bluuebunny/crossref_metadata_2025 huggingface dataset:
Visualizing the effects of plasma-generated H atoms in situ in a transmission electron microscope
Authors: Maurice Jean-Luc , Bulkin Pavel , Ngo Éric , Wang Weixi , Foldyna Martin , Florea Ileana , Roca i Cabarrocas Pere , Béjaud Romuald , Hardouin Duparc Olivier
Published: February 2022

The radicals and atoms generated by a plasma have the effect, among others, of changing the surface energies of materials, which allows one to prepare nano-objects that would not stabilise in other conditions. This is the case of the Sn catalysed silicon nanowires (NWs) we present in this paper: without plasma, the liquid Sn at the top of NWs is unstable (because Sn naturally wets the Si) so that no growth is allowed, while in presence of the H atoms generated by the plasma, the balance of surface energies is drastically changed; the Sn droplet stabilises and can be used efficiently by the vapour-liquid-solid (VLS) mechanism of growth. Thus, if one wants to study the growth mechanisms of such NWs in situ in the transmission electron microscope (TEM), one has to adapt a plasma system on the TEM. This is precisely what was done at École polytechnique on the NanoMAX environmental TEM. The paper reports on the plasma effects, on the catalyst and on NW growth, recorded in situ in real time, at atomic resolution. The results are discussed in the light of density functional calculations of bare and hydrogenated Si surface energies.
Gastrointestinale Blutungen bei Patienten mit linksventrikulärem Assist Device
Authors: Andersen Nils
Published: February 2022

Aufgrund der stetig wachsenden Anzahl von Patienten mit fortgeschrittener und terminaler Herzinsuffizienz und der begrenzten Verfügbarkeit von Spenderorganen nimmt die breite Verwendung von LVADs bei diesem Krankheitsbild zu. In den letzten 30 Jahren hat sich die mechanische Kreislaufunterstützung von einer experimentellen Therapieform zu einer effizienten und anerkannten Behandlung der chronischen Herzinsuffizienz entwickelt. Die neueren Systeme führten zu einer Senkung der Komplikationsraten bei zunehmender Überlebenswahrscheinlichkeit, klinischer Leistung und erhöhter Lebensqualität. Trotzdem bleibt die gastrointestinale Blutung eine der häufigsten Komplikationen bei dieser Therapieform. Dies ist durch mehrere Studien gut belegt.
Umbilical Cord Teratoma Presenting as Ruptured Omphalocele
Authors: Doktor Fabian , Gosemann Jan-Hendrik , Zimmermann Peter , Siekmeyer Manuela , Stepan Holger , Lacher Martin
Published: February 2022

Congenital mature teratomas of the umbilical cord are extremely rare. We report on a girl who presented with a ruptured omphalocele and a 7 cm mass connected to the umbilicus, which we resected on the first day of life. Histology revealed mature umbilical cord teratoma . On the 29th day of life, a secondary laparotomy was necessary to address the associated intestinal malformations (megaduodenum, stenotic small bowel with duplication and malrotation). After a prolonged hospital stay, we discharged the patient in age-appropriate conditions. Antenatal diagnosis of an umbilical cord tumor can be challenging in the presence of an omphalocele. Given the high prevalence of associated malformations, the finding of umbilical cord teratoma should be followed by a detailed and comprehensive neonatal workup for additional abnormalities.
Surgical Treatment of Congenital Radial Head Luxation in a Cat by Ostectomy of Radial Head
Authors: Verdese Pauline , Manfredini Sara , Formaggini Luca
Published: February 2022

