently, outdoor water filtration (OWF) system becomes one of home appliances that is a must-have for every house in Malaysia. Even though the tap water is a guarantee can be consumed directly, Malaysians still need the appliances. These home appliances become popular nowadays, however the requirement of the OWF is never determined. This study focuses on OWF system which improves quality of water from the plant treatment at point of entry before it gets to consumers. The purpose of this study was to understand qualitatively the requirement of OWF system through awareness of the consumers. In addition, residual chlorine was also measured to determine the performance of the system. Seven houses that have been using OWF were asked on their awareness on the technology used in their system and mostly said they knew the technology used. However, they are less aware on types of filter media and water parameter that are related to quality of effluent water. Based on the measurement of residual chlorine, the percentage removal after the system was in the range of 76% to 96%. This high removal was reduced the chlorine concentration far below the recommended, thus the safety of water effluent is uncertain. This study shows that requirement of using the system can still be disputed and therefore the large number of sample may require for further study to obtain the real need of OWF system in Malaysia.
Composition of particle size at Regency Beach, Port Dickson
Authors: Isha I B , Adib M R M , Daud M E
Published: June 2020

In 2015, the coastline in Negeri Sembilan was recorded to have 10.2 km erosion, which is 17.59% of the total 58 km of coastline in the state. Regency Beach, located in Port Dickson, is one of the areas affected by erosion. This preliminary study was conducted to determine the sediment distribution along the coast of Regency Beach. Nine (9) sampling points were identified starting from the lowest water line up to 40 meters inland, over 800 m along the coast. Sedimentary samples were taken in pore strata and analysed to obtain soil characteristics and particle size classification. According to the USCS classification, the sediment in the study area may be considered as moderate sand. Values of uniformity coefficients, Cu and curvature coefficients, Cc show a uniformly uniform distribution with very low moisture content.
Simulation of Transmission of Drinking Water Sources to Reservoirs: Case Study PDAM Tirta Jati, Cirebon, Indonesia
Authors: Safitri Adam , Wahyudi S. I. , Soedarsono
Published: June 2020

Population dynamics have very important effects on ecosystems, including those related to water availability. The availability of clean water is closely related to the condition of the population in an area. Every human being must drink 8 (eight) glasses of water per day. Plants and animals also need water. So it can be said that water is one source of life. Regional Water Supply Company (PDAM) is a company whose ownership is held by the regional head as the operator of drinking water supply for the community. Companies are encouraged to utilize developing technology to manage their drinking water assets effectively and efficiently so they can improve services to the community. EPANET 2.0 is one tool that is suitable for connecting piping network models. Quantum Geographic Information System (QGIS) is a model simulating hydraulics which parameters can be launched through a processing stage. The master network system model created in QGIS was included in EPANET 2.0 for rasterization. Then enter the required data such as pipe length, height of each node, water flow per tapping, pipe roughness coefficient, and peak hour factor. The results of the analysis in the form of pipe hydraulics, such as pipe speed and pressure from each node are used as a basis for network development plans. The ratio of the total population per family in Sumber District in 2018 is 6 people/head of the family. The population in the administrative area served by PDAM is 22,560 people. Domestic water needs can be calculated based on data on average water usage per month recorded at PDAM Tirta Jati, Cirebon Regency. The number of domestic customers was 2,446 in August 2019 with an average monthly water consumption of 15.02 m3/unit. Based on analysis using Epanet and QGIS, parameter data for pipe flow rates are 0.63 - 1.05 meters/second. While the result for water pressure in the pipe is 140.95 meters at node 274.
Simulation of Catchment Area, Water Storage and Pump Capacity in Polder Drainage System
Authors: Ikhwanudin  , Wahyudi S. I. , Soedarsono
Published: June 2020

