bluuebunny/crossref_metadata_2025 huggingface dataset:
Physical and chemical characteristics in peat lands of Aceh Jaya District, Indonesia
Authors: Arabia T , Basri H , Manfarizah  , Zainabun  , Mukhtaruddin
Published: June 2020

This study aims to determine the physical and chemical characteristics of the peat lands (Histosols) in Aceh Jaya District using descriptive method. The results showed that some physical characteristics such as: water saturation in drilling-M1 (fibric soil materials) was 786.06% higher than drilling-M2 (hemic soil materials) and drilling-M3 (sapric soil materials) were 568.01% and 549.97%, respectively. Bulk density (BD) of drilling-M1, drilling-M2 and drilling-M3 are very low (0.08 - 0.12 g cm−3). Porosity in drilling-M1, drilling-M2 and drilling- M3 are classified as very porous at 95.00%, 93.00% and 90.54%. Some chemical characteristics show as follows: pH in drilling-M1, drilling-M2, and drilling-M3 categorized acid (4.52 - 5.16). Organic-C in drilling-M1, drilling-M2, and drilling-M3 ranges of 20.75 - 55.62% (very high). Exchangeable bases for calcium (3.6 - 23.9 cmol.kg−1), Mg (0.6 - 18.1 cmol.kg−1), and K (0.18 - 1.22 cmol.kg−1) are classified as low - very high. Exchangeable acidity for H (1.2 - 6.1 cmol.kg−1) higher than Al measured only in the drilling of M3 layers of Oa3 (2.3 cmol.kg−1). The CEC in drilling-M1, drilling-M2 and drilling-M3 ranges from 35.28 - 204.48 cmol.kg−1 (high - very high). Bases saturation (BS) ranges from very low - high (11.73 - 73.27%). Soil EC ranges 0.48 - 0.92 dS cm−1 (very low).
The Effect of Straw and Purun Tikus (Eleocharis dulcis) Compost to Rice Physiological Traits, Iron Toxicity and Grain Yield on Acid Sulfate Soils
Authors: Khairullah Izhar , Indradewa Didik , Maas Azwar , Yudono Prapto
Published: June 2020

The experiment was aimed to determine the effect straw and Eleocharis dulcis compost on physiological traits and grain yield of rice grown in acid sulfate. The experiment was conducted in 2010 WS in greenhouse of ISARI, Banjarbaru. The soils was sampled from rice fields of acid sulfate soil. The experiment was employed Factorial CRD, in which first factor was three varieties and second factor were six rates straw and E. dulcis compost. Variables observated were physiological traits (root length, stomatal density, transpiration rate, total chlorophyll content, polyphenol oxidase and peroxidase activity), Fe toxicity symptoms and grain yield. The result showed that application of 5.0 t ha−1 straw and 5.0 t ha−1
E. dulcis compost resulted in the best physiological traits of rice plants, decreased Fe toxicity, but led to increase in grain yield. Inpara 1 was more tolerant to iron toxicity, better physiological traits, lower Fe toxicity symptoms, and higher grain yield compared to Inpara 2. On the other hand, IR64 was susceptible to iron toxicity and the lowest observed. Results of the experiment demonstrate that increasing rate of applied E. dulcis compost up to 5 t ha−1 may increase physiologal traits and grain yield and decrease Fe toxicity symptoms.
Vegetation and Fauna Diversity of High Conservation Value (HCV) Swamp Areas in Oil Palm Plantation
Authors: Kissinger  , Pitri RMN , Violet
Published: June 2020

The designation of an area as a “high conservation value” (HCV) is a form of concern for environmental management. The palm oil company is one of the business units that has responsibility for the existence of HCVs in its area. This study aims to characterize and analyze the components of vegetation and fauna in HCV in swamp areas in oil palm plantations. The research object is in the form of vegetation and wild animals found in HCV swamp areas. The equipment used is: a set of survey equipment, tally sheets, documentation equipment, equipment for data analysis. Vegetation data collection is done using line transect system. Data collected were the number of individuals and the number of species. Fauna data collection is done by exploring and adjusting to vegetation data plots. Data collected were the number of species found in each plot. Vegetation and fauna data were analyzed by using tabulation matrix. Specifically for vegetation species and aves, the data were analyzed using the Shannon-Wiener Diversity Index (H’). There are 8 types of vegetation in the HCV area. The most dominant species found at this location at all levels of growth (seedlings, saplings, poles and trees) is the Melaleuca cajuputi species. The dominant tree species was Melaleuca cajuputi. The important value index of M.cajuputi > 90%. The H’ value for all vegetation levels are classified in the low category. The H’ values of trees, poles, saplings and seedling are 0.84, 0.41, 0.49, 0.46, respectively. There are 16 species of undergrowth which are dominated by plants associated with water. There were 21 species of birds at the study site, 4 of which were protected by government regulation PP No.7 / 1999. There are 21 species of birds with a value of H’=2.5. There are 8 species of mammals (including primates), 6 species of reptiles and 3 species of amphibians. The existence of HCV is very important in contributing to the diversity of homogeneous areas of oil palm plantations. Protecting HCV swamp areas in oil palm plantations are very important for the availability of a conducive animal habitat.
Partnership in Weather Observation using the Crowdsourcing Method
Authors: Radjab A F , Akib H , Rifdan  , Jasruddin
Published: June 2020