Congenital radial head luxation was diagnosed in a 7-month-old, neutered female cat that presented a right forelimb lameness. Clinical and radiographic examination revealed a caudolateral luxation of the right radial head, which was treated by radial head ostectomy. For months, postoperative radiographic recheck documented remodelling of the radial head, without humero-radial conflict, and clinical examination revealed resolution of lameness and restoring of the normal elbow range of motion. To the authors' knowledge, this is the first case report of a congenital radial head luxation in a caudolateral direction in a cat that was successfully managed surgically with radial head ostectomy.
An Apple iPad a Day Brings the Doctor to You: Virtual Family-Centered Rounds in a Pediatric Intensive Care Unit
Authors: Solt Shannon A. , Stolfi Danielle , Ritter Victor Silva , Kihlstrom Margaret
Published: February 2022

The purpose of this study was to evaluate if virtual family-centered rounds (VFCR) in a pediatric intensive care unit (PICU) would improve communication without significantly increasing rounding time. An observational study was conducted recording rounding times of patient encounters. Then, in March 2019, English-speaking families were offered the opportunity to round virtually. Families were required to have access to a device with video conferencing capabilities and were video conferenced into rounds via Skype. Participants completed an online satisfaction survey. Rounding times were not significantly different for families present on rounds compared with not present (10 minutes 49 seconds vs. 9 minutes 42 seconds; p = 0.2). The average length of VFCR was 11 minutes 19 seconds; this was not statistically significant when compared with no family present (p = 0.5) or family present (p = 0.8). Majority of nurses (85%) and over half of physicians (53%) felt that VFCR were very helpful. One hundred percent of families and the majority of physicians and nurses felt that it positively impacted family communication. All families felt that VFCR improved their understanding of their child's medical condition, and the majority felt it improved their understanding of the treatment plan. VFCR positively impacts the communication in the PICU and can be used for families unable to be present for rounds without significantly increasing rounding times.
Tussock and tiller population dynamics on rotationally stocked Piatã palisadegrass (
Authors: Crestani Steben , Congio Guilhermo Francklin de Souza , Mascheroni Jorge Daniel Caballero , Geremia Eliana Vera , Carnevalli Roberta Aparecida , Mourão Gerson Barreto , da Silva Sila Carneiro
Published: February 2022

Context Integrated crop–livestock–forestry systems can be an alternative to monoculture pastures; however, the effect of the arboreal component on tillering and tussock dynamics of understorey grass canopy is not well understood. Aims Our objective was to evaluate the patterns of tillering dynamics, population stability and tussock distribution of Piatã palisadegrass (Urochloa brizantha) as affected by contrasting shading regimes in the Brazilian Amazon biome. Methods The following three shading regimes were assessed: pasture with no trees (no shading, NS), moderate shading (MS, 338 trees ha−1), and intense shading (IS, 714 trees ha−1). Pastures were rotationally grazed by dairy heifers. Paddocks from MS and IS were stratified into three sampling strips, including two closer to the tree rows (i.e. lateral) and one between the two lateral strips (i.e. central). Two methods for monitoring sward canopy light interception (LI) were used for IS regime, namely, LI taken under the tree canopy (i.e. inside) and LI was taken above the tree canopy (i.e. outside). Key results Relative to NS, there was a reduction in photosynthetically active radiation transmittance of 18.1% and 37.1% on MS and 49.9% and 52.0% on IS for central and lateral shading strips respectively. Overall, the increase in shading level was associated with a decrease in average tussock perimeter, tiller population density, and an increase in the frequency of bare ground. Conclusions Our findings clearly indicate the key role of the light environment as a determinant of Piatã palisadegrass horizontal structure. Implications It highlights the importance of planning the levels of tree density and layout in areas of crop–livestock–forestry integration.
Preliminary investigation of reproductive hormone profiles in the blacktip shark (
Authors: Verkamp Hannah J. , Hammerschlag Neil , Quinlan James , Langan Joseph A. , Sulikowski James A.
Published: February 2022