Tidal flooding that occurs on the northern coast of Semarang City is caused by high rainfall, sea water level rise, and is exacerbated by land subsidence. Handling of tidal flooding is recommended with a polder system. Tidal flood management is made of several alternative retention ponds located in the Banger region so that water can flow in the new retention pond at the pump into the river so that the water goes to the sea. The purpose of this study is to formulate a correlation between catchment area, retention pool and pump capacity. Rainfall-runoff as well as hydraulic parameters were computed and simulate using SWMM software Version 5.1. Based on the analysis results, it clearly shows that, the flood discharge of 24 m3/s can be overcome by integrated pond structure with pump configuration. Alternative 1 retention pool 1 with a storage volume of 15,000 m3, Alternative 2 combined ponds 1 and 2 with a storage volume of 11,400 m3, Alternative 3 combined 3 ponds 1, 2 and 3, storage volume of 14,200 m3, alternative 4, is a combination of the three retention ponds above, with a storage volume of 64,300 m3. The water level in the pond is maintained not to overflow when pumping is carried out with the addition of the pool area, it will further reduce the capacity of the pump that is turned on with certain configurations on the pump operation schedule.
Rapid Buildings Growth and Environmental Impacts in Kano Nigeria
Authors: Abdullahi Hashim , A/L Sinniah Gobi Krishna , Siong Ho Chin , Mohd Azman Nur Shaheera
Published: June 2020

All Rapid building growth is one of the top environmental challenge especially in developing nations. Kano metropolis Nigeria is rapidly expanding that calls for in-depth study. The aim of the study is to assess the environmental impacts of buildings growth in Kano metropolis Nigeria towards sustainability. Carbon monoxides CO was sensed with the aid of device Gas Sensor by Crown Cone and water sampled was taken from the existing ponds and analysed in the laboratory considering physiochemical properties of suspended particles, salinity, colour and total hardness. Geographical Information System (GIS) was used for the location maps preparation. Both indoor and outdoor carbon monoxides was sensed and recorded in selected local governments. The Outdoor carbon monoxide records of the sampled local governments areas of Kano Metropolis shows that Tarauni and Kumbotso recorded exactly 012 ppm as the highest records and Tarauni local government area maintain the highest indoor carbon monoxide emission also. Dala and Fagge local governments’ areas depicted 011 ppm as the second highest records with regards to outdoor carbon monoxides emission but Dala, Gwale and Fagge local governments portrayed proportionately equal amount of indoor carbon monoxides emission of 008Ppm. In addition, the results of water analysis reveals that suspended solid contents and the salinity level of Shema Pond being more contaminated with (248 mg/l and 25 mg/l) against Hauran Wanka Pond with (61 mg/l and 20 mg/l). Colour and t. hardness of Hauran Wanka Pond indicates 501 ml/g and 0.16 mg/l) which is higher than Shema Pond with (290 mg/l and 0 mg/l). It is strongly recommended to preserve and conserve both water and air resources in the metropolis for suitability.
Temporal and Spatial Analysis of the Occupational Noise at Rice Mill in Kedah
Authors: Mansor A Abu , Abdullah S , Ahmad Nawawi M A , Ahmed A N , Mohd Napi N N L , Ismail M
Published: June 2020

Noise or unwanted sound, is considered as occupational pollution, especially one that is loud or unpleasant or that causes disturbance to human and surroundings. Occupational noise is a noise emitted from various industries that effect the workers’ safety and health. A prolonged exposure towards noise can bring negative effects to the receptor, resulting in noise induce hearing loss (NIHL) diseases. The state of Kedah is known as the rice bowl of Malaysia, producing more than half of the country’s home grown rice supply. Majority of the rice mill is situated in Kedah where the major occupational hazard for the workers is noise during the operation of various machines to convert paddy to rice. The aim of this study is to assess the noise risk assessment in the rice mill. The noise level was measured during working hours of 0900hrs – 1800hrs for three consecutive days using sound level meter. The evaluated daily noise level Leq
, did not exceeded the limit enacted by the Occupational Safety and Health (Noise Exposure) Regulation, 2019 but there were occasions the reading surpassed the limit, ranging from 86.5 dBA to 90.3 dBA. Measurement of noise exposure at 1-meter distance for machineries located in the rice mill was also conducted and the most critical location in the rice mill is the Rice Huller machine.. Noise sources from the machinery shows strong negative correlation with noise level (r = -0.97, p<0.05) (Air Blower), (r = -0.94, p<0.05) (Rice sieving), (r = -0.98, p<0.05) (Air Pump), (r = -0.95, p<0.05) (Rice Huller) and (r = -0.95, p<0.05) (Rice Polisher), correspondingly. The findings from this study is important for the company management team as abatement measures for the employees in providing a more conducive working environment and indirectly increases the productivity of the company.
Women’s Accessibility to Properly Fitting Personal Protective Clothing and Equipment in the Australian Construction Industry
Authors: Oo B L , Lim T H B
Published: June 2020