Proper weather observation is definitely required to obtain the right and accurate weather information. Currently the weather observation in Indonesia is managed by various parties and coordinated by the Meteorology, Climatology and Geophysics Agency (BMKG). BMKG manage weather observation networks that distributed nationwide. Unfortunately, in terms of quantity and distribution, the current weather observation network is not ideal yet. Increasing the density of the weather observation network is undoubtly needed, therefore BMKG needs to develop a partnership with all parties including general public. This study attempts to identify level of participation of general public and find the ideal partnership model for weather observation in Indonesia. Three partnership variables, namely motivation, consistency and sustainability, examined in this study. As a result of the data analysis it was found that the level of participation of general public is very high especially in the participant group that threat with guidance. And it was also found that the crowdsourcing method can be implemented as an ideal partnership model between BMKG and general public in the field of weather observation.
Increases in Greenhouse Gases Following the Use of Peatlands for Agricultural Areas
Authors: Saidy Akhmad R. , Razie Fakhrur , Aidawati Noor , Hidayat Taufik
Published: June 2020

Peatlands with very high C contents are generally considered a source of greenhouse gas (GHG) emissions. This research aimed to quantify the changes in peatland characteristics and GHG emission from the conversion of peatlands to agricultural areas. Height of water table, pH, electrical conductivity (EC), redox potential (Eh), organic carbon (OC), hot water-soluble C, total-N, the concentrations of NH4
+, and NO3
−, soluble-Al, soluble- Fe, and the emission of CH4, CO2 and N2O were quantified before and after land clearing of peats for agriculture. Results of study showed that pH, EC, OC contents, hot water-soluble-C, and total-N did not change after peatland clearing for agriculture. On the other hand, the concentrations of NH4
+, NO3
−, soluble-Al, soluble-Fe, redox potential and height of water table increased significantly after the peatland land clearing. Methane emissions from peatlands before peatland clearing were in the range of 0.13-0.22 mg C m−2 h−1 increased significantly to 0.14-0.31 mg C m−2 h−1 after the peatland clearing. The land clearing of peatlands for agricultural practices also caused increases in CO2 and NOx emissions by 85% and 76%, respectively. Changes in GGH emissions were not related to the changes in substrates quality of peats (OC contents, total-N and hot water- soluble-C). Results of the study indicate that increases in the GHG emission following the use of peatlands for agricultural areas are attributed to the changes in the peat characteristics.
Community Participation in the Village Climate Program to Anticipate Future Climate Change in Wetlands
Authors: Nasruddin  , Kumalawati R , Syaharuddin  , Yuliarti A , Rajiani I
Published: June 2020

The issue of global warming and climate change is a crucial problem in the world as it triggers an increase in temperature and disasters. Indonesia one of the countries most vulnerable to climate change impacts. The impact of climate change is increasing every year. Efforts to reduce the impact of climate change on environmental management through climate village. Community participation is an important aspect of the success of the climate village program. The purpose of this study is how the Community Participation in the Village Climate Program to Anticipate Future Climate Change in Wetlands. This research method is quantitative. Sources of data in this study are primary data and secondary data. Sources of primary data obtained through interviews. Secondary data sources in the form of documentation and official archives that can support the research. Population and sample in the community in the village climate. Processing of data from interviews calculated percentages based on criteria of severe, moderate and good. Data in scoring with Likert scale approach and wide intervals. The analysis is based on the theory of Miles and Huberman. The findings of the study were to determine the Community Participation in the Village Climate Program to Anticipate Future Climate Change in Wetlands. Limitations of the study limit community participation in the climate village program. Community participation in the program is limited to mitigation and adaptation. The results showed community participation in the mitigation activities has been “good” and should be improved. Community participation in the activities of adaptation is “moderate”. This participation still needs improvements to community participation in the activities of adaptation to climate change can be better. Community participation is an important aspect of the success of the climate village program. Success climate village programs can reduce the negative impacts of future climate change on wetlands.
Land Suitability of Sebatik Island for Cocoa (Theobroma cacao L.)
Authors: Hidayanto Muhamad , Fiana Yossita , Hayati Afiah , Akas Pinaringan S.
Published: June 2020

The purpose of this research is to find out the land suitability class on Sebatik Island, Nunukan Regency, North Kalimantan Province for cocoa (Theobroma cacao L.) in accordance with the agroecosystem of the area. The method of this research is a literature study and field survey, sampling and soil analysis in the laboratory, and interviews to determine the land condition and potential of the land for cocoa. The results of the study show that land suitability class on Sebatik Island for cocoa, which is quite suitable (S2) 1.94% of the total area (473,36 ha), land class according to marginal (S3) 88.36% of the total area (21,056 ha), and inappropriate class land (N) 8.52% (2,089 ha). In each land suitability class (S2, S3, N) has a limiting factor for cocoa. The suitability class of S2, the limiting factors are the availability of water (wa), erosion hazards (eh) and nutrient availability (nr). Class S3 the limiting factors are water availability (wa), oxygen availability (oa), erosion hazard (eh), nutrient availability (nr) and rooting condition (rc). In the not suitability class (N), the limiting factor is sulfidic hazards and limited rooting conditions (rc).
Synthesis and Characterization of Sintered Magnetic Abrasive Particles having Alumina and Carbonyl Iron Powder
Authors: Alok Anupam , Niranjan M.S. , Kumar Abhinav , kumar Manjesh , Das Manas
Published: June 2020