Accurate reproductive information is crucial for the effective management of sharks. Here, we used non-lethal methods to evaluate reproductive hormone profiles of blacktip sharks (Carcharhinus limbatus) off the coast of southern Florida (FL) as part of a preliminary investigation of this species’ reproductive patterns in the region. Circulating testosterone concentrations in males ranged from 0.04 to 320.7 ng mL−1, and concentrations peaked during months previously shown to represent peak spermatogenic activity. In females, circulating concentrations of oestradiol (E2) ranged from 12.5 to 941.4 pg mL−1, and progesterone (P4) ranged from 30.1 to 821.2 pg mL−1. E2 peaked during months with peak vitellogenic and ovulatory activity in previous studies; P4 displayed less variability among months. In general, changes in monthly hormone concentrations align well with the timing of reproductive events in C. limbatus in other regions. However, because of low monthly sample sizes and a lack of reproductive status confirmation, the female profiles raise interesting questions about this population’s reproductive cycle that could be explored in future studies. Additional studies should collect larger monthly samples and incorporate supplementary data to provide more insight into the reproductive cycle of this species in southern FL.
Heat shock proteins exhibit distinct spatiotemporal expression patterns in the domestic cat (
Authors: Liman Narin , Kuzkale Murat
Published: February 2022

Heat shock proteins (HSP) are significant regulators of cell proliferation, differentiation and apoptosis. HSP participate in ovarian physiology through proliferative and apoptotic mechanisms and the modulation of sex steroid receptor functions. We investigated whether the expression and localisation patterns of HSP in the domestic cat ovary vary with the oestrous cycle stage. Immunohistochemical analysis revealed cell type-specific localisation patterns of HSPD1/HSP60, HSPA/HSP70, HSPC/HSP90 and HSPH/HSP105 in several ovarian cells of the domestic cat, including oocytes, follicular (granulosa and theca cells) and luteal cells, stromal and thecal interstitial cells, stromal cells, and vascular endothelial and smooth muscle cells during the anoestrous, follicular and luteal phases of the oestrous cycle. Western blot results showed that the expression of three HSP (HSPD1/HSP60, HSPA/HSP70 and HSPH/HSP105) varied with the oestrous cycle stage. While the maximal expression of HSPD1/HSP60 and HSPH/HSP105 occurred during the luteal phase, the expression of HSPA/HSP70 was minimal. The expressions of HSPA/HSP70 and HSPH/HSP105 were low during the follicular phase compared to the anoestrous phase. In conclusion, the alterations that occur in the expression of HSP in the domestic cat ovary during the different stages of the oestrous cycle imply that these proteins participate in the regulation of ovarian function under different physiological conditions.
HYL1-CLEAVAGE SUBTILASE 1 (HCS1) suppresses miRNA biogenesis in response to light-to-dark transition
Authors: Jung Hyun Ju , Choi Suk Won , Boo Kyung-Hwan , Kim Jee-Eun , Oh Young Kyoung , Han Min Kyun , Ryu Moon Young , Lee Chang Woo , Møller Christian , Shah Pratik , Kim Gu Min , Yang Woorim , Cho Seok Keun , Yang Seong Wook
Published: February 2022

Significance

HYPONASTIC LEAVES 1 (HYL1)-CLEAVAGE SUBTILASE 1 (HCS1) is a novel negative regulator of microRNA (miRNA) biogenesis that degrades HYL1 in the cytoplasm. Furthermore, cytoplasm CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1) E3 ligase inhibit HCS1-mediated HYL1 degradation. The COP1-HYL1-HCS1 network may integrate two essential cellular pathways: the miRNA-biogenetic pathway and light signaling pathway. Our finding suggests a regulatory pathway in the miRNA-biogenetic system.
Effect of Chemical Treatment and Thermal Annealing in N2 Atmosphere on Copper Foil Surface for Graphene Growth by Direct-Liquid-Injection Chemical Vapor Deposition Process
Authors: Intaro Taworn , Taychatanapat Thiti , Suwanyangyaun Pattana , Botta Raju , Nuntawong Noppadon , Hodak Jose , Sanorpim Sakuntam
Published: February 2022