With a growing diverse workforce in the construction industry, properly fitting personal protective clothing and equipment (PPE) is an essential component of safety for any worker. As a minority group in the industry, there is much anecdotal evidence of women’s difficulties in accessing properly fitting PPE. Based on a large-scale online survey, this study explores the difficulties experienced by women in the Australian construction industry in accessing properly fitting PPE. While PPE for women is available on the market, the results show that access to properly fitting PPE is still a major issue for women workforces in the industry. The problems they are facing include: the need to make alterations or adjustments to ill-fitting PPE, the lack of adequate training or proper use of PPE in their job tasks, and ill-fitting PPE has hampered their work in some way. The male-dominated culture of the construction industry has been identified as the top key reason for their lack of access to properly fitting PPE. These thus call for the industry stakeholders to address women’s PPE concerns, and one key step would be to promote awareness of women’s PPE needs within the construction industry.
Challenges of Implementing Green Procurement in Public Construction Projects in Malaysia
Authors: Tawfik Alqadami Ahmed , Abdullah Zawawi Noor Amila Wan , Rahmawati Yani , Alaloul Wesam , Alshalif A Faisal
Published: June 2020

Although the concept of green procurement is increasingly debated as an environmental policy instrument that considers the impact of procurement on the sustainability of project development, however, the concept in Malaysia is still in its infancy and facing various barriers and challenges to make a paradigm shift towards a greener approach. Therefore, this paper tends to determine the challenges that hinder green procurement implementation in building and infrastructure projects. This could pave the road to establish a transformation plan that could gradually overcome the current challenges in order to reach the desired level. The study is based on a survey conducted in the Malaysian construction industry at which 380 corporations were surveyed to determine their perspective on 28 pre-determined challenges and their degree of significance. A number of 142 were valid responses. Results revealed that there is an excellent consistency in the significance of the identified challenges. Reducing the use of natural resources and related waste, minimizing the high cost of eco- products, integrating quality environmental management into planning and operation and achieving the value of money are among the important challenges. Achieving financial, environmental and operational impact of green procurement performance are also significant challenges.
Sustainable Cities, Transportation and Warehousing GDP
Authors: Ikhsan Setiawan Muhammad , Sukoco Agus , Harmanto Dani , Halim Paisal , Mursidi Andi , Ting I-Hsien
Published: June 2020

The development of the airport city, integrated commercial property, and the land, produces non-aeronautical income from tourists, business people, and cargo. The research uses secondary data archives that contain past (historical) events to find out several factors that affect transportation and warehousing GDP. Other data provided in the study is panel data, which is data of several airport locations (cross-section). Data analysis is then carried out by using quantitative methods. Meanwhile, sampling is done by purposive sampling that was based on individual or researcher’ considerations, which often referred to as sampling considerations. Initially, the population is 299 airports that are managed by PT. Angkasa Pura I and PT. Angkasa Pura II, and UPT Air Transportation. It is then reduced to 172 airports throughout Indonesia, which later is filtered further to only 151 airports. Results of the multiple linear regression analysis show that factors that affect Transportation and Warehousing GDP are the plane arrived, the plane departed and passengers depart. ARX estimation and ARX Validation Transportation and Warehousing GDP, that produces a fit of 51.08% and a fit validation of 51.45%. Of the 90 data used for estimation, 46 data, or 51.08% of ARX, have similarities with existing data. The value is quite good because the fitness produced is > 50% that affect Transportation and Warehousing GDP are the plane arrived, the plane departed, passenger departing, departing passengers, unloading baggage, loading baggage, unloading cargo and loading cargo. All are influential on Transportation and Warehousing GDP
Adsorption effect of oxygen on ZnO Nanowires (100 nm) leading towards pronounced edge effects and voltage enhancement
Authors: Ahmad Mansoor , Ahmad M K , Nafarizal N , Soon C F , Suriani A B , Mohamed A , Mamat M H
Published: June 2020

