bluuebunny/crossref_metadata_2025 huggingface dataset:
Cultural Substance Actualization in Spatial Planning: Case of Cirebon City, Indonesia
Authors: Agustina Ina Helena , Fardani Irland , Aji Riswandha Risang
Published: October 2021

Cirebon city which located in West Java Province, is a city that is created due to the existence of a kingdom. The former kingdom cites from the past still stand until today in the form of keraton, whether its building, the king or the community. Cultural identity of keraton has not become synergic with the spatial plan of Cirebon City, and this often leads to a spatial conflict during the implementation. A conflict both in the form of function or value which is not actualized in spatial management. The synergy of space and culture could support the sustainability of a city space, as well as the sustainability of Cirebon City which is wealthy in culture. Cultural identity in the form of a space could provide attractiveness of a city as referred to the statement of UNESCO (2015). Cirebon city has not owned a legal culture-based documents that supports the implementation of the spatial plan. The aim of this paper is to formulate the concept of cultural substance in spatial planning of Cirebon City. The approach method used is qualitative method with hermeneutic approach through text. The result is the finding of a concept that shows leadership and collective awareness to the urgency of culture that is embraced by Keraton as the form of cultural identity actualization and as Cirebon city spatial planning document substance directions.
Sumatra Island Economic Cluster
Authors: Saraswati Zenia F , Pramudhita Nefertari , Pradono Prof , Sefianiz Dabi , Hidayatullah Ricky
Published: October 2021

The growth of a region cannot be released from its position in a larger urban system. Interactions in urban systems manifest in various forms such as population migration, trade, and information exchange. These interactions then have an influence on other regions. One of the expected outcomes of urban interaction is economic growth. However, not all regions can have a positive influence in their interactions in urban systems. This influence can be seen through spatial spreads that occur in existing economic indicators. This research seeks to look at clusters of economic activity on Sumatra Island because of the urban interactions that occur. This research uses the LISA method on economic data of 172 districts under the administrative area of the island of Sumatra. It is seen that the spatial distribution of economic activity is not random. There are several clusters of economic activity following the concentration of the population on the island of Sumatra namely in the area around Medan and Lampung. This spatial arrangement has no significant change between the two years of observation. While population and quality of transportation have a strong relationship, but these two variables do not appear to have a relationship with the GDRP of transportation
Distribution of peak ground acceleration in Pandeglang Regency, Banten
Authors: Lestari D A , Fitriasari N S , Ahmad T E , Azhari D R , Rais A
Published: October 2021

Pandeglang Regency is an area prone to earthquakes because in the subduction zone of the Indo-Australian plate and the Eurasian plate in the Sunda Strait. This study analyses the average and maximum values of the Peak Ground Acceleration (PGA) got from earthquakes in the period 2000 to 2020 around Pandeglang Regency with the calculation method. Gutenberg-Richter with the Richter formula combined with the intensity attenuation formula which is a function of magnitude, epicentre distance, and earthquake intensity. From the maximum PGA data, the lowest value is 273 gals, and the highest is 427.5 gals. Meanwhile, for the distribution of the average PGA value, the minimum value is 54 gals, and the maximum value is 67 gals. From the PGA data, the maximum distribution of the highest PGA value is in the center of Pandeglang Regency, and the lowest value of the PGA maximum is in the northern and southern parts of Pandeglang Regency. The PGA value is potentially damaging at the VII MMI scale, where the area with the highest vulnerability is in the sub-district Angsana, Munjul, Panimbang, and Sidangresmi with the highest PGA scores, so this sub-district has the highest risk than other districts.
Thermal properties of kenaf fiber-based nanocellulose reinforced polyurethane composites
Authors: Feborando R , Juwono A L , Roseno S
Published: October 2021

Natural fibers made into cellulose have attracted interest in the research and development of composite materials in recent years. One of them is Kenaf fiber from Sumberejo, East Java. The Kenaf fiber nanocellulose reinforced polyurethane (NC-PU) composites were prepared via in-situ polymerization. The purpose of this research is to analyze the thermal properties and morphology of PU and NC-PU composites. Then, TGA (thermogravimetric analysis), DTG (differential thermogravimetric analysis), DSC (differential scanning analysis) and SEM (scanning electron microscope) are applied to characterize PU and NC-PU composites. The addition of nanocellulose up to 7 wt.% in polyurethane was found to decrease the melting temperature of NC-PU composites and decrease the rate of decomposition. The lowest decomposition rate is attributed to the composite material of 10 wt.% NC-PU, which has a decomposition rate of 1.7 %/min, and the highest residual decomposition rate of 67 %. The addition of nanocellulose to PU also decreases the average pore size of NC-PU composites
Social vulnerability of Pandeglang Regency, Banten
Authors: Lestari D A , Fitriasari N S , Azhari D R , Ahmad T E , Rais A
Published: October 2021