Copper foils are widely used as a substrate for graphene grown by chemical vapor deposition method. The qualities of Cu foils can significantly affect the characters of resulting graphene films. Here, we systematically investigated the effects of chemical treatments and thermal annealing at high temperatures (890-950 °C) in N2 atmosphere. We then compared the graphene quality grown by direct liquid injection chemical vapor deposition (DLI-CVD) method with cyclohexane (C6H12) precursor on un-treated and treated Cu foil. We found that the chemical treatment conditions can improve surface morphology of the Cu foil. In addition, the annealing process at 920 °C for 10 min in N2 atmosphere can increase the grain size and lead to a favorable crystal orientation of (111) plane. Raman and microscopy analyses of the graphene film, show higher yields of monolayer graphene, while, at other annealing conditions and un-treated Cu foil, multilayer graphene is observed.
Synthesis of novel activated carbon/BiVO4 nanocomposite photocatalysts for degradation of organic compounds in wastewater
Authors: Chaiwichian Saranyoo
Published: February 2022

Novel activated carbon/BiVO4 nanocomposite photocatalysts were straightforwardly prepared via an impregnation method. All the samples were characterized by using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectra (UV-vis DRS) and photoluminescence (PL) techniques. The photocatalytic efficiency of activated carbon/BiVO4 nanocomposite photocatalysts was estimated by rhodamine B dye degradation under visible light illumination. Results revealed that composited activated carbon on the surface of BiVO4 importantly improved the photocatalytic efficiency. In addition, the composited activated carbon was assisted to fast reduce in the recombination of photogenerated charges, resulting in enhanced photocatalytic efficiency. The amount of composited activated carbon had affected the photocatalytic efficiency. The 5.0 mol% activated carbon showed the highest photocatalytic efficiency for the degradation of rhodamine B dye under visible light irradiation. Moreover, the photocatalytic efficiency of 5.0 mol% activated carbon/BiVO4 nanocomposite photocatalyst showed a slight loss after five runs for rhodamine B dye degradation. The radical trapping experiments and mechanism of the improved photocatalytic efficiency in the degradation of rhodamine B dye were also proposed.
Effects of Natural Rubber Compound and Crumb Rubber on Mechanical and Morphological Properties of Biodegradable Poly(butylene succinate)
Authors: Singsang W , Petprom W , Junphong N , Charerntanom W , Srakaew N , Hasook A , Prasoetsopha N
Published: February 2022

Natural rubber compound was melt-mixed with biodegradable poly(butylene succinate) (PBS) using an internal mixer. The effect of natural rubber compound (NRC) content on the mechanical properties of PBS was examined. The amount of NRC of 0, 5, 10 and 15 percentage by weight were used. Moreover, crumb rubber (CR) of 5 phr was added into the blend of PBS/NRC (85/15). After mixing, the samples were ground with a grinder and formed to specimen test by hot compression molding. The results of the mechanical tests showed that NRC enhanced the toughness of PBS matrix. As a result, the elongation and impact resistance values increased. However, maximum tensile strength and the modulus of elasticity decreased with an increase in the NRC content. The addition of CR in the PBS/NRC blend resulted in a reduction of all mechanical properties. The morphology of the fractured surface was investigated by scanning electron microscope. It could be seen that the NRC had a good dispersion in the PBS matrix while the CR did not show good interfacial adhesion with the PBS matrix.
Synthesis and Characterization of Monetite from Calcium Carbonate Recovered from Carpet Waste
Authors: Janbooranapinij Kasidit , Yimponpipatpol Arinchai , Ngamthanacom Narueporn , Suthiprapar Jularpar , Panomsuwan Gasidit
Published: February 2022