Here, we report high output piezoelectric voltage generation from oxidized ZnO nanowires (100 nm). Periodic high output voltage peaks were observed during series of oxygen exposure experiments. Gradual rise in piezoelectric potential from oxidized ZnO nanowires is being evidenced for the very first time. Sharp voltage peaks 464 mV, 803 mV, 1.354 V, 1.795 V and 2.44 V are observed for an exposure of oxygen for 1 h, 2 h, 3 h, 4 h and 5 h respectively in a sealed chamber at 50 ppm. It has been observed maximum output value has been saturated after 5 h of O exposure. Enhanced piezoelectric potential appearing at output stages is due to the adsorption of oxygen molecules on long ZnO nanowires, giving rise to ‘Edge Effects’ and consequently reducing reverse leakage current through nanowires and enhancing output voltage. SEM images revealed the surface morphology ZnO nanowires, diameter range was found around 100 nm. XRD pattern verified vertical growth orientation of ZnO nanowires on ITO (indium Tin oxide) coated PET (poly ethylene terephthalate) substrates. Minute external force ∼50 nN is used to produce piezoelectric potential within nanowires.
Can health behaviours prolong survival and compress the period of survival with the disability? A population-based cohort study
Authors: Wu Wei , Xu Weili , Englund Simon , Shang Ying , Pan Kuan-Yu , Rizzuto Debora
Published: June 2020

Background

It remains unclear whether and to what extent health behaviours may prolong survival and compress the period of survival with disability.

Objective

To identify modifiable health behaviours that are associated with later disability onset and longer disability-free survival.

Design

This population-based cohort study used data from the Swedish National Study on Ageing and Care in Kungsholmen (SNAC-K) ranging between 2001 and 2016.

Setting and subjects

A total of 3,041 disability-free adults aged ≥60 years were followed up to 15 years.

Methods

Data on health behaviours were collected at baseline. Information on limitations in activities of daily living was obtained at baseline and during the follow-up. Laplace regression was used to model the median age at death and disability occurrence as a function of health behaviours.

Results

Never smoking, moderate alcohol drinking, rich social network and high leisure activity were individually related to longer survival by 1–3 years. Participants with high leisure activity lived 1.6 years (95% CI: 0.9–2.3) more without a disability. After combining lifestyle factors, social network, and leisure activities into a 4-level ‘health behaviour profile’, people with the healthiest behaviour profile lived 2.8 years (95% CI: 1.3–4.2) longer, had disability 3.5 years (95% CI: 1.7–5.3) later and lived 0.7 years (95% CI, 0.4–1.1) more without a disability compared to those with the least healthy behaviours profile.

Conclusions

These findings suggest that health behaviours could prolong the lifespan, and leisure activities may further compress years lived with disability among older adults.
Beyond Diversity: Focusing on and Enhancing Inclusion in the Society for Epidemiologic Research
Authors: Moore Kristin J , Xiong Serena , Bhattacharya Manami , Bustamante Gabriela , Calvert Collin
Published: June 2020

Increasing diversity and inclusion among organizational membership has become a focus for many professional societies, including the Society for Epidemiologic Research (SER). In this issue of the Journal, DeVilbiss et al. (Am J Epidemiol. 2020:189(10):998–1010) assessed dimensions of diversity and inclusion within SER to provide baseline data for future evaluations of Society initiatives. In our response, we note that diversity in SER appears strong but there is lag with regard to inclusion. We also highlight some of the major weaknesses of this study that hinder efforts to accurately evaluate inclusion within SER. There is a need to more concretely define inclusion and think broadly about how measures of inclusion should be operationalized in future surveys. Additional limitations of the study include its limited generalizability to the wider SER membership and the lack of questions about barriers to inclusion in SER activities. We conclude with recommendations for SER and other professional societies based on prior literature evaluating successful diversity and inclusion efforts. We also propose a conceptual model to assist with operationalizing and directing future analyses of inclusion measures. It is essential that SER move beyond efforts around diversity to focus on measuring and enhancing inclusion.
Race and Relevance: Arthur Garfield Hays and the Integration of the American Bar Association, 1938-1943
Authors: Hamm Richard F
Published: June 2020

This article explores the role of Arthur Garfield Hays and mostly Jewish lawyers in dismantling the American Bar Association’s prohibition of African Americans becoming members. By publicly resigning from the organization and encouraging others to do so over the ABA’s treatment of African-American applicant Francis Rivers, these lawyers made the color bar a public issue in the press. While earlier efforts in the late 1930s had failed, World War II contributed to the success of the activists’ campaign in the early 1940s, as the struggle against Nazi racism had begun to undercut American racial practices. In August 1943 the ABA changed its procedures governing admission that had previously functioned to exclude African-Americans. Other legal professional organizations soon followed its example. Thus the legal profession refashioned itself into part of the liberal order emerging in the wake of World War II.
Alcohol Consumption among Samoan Adults in 2010: Patterns, Correlates and Health Implications
Authors: Jiang Joy J , Reupena Sefuiva M , Naseri Take , Swift Robert M , McGeary John E , McGarvey Stephen T
Published: June 2020

Aims

We aim to describe alcohol consumption and related problems from a nationwide survey in 2010 in Samoa in association with sociodemographic variables as part of an intervention development.