The present workis focused on compacting, sintering, and characterization of sintered magnetic abrasive particles, which is composed of equal volume fraction of alumina and carbonyl iron powder. Powder metallurgy method is a well-developed technique for manufacturing of ferrous and nonferrous parts. AhO3–CIP composites are prepared through powder metallurgy method. Ball milling is used for mixing powders, and hydraulic Jack with die is used for compacting purpose. Solid and liquid phase sintering is performed at a high temperature tubular furnace under an inert gas atmosphere of argon. Solid and liquid phase sintering is done at 1000°C and 1545°C, respectively in proper consecutive sintering cycle. After sintering, the sintered pallets are crushed using ball miller to obtain the required size of the sintered powder. Energy Dispersive X-ray spectroscopy is used for elemental composition of all sintered powders. Vibrating sample magnetometer is used to see the magnetization of the particles. The saturation magnetization of the sintered abrasive obtained at 9–ton compaction pressure is found to be highest. Different phases of all prepared samples are studied using the X-ray diffraction technique. The morphology, as well as particle size, are studied using a scanning electron microscope. Also, the microstructure of sintered powders is studied using an optical microscope. Compression strength test of all sintered pallets is carried out using Universal Testing Machine. Bulk density of the pallets is measured using standard Archimedean principle. It is observed that the bulk density value increases with the compaction load. Micro hardness of the sintered pallets is measured using a Vickers micro hardness measuring instrument. The sintered pallet, fabricated at a compaction pressure of 9 ton shows the highest hardness.
Comparative deflection analysis of conical compression spring with standard constant rate helical spring
Authors: Mishra Akanksha , Aggarwal M.L.
Published: June 2020

Springs, indisputably find vast applications in different types of mechanical systems. Springs are utilized everywhere, right from simple playing toys to automobiles and dies. Stiffness is one of the most prominent factors for a spring. While the constant rate helical springs exhibit a linear behaviour, the conical springs display non-linear characteristics. The reason considered behind an increment in stiffness with an increase in deflection in case of conical springs is that the resistance offered by the small-diameter portion is more and hence, it deflects later compared to the larger diameter portion. In this paper, conical springs are studied experimentally under variable test conditions and an effort is made in the direction of further inducing the variable stiffness to a higher extent in the conical spring as compared to presently used constant rate springs for various special-purpose applications.
Surface Texturing by Electrochemical Micromachining: A Review
Authors: Kumar Abhinav , kumar Manjesh , Alok Anupam , Das Manas
Published: June 2020

The study of surface texturing has been a great interest to the researcher over the last years. Surface texturing improves the property of the surface of the material in the working area. It creates a pattern of micron dimensions over the surface to influence the surface property in its working area. Several techniques are used to fabricate these micro dimensions. Electrochemical micromachining (EMM) emerges as a new technique with several benefits. This review paper highlights the advantages of EMM over other processes and discusses different methods to develop the micro-features. EMM process is capable of fabricating micron-size features without changing any surface property at a low cost.
Study of Process Parameter and Microstructure of Freeze Casting Technology: A Review
Authors: Bhatt Mohit , Dhama Nikhil , Kumar Mohit , Singh Mithul , Kumar Sudhir , Singh Kanwar Pal , Kumar Arvind , Singh Vikram
Published: June 2020

Now a day various technologies are used for casting a product and freeze casting is one of them. Freeze casting is the process of casting a product at a lower freezing temperature for getting a porous structure. There are lots of factors that affect the freeze casting process like freezing temperature, freezing agent, slurry, additive, solid loading, freezing velocity, feed pressure etc. In this review paper, we focused the studying effect of this influencing parameter. This review paper highlights the research done by various researchers to optimize the input parameter for getting an economical and good quality of the cast product. An attempt has been made to conclude the effect of the range of process parameters and the comparison of various methods of freeze casting for the sound quality of cast products. In this paper, different freeze casting process parameters and their effect on the mechanical and Microstructural properties of the products are also summarized.
A Study on the Change of Displacement according to the Drainage Pump Outlet Shape and Size of Combat Equipment.
Authors: Kim Dae Un , Lee Ki Jung
Published: June 2020

Combat equipment is designed to cross the river on its own. The important thing here is that first, the inflow of water should be minimal, and the second is draining out the inside of the inflow. In this study, we have studied how to effectively discharge the incoming water. The purpose of this study is to compare the flow rate, so the pump pressure was not considered. The flow analysis was carried out only by considering the head pressure and atmospheric pressure. The outlet shape was found to have 13% more emissions than the spiral, which caused vortices due to the helical grooves and protrusions inside the hole, resulting in the loss of flow energy due to the increase in frictional resistance. As a result of checking the drainage according to the size, when the hole size is small, the drainage of water is gradually progressed. When the hole size is large, the drainage is increased rapidly and it is confirmed that it is discharged in a short time. If the hole size is infinite, the effect of drowning is maximized, but it may affect the structural strength of combat equipment, so it should be considered when designing the size of the outlet. Drainage pumps can save the combat equipment from the risk of flooding for water inflows below a certain level. Therefore, when the drainage pump is maintained, the pump is maintained, the pump efficiency should be guaranteed by thorough inspection and performance test.
Investigation of wear in a 3D printed Shaft – Bearing mechanism using different Lubricants
Authors: Jain Devanshu , Jain Akash , Singh Rc
Published: June 2020