Calcium carbonate (CaCO3) was recovered from the carpet waste by combustion at 500 °C under an air atmosphere. The CaCO3 had a pure calcite phase without detection of other crystalline phases, as confirmed by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) measurements. Dicalcium phosphate (CaHPO4) or monetite, which is known as a family of calcium phosphate-based biomaterials, was synthesized by mixing the CaCO3 recovered from the carpet waste with phosphoric acid (H3PO4) solution. The reaction was kept at a constant temperature of 80 °C for 24 h. The XRD and FTIR results demonstrated that the pure monetite phase was successfully formed by the reaction between CaCO3 and H3PO4. The energy-dispersive X-ray spectroscopy analysis confirmed that the monetite was composed of calcium, oxygen, and phosphorus. The results obtained in this work revealed that CaCO3 recovered from carpet waste could potentially be an alternative material for the synthesis of monetite under mild conditions.
Effect of sodium hydroxide on properties of shrimp-shells-extracted chitin nanofibers
Authors: Thongdonson K , Boonmahitthisud A , Tanpichai S
Published: February 2022

Shrimp shells from seafood wastes were used as a raw material to prepare chitin nanofibers (ChNFs) by combined chemical and mechanical treatments. The extraction of chitin from shrimp shells involved multistep procedures of deproteinization, demineralization and deacetylation. The deacetylation refers to the replacement process of acetyl groups by reactive amino groups (-NH2). After that, treated chitin were fibrillated by high-speed blending to disintegrate ChNFs. In this work, we studied the effect of sodium hydroxide (NaOH) concentrations (0 - 30 %wt) on properties of ChNFs. Fourier transform infrared (FT-IR) spectra showed with increasing concentrations of NaOH, the intensity of the peak located at ∼1550 cm-1, corresponding to the presence of amide groups (-NH) on chitin molecules decreased. This was an indication of the removal of acetyl groups. The thermal stability of ChNFs was subsequently analyzed by thermogravimetric analysis (TGA). With increasing the concentrations of NaOH, the lower thermal stability of ChNFs was obtained. In addition, the morphologies of ChNFs with widths of a few nanometers were observed by a field emission scanning electron microscope (FE-SEM). The prepared ChNFs in this work could be possibly used as a reinforcing agent for composite applications.
Effect of epoxidation levels on curing characteristic and mechanical properties of ENR/MFC composites
Authors: Bhakri S , Takenaka K , Boonmahitthisud A , Boondamnoen O
Published: February 2022

This study aimed to investigate the effect of epoxidation levels on the curing and tensile properties of epoxidized natural rubber (ENR)/microfibrillated cellulose (MFC) composites. ENRs with different levels of epoxidation were first prepared from natural rubber (NR) latex via ‘in situ’ performic epoxidation using 0.75 M formic acid and 1 M hydrogen peroxide at 50°C at various reaction times. The results from H1 NMR revealed that the reaction at 2, 4, and 6 hours could achieve 20, 30, and 40 mol % epoxidation, respectively. The introduction of epoxide groups into NR chains reduced the scorch and cure time along with the increase of the epoxy content. Furthermore, it was observed that the tensile strength rose remarkably at 30 mol% epoxidation (ENR30). Therefore, the ENR30 was subsequently chosen to prepare the composites with various amounts of MFC (1, 3, and 5 parts per hundred rubber, phr). Interestingly, incorporating MFC elevated tensile strength and elongation at break of ENR30. At 5 phr of MFC, the composite possessed the highest tensile strength and elongation at break value, which reached up to 31.07 MPa and 922.92%, respectively.
Influence of torrefaction on yields and characteristics of densified solid biofuel
Authors: Prasongthum N. , Duangwongsa N. , Khowattana P. , Suemanotham A. , Wongharn P. , Thanmongkhon Y. , Reubroycharoen P. , Attanatho L.
Published: February 2022