The potential for natural disasters in Pandeglang Regency is enormous considering that various kinds of disasters can occur in Pandeglang Regency. There needs to be comprehensive efforts to reduce the impact of the risk of natural disasters, one of them is by knowing the level of social vulnerability of the community in Pandeglang. Social vulnerability calculates the level of social vulnerability of the community to scenarios of natural disasters. This study aims to determine the level of social vulnerability and its distribution. Concept method of Social Vulnerability Index (SOVI) is used to measure regional vulnerability based on social indicators to disasters using the aspects of exposure, sensitivity and adaptive capacity. The variables used are population density, proportion of informal sector workers, proportion of vulnerable age population, proportion of non-permanent houses, proportion of prosperous households, proportion of high school graduates and number of social institutions. The level of vulnerability that dominates is a low vulnerability area by number 25 sub-districts or 71.42 % while there are 9 sub-districts or 25.71 % for high vulnerability areas and only 1 sub-district or 2.85 % of high vulnerability areas, namely Cimanuk District, which is in the northern part of Pandeglang Regency. Based on the value of vulnerability in several areas that still show a fairly large level of medium-high vulnerability. So, this data can be used as a recommendation as early mitigation measures to reduce the level of social vulnerability in order to reduce the impact that will later be caused.
Determination of bedrock depth in Universitas Indonesia using the seismic refraction method
Authors: Herlambang N , Riyanto A
Published: October 2021

The seismic refraction method is used to determine the exact bedrock depth for placing a foundation pole. The study was conducted in Universitas Indonesia precisely at the Fasilkom Universitas Indonesia complex. The seismic survey configuration consists of 24 geophone channels with a length of 67.5 m, geophone intervals of 2.5 m, and near offset of 10 m. The wave source was generated using a hammer, and the distance between blows was 5 m. The secondary data used was geological data from SPT (Soil Penetration Test) borehole as a reference for comparison of seismic survey results. Seismic refraction data was processed using traditional techniques, namely the Hagedoorn’s Plus-Minus Method and tomographic inversion using Rayfract software. The correlation between the results of the process with the geological data from SPT drill point shows good results. However, the Plus-Minus Haggedorn method results are only able to show one refractor because of the data limitation, in contrast to the inversion method, which was able to show more than one refractor. There are two main refractors at a depth of 6 meters and 12 meters, and the adequate depth obtained only reaches 15 m. The maximum speed obtained is also around 900 m/s. It can be concluded up to a depth of 15 meters, and there is no recommended rock layer for placement of deep foundations for high rise buildings. A seismic survey with a longer seismic line is needed to get an underground picture exceeding 15 meters.
Seismic wave attenuation in carbonate rock and its implication to hydrocarbon-bearing reservoir identification, East Java, Indonesia
Authors: Sadat A , Haris A , Haryono  , Riyanto A , Dharmawan G A
Published: October 2021

The heterogeneity of carbonate rock properties triggers propagated seismic wave to get some attenuations. This mechanism allows that attenuation can be applied in hydrocarbon exploration to identify lithology, porosity, fluid content and fracture identification. Unfortunately, to measure the degree of attenuation, the sophisticated tools and advanced processing technology are required. Thus, some methods were formulated to estimate attenuation. This study is aimed to estimate and compare attenuation from wireline log interpretation by using four different methods. The study is also supported by a series of exploration wells penetrating Kujung I Formation in northwestern edge of North East Java Basin, Indonesia. The result shows that only Qs from Zhang et al method is overestimate. P-wave quality factor of Klimentos and Zhang methods and scaled quality factor (SQp and SQs) method are sensitive to identify hydrocarbon. Furthermore, lithofacies also affects estimated rock quality factor. The novelty of study is to estimate and compare the attenuation from different method and review its result and application in hydrocarbon identification, especially for carbonate reservoir in North East Java basin, Indonesia. So that, a new understanding of attenuation characteristic in carbonate reservoir contributes to discriminate pore fluid identification in hydrocarbon exploration.
Distribution analysis of brittleness index, modulus young, modulus bulk, and Poisson’s ratio using the integration of refraction seismic method and MASW case study of Fasilkom UI’s new building
Authors: Rizqulloh M R , Riyanto A
Published: October 2021

This research was conducted by validating the results of the SPT data collection that had been previously taken using geophysical methods in the engineering and environmental fields. This study can help to determine the subsurface lithology used to find the right building foundation. This research conducting to determine the distribution of the Brittleness value and the rock mechanic parameter values below the surface of the cross-section of the refractive seismic data processing in the field of the case study of Fasilkom UI’s new building in January 2020. Analysis of the distribution of Brittleness values and rock mechanics was carried out based on the calculation of Vp and Vs values obtained from processing the results of data acquisition and supporting data in the form of data (Soil Penetration Test) SPT. The 2D cross-section of rock mechanic parameters are Poisson’s Ratio has results ranging from -1 to 0.5, bulk modulus has resulted in the range 0 to 5.4, and modulus young has resulted in the range 0 to 9.5. The distribution of Brittleness values below the surface of the first and second layers is dominated by the brittle layer, the third layer is the distribution of the brittle and ductile layers, the fourth and fifth layers are dominated by ductile layers.
Coal Bottom Ash as a Potential Adsorbent for CO2 Capture
Authors: Rani N H A , Mohamad N F , Onn M , Jalil M J , Muda N
Published: October 2021