Methods

The sample consisted of 3463 adults, 25–65 years of age. Participants self-reported alcohol consumption in the previous 12 months, patterns of drinking and alcohol-related psychosocial problems. Data about age, census region of residence, highest attained education level, employment, marital status, household assets score and current smoking status were gathered.

Results

More than one-third of men, 36.1%, and 4.1% of women consumed alcohol in the past year. There were greater proportions of alcohol users among younger adults, <45 years, in both men and women. Among men, being unemployed and residing outside of rural Savai’i and smoking cigarettes were associated with current alcohol use. Among women, tertiary education and cigarette smoking were strongly associated with alcohol use. Among alcohol consumers, almost 75% of both men and women reported being drunk more than once in the prior month, and 58% of men and 81% of women drank heavily, consuming >4 drinks for women and >5 drinks for men at least once per episode in the prior week. More men than women, 51% versus 26%, felt that alcohol consumption had interfered with their daily life.

Conclusion

Our analyses identified correlates of alcohol consumption and associated problems that can help guide the development of targeted interventions for different sex and age groups to mitigate the social and physiological harms of alcohol misuse.
Wildfires and mass effects of dispersal disrupt the local uniformity of type I songs of Hermit Warblers in California
Authors: Furnas Brett J , Landers Russ H , Bowie Rauri C K
Published: June 2020

Hermit Warblers (Setophaga occidentalis) sing a formulaic, type I song to attract mates, in contrast to a repertoire of more complex, type II songs to defend territories. A single, dominant type I song, or a low diversity of type I songs, often occur within a geographic area. We provide the first comprehensive description of Hermit Warbler type I song variants throughout California, USA. We recorded type I songs from 1,588 males across 101 study sites in the state from April through July 2009–2014. Using those locations and a pre-existing range map of the species, we created a maximum entropy-based breeding habitat suitability map and classified the songs into 35 variants using a typological rubric. We validated consistent classification of songs for 87.5% of the birds. We then modeled the effects of recent fire history at the local scale (10 yr, 315 km2), the amount of breeding habitat at the regional scale (8,000 km2), and the distance between territories to examine factors involved in song sameness at the local scale. We found that the probability of different birds singing the same form declined with the amount of local fire, regional habitat, and distance, and that these findings were robust to uncertainty in our song classification rubric. Using a longitudinal analysis including additional data from 10 study areas revisited in 2019, we showed that song structure within forms had drifted since our initial visits 5–10 yr earlier, and that the evenness (e.g., Simpson’s measure) of song forms increased at locations that had been burned by wildfire between visits. Taken together, the results suggest that wildfires and the mass effects of dispersal of birds singing rival song forms disrupt the uniformity of type I songs locally. The results demonstrate how species traits, such as birdsong, can be used to disentangle the ecological processes that regulate observed patterns in biodiversity. Further investigation is recommended to determine whether song pattern dynamics reflect underlying genetic differences and habitat specializations among subpopulations.
Exogenous sex steroids regulate genital epithelial barrier function in female rhesus macaques
Authors: Quispe Calla Nirk E , Vicetti Miguel Rodolfo D , Fritts Linda , Miller Christopher J , Aceves Kristen M , Cherpes Thomas L
Published: June 2020

