bluuebunny/crossref_metadata_2025_split huggingface dataset:
Carbon-chain Chemistry versus Complex-organic-molecule Chemistry in Envelopes around Three Low-mass Young Stellar Objects in the Perseus Region
Authors: Taniguchi Kotomi , Majumdar Liton , Takakuwa Shigehisa , Saito Masao , Lis Dariusz C. , Goldsmith Paul F. , Herbst Eric 
Published: April 2021

Abstract
We have analyzed ALMA Cycle 5 data in Band 4 toward three low-mass young stellar objects, IRAS 03235+3004 (hereafter IRAS 03235), IRAS 03245+3002 (IRAS 03245), and IRAS 03271+3013 (IRAS 03271), in the Perseus region. The HC3N (J = 16–15; E
up/k = 59.4 K) line has been detected in all of the target sources, while four CH3OH lines (E
up/k = 15.4–36.3 K) have been detected only in IRAS 03245. Sizes of the HC3N distributions (∼2930–3230 au) in IRAS 03235 and IRAS 03245 are similar to those of the carbon-chain species in the warm carbon-chain chemistry (WCCC) source L1527. The size of the CH3OH emission in IRAS 03245 is ∼1760 au, which is slightly smaller than that of HC3N in this source. We compare the CH3OH/HC3N abundance ratios observed in these sources with predictions of chemical models. We confirm that the observed ratio in IRAS 03245 agrees with the modeled values at temperatures around 30–35 K, which supports the HC3N formation by the WCCC mechanism. In this temperature range, CH3OH does not thermally desorb from dust grains. Nonthermal desorption mechanisms or gas-phase formation of CH3OH seem to work efficiently around IRAS 03245. The fact that IRAS 03245 has the highest bolometric luminosity among the target sources seems to support these mechanisms, in particular the nonthermal desorption mechanisms.
Anomalous Proton Velocity Diffusion by Quasi-monochromatic Kinetic Alfvén Waves
Authors: Choi Cheong R. , Woo M.-H. , Yoon P. H. , Lee D.-Y. , Park K. S. 
Published: April 2021

Abstract
The anomalous diffusion of resonant protons in parallel and perpendicular velocity space by kinetic Alfvén waves is discussed. The velocity diffusion coefficient is calculated by employing an autocorrelation function for proton trajectories. It is found that for protons resonant with the waves, the perpendicular diffusion coefficient decays away for a sufficiently long time, but parallel diffusion monotonically increases in time until it saturates at a certain level. This result indicates that a portion of resonant protons can undergo anomalous diffusion along the background magnetic field even if the intensity of the kinetic Alfvén wave is sufficiently low. The present findings imply that under suitable conditions, astrophysical charged-particle acceleration can take place in the parallel direction.
Dalek: A Deep Learning Emulator for TARDIS
Authors: Kerzendorf Wolfgang E. , Vogl Christian , Buchner Johannes , Contardo Gabriella , Williamson Marc , van der Smagt Patrick 
Published: April 2021

Abstract
Supernova spectral time series contain a wealth of information about the progenitor and explosion process of these energetic events. The modeling of these data requires the exploration of very high dimensional posterior probabilities with expensive radiative transfer codes. Even modest parameterizations of supernovae contain more than 10 parameters and a detailed exploration demands at least several million function evaluations. Physically realistic models require at least tens of CPU minutes per evaluation putting a detailed reconstruction of the explosion out of reach of traditional methodology. The advent of widely available libraries for the training of neural networks combined with their ability to approximate almost arbitrary functions with high precision allows for a new approach to this problem. Instead of evaluating the radiative transfer model itself, one can build a neural network proxy trained on the simulations but evaluating orders of magnitude faster. Such a framework is called an emulator or surrogate model. In this work, we present an emulator for the tardis supernova radiative transfer code applied to Type Ia supernova spectra. We show that we can train an emulator for this problem given a modest training set of 100,000 spectra (easily calculable on modern supercomputers). The results show an accuracy on the percent level (that are dominated by the Monte Carlo nature of tardis and not the emulator) with a speedup of several orders of magnitude. This method has a much broader set of applications and is not limited to the presented problem.
The Role of Strong Gravity and the Nuclear Equation of State on Neutron-star Common-envelope Accretion
Authors: Holgado A. Miguel , Silva Hector O. , Ricker Paul M. , Yunes Nicolás 
Published: April 2021