Coal bottom ash (CBA) is the solid residue produced from coal-fired power plant. It is classified as hazardous material, which can cause adverse effect to the environment and public health. In view of the situation, exploring and discovering possible utilization of these coal residues into value-added products has to be performed. Hence, the aim of this paper is to investigate the potential of raw CBA as an adsorbent for carbon dioxide (CO2) gas adsorption. The physicochemical characteristics of CBA were determined using ultimate and proximate analysis, nitrogen adsorption-desorption isotherm, scanning electron microscopy (SEM), and elemental diffraction x-ray (EDX) analysis. CO2 adsorption study was conducted using simulated flue gas by pressure swing adsorption process in a fixed-bed reactor to evaluate the suitability of CBA as an adsorbent material. High carbon content in CBA makes it’s become a good precursor for production of carbonaceous adsorbent. Trace elements like calcium, silica and alumina, indicating that the material had a good adsorption capacity. The result indicated that CBA was able to adsorb CO2 with the adsorption capacity of 0.000276 mol CO2/g CBA. As a conclusion, CBA has the potential to be an adsorbent for its application in gas phase especially in CO2 adsorption.
Characterisation of microfibrils cellulose isolated from oil palm frond using high-intensity ultrasonication
Authors: Yashim M M , Mohammad M , Asim N , Fudholi A , Abd Kadir N H
Published: October 2021

This study highlighted the utilization of agricultural byproducts as an alternative fiber resource to be used as one of the materials for reinforcement biocomposite. Cellulose was extracted from oil palm frond using the alkaline treatment and successfully isolated into microfibril via the combination of carboxymethylation pre-treatment ultrasonication to get highly crystalline and good thermal stable microfibers. 4% NaOH was used during alkaline treatment and followed by oxidative bleaching with 30% H2O2. Once the extracted cellulose is chemically pre-treated with monochloroacetic acid, it was subjected to 30 minutes ultrasonication treatment to reduce its size. The detailed comparative analysis using SEM, FTIR and TGA was conducted in this work revealed some breakages of intramolecular hydrogen bonds and glycosidic bonds that occurred during the alkaline and bleaching treatment of oil palm biomass. The SEM images showed significant morphology of rigid, organized and highly ordered cellulose fibrils changed into aggregated fibril bundles of microfibrils after ultrasonication. The results from the infrared spectrums revealed that the mild alkaline treatments and oxidative bleaching were able to remove a large fraction of lignin and hemicelluloses to leave a clean cellulose sample. The isolated microfibrils cellulose exhibit good thermal stability as almost 50% of its initial mass remains at a temperature of 300 °C. These findings demonstrate that oil palm fronds can be utilized for biocomposite reinforcement applications.
Effectiveness of Annona Squamosa and Annona Muricata Seed Extracts as Ingredients in Bio-pesticides Spray
Authors: Irwan Z , Kamarudin W F W , Korish U A S A , Z N A , Rusli A S , Sallehuddin S
Published: October 2021

Pesticides released chlorofluorocarbon (CFC) that can harm to the environment and human health. Therefore, it is a need for development of an alternative methods in pest management due to negative effects of pesticides for human health and the environment. The objective of this study was to evaluate the effectiveness of Annona Squamosa and Annona Muricata seed extracts as ingredients in bio-pesticides spray on killing crickets (Gryllidae) and mealworm (Tenebriomolitor). The seeds of Annona Squamosa and Annona Muricata were dried, powdered and extracted in soxhlet’s apparatus using n-hexane as a solvent at 60°C. The extracted oil was placed in the rotary evaporator for purification process. As a result, mixture of extracts of Annona muricata and Annona squamosa induced high mortality rate to mealworm and cricket compared to extracts of Annona squamosa and extract of Annona muricata at all concentrations tested. Therefore, the extracts of these Annona muricata and Annona squamosa may be used as one of the alternatives as bio-pesticides that offer cheaper and environmentally friendly method.
Effects of Disposed-water from Barapukuria Coal Mine, Dinajpur, Bangladesh on Agriculture and Aquaculture
Authors: Rahman M T , Khan A H , Negash B M , Sultana K , Hasan M A , Askary A , Rubbi F , Das L
Published: October 2021

The environment is a prime concern in the mining industry because of its adverse impact on the solid, liquid, and gaseous surroundings. These three parts of the environment are directly connected to agricultural production. As the Barapukuria coal mine is located in the agricultural zone, its effects can be crucial. Previously, the impacts of the subsidence of the Barapukuria coal mining area were studied. So far, there is no significant study regarding its effects on agriculture. This research has focused on the impacts of the disposed water from the Barapukuria coal mine on the nearer aquaculture and agricultural fields. Therefore, the BOD, COD, DO, TDS, TSS, SS, residual chloride, hardness, alkalinity, carbon, sodium, calcium, magnesium, iron, potassium, sulphate, etc., being present in the disposed-water were analyzed in this study. The values of BOD, COD, DO, pH, TSS, TDS, and TS were lied in the best optimum range to cultivate crops and fisheries. It is also found that the disposed-water of the Barapukuria coal mine is tolerable for agriculture.
Removal of Reactive Orange 16 Dye using Casuarina equisetifolia seeds as Packing Media for Microbial Biofilm Formation
Authors: Osman W H W , Tan M M , Rashid A A A , Mohd N , Mohammad R
Published: October 2021