Wear is the damaging, gradual removal or deformation of material at solid surfaces. The material loss due to wearing of interacting surfaces is a major concern. This not only decreases the life of the components that are interacting but also lead to various hazards. A lubricant is a substance, usually organic, introduced to reduce friction between surfaces in mutual contact, which ultimately reduces the heat generated when the surfaces interact. The experiment has been carried to study the wear rates of the tribopair and effect of lubricants on it. The shaft was fabricated by using an inhouse built 3-D printer. It is performed using a shaft-bearing mechanism. This research article discusses the study of measurement of the reduction in wear in the materials Polylactic Acid and an MDF board using HP grease AP3 and Loctite Maintain as two different lubricants.
Simulation and investigations on semiconductor materials and devices with surround gate geometry for high performance and low power nano scale applications
Authors: Singh Bhoop , Prasad B. , Kumar Dinesh
Published: June 2020

All The device with surround gate geometry provides a better way to scale down the dimensions and optimization of power and performance for nano scale applications. The superior gate control can be obtained by novel materials and innovative techniques for various regions of the nano scale device. The surround gate (SG) field effect transistor provides high gain, high trans-conductance, reduced short channel effects and conditions for scaling the technology to sub nano scale. The device has been modeled using SILCAVO Atlas3d and DevEdit3D module also used for creating the device structure with integration of multiple layers of different materials. In this paper surround gate device input (ID-VGS) and output (ID-VDS) characteristics have been intensively studied and parameters including ION/IOFF ratio, DIBL, sub threshold slope extracted and compared with the conventional devices. The silicon nanowire field effect transistor (SiNWFET) with surround gate geometry at 0.6 V applied between source and drain exhibits threshold voltage (VTH) 0.204 V, drain induced barrier lowering (DIBL) 172 mV/V, sub-threshold swing (SS) 104.23 mV/dec, ION=440.1μA, IOFF=1.04 μA and ION/IOFF ratio 4.24e+02. The results demonstrate improvement in device parameters for the SiNWFET device as compared to other conventional MOSFETs. The result obtained for SiNWFET are also compared with FinFET and CNTFET devices. This research also investigates the integration of alternate channel, dielectric and gate materials into novel GAA device structure.
Evaluation for Structural Integrity of Waste Plastic Cup Modified Bituminous Mix by Microchemical Analysis
Authors: Karmakar Sandip , Roy Tapas Kumar
Published: June 2020

Utilization of ultrasonic pulse velocity (UPV) to determine the stiffness of waste plastic cup (PC) modified HMA is considered as the “state of art” in this investigation. Besides, Fourier Transform Infrared (FTIR) spectroscopy and optical microscopy has been adopted to explore the hybridization as well as dispersion of PC droplets into the pristine bitumen for getting a homogeneous modified bitumen. Significant peak of H-C branch propagation at 2,700–3,300 cm 1 with inconspicuous carboxylic acid peak form FTIR spectroscopy has clarified a significant adhesive bitumen has been achieved for incorporating 2% PC in the pristine bitumen. However, even dispersion of PC modifier in the bitumen medium has justified its homogeneity for the cited dosage in the bitumen. Further, incremental trend in M.Q along with descending E value of the PC modified HMA has signified that beyond the aforementioned dosage such modified bitumen unable to coat the flaky basalt aggregate adequately in the HMA, thus air void may be formed in the HMA.
A new approach to identify similar users based on customer reviews
Authors: Chehal Dimple , Gupta Parul , Gulati Payal
Published: June 2020

Recommender System suggests items of interest to users based on their preferences. These preferences are gauged through various sources such as purchase history, ratings, reviews and browsing behaviour. Collaborative filtering and content based filtering are the two widely used techniques that help in generating recommendations to the target user(s) by identifying similar users to target user or similar items to items of interest. Through this paper a new method to identify similar users based on the similarity of reviews has been proposed.
Portable Rotary-angle Detector for Industrial Motor Inspection
Authors: Hsieh Tsung-Han , Chen Jr-Rung , Hsu Po-Er , Ho Bing-Lin
Published: June 2020

Several types of precision equipment, such as machine tools and robot arms, rely on precision rotary motion. In this study, we developed a portable rotary-angle detector (PRAD) comprising five optical sensors and one angle ring with a 57-mm diameter to measure the positioning and radial errors of rotary motions. The five optical sensors were installed at equally divided intervals around the angle ring according to the equal division averaged method (EDA-Method) implementation. The grating of the angle ring has 9000 lines, and the signal interpolation of the angle detector system has 4000-fold subdivision. Therefore, the PRAD resolution can be achieved at 0.036 arcsec. Furthermore, a 12-face polygon and an autocollimator with 0.05-arcsec resolution and 0.25-arcsec accuracy were used to check the PRAD performance. The experimental results showed that the structure of the PRAD is simple. However, the difference over 360° is only 0.7 arcsec, indicating that PRAD is suitable for motor inspection in machine tools or robot arms.
Energy-efficient Scheduling for Multistage Manufacturing System with Parallel Machines
Authors: Chang-pu MA , ZHOU Bing-hai , Yi SU
Published: June 2020