Abstract
Common-envelope evolution is important in the formation of neutron star binaries within the isolated binary formation channel. As a neutron star inspirals within the envelope of a primary massive star, it accretes and spins up. Because neutron stars are in the strong-gravity regime, they have a substantial relativistic mass deficit, i.e., their gravitational mass is less than their baryonic mass. This effect causes some fraction of the accreted baryonic mass to convert into neutron star binding energy. The relativistic mass deficit also depends on the nuclear equation of state, since more compact neutron stars will have larger binding energies. We model the mass growth and spin-up of neutron stars inspiraling within common-envelope environments and quantify how different initial binary conditions and hadronic equations of state affect the post-common-envelope neutron star’s mass and spin. From these models, we find that neutron star mass growth is suppressed by ≈15%–30%. We also find that for a given amount of accreted baryonic mass, more compact neutron stars will spin-up faster while gaining less gravitational mass, and vice versa. This work demonstrates that a neutron star’s strong gravity and nuclear microphysics plays a role in neutron-star-common-envelope evolution, in addition to the macroscopic astrophysics of the envelope. Strong gravity and the nuclear equation of state may thus affect both the population properties of neutron star binaries and the cosmic double neutron star merger rate.
Ina Lunar Irregular Mare Patch Mission Concepts: Distinguishing between Ancient and Modern Volcanism Models
Authors: Qiao Le , Head James W. , Wilson Lionel , Ling Zongcheng 
Published: April 2021

Abstract
The Ina irregular mare patch, an ∼2 × 3 km summit depression on an ancient ∼22 km diameter shield volcano, displays two very enigmatic units: (1) dozens of dark convex-upward mounds and (2) a very rough, optically immature floor unit with very sharp morphologic contacts between the two. Controversy surrounds the age interpretation of Ina; superposed impact crater size–frequency distributions (CSFDs) suggest an age of ∼33 Ma, consistent with the presence of sharp contacts between the units and indicating that mare volcanism continues to today. Models of the terminal stages of volcano summit pit crater activity suggest an age coincident with the building of the shield, ∼3.5 Ga; these models interpret the CSFD age and sharp contacts to be due to an extremely porous lava lake floor and extrusion and solidification of magmatic foams. We present robotic–human exploration mission concepts designed to resolve this critical issue for lunar thermal evolution.
Forest Product Industry and Engineered Wood Products: The Nigerian Experience
Authors: Ekundayo O.O. , Arum C. , Owoyemi J.M. 
Published: April 2021

The forest product industry in Nigeria is barely surviving rather than thriving. Faced with a lot of challenges, the industry has witnessed the closure of many wood processing industries while a few are operating at low capacity. This paper examines engineered wood products and the outlook on wood and wood products in Nigeria. It discusses some of the challenges that have inhibited the growth of the industry and provides recommendations for reinventing the industry through development of modern value-added wood products for sustainable building construction.
Keywords: Collaboration; Engineered wood products; Forestry product industry; Glulam; Sustainability.
Effects of heat stress on the hepatic transcriptome of yellow-feathered chickens
Authors: Zhang Q. , Lu Y.Q. , Cao Z.W. , Yang Y.Z. 
Published: April 2021

Heat stress is one of the main environmental factors that hamper the efficiency of poultry production. Heat stress is known to be less harmful to yellow-feathered chickens (YFC) than to commercial broilers, especially in its effect on the relative weight of organs. The transcriptome was used to examine the gene expression profile of the livers of YFC that were exposed to heat stress. Mean liver weight (HW) and the hepatic weight index (HWI) of birds in the heat stress group did not differ significantly from those of the control group. A total of 596 genes were differentially expressed in the liver in response to heat stress. The enrichment results of differentially expressed genes (DEG) showed that many of these genes were related to the Fanconi anaemia pathway and that the cell cycle pathway was modulated. Thus, it can be concluded that these genes might be involved in improving the stability of the YFC liver genome and controlling the physiological response to heat stress.
Keywords:, heat stress, liver, transcriptome, yellow-feathered chickens
Reusing intravaginal progesterone releasing devices for oestrous synchoronization in ewes
Authors: Rodríguez-Sánchez Y.I. , Sánchez-Torres M.T. , Cordero-Mora J.L. , Figueroa-Velasco J.L. , Cortés-Zorrilla J. , Martínez-Aispuro J.A. , Cardenas-León M. 
Published: April 2021