Dyes effluent mostly is toxic and mutagenic to living organism. Casuarina equisetifolia seeds are usually found in coastal and have potential as a packing media for microbial biofilm formation. The present study was designed to evaluated the performance of three laboratory scale reactors namely, sequencing batch biofilm reactor (CES-SBBR), a combination of adsorption and biological process, sequencing batch biofilm reactor (FC-SBR), and packed bed reactor (CES-PBR) on the removal of RO16 dye. The CES-SBBR and CES-PBR were packed with Casuarina equisetifolia seeds. The microorganism was collected from textile industry and undergo the preadaptation period with the 2 mg/L of RO16 solutions in CES-SBBR and FC-SBR. The biomass concentration initially reduced from 0.12 to 0.03 mg/L. Upon the addition of nutrients, the biomass concentration was increased to 0.22 mg/L. The performance study of three reactors was performed with the initial concentration of RO16 solution and hydraulic retention time (HRT) of 2 mg/L and 24 hr, respectively. The RO16 dye removal efficiencies were in range of 80.00-82.26%. The removal efficiencies were reduced to 70.00-71.28% when the initial concentration of RO16 dye increased to 4 mg/L. The removal efficiencies were continued to reduce with only 48.06-50.00% as the initial concentration of RO16 dye increased to 6 mg/L. The removal efficiencies were improved when the HRT was extended to 48 hr. The biomass concentration of CES-SBBR and FC-SBR increased up to 0.50 and 0.33 mg/L, respectively. The RO16 removal percentage for FC-SBR and CES-PBR were found to be lower compared to as for CES-SBBR. This study shows that the combination of adsorption and biological process enhanced the removal efficiency of RO16 dye.
Optimization of AB Fertilizer for Plant Growth in Fertigation Using Central Composite Design
Authors: Draman S F S , Shukri S M , Ishak N S I , Samad A S A , Pauzi A F
Published: October 2021

A plant needs to consume sufficient essential nutrients for production speed. This study investigated the optimum condition for water spinach growth of wick technique fertigation. Fertigation is a fertilizer application process in which the drip system mixes fertilizer within the irrigation water. The fertilizer solution is uniformly distributed in the irrigation system. The chosen method is a hydroponic method and suitable in an urban area with no soil for planting. Fertigation is also an easy and cost-effective method. The water spinach height’s optimum condition was determined through the central composite design (CCD) as the experiment (DOE) design. The critical factors selected for this study were the concentration of AB fertilizer and wick length. Obtaining an adequate AB fertilizer concentration is crucial because it will affect the growth of water spinach. The statistical analysis based on a CCD showed that 1.5 mL of AB fertilizer concentration (volume/volume) and 12 cm of wick length were the optimum conditions to achieve the best water spinach growth in 21 days. The CCD as a response surface method was proved to help obtain optimum water spinach plant growth conditions.
The Design of IoT Dengue Alert Supervisions System with RFID Access
Authors: Mamat W M K W , Kassim M , Shahbudin S , Ya’acob N
Published: October 2021

This research presents a development of a patient’s Dengue Alert Supervisions (DAS) System. The system is designed adaptively to alert patients and can be monitored over the Microsoft Windows Interfacing Applications system. The purpose is to alert patients on dengue attacks if they are possibly infected with dengue. Problem identifies that patients are difficult and hard to go for regular medical check-ups especially to the hospital. They face issues like long queues and long waiting times at public hospitals and it takes time to diagnose the dengue attacks. The objective of this system is to design a handy system for dengue detectors and to accurately warn the patients so that, they are being treated properly. The elements designed in this system comprised of a temperature sensor and blood dengue kit which is combined with push buttons as a tool to determine the condition of blood cells. This system used Radio-Frequency identification (RFID) access card to detect personal details. The database is directed to Windows application s on the DAS system. Results present the value of the blood level of infected dengue and body temperature in an online graph. The data can automatically send to hospitals online and access by medical officers on current situations. The system is beneficial to society as it is an essay system that can provide the user with simple and timely feedback. It would also be a significant invention to medical officers in diagnosing patients with much easier and quicker collection data using the Internet of Things (IoT).
High Frequency MOSFET Charging Circuit Using Series Parallel DC-DC Resonant Converter for Wireless Power Application
Authors: Nuawi N A A , Zin M F M , Kadir E A , Seroji M N
Published: October 2021

This paper proposes a new circuit topology of high frequency switching DC-DC Series Parallel Loaded Resonant Converter (SPLRC). The circuit is proposed to be used for a wireless power transmission application that required fast-charging operation. Most of the components used here are low-cost and commercially available in the market. Then, the purpose circuit is transformed into a different equivalent circuit that can efficiently analyze AC and DC modes. For each model, the operation for the converter is first described and explained. A full detailed circuit simulation is then carried out to find out the workability of the purpose converter. From the simulation, optimization is carried out. Here the components value is obtained. MATLAB R2018A is used for simulation purposes rather than being tested again using PSIM software to further prove the validity of the model. All the finding is explained and discussed, here, from the simulation result, it is confirmed that a high-frequency switching circuit is operated as expected.
Effect of Petroleum-Based Oil Towards Physicochemical Properties of Natural Rubber-Based Magnetorheological Elastomers
Authors: Zaki N M , Yunus N A , Yusoff M S , Ahmad F , Wahid N
Published: October 2021