There is concern that using depot-medroxyprogesterone acetate (DMPA) for pregnancy prevention heightens HIV susceptibility. While no clinical data establishes causal link between HIV acquisition and use of this injectable progestin, prior work from our laboratory showed that DMPA comparably lowers genital levels of the cell-cell adhesion molecule desmoglein-1 (DSG1) and weakens genital epithelial barrier function in female mice and women. We likewise saw DMPA increase mouse susceptibility to multiple genital pathogens including HIV. Herein, we sought to confirm and extend these findings by comparing genital epithelial barrier function in untreated rhesus macaques (RM) vs. RM treated with DMPA or DMPA and estrogen (E). Compared to controls, genital tissue from RM with pharmacologically relevant serum levels of medroxyprogesterone acetate displayed significantly lower DSG1 levels and greater permeability to low molecular mass molecules. Conversely, DMPA-mediated effects on genital epithelial integrity and function were obviated in RM administered DMPA and E. These data corroborate the diminished genital epithelial barrier function observed in women initiating DMPA and identify RM as a useful preclinical model for defining effects of exogenous sex steroids on genital pathogen susceptibility. As treatment with E averted DMPA-mediated loss of genital epithelial barrier function, our results also imply that contraceptives releasing progestin and E may be less likely to promote transmission of HIV and other sexually transmitted pathogens than progestin-only compounds.
Morphological evolution and molecular phylogenetics of the Merostachys clade (Poaceae: Bambusoideae: Bambuseae: Arthrostylidiinae) based on multi-locus plastid sequences
Authors: Vinícius-Silva Ronaldo , Clark Lynn G , Fregonezi Jéferson Nunes , Santos-Gonçalves Ana Paula
Published: June 2020

Merostachys is a Neotropical woody bamboo genus that occurs in the understory and along forest borders. Our taxonomic studies of its species and morphological analyses have allowed us to recognize morphological groups in the genus. Previous molecular analyses, which included relatively few species, supported Merostachys as monophyletic and sister to Actinocladum or Athroostachys. We here provide a phylogenetic estimation for Merostachys based on a broader taxon sampling and seven plastid markers (one coding: ndhF 3′ end; four intergenic spacers: rps16-trnQ, trnC-rpoB, trnD-trnT and trnT-trnL; and two introns: rpl16 and rps16). We aimed to test the monophyly of the genus, to verify its relationship with other genera of Arthrostylidiinae, mainly Athroostachys and Actinocladum, and to test whether the previously identified morphological groups were congruent with the molecular data. The monophyly of the genus was confirmed, as was its sister relationship with Athroostachys, although alternate hypothesis testing could not reject a sister relationship with Actinocladum. Two well-supported clades in Merostachys were recovered, one of which encompasses a polytomy. These clades did not exhibit consistent morphological synapomorphies and were not congruent with the morphological groups; however, floret surface (shiny vs. dull) was correlated with the two clades. The lack of resolution in Merostachys, as exemplified by the polytomy, can be attributed mainly to incomplete lineage sorting, suggesting a recent radiation in this group.
Timing is everything: tau imaging across stages of Alzheimer’s disease
Authors: Forsberg Morén Anton , Varrone Andrea
Published: June 2020

This scientific commentary refers to ‘18F-MK-6240 PET for early and late detection of neurofibrillary tangles’, by Pascoal et al. (doi:10.1093/brain/awaa180).
Hospital Costs of Injection Drug Use in Florida
Authors: Coye Austin E , Bornstein Kasha J , Bartholomew Tyler S , Li Hua , Wong Stanley , Janjua Naveed Z , Tookes Hansel E , St Onge Joan E
Published: June 2020

People who inject drugs (PWID) experience significant injection-related infections (IRIs) at significant healthcare system cost. This study used and validated an algorithm based on the International Classification of Diseases, Tenth Revision, to estimate hospitalized PWID populations, assess the total statewide morbidity for IRIs among PWID, and calculate associated costs of care.
Measles, Mumps, Rubella, and Varicella Zoster Virus Serology and Infections in Solid Organ Transplant Recipients During the First Year Posttransplantation
Authors: Rezahosseini Omid , Sørensen Søren Schwartz , Perch Michael , Ekenberg Christina , Møller Dina Leth , Knudsen Andreas Dehlbæk , Kirkby Nikolai , Lundgren Jens , Lodding Isabelle P , Wareham Neval Ete , Gustafsson Finn , Rasmussen Allan , Nielsen Susanne Dam
Published: June 2020

Background

Mumps, measles, rubella, and varicella zoster (MMRV) viruses may cause severe infections in seronegative adult solid organ transplant (SOT) recipients, but can be prevented by vaccination. We aimed to determine MMRV serostatus in adult SOT recipients before and 1 year after transplantation as well as evidence of MMRV infections in a large, prospective cohort of SOT recipients.

Methods

This was a prospective study of 1182 adult SOT recipients included in the Management of Posttransplant Infections in Collaborating Hospitals (MATCH) cohort from 2011 to 2017 with a 1-year follow-up. Systematic monitoring of MMRV serology was performed prior to transplantation and 1 year posttransplantation. Polymerase chain reaction (PCR) was used to confirm viral replication in SOT recipients presenting with clinical evidence of infection.