In this study, the second use of an intravaginal progesterone-releasing device or controlled intravaginal drug release device (CIDR) was evaluated. After a first use of 11 days, the CIDR was again used for either nine or 12 days with 200 or 300 IU equine chorionic gonadotrophin (eCG) being injected on its removal. Sixty-four ewes were randomly distributed to four treatments (n=16/group): CIDR9+eCG200, CIDR9+eCG300, CIDR12+eCG200, and CIDR12+eCG300. The eCG was administered intramuscularly on withdrawal of the device. Thus, the experiment was a completely randomized design with a 2×2 factorial arrangement of treatments. Oestrus presentation did not differ between treatments (P =0.29). However, with the dose of 200 IU of eCG, oestrus presentation tended to increase (P =0.08). The onset and duration of oestrus, percentage of gestation, and return to oestrus did not differ between treatments (P >0.05). Progesterone concentration in serum was greater (P < 0.05) in ewes treated with CIDR12+eCG300. Prolificacy was greatest (1.44) with the CIDR12+eCG300 treatment and was different (P = 0.001) from the treatments CIDR9+eCG200 (1.21) and CIDR9+eCG300 (1.20), but not from the CIDR12+eCG200 treated ewes (1.31). The CIDR12+eCG300 treatement produced the highest percentage of twin births (45.8%) (P =0.001). Leaving the device in place for 12 days increased (P =0.001) the incidence of twin births. Use of the CIDR for a second time synchronized oestrus in ewes successfully with better fertility being obtained when the device was left in place for 12 days, and 300 IU of eCG was injected on its removal.
Key words: gonadotropin, progesterone device, synchronization
Linkages between catchment characteristics and river water chemistry at the locality scale in the Ikpoba River, Southern Nigeria
Authors: Edokpa D.A. , Obieroma J.O. 
Published: April 2021

This study explored the linkages between catchment characteristics (topography, land cover, soil and geology), average water chemistry (pH, calcium, magnesium, sulphate, nitrate, ammonium, orthophosphate, iron, zinc and lead) and rainfall in the Ikpoba River catchment, southern Nigeria, using statistical and locality-based GIS analyses. The results show that sites with high rainfall and percentage cover of arable and sand-gravel-clay lithologies were characterized by high acidity. There were strong links between average nutrient (𝑃𝑂43−-P, 𝑁𝐻4+-N and 𝑁𝑂3−-N) concentrations and diffuse agricultural sources in the catchment. Rainfall was strongly related to 𝑆𝑂42−, 𝑃𝑂43−-P and 𝑁𝐻4+-N suggesting that atmospheric deposition may influence their riverine concentrations. Results also suggest that decomposition of organic matter from forest stands was a significant driver of nutrient concentrations. Although metals (Fe2+ and Zn2+) were positively related to bedrock geology of sand-gravel-clay, there was no clear link between Pb2+ and the catchment characteristics investigated. Wetlands was found to be attenuating river water chemistry especially 𝑆𝑂42−, 𝑃𝑂43−-P and 𝑁𝐻4+-N concentrations. To underpin current environmental protection strategies, there is need to integrate a GIS-based analysis approach with monitoring data to fully identify the variability patterns in river water chemistry dynamics at local and multiple scales of water resource management in Nigeria.
Key words: river catchment, water quality, metals, nutrients, GIS.
Seasonal changes in the abundance of benthic macroinvertebrates & physico-chemical condition of Moussa Stream Bida, Nigeria
Authors: Mohammed Y.M. , Arimoro F.O. , Ayanwale A.V. , Adama B.S. , Keke U.N. , Auta Y.I. , Umar B.I. 
Published: April 2021