This study presents an investigation of the effect of magnetorheological elastomers (MREs) using petroleum based-oil (PBO) as dispersing aids. The inhomogeneous dispersion and mobility of magnetic particles within the elastomer matrix result in poor MREs performance. Isotropic natural rubber (NR) based MREs were fabricated by homogeneously mixed with the addition of different ratios of naphthenic oil (NO) to aromatic oil (AO), whereby NO 1(100:0), NO 2 (70:30), NO 3 (50:50), and NO 4 (30:70), correspondingly. The cure characteristics, morphological, magnetic properties and thermal analyses were conducted. Based on the results, NO 1 leads the best results for microstructure observation and magnetic properties of the MREs. Meanwhile, NO 2 mixed with AO showed an improvement in curing characteristics and thermal analyses compared to other samples. In summary, the ratio of NO 1 and NO 2 is considered the preferable dispersing aids for MREs compared to NO 3 and NO 4 due to the structural compound in the oil that enhanced the characteristics of the NR-based MREs.
Design and development of student attendance system using QR-Code for UiTM Cawangan Terengganu
Authors: Hamzah S S , Bahrin U F , Yasin S N S , Eri Z D , Majid H A M A
Published: October 2021

This paper describes the development of student attendance using QR-code forUiTM Kuala Terengganu. The existing or manual attendance in Universiti Teknologi Mara Kuala Terengganu Cawangan Terengganu Kampus Kuala Terengganu (UiTMCTKKT) requires lecturer to records student attendance in attendance sheet, calculate the percentage of student attendance manually and give warning letter to the student by hand. There are several problems may occur if lecturer still using manual method to take student attendance such as lost and damaged the attendance sheet, heavy usage of papers, time limitation, and wrong calculation while calculating the attendance percentage. This project work aims to assist the lecturer in taking student attendance, to automatically calculate attendance percentage, generate warning letters to the student and lastly preventing fraudulent activities by the student. This system is developed by using the System Development Life Cycle (SDLC) waterfall model.
Potential and Opportunities of Building Information Modeling (BIM) For Housing Maintenance
Authors: Sarman A M , Jaison C , Mazlan E M , Nazeri N N
Published: October 2021

Building Information Modelling (BIM) represents an approach that aims to form and manage information over the building’s whole life cycle. BIM has been mainly adopted for commercial or large scales building projects while being mostly neglected by small or residential building. Therefore, the objectives of this study are to evaluate the readiness of BIM implementation for housing maintenance in Sabah, to access the types of priority maintenance in house maintenance, and to determine the potential benefits to apply BIM for housing maintenance. This research is focused on the participants of the construction industry in Sabah to obtain their opinions towards the opportunities and strategy of Building Information Modeling (BIM) adoption in housing maintenance. Two method was done which was a pilot survey that was analyse using SPSS and Revit modelling. The result shows that most of the industry sectors had a moderate knowledge about BIM but they agree that it should be implemented by the authority and the percentage of willingness to change from the conventional maintenance to BIM was high. The 3 highest ranked of priority maintenance is the pipes linkage, electrical faults and sanitary appliance failure. Furthermore, a modeling is created using Revit application and access of information which called the Level of Detail (LOD) regarding the items in houses is easily obtain using schedule list for the purpose of maintenance.
Construction of a Tributyrin Calibration Curve using High Performance Liquid Chromatography
Authors: Atan F , Mohamed A H , Dzulkifli N N , Zain Z M , Ahmad N M
Published: October 2021

Most of the explored research works on Triglycerides or any of the Triglycerides families was based on the profiling identification than a quantification. To quantify them, a calibration curve needs to be constructed at a certain range of concentration. In this study, the calibration curve for the shortest chain of Triglycerides namely Tributyrin was accomplished using high performance liquid ultraviolet detector with two variables parameters. The composition of mobile phase for tributyrin was found optimum using 50:50 acetonitrile: acetone while the optimum flowrate for tributyrin was 0.55 mL/min using a 20 μL injection, constant condition at 35°C and 215 nm wavelength. The calibration curve of standard tributyrin was found linear from 0.0025-0.0375 mM with the correlation coefficient (R2) of 0.986. The developed calibration curve could serve as a future platform for the quantification of TB in real samples with various matrixes such as food and serum.
V. A. Rokhlin (23 August 1919–3 December 1984), materials for the biography
Authors: Vershik A.
Published: October 2021

This publication presents some facts and documents related to the biography of the remarkable mathematician Vladimir Abramovich Rokhlin.
Vladimir Abramovich Rokhlin and algebraic topology
Authors: Buchstaber Victor
Published: October 2021

The article considers the scientific heritage of V. A. Rokhlin in algebraic topology from the point of view of the modern development of mathematics and shows the influence of his results on the development of algebraic topology up to the present. The second part of the article contains new results with fairly detailed sketches of their proofs. There we introduce the notion of partially framed manifolds, which naturally arise in the study of the characteristic classes of vector bundles over the loop space

Ω
S
U
(
2
)
=
Ω
S
P
(
1
)

\Omega SU(2)=\Omega SP(1)