Increasing energy is prompting academicians to pay attention to energy efficient scheduling. This study establishes a mathematical model for multistage manufacturing system with parallel machines to minimize total energy consumption. A memetic algorithm based on differential evolution(MABDE) is developed to solve the model effectively. Two rules are incorporated into the proposed algorithm to narrow down the search space and improve search efficiency. Computational results demonstrate the effectiveness of the proposed model and algorithm.
Modelling public health benefits of various emission control options to reduce NO2 concentrations in Guangzhou
Authors: He Baihuiqian , Heal Mathew R , Reis Stefan
Published: June 2020

The local government of the megacity of Guangzhou, China, has established an annual average NO2 concentration target of 40 μg m−3 to achieve by 2020. However, the Guangzhou Ambient Air Quality Compliance Plan does not specify what constitutes compliance with this target. We investigated a range of ambition levels for emissions reductions required to meet different possible interpretations of compliance using a hybrid dispersion and land-use regression model approach. We found that to reduce average annual-mean NO2 concentration across all current monitoring sites to below 40 μg m−3 (i.e. a compliance assessment approach that does not use modelling) would require emissions reductions from all source sectors within Guangzhou of 60%, whilst to attain 40 μg m−3 everywhere in Guangzhou (based on model results) would require all-source emissions reduction of 90%. Reducing emissions only from the traffic sector would not achieve either interpretation of the target. We calculated the impacts of the emissions reductions on NO2-atttributable premature mortality to illustrate that policy assessment based only on assessment against a fixed concentration target does not account for the full public health improvements attained. Our approach and findings are relevant for NO2 air pollution control policy making in other megacities.
A refinement of the Ozsváth-Szabó large integer surgery formula and knot concordance
Authors: Truong Linh
Published: June 2020

We compute the knot Floer filtration induced by a cable of the meridian of a knot in the manifold obtained by large integer surgery along the knot. We give a formula in terms of the original knot Floer complex of the knot in the three-sphere. As an application, we show that a knot concordance invariant of Hom can equivalently be defined in terms of filtered maps on the Heegaard Floer homology groups induced by the two-handle attachment cobordism of surgery along a knot.
Non-degeneracy for the critical Lane–Emden system
Authors: Frank Rupert , Kim Seunghyeok , Pistoia Angela
Published: June 2020

We prove the non-degeneracy for the critical Lane–Emden system

−
Δ
U
=

V
p

,

−
Δ
V
=

U
q

,

U
,
V
>
0

in 

R

N

\begin{equation*} -\Delta U = V^p,\quad -\Delta V = U^q,\quad U, V > 0 \quad \text {in } \mathbb {R}^N \end{equation*}

for all

N
≥
3

N \ge 3

and

p
,
q
>
0

p,q > 0

such that

1

p
+
1

+

1

q
+
1

=

N
−
2

N

\frac {1}{p+1} + \frac {1}{q+1} = \frac {N-2}{N}

. We show that all solutions to the linearized system around a ground state must arise from the symmetries of the critical Lane–Emden system provided that they belong to the corresponding energy space or they tend to zero at infinity.
Nuclear weighted composition operators on weighted Banach spaces of analytic functions
Authors: Bonet José , Gómez-Collado M. , Jordá Enrique , Jornet David
Published: June 2020

We characterize nuclear weighted composition operators

W

ψ
,
φ

f
=
ψ
(
f
∘
φ
)

W_{\psi ,\varphi }f=\psi (f\circ \varphi )

on weighted Banach spaces of analytic functions with sup-norms. Consequences about nuclear composition operators on Bloch type spaces are presented. They extend previous work by Fares and Lefèvre on nuclear composition operators on Bloch spaces. Examples of nuclear as well as compact and non-nuclear weighted composition operators are given.
Global Cropland Connectivity: A Risk Factor for Invasion and Saturation by Emerging Pathogens and Pests
Authors: Xing Yanru , Hernandez Nopsa John F , Andersen Kelsey F , Andrade-Piedra Jorge L , Beed Fenton D , Blomme Guy , Carvajal-Yepes Mónica , Coyne Danny L , Cuellar Wilmer J , Forbes Gregory A , Kreuze Jan F , Kroschel Jürgen , Kumar P Lava , Legg James P , Parker Monica , Schulte-Geldermann Elmar , Sharma Kalpana , Garrett Karen A
Published: June 2020

The geographic pattern of cropland is an important risk factor for invasion and saturation by crop-specific pathogens and arthropods. Understanding cropland networks supports smart pest sampling and mitigation strategies. We evaluate global networks of cropland connectivity for key vegetatively propagated crops (banana and plantain, cassava, potato, sweet potato, and yam) important for food security in the tropics. For each crop, potential movement between geographic location pairs was evaluated using a gravity model, with associated uncertainty quantification. The highly linked hub and bridge locations in cropland connectivity risk maps are likely priorities for surveillance and management, and for tracing intraregion movement of pathogens and pests. Important locations are identified beyond those locations that simply have high crop density. Cropland connectivity risk maps provide a new risk component for integration with other factors—such as climatic suitability, genetic resistance, and global trade routes—to inform pest risk assessment and mitigation.
Haploinsufficiency of Tsc2 Leads to Hyperexcitability of Medial Prefrontal Cortex via Weakening of Tonic GABAB Receptor-mediated Inhibition
Authors: Bassetti Davide , Lombardi Aniello , Kirischuk Sergei , Luhmann Heiko J
Published: June 2020