Seasonal changes in the abundance of benthic macroinvertebrates and physico-chemical condition of Moussa Stream, Bida Nigeria, were studied monthly from January to August 2017. Macroinvertebrates were sampled using modified kick sampling techniques. Three different sampling stations were selected along the course of the Stream. The results from the stream showed that water temperature (24.9-27.50C), Depth (14.7-45.8cm), Flow velocity (0.14-0.23m/s), Biochemical oxygen demand (2.0-7.0mg/L), pH (6.33-8.6), Conductivity (20-63μ/cm), Alkalinity (8-30mg/L), Turbidity (61-285NTU), Nitrate (0.87-3.85mg/L) and Phosphate (0.31-1.01mg/L) were within the maximum permissible limit (WHO, SON) except Dissolved oxygen (3.1-10mg/L). Most of the parameters investigated with the exception of depth and flow velocity showed no significant difference (p>0.05) among all the sampling stations. Temperature, depth and flow velocity showed no significant differences with season. pH, DO, BOD5, Turbidity, Conductivity, Alkalinity, Nitrate, and Phosphate were significantly higher during wet season. A total of 471 individuals from 30 species and 20 families of invertebrates were recorded. The overall macroinvertebrates recorded from station 1, 2 and 3 were 166(35.24%), 149(31.63%) and 156(33.12%). Overall, there was significant difference (P<0.05) in number of individuals among the sampling stations. The abundance according to the Orders revealed that Coleopterans, Odonata and Hemipterans were the most common groups encountered. Ephemeroptera Diptera, Mollusca and Oligochaeta were sparingly found in all stations. The percentage and total number of individuals of macroinvertebrates recorded during the study period shows 67.09% (316 individuals) in dry season and the remaining 32.90% (155 individuals) were recorded in rainy season. CCA result correlated positively between species abundances and measured environmental variables. Low density of pollution sensitive macro invertebrates groups and the deteriorating water quality were implications of pollution stress caused by anthropogenic activities.
Key words: seasonal changes, macroinvertebrates, stream, Bida.
Estimation of gillnet selectivity of Coptodon zillii in Asejire Lake, Oyo State, Nigeria
Authors: Ajagbe S.O. , Odulate D.O. , Idowu A.A. , Ajagbe R.O. , Ariwoola O.S. , Abdulazeez F.I. , Ojubolamo M.T. , Olomola A.O. , Oyekan O.O. , Ganiyu O.A. 
Published: April 2021

Gillnet selectivity of Coptodon zillii was estimated in this study to determine the appropriate mesh size for the exploitation of the fish in Asejire dam. Holt’s indirect method of estimation was used to estimate gillnet selectivity of C. zillii in Asejire dam. Three mesh sizes 50.8mm, 63.5mm and 76.2mm were used for the estimation. The result shows that these mesh sizes caught C. zillii that were significantly different in sizes and abundant (P < 0.05). The 63.5 mm mesh size of gillnet was the most efficient; it caught 150 C. zillii with length range of 13 – 22 cm. Also, 50.8 mm mesh size caught137 C. zillii with length range of 11 – 18 cm. Likewise, 76.2 mm mesh size caught 57 C. zillii with length range 16 – 24 cm. The optimum length of 50.8 mm mesh size was 14.78 cm, 63.5 mm was 18.48 cm and 76.2 mm was 22.17 cm. Mesh size of 63.5mm is recommended as the appropriate mesh size for the exploitation of C. zillii in Asejire dam for the sustainability of the fish. This is done to prevent both recruitment and growth overfishing of C. zillii in Asejire dam.
Key words: optimum length; exploitation; selection; sexual maturity; recruitment overfishing, growth overfishing
Spatio-temporal variation level of heavy metals in surface water and sediment in Tagwai Lake, Minna, Nigeria
Authors: Chukwuemeka V.I. , Jimoh E.A. , Olajide K.O. , Auta Y.I. , Auta H.S. , Erhabor O.F. 
Published: April 2021

The high contamination of aquatic systems with toxic heavy metals is of major concern since the elements are not biodegradable. Heavy metals often get into the water through runoff from farmlands and dumping of effluents from industries into the water bodies. The toxicity of these heavy metals can cause harmful and even lethal effects on the human health. The objective of this study was to investigate the level of Pb, Cu, Mn, and Fe in both surface water and sediment of Tagwai Lake. Atomic Absorption Spectrometry investigation was carried out on the collected and digested water and sediment samples to determine the extent of these heavy metals contamination in the water. The results showed that the average concentration of heavy metals ranked in the following order: Pb>Mn>Cu>Fe with higher concentration in sediment compared to the water. The correspondence of the mean concentrations of heavy metals in water and sediment of the Tagwai Lake with the WHO standard suggests that the mean concentration of Pb, Cu, and Fe lies within the standard range while Mn exceeds the standard range in both the water and sediments. We therefore advocate regular surveillance as a tool for monitoring impacts of anthropogenic activities in the lake to ensure safety of the general populace who depend on it for their livelihood.
Keywords: spatio-temporal, heavy metals, sediments, Tagwai Lake
Acute toxicity of Jatropha curcas (barbados nut) latex extracts to Oreochromis niloticus juveniles
Authors: Usman M , Umaru J.A , Kigbu A.A 
Published: April 2021