. We obtain theorems on the divisibility of the signature of such manifolds as a result of calculations of characteristic classes with values in complex and quaternionic cobordism.
Circular orders, ultra-homogeneous order structures, and their automorphism groups
Authors: Glasner Eli , Megrelishvili Michael
Published: October 2021

We study topological groups

G
G

for which either the universal minimal

G
G

-system

M
(
G
)

M(G)

or the universal irreducible affine

G
G

-system

I

A
(
G
)

I\!A(G)

is tame. We call such groups “intrinsically tame” and “convexly intrinsically tame”, respectively. These notions, which were introduced in [Ergodic theory and dynamical systems in their interactions with arithmetics and combinatorics, Springer, Cham, 2018, pp. 351–392], are generalized versions of extreme amenability and amenability, respectively. When

M
(
G
)

M(G)

, as a

G
G

-system, admits a circular order we say that

G
G

is intrinsically circularly ordered. This implies that

G
G

is intrinsically tame.

We show that given a circularly ordered set

X
∘

X_\circ

, any subgroup

G
≤

A

u
t

(

X
∘

)

G \leq {\mathrm {A}ut}\,(X_\circ )

whose action on

X
∘

X_\circ

is ultrahomogeneous, when equipped with the topology

τ
p

\tau _p

of pointwise convergence, is intrinsically circularly ordered. This result is a “circular” analog of Pestov’s result about the extreme amenability of ultrahomogeneous actions on linearly ordered sets by linear order preserving transformations. We also describe, for such groups

G
G

, the dynamics of the system

M
(
G
)

M(G)

, show that it is extremely proximal (whence

M
(
G
)

M(G)

coincides with the universal strongly proximal

G
G

-system), and deduce that the group

G
G

must contain a non-abelian free group.

In the case where

X
X

is countable, the corresponding Polish group of circular automorphisms

G
=

A

u
t

(

X
o

)

G={\mathrm {A}ut}\,(X_o)

admits a concrete description. Using the Kechris–Pestov–Todorcevic construction we show that

M
(
G
)
=

S
p
l
i
t

(

T

;

Q

∘

)

M(G)={\mathrm {Split}}(\mathbb {T};\mathbb {Q}_{\circ })

, a circularly ordered compact metric space (in fact, a Cantor set) obtained by splitting the rational points on the circle

T

\mathbb {T}

. We show also that

G
=

A

u
t

(

Q

∘

)

G={\mathrm {A}ut}\,(\mathbb {Q}_{\circ })

is Roelcke precompact, satisfies Kazhdan’s property

T
T

(using results of Evans–Tsankov), and has the automatic continuity property (using results of Rosendal–Solecki).
A user’s guide to basic knot and link theory
Authors: Skopenkov A.
Published: October 2021

We define simple invariants of knots or links (linking number, Arf-Casson invariants and Alexander-Conway polynomials) motivated by interesting results whose statements are accessible to a non-specialist or a student. The simplest invariants naturally appear in an attempt to unknot a knot or unlink a link. Then we present certain ‘skein’ recursive relations for the simplest invariants, which allow us to introduce stronger invariants. We state the Vassiliev–Kontsevich theorem in a way convenient for calculating the invariants themselves, not only the dimension of the space of the invariants. No prerequisites are required; we give rigorous definitions of the main notions in a way not obstructing intuitive understanding.
Local dynamics of non-invertible maps near normal surface singularities
Authors: Gignac William , Ruggiero Matteo
Published: October 2021

We study the problem of finding algebraically stable models for non-invertible holomorphic fixed point germs

f
:
(
X
,

x
0

)
→
(
X
,

x
0

)

f\colon (X,x_0)\to (X,x_0)

, where

X
X

is a complex surface having

x
0

x_0

as a normal singularity. We prove that as long as

x
0

x_0

is not a cusp singularity of

X
X

, then it is possible to find arbitrarily high modifications

π
:

X
π

→
(
X
,

x
0

)

\pi \colon X_\pi \to (X,x_0)

such that the dynamics of

f
f

(or more precisely of

f
N

f^N

for

N
N

big enough) on

X
π

X_\pi

is algebraically stable. This result is proved by understanding the dynamics induced by

f
f

on a space of valuations associated to

X
X

; in fact, we are able to give a strong classification of all the possible dynamical behaviors of

f
f

on this valuation space. We also deduce a precise description of the behavior of the sequence of attraction rates for the iterates of

f
f

. Finally, we prove that in this setting the first dynamical degree is always a quadratic integer.
Relationship between depression and olfactory sensory function: a review
Authors: Athanassi Anna , Dorado Doncel Romane , Bath Kevin G , Mandairon Nathalie
Published: October 2021