Loss-of-function mutation in one of the tumor suppressor genes TSC1 or TSC2 is associated with several neurological and psychiatric diseases, including autism spectrum disorders (ASDs). As an imbalance between excitatory and inhibitory neurotransmission, E/I ratio is believed to contribute to the development of these disorders, we investigated synaptic transmission during the first postnatal month using the Tsc2+/− mouse model. Electrophysiological recordings were performed in acute brain slices of medial prefrontal cortex. E/I ratio at postnatal day (P) 15–19 is increased in Tsc2+/− mice as compared with wildtype (WT). At P25–30, facilitated GABAergic transmission reduces E/I ratio to the WT level, but weakening of tonic GABAB receptor (GABABR)-mediated inhibition in Tsc2+/− mice leads to hyperexcitability both at single cell and neuronal network level. Short (1 h) preincubation of P25–30 Tsc2+/− slices with baclofen restores the GABABR-mediated inhibition and reduces network excitability. Interestingly, the same treatment at P15–19 leads to weakening of GABABR-mediated inhibition. We hypothesize that a dysfunction of tonic GABABR-mediated inhibition might contribute to the development of ASD symptoms and suggest that GABABR activation within an appropriate time window may be considered as a therapeutic target in ASD.
Differences in adrenocortical responses between urban and rural burrowing owls: poorly-known underlying mechanisms and their implications for conservation
Authors: Palma Antonio , Blas Julio , Tella José L , Cabezas Sonia , Marchant Tracy A , Carrete Martina
Published: June 2020

The hypothalamus–pituitary–adrenal/interrenal (HPA) axis of vertebrates integrates external information and orchestrates responses to cope with energy-demanding and stressful events through changes in circulating glucocorticoid levels. Urbanization exposes animals to a wide variety of ever-changing stimuli caused by human activities that may affect local wildlife populations. Here, we empirically tested the hypothesis that urban and rural owls (Athene cunicularia) show different adrenocortical responses to stress, with urban individuals showing a reduced HPA-axis response compared to rural counterparts to cope with the high levels of human disturbance typical of urban areas. We applied a standard capture-restraint protocol to measure baseline levels and stress-induced corticosterone (CORT) responses. Urban and rural owls showed similar circulating baseline CORT levels. However, maximum CORT levels were attained earlier and were of lower magnitude in urban compared to rural owls, which showed a more pronounced and long-lasting response. Variability in CORT responses was also greater in rural owls and contained the narrower variability displayed by urban ones. These results suggest that only individuals expressing low-HPA-axis responses can thrive in cities, a pattern potentially mediated by three alternative and non-exclusive hypotheses: phenotypic plasticity, natural selection and matching habitat choice. Due to their different conservation implications, we recommend further research to properly understand wildlife responses to humans in an increasingly urbanized world.
Cognitive Behavioral Therapy for Insomnia: A Promising Treatment for Insomnia, Pain, and Depression in Patients With IBD
Authors: Salwen-Deremer Jessica K , Siegel Corey A , Smith Michael T
Published: June 2020

Over 75% of people with active inflammatory bowel diseases (IBDs) report sleep disturbances, which heighten risk for IBD relapse and flares. Despite mounting evidence for sleep disturbances in IBD, discussion of treatment is severely limited. The most common sleep disturbance, insomnia, occurs in over 50% of adults with chronic health conditions. Herein we describe the gold standard treatment for insomnia, Cognitive Behavioral Therapy for Insomnia (CBT-I). Although yet to be studied in IBD, CBT-I reduces a number of IBD-related comorbidities, including chronic pain, depression, and systemic inflammation. We describe treatment with CBT-I, the impact of CBT-I on these comorbidities, and recommendations for providers.
Influence of Religiousness and Spirituality on Remission Rate, Mental Health, and Quality of Life of Patients With Active Crohn’s Disease: A Longitudinal 2-Year Follow-up Study
Authors: de Campos Renata Jacob Daniel Salomão , Lucchetti Giancarlo , Lucchetti Alessandra Lamas Granero , Chebli Liliana Andrade , Schettino Pereira Luiza , Chebli Julio Maria Fonseca
Published: June 2020

Background and Aims

Studies on inflammatory bowel disease [IBD] have shown that religiousness and spirituality [R/S] were associated with better mental health and quality of life [QOL]. However, longitudinal studies assessing the impact of R/S on long-term clinical outcomes of Crohn’s disease [CD] are scarce. The aim of this study was to assess the influence of R/S on the course of CD after a 2-year follow-up and to determine whether these R/S beliefs were associated with mental health and QOL.

Methods

A longitudinal 2-year follow-up study was conducted at a referral centre for IBD, including patients with moderately to severely active CD. Clinical data, disease activity [Harvey-Bradshaw Index], QOL [Inflammatory Bowel Disease Questionnaire-IBDQ], depression and anxiety [Hospital Anxiety and Depression Scale-HADS], and R/S [Duke Religion Index-DUREL, Spirituality Self-Rating Scale-SSRS, and Spiritual/Religious Coping-SRCOPE scale] were assessed at baseline and at the end of the 2-year follow-up. Linear and logistic regression models were employed.

Results

A total of 90 patients [88.2%] were followed up for 2 years. On logistic regression, baseline levels of spirituality (odds ratio [OR] = 1.309; 95% confidence interval [CI]= 1.104–1.552, p = 0.002) and intrinsic religiousness [OR = 1.682; 95% CI = 1.221–2.317, p = 0.001] were predictors of remission at 2 years. On linear regression, the different dimensions of R/S did not significantly predict IBDQ or anxiety and depression scores after 2 years.