The effects of the latex extract of Jatropha curcas on mortality rate, opercular ventilation rate and some behavioural responses of Oreochromis niloticus juveniles were investigated under laboratory conditions over a 96 hours exposure period. Juveniles of Oreochromis niloticus (Trewavas) were exposed in plastic aquaria to 0.00mg.l-1 (control), 10mg.l-1, 15mg.l-1, 20mg.l-1, 25mg.l-1 and 30mg.l-1. Their opercular beats per minute, tail fin beats per minute, mortality and probit kill were determined. Symptoms of toxicosis observed include agitated swimming, loss of equilibrium, air gulping, periods of quiescence and death. Within 24 hours the opercular ventilation beats and tail fin beats of the exposed fish were significantly higher than in control fish (p<0.05). At 72 hours and 96 hours the opercular and tailfin beats in the control fish were significantly higher (P<0.05) than the exposed fish. The 96 hours LC50 was determined as 5.23 ml/l. Include significance of this study to conclude abstract.
Key words: acute toxicity, Jatropha curcas latex extract, Oreochromis niloticus, haematological parameters.
Water renewal in static systems: Impacts on productivity and survival in Clarias gariepinus (Burchell, 1822)
Authors: Opute P.A , Odion G.F 
Published: April 2021

The impact of water renewal in a static system on the growth and survival of Clarias gariepinus fingerlings was investigated under six different treatments, namely: T1 (daily water renewal), T3 (three days water renewal), T5 (five days water renewal), T7 (seven days water renewal), T9 (nine days water renewal) and T14 (fourteen days water renewal). Results showed that growth performance and survival was significantly (P< 0.05) affected by the water renewal frequencies. After six weeks, weight gain, daily weight gain, specific growth rate, final body weight, was significantly higher in T5 (P< 0.001). Likewise, survival in T5 was significantly higher compared to other groups (P< 0.001). For all evaluated parameters, T14 had the least performance. Slow response to feeding, slow movement and hanging on the water surface was observed in T9 and T14. Daily water renewal tank had significantly (p < 0.05) higher dissolved oxygen (04.52 mg L-1) while electrical conductivity (800.00 μScm-1) was significantly higher in T14 (P< 0.001). From the result, the growth and survival of the catfish fingerlings in T5 are superior to other renewal regimes. Therefore, for optimum growth and productivity of African catfish fingerlings reared in a static system, it is recommended that water renewal be performed every five days.
Key words: Clarias gariepinus, water renewal, weight gain, water quality, behaviour, feed conversion ratio, specific growth rate
Investigation of plasminogen activator inhibitor-1 (PAI-1) levels in patients diagnosed with polycystic ovary syndrome
Authors: Bağlı İhsan , Küçük Mert 
Published: April 2021

Objective:The aim of this study was to investigate the plasma levels of plasminogen activator inhibitor -1 (PAI-1) known as a potent inhibitor of fibrinolysis in women with polycystic ovary syndrome (PCOS) and compare with health controls.
Methods: Forty women with PCOS diagnosed using 2003 revised Rotterdam criteria and 40 healthy women who attended to Adnan Menderes University Department of Obstetrics and Gynecology between July-October 2013 were recruited to this prospective study. We noted all participant’s demographic features, calculated body mass index (BMI), waist hip ratio (WHR), and measured blood pressures. We performed modified Ferriman-Gallwey Score (mFGS) and calculated Luteinizing hormone (LH)/Follicle stimulating hormone (FSH) ratio and homeostatic model assessment insulin resistance (HOMA-IR) of participants. PAI-1 levels were measured by using the Human PAI-1 Elisa test. We used the student T test and Mann-Whitney U test as statistical methods. A p-value less than 0.05 was considered statistically significant.
Results: We found PAI-1 levels, fasting insulin levels, HOMA-IR index, BMI significantly higher in the PCOS group compared with the control group. Mean age of the participants was found lower in the PCOS group. Between the groups we found no statistically significant differences in terms of the LH/FSH ratio, fasting glucose, dehydroepiandrosterone and testosterone levels.