Links between olfactory sensory function and effect have been well established. A robust literature exists in both humans and animals showing that disrupting olfaction sensory function can elicit disordered mood state, including serve as a model of depression. Despite this, considerably less is known regarding the directionality and neural basis of this relationship, e.g. whether disruptions in sensory function precede and contribute to altered mood or if altered mood state precipitates changes in olfactory perception. Further, the neural basis of altered olfactory function in depression remains unclear. In conjunction with clinical studies, animal models represent a valuable tool to understand the relationship between altered mood and olfactory sensory function. Here, we review the relevant literature assessing olfactory performance in depression in humans and in rodent models of depressive-like behavioral states. Rodents allow for detailed characterization of alterations in olfactory perception, manipulation of experiential events that elicit depressive-like phenotypes, and allow for interrogation of potential predictive markers of disease and the cellular basis of olfactory impairments associated with depressive-like phenotypes. We synthesize these findings to identify paths forward to investigate and understand the complex interplay between depression and olfactory sensory function.
Development and Validation of a Novel LC–MS/MS Method for the Quantitation of 19 Fingerprint Phytochemicals in Salvia Species: A Chemometric Approach
Authors: Yilmaz Mustafa Abdullah , Ertas Abdulselam , Yener Ismail , Olmez Ozge Tokul , Firat Mehmet , Temel Hamdi , Ozturk Mehmet , Kolak Ufuk
Published: October 2021

Being traditionally utilized mainly as appetizers and herbal teas as well as used to ease abdominal pains, colds and gastrointestinal issues, the genus Salvia L. has gained significant consideration owing to its remarkable phytochemicals and industrial importance. The present study aimed to develop and validate an LC–MS/MS method for the qualitative and quantitative investigation of 19 fingerprint phytochemicals in six endemic Salvia species. The validation parameters of the developed LC–MS/MS method were repeatability (intermediate precision), recovery (accuracy), limits of detection and quantification, linearity and uncertainty (U% at 95% confidence level (k = 2)). Reversed-phase HPLC separation and mass spectrometry parameters were optimized for each analyte. Ethanol extracts of the studied Salvia species collected in three consecutive years were screened for their fingerprint phytochemicals by using the developed and validated LC–MS/MS method. Moreover, studied Salvia species were subjected to multivariate analysis such as principal component analysis techniques to demonstrate the variabilities in phytochemical contents by years and parts of the samples. Roots, flowers, leaves, branches and whole plant of the Salvia species collected in 2015, 2016 and 2017 were used for the analyses. It was observed that the roots and branches of Salvia species were similar in terms of their salvianolic acid A, caffeic acid, and 6,7-dehydroroyleanone components. Accordingly, apigenin, rosmarinic acid, luteolin 7-O-glucoside, caffeic acid, salvianolic acid B, and 6,7-dehydroroyleanone were notable phytochemicals that were present in the studied Salvia species.
Housing Cost Burden and Health Decline Among Low- and Moderate-Income Older Renters
Authors: Jenkins Morales Meghan , Robert Stephanie A
Published: October 2021

Objective

To examine the association between housing cost burden (HCB) and health decline among low- and moderate-income older renters in the United States.

Method

Baseline data include low- and moderate-income community-dwelling older renters (N = 1,064) from the nationally representative 2015 National Health and Aging Trends Study. HCB was defined as the percentage of monthly income spent on rent, categorized as “no HCB” (<30%), “moderate HCB” (30%–49%), and “severe HCB” (≥50%). We used weighted logistic regression models to estimate whether HCB status in 2015 and change in HCB between 2015 and 2017 were associated with self-rated health decline and developing a new limitation related to activities of daily living (ADL) or instrumental activities of daily living (IADL) between 2015 and 2017.

Results

Older renters with severe HCB in 2015 were the most likely to develop a new ADL/IADL limitation (63.4%) over time (p < .05). The association between HCB status in 2015 and self-rated health decline was not statistically significant, but older renters with persistent HCB had 1.64 times greater odds of self-rated health decline (p < .05) and 2.01 times greater odds of developing a new ADL/IADL limitation (p < .01), compared to older renters with no HCB at baseline and follow-up.

Discussion

Even in the short term, HCB contributes to health decline in later life. Efforts to promote equity and healthy aging in the community must consider how to best address housing affordability among the growing population of older renters.
Severe Acute Respiratory Syndrome Coronavirus 2 Seroassay Performance and Optimization in a Population With High Background Reactivity in Mali
Authors: Woodford John , Sagara Issaka , Dicko Alassane , Zeguime Amatigue , Doucoure M’Bouye , Kwan Jennifer , Zaidi Irfan , Doritchamou Justin , Snow-Smith Maryonne , Alani Nada , Renn Jonathan , Kosik Ivan , Holly Jaroslav , Yewdell Jonathan , Esposito Dominic , Sadtler Kaitlyn , Duffy Patrick
Published: October 2021

Background

False positivity may hinder the utility of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serological tests in sub-Saharan Africa.

Methods

From 312 Malian samples collected before 2020, we measured antibodies to the commonly tested SARS-CoV-2 antigens and 4 other betacoronaviruses by enzyme-linked immunosorbent assay (ELISA). In a subset of samples, we assessed antibodies to a panel of Plasmodium falciparum antigens by suspension bead array and functional antiviral activity by SARS-CoV-2 pseudovirus neutralization assay. We then evaluated the performance of an ELISA using SARS-CoV-2 spike protein and receptor-binding domain developed in the United States using Malian positive and negative control samples. To optimize test performance, we compared single- and 2-antigen approaches using existing assay cutoffs and population-specific cutoffs.