Results

Among 1182 adult SOT recipients, 28 (2.4%), 77 (6.5%), 65 (5.5%), and 22 (1.9%) were seronegative for measles, mumps, rubella, and varicella zoster virus (VZV), respectively, and 165 (14%) were seronegative for at least 1 of the MMRV viruses. One year posttransplantation, 29 of 823 (3.5%) of seropositive SOT recipients had seroreverted, and 63 of 111 (57%) of seronegative SOT recipients seroconverted for at least 1 MMRV virus. No evidence of measles, mumps, or rubella infection was found, but 8 (0.7%) SOT recipients developed symptoms and had a positive VZV PCR.

Conclusions

A large proportion of SOT recipients were seronegative for at least 1 of the MMRV viruses. MMRV infections in SOT recipients may disseminate and become fatal, and although only a few cases of VZV infection were detected, results from this study suggest increase attention toward vaccination of patients waiting for SOT.
Swiss needle cast tolerance in British Columbia’s coastal Douglas-fir breeding population
Authors: Montwé David , Elder Bryan , Socha Peter , Wyatt Jessica , Noshad David , Feau Nicolas , Hamelin Richard , Stoehr Michael , Ehlting Jürgen
Published: June 2020

Substantial growth losses in Douglas-fir can be the result of Swiss needle cast, a foliar disease caused by the fungus Nothophaeocryptopus gaeumannii. Although the disease is native to western North America, it is expected to become increasingly problematic in regions where climates become warmer in winter and wetter in spring, such as in coastal British Columbia (BC), Canada. Previous research suggests that tolerance to this disease is under partial genetic control. We therefore aim to screen for tolerance and resistance to the disease in the tree breeding population of coastal Douglas-fir (Pseudotsuga menziesii var. menziesii) in BC. We evaluated if early screening for resistance or tolerance to this disease is possible. We worked with 32 families grown for 18-years on two full-sibling genetic field trial sites representing different climates. We assessed >900 trees for disease signs and symptoms from 2017 to 2019. Needle retention was assessed in the field. In the laboratory, the proportion of stomata occluded with pseudothecia was measured, deoxyribonucleic acid (DNA) was extracted, and the proportion of fungal DNA in the needles was assessed using quantitative polymerase chain reaction. Strong differences were observed among families for needle retention, stomatal occlusion and fungal load. The milder and wetter site closer to the coast was generally more severely affected. Families showed rank changes between the two sites for all response variables. Higher needle retention was correlated with increased tree volume. No correlation was found between the proportion of stomata occluded with pseudothecia, fungal DNA load and needle retention. These results indicate that a more complex pathology is involved in causing needle loss. We conclude that screening for Swiss needle cast tolerance in the coastal BC Douglas-fir breeding population is possible if needle retention can be assessed and that area-specific deployment strategies may be needed given family rank changes in different environments.
Physics-based simulation of sequences with multiple main shocks in Central Italy
Authors: Console Rodolfo , Murru Maura , Vannoli Paola , Carluccio Roberto , Taroni Matteo , Falcone Giuseppe
Published: June 2020

The application of a physics-based earthquake simulator to Central Italy allowed the compilation of a synthetic seismic catalogue spanning 100 000 yr, containing more than 300 000 M ≥ 4.0 simulated earthquakes, without the limitations that real catalogues suffer in terms of completeness, homogeneity and time duration. The seismogenic model upon which we applied the simulator code was derived from version 3.2.1 of the Database of Individual Seismogenic Sources (DISS; http://diss.rm.ingv.it/diss/), selecting, and modifying where appropriate, all the fault systems that are recognized in the portion of Central Italy considered in this study, with a total of 54 faults. Besides tectonic stress loading and static stress transfer as in the previous versions, the physical model on which the latest version of our simulation algorithm is based also includes the Rate and State constitutive law that helps to reproduce Omori's law. One further improvement in our code was also the introduction of trapezoidal-shaped faults that perform better than known faults. The resulting synthetic seismic catalogue exhibits typical magnitude, space and time features which are comparable to those in real observations. These features include the total seismic moment rate, the earthquake magnitude distribution, and the short- and medium-term earthquake clustering. A typical aspect of the observed seismicity in Central Italy, as well as across the whole Italian landmass and elsewhere, is the occurrence of earthquake sequences characterized by multiple main shocks of similar magnitude. These sequences are different from the usual earthquake clusters and aftershock sequences, since they have at least two main shocks of similar magnitude. Therefore, special attention was devoted to verifying whether the simulated catalogue includes this notable aspect. For this purpose, we developed a computer code especially for this work to count the number of multiple events contained in a seismic catalogue under a quantitative definition. We found that the last version of the simulator code produces a slightly larger number of multiple events than the previous versions, but not as large as in the real catalogue. A possible reason for this drawback is the lack of components such as pore-pressure changes due to fluid-diffusion in the adopted physical model.
Data- and model-domain up/down wave separation for reverse-time migration with free-surface multiples
Authors: Guo Peng , Guan Huimin , McMechan George A
Published: June 2020