Conclusions

R/S predicted remission of CD patients after a 2-year follow-up. However, these beliefs failed to predict mental health or QOL. Health professionals who treat CD should be aware of the religious and spiritual beliefs of their patients, given these beliefs may impact on the disease course.
Differing mechanisms of atrial fibrillation in athletes and non-athletes: alterations in atrial structure and function
Authors: Trivedi Siddharth J , Claessen Guido , Stefani Luke , Flannery M Darragh , Brown Paula , Janssens Kristel , Elliott Adrian , Sanders Prashanthan , Kalman Jonathan , Heidbuchel Hein , Thomas Liza , La Gerche Andre
Published: June 2020

Aims

Atrial fibrillation (AF) is more common in athletes and may be associated with adverse left atrial (LA) remodelling. We compared LA structure and function in athletes and non-athletes with and without AF.

Methods and results

Individuals (144) were recruited from four groups (each n = 36): (i) endurance athletes with paroxysmal AF, (ii) endurance athletes without AF, (iii) non-athletes with paroxysmal AF, and (iv) non-athletic healthy controls. Detailed echocardiograms were performed. Athletes had 35% larger LA volumes and 51% larger left ventricular (LV) volumes vs. non-athletes. Non-athletes with AF had increased LA size compared with controls. LA/LV volume ratios were similar in both athlete groups and non-athlete controls, but LA volumes were differentially increased in non-athletes with AF. Diastolic function was impaired in non-athletes with AF vs. non-athletes without, while athletes with and without AF had normal diastolic function. Compared with non-AF athletes, athletes with AF had increased LA minimum volumes (22.6 ± 5.6 vs. 19.2 ± 6.7 mL/m2, P = 0.033), with reduced LA emptying fraction (0.49 ± 0.06 vs. 0.55 ± 0.12, P = 0.02), and LA expansion index (1.0 ± 0.3 vs. 1.2 ± 0.5, P = 0.03). LA reservoir and contractile strain were decreased in athletes and similar to non-athletes with AF.

Conclusion

Functional associations differed between athletes and non-athletes with AF, suggesting different pathophysiological mechanisms. Diastolic dysfunction and reduced strain defined non-athletes with AF. Athletes had low atrial strain and those with AF had enlarged LA volumes and reduced atrial emptying, but preserved LV diastolic parameters. Thus, AF in athletes may be triggered by an atrial myopathy from exercise-induced haemodynamic stretch consequent to increased cardiac output.
A case report of Adult-onset Still’s disease as a cause of severe mitral regurgitation
Authors: Shah Shabir Hussain , Shah Muhammad Azam , Khan Mohammad Shahbaz , Alghamdi Faisal Abdullah
Published: June 2020

Background

Adult-onset Still’s disease (AOSD) is an uncommon systemic inflammatory disease, causing spiking fever, skin rash, and arthritis. Pericarditis and myocarditis are the most common cardiac manifestation of AOSD but valvular involvement is rarely reported.

Case summary

An 18-year-old boy presented with gradually worsening shortness of breath for 6 months. There was a history of low-grade intermittent fever and polyarthralgia affecting ankles, knees, and elbows. He was in heart failure with cardiogenic and septic shock. He was managed initially with antibiotics, inotropes, and diuretics. Echocardiography showed flail anterior mitral leaflet with severe mitral regurgitation. He remained febrile with persistent negative blood cultures. Intravenous antibiotics led to neutropenia without any response to fever and clinical status. On further workup, he was diagnosed to have AOSD, and he responded dramatically to oral steroid therapy. Later his mitral valve was replaced surgically. On follow-up, he was stable with mild exertional dyspnoea. His international normalized ratio was in therapeutic range and his follow-up echocardiography showed normally functioning mitral prosthesis. He is following rheumatology and currently on the maintenance dose of steroids.

Discussion

Adult-onset Still’s disease is a systemic illness with diagnosis is based on clinical features and exclusion of other illnesses. Adult-onset Still’s disease should be considered as a differential diagnosis in culture-negative endocarditis, especially in those with systemic features and non-responders to antibiotics.
When the left atrium becomes a monster: a case report
Authors: Shams Khaled A
Published: June 2020

Background

Congenital left atrium (LA) aneurysms are extremely rare entities in clinical practice and most frequently involve the atrial appendage and rarely arise from the body of LA, We report a case of giant LA aneurysm compressing heart and presenting in a very late stage.

Case summary

A 31-year-old male, who was diagnosed to have dextrocardia, rheumatic heart disease, and atrial fibrillation and was kept on medical treatment long time ago, presented with congestive heart failure symptoms and cardiogenic shock. Emergency transthoracic echocardiography was done revealing situs solitus with aneurysmally dilated LA pushing heart to the right side (dextro-posed heart), moderate mitral regurgitation, and severe pulmonary hypertension, however, pulmonary artery anatomy could not be properly visualized so computed tomography (CT) was preformed confirming diagnosis and revealing compressed pulmonary arterial tree by the dilated LA, unfortunately patient died before proceeding to surgical intervention.