Results

Background reactivity to SARS-CoV-2 antigens was common in prepandemic Malian samples. The SARS-CoV-2 reactivity varied between communities, increased with age, and correlated negligibly/weakly with other betacoronavirus and P falciparum antibodies. No prepandemic samples demonstrated functional activity. Regardless of the cutoffs applied, test specificity improved using a 2-antigen approach. Test performance was optimal using a 2-antigen assay with population-specific cutoffs (sensitivity, 73.9% [95% confidence interval {CI}, 51.6–89.8]; specificity, 99.4% [95% CI, 97.7–99.9]).

Conclusions

We have addressed the problem of SARS-CoV-2 seroassay performance in Africa by using a 2-antigen assay with cutoffs defined by performance in the target population.
No Consistent Evidence of Decreased Exposure to Varicella-Zoster Virus Among Older Adults in Countries with Universal Varicella Vaccination
Authors: Carryn Stephane , Cheuvart Brigitte , Povey Michael , Dagnew Alemnew F , Harpaz Rafael , van der Most Robbert , Casabona Giacomo
Published: October 2021

Background

Universal varicella vaccination might reduce opportunities for varicella-zoster virus (VZV) exposure and protective immunological boosting, thus increasing herpes zoster incidence in latently infected adults. We assessed humoral and cell-mediated immunity (CMI), as markers of VZV exposure, in adults aged ≥50 years.

Methods

We repurposed data from placebo recipients in a large multinational clinical trial (ZOE-50). Countries were clustered based on their varicella vaccination program characteristics, as having high, moderate, or low VZV circulation. Anti-VZV antibody geometric mean concentrations, median frequencies of VZV-specific CD4 T cells, and percentages of individuals with increases in VZV-specific CD4 T-cell frequencies were compared across countries and clusters. Sensitivity analyses using a variable number of time points and different thresholds were performed for CMI data.

Results

VZV-specific humoral immunity from 17 countries (12 high, 2 moderate, 3 low circulation) varied significantly between countries (P < .0001) but not by VZV circulation. No significant differences were identified in VZV-specific CMI between participants from 2 high versus 1 low circulation country. In 3/5 sensitivity analyses, increases in CMI were more frequent in high VZV circulation countries (.03 ≤ P < .05).

Conclusions

We found no consistent evidence of reduced VZV exposure among older adults in countries with universal varicella vaccination.

Clinical Trials Registration

NCT01165177.
What Are We Actually Talking About? Conceptualizing Data as a Governable Object in Overlapping Jurisdictions
Authors: Obendiek Anke Sophia
Published: October 2021

Data form an increasingly essential element of contemporary politics, as both public and private actors extend claims of their legitimate control in diverse areas including health, security, and trade. This paper investigates data governance as a site of fundamental normative and political ordering processes that unfold in light of ever-increasing inter- and transnational linkages. Drawing on the concept of jurisdictional conflicts, the paper traces the evolution of data governance in three cases of transatlantic conflicts as diverging definitional claims over data. The paper argues that these conflicts reveal varying conceptualizations of data linked to four distinct visions of the social world. First, a conceptualization of data as an individual rights issue links human rights with the promotion of sovereignty to a vision of data governance as local liberalism. Second, proponents of a security partnership promote global security cooperation based on the conceptualization of data as a neutral instrument. Third, a conceptualization of data as an economic resource is linked to a vision of the digital economy that endorses progress and innovation with limited regulation. Fourth, a conceptualization of data as a collective resource links the values of universal rights and global rules to a vision of global protection.
Temporally informed random forests for suicide risk prediction
Authors: Bayramli Ilkin , Castro Victor , Barak-Corren Yuval , Madsen Emily M , Nock Matthew K , Smoller Jordan W , Reis Ben Y
Published: October 2021

Objective

Suicide is one of the leading causes of death worldwide, yet clinicians find it difficult to reliably identify individuals at high risk for suicide. Algorithmic approaches for suicide risk detection have been developed in recent years, mostly based on data from electronic health records (EHRs). Significant room for improvement remains in the way these models take advantage of temporal information to improve predictions.

Materials and Methods

We propose a temporally enhanced variant of the random forest (RF) model—Omni-Temporal Balanced Random Forests (OT-BRFs)—that incorporates temporal information in every tree within the forest. We develop and validate this model using longitudinal EHRs and clinician notes from the Mass General Brigham Health System recorded between 1998 and 2018, and compare its performance to a baseline Naive Bayes Classifier and 2 standard versions of balanced RFs.

Results

Temporal variables were found to be associated with suicide risk: Elevated suicide risk was observed in individuals with a higher total number of visits as well as those with a low rate of visits over time, while lower suicide risk was observed in individuals with a longer period of EHR coverage. RF models were more accurate than Naive Bayesian classifiers at predicting suicide risk in advance (area under the receiver operating curve = 0.824 vs. 0.754, respectively). The proposed OT-BRF model performed best among all RF approaches, yielding a sensitivity of 0.339 at 95% specificity, compared to 0.290 and 0.286 for the other 2 RF models. Temporal variables were assigned high importance by the models that incorporated them.

Discussion

We demonstrate that temporal variables have an important role to play in suicide risk detection and that requiring their inclusion in all RF trees leads to increased predictive performance. Integrating temporal information into risk prediction models helps the models interpret patient data in temporal context, improving predictive performance.