Seismic data recorded using a marine acquisition geometry contain both upgoing reflections from subsurface structures and downgoing ghost waves reflected back from the free surface. In addition to the ambiguity of propagation directions in the data, using the two-way wave equation for wavefield extrapolation of seismic imaging generates backscattered/turned waves when there are strong velocity contrasts/gradients in the model, which further increases the wavefield complexity. For reverse-time migration (RTM) of free-surface multiples, apart from unwanted crosstalk between inconsistent orders of reflections, image artefacts can also be formed along with the true reflector images from the overlapping of up/downgoing waves in the data and in the extrapolated wavefield. We present a wave-equation-based, hybrid (data- and model-domain) wave separation workflow, with vector seismic data containing pressure- and vertical-component particle velocity from dual-sensor seismic acquisition, for removing image artefacts produced by the mixture of up/downgoing waves. For imaging with free-surface multiples, the wavefield extrapolated from downgoing ghost events (reflected from the free surface) in the recorded data act as an effective source wavefield for one-order-higher free-surface multiples. Therefore, only the downgoing waves in the data should be used as the source wavefield for RTM with multiples; the recorded upgoing waves in the seismograms will be used for extrapolation of the time-reversed receiver wavefield. We use finite-difference (FD) injection for up/down separation in the data domain, to extrapolate the down- and upgoing waves of the common-source gathers for source and receiver wavefield propagation, respectively. The model-domain separation decomposes the extrapolated wavefield into upgoing (backscattered) and downgoing (transmitted) components at each subsurface grid location, to remove false images produced by cross-correlating backscattered waves along unphysical paths. We combine FD injection with the model-domain wavefield separation, for separating the wavefield into up- and downgoing components for the recorded data and for the extrapolated wavefields. Numerical examples using a simple model, and the Sigsbee 2B model, demonstrate that the hybrid up/down separation approach can effectively produce seismic images of free-surface multiples with better resolution and fewer artefacts.
Longitudinal increases in somatic mosaicism of the expanded CTG repeat in myotonic dystrophy type 1 are associated with variation in age-at-onset
Authors: Morales Fernando , Vásquez Melissa , Corrales Eyleen , Vindas-Smith Rebeca , Santamaría-Ulloa Carolina , Zhang Baili , Sirito Mario , Estecio Marcos R , Krahe Ralf , Monckton Darren G
Published: June 2020

In myotonic dystrophy type 1 (DM1), somatic mosaicism of the (CTG)n repeat expansion is age-dependent, tissue-specific and expansion-biased. These features contribute toward variation in disease severity and confound genotype-to-phenotype analyses. To investigate how the (CTG)n repeat expansion changes over time, we collected three longitudinal blood DNA samples separated by 8–15 years and used small pool and single-molecule PCR in 43 DM1 patients. We used the lower boundary of the allele length distribution as the best estimate for the inherited progenitor allele length (ePAL), which is itself the best predictor of disease severity. Although in most patients the lower boundary of the allele length distribution was conserved over time, in many this estimate also increased with age, suggesting samples for research studies and clinical trials should be obtained as early as possible. As expected, the modal allele length increased over time, driven primarily by ePAL, age-at-sampling and the time interval. As expected, small expansions <100 repeats did not expand as rapidly as larger alleles. However, the rate of expansion of very large alleles was not obviously proportionally higher. This may, at least in part, be a result of the allele length-dependent increase in large contractions that we also observed. We also determined that individual-specific variation in the increase of modal allele length over time not accounted for by ePAL, age-at-sampling and time was inversely associated with individual-specific variation in age-at-onset not accounted for by ePAL, further highlighting somatic expansion as a therapeutic target in DM1.