Discussion

Congenital left atrial aneurysms are extremely rare anomaly and may be associated with significant morbidity. And, therefore, should be remembered as a potential anatomic cause of atrial arrhythmias or embolic phenomena, or both. The diagnosis may be easily established through non-invasive complementary techniques, such as echocardiography, CT, and cardiac magnetic resonance imaging. Symptomatic patients, those with large aneurysm or compelling indications for surgery should undergo surgical resection.
Listeria myopericarditis associated with right atrial mural thrombus: a case report
Authors: Brown Andrew , Abbas Mohamed , Runnett Craig , Ripley David Paul
Published: June 2020

Background 

Pericarditis is a common cardiology presentation, most often due to a viral or idiopathic cause. Listeria as a cause of pericarditis is rare. Listeria is an infection that is readily treatable with antibiotics following accurate identification. Without adequate treatment, Listeria infection has a high mortality rate.

Case summary 

In this case, a fit and well 59-year-old man complained of headaches and fever to the emergency department (ED). He was provisionally diagnosed with giant cell arteritis (GCA) and commenced on management pathways for GCA. He represented to the ED with chest pain and electrocardiogram (ECG) changes suggestive of a clinical presentation of pericarditis. He received treatment for idiopathic pericarditis with no clinical resolution. Cardiac magnetic resonance imaging (MRI) showed myopericardial inflammation associated with a right atrial mural thrombus. After 2 weeks of poor treatment response, peripheral blood cultures grew Listeria monocytogenes and the patient responded well to antibiotic treatment. Repeat cardiac MRI after an extended course of antibiotics showed resolution of MRI signs.

Discussion 

This is a case of Listeria myopericarditis. Physicians should consider rarer causes of myopericarditis in treatment resistance cases. Cardiac MRI has utility in atypical or treatment resistant patients to assess myopericardial inflammation and response to treatment.
Fast spontaneous recovery from acute necrotizing eosinophilic myopericarditis without need for immunosuppressive therapy: a case report of a 27-year-old male
Authors: Kindermann Michael , Sood Nitin , Ehrlich Peter , Klingel Karin
Published: June 2020

Background

Eosinophilic myocarditis (EM) is rare but accounts for 12–22% of histologically proven acute myocarditis cases. Acute necrotizing EM is considered an aggressive, life-threatening disease which is usually treated by high-dose corticosteroid therapy.

Case summary

We report the case of a 27-year-old man with acute severe pericarditic chest pain, moderately reduced left ventricular (LV) ejection fraction, and a small pericardial effusion. Troponin I level was highly elevated in the absence of coronary artery disease, leading to the diagnosis of acute myopericarditis. In the absence of blood eosinophilia and despite a negative cardiac magnetic resonance study, LV endomyocardial biopsy revealed an acute necrotizing EM. With conventional antiphlogistic and heart failure therapy, the patient became symptom-free and inflammatory and cardiac necrosis markers as well as LV ejection fraction normalized within days. Thus, in the absence of a systemic hypereosinophilic disorder, there was no need for steroid therapy. Long-term follow-up over 12 months showed sustained normalization of cardiac structure and function.

Discussion

Acute necrotizing eosinophilic myopericarditis is not always a dreadful cardiac disease. There are idiopathic cases which may quickly resolve without immunosuppression. There seems to be a publication bias towards critical cases.
Comparative overview of ST-elevation myocardial infarction epidemiology, demographics, management, and outcomes in five Asia-Pacific countries: a meta-analysis
Authors: Tern Paul Jie Wen , Ho Aaron Kwun Hang , Sultana Rehena , Ahn Youngkeun , Almahmeed Wael , Brieger David , Chew Derek P , Fong Alan Yean Yip , Hwang Jinyong , Kim Yongcheol , Komuro Issei , Maemura Koji , Mohd-Ali Rosli , Quek David Kwang Leng , Reid Christopher , Tan Jack Wei Chieh , Wan-Ahmad Wan Azman , Yasuda Satoshi , Yeo Khung Keong
Published: June 2020

The aim of this study is to gain insight into the differences in demographics of ST-elevation myocardial infarction (STEMI) patients in Asia-Pacific, as well as inter-country variation in treatment and mortality outcomes. Systematic review of published studies and reports from known registries in Australia, Japan, Korea, Singapore, and Malaysia that began data collection after the year 2000. Supplementary self-report survey questionnaire on public health data answered by representative cardiologists working in these countries. Twenty studies comprising of 158 420 patients were included in the meta-analysis. The mean age was 61.6 years. Chronic kidney disease prevalence was higher in Japan, while dyslipidaemia was low in Korea. Use of aspirin, P2Y12 inhibitors, and statins were high throughout, but ACEi/ARB and β-blocker prescriptions were lower in Japan and Malaysia. Reperfusion strategies varied greatly, with high rates of primary percutaneous coronary intervention (pPCI) in Korea (91.6%), whilst Malaysia relies far more on fibrinolysis (72.6%) than pPCI (9.6%). Similarly, mortality differed, with 1-year mortality from STEMI was considerably greater in Malaysia (17.9%) and Singapore (11.2%) than in Korea (8.1%), Australia (7.8%), and Japan (6.2%). The countries were broadly similar in development and public health indices. Singapore has the highest gross national income and total healthcare expenditure per capita, whilst Malaysia has the lowest. Primary PCI is available in all countries 24/7/365. Despite broadly comparable public health systems, differences exist in patient profile, in-hospital treatment, and mortality outcomes in these five countries. Our study reveals areas for improvements. The authors advocate further registry-based multi-country comparative studies focused on the Asia-Pacific region.