Torrefaction is a mild thermal pretreatment for enhancing the combustion property of biomass to be properly applied to biomass or co-firing power plants. The present research investigated mass yields, fuel characteristics and hydrophobicity of rubber wood pellet torrefied at different temperatures and residence times. Proximate and ultimate analyses, the enhancement factor of higher heating value, energy yield, lignocellulosic components and Fourier transform infrared spectroscopy (FT-IR) of torrefied samples were performed to evaluate the influence of the process parameters and compared to those of the untreated ones. The non-condensable and condensable products were analyzed by GC and GC-MS. The results showed that the torrefaction severity index (TSI) correlated sufficiently with the properties of torrefied biomass and was more sensitive to torrefaction temperature than residence time. The increase in the TSI value resulted in an increase in heating value but a decrease in energy yield. The energy density increased by 14% at 260 °C and reached up to 35% at torrefaction temperature of 300 °C. FT-IR analysis revealed that the contents of hydroxyl and carbonyl groups appeared in torrefied wood pellets were decreased and increased, respectively, due to the torrefaction process. Furthermore, the hydrophobicity of torrefied pellets can be significantly improved as torrefaction temperature increases. The non-condensable gaseous products were mostly composed of CO2, CO, and traces of CH4. While the organic compounds found in condensable liquid products were acids, ketones, furans and phenols.
Effects of Reaction Time on Degree of Substitution, Yield and Morphology of Carboxymethyl Cellulose from Banana Peel
Authors: Suchaiya V , Choochouy N , Chokboribal J , Khammee T , Nueangnun K , Jaroennon P
Published: February 2022

Carboxymethyl cellulose(CMC) was extracted from cultivated banana peel (BP) agricultural waste. Cellulose was first extracted from BP through delignification, bleaching and hydrolysis processes. Then, CMC was prepared by the carboxymethylation reaction using monochloroacetic acid as a modifying agent. A mixture of 30% sodium hydroxide solution and isopropanol was used as the solvent medium for etherification with reaction time of 1-5 hours. The effects of reaction time on physical appearance, chemical structure, degree of substitution (DS), percent yield (%yield) and morphology of CMC were studied. Results indicated that banana peel cellulose (BPC) powder could be extracted from BP with yield of 14.81%±7.20. CMC was successfully prepared from BPC powder and confirmed by FT-IR technique. DS and %yield of CMC increased when reaction time increased from 1 to 4 hours but decreased when reaction time reached 5 hours. Reaction time of 4 hours gave optimal DS and %yield at 0.61±0.05 and 152.65±17.93, respectively. BPC presented bulk particle shape with a dense and smooth surface. After etherification, morphology of BPC was changed to a mixture of small particles with fibrous shape and a porous rough surface.
Mechanical Properties and Biodegradability of Starch-based Biocomposite Films Reinforced with Microcrystalline Cellulose from Rice Embryo
Authors: Suklaw N , Ratanakamnuan U
Published: February 2022

In this research, glycerol-plasticized cassava starch/San Pa Tong sticky rice embryo plant microcrystalline cellulose (SPT-MCC) biocomposite films were prepared by solvent casting technique. SPT-MCC were extracted from sticky rice embryo plant by alkaline delignification process, bleached with hydrogen peroxide and hydrolysis with sulfuric acid, respectively. Effect of SPT-MCC content (0-60% wt% based on starch content) on thermal properties, mechanical properties and biodegradability of the biocomposite films were studied. Biodegradation of biocomposite films were investigated by soil burial test methods for 8 days. The biodegradability test results were compared with the degradation of three types commercial plastic bags. The result showed that thermal stability of biocomposite films decreased with the increasing of SPT-MCC addition while the tensile strength and Young’s Modulus of biocomposite films increased with the increment of SPT-MCC content. Starch-based biocomposite films reinforced with 10-40% wt% of SPT-MCC completely decomposed within 3 day, while the 50-60% wt% of SPT-MCC biocomposite films entirely degrade within 8 day.
Development of Starch-Polyvinyl Alcohol Films-based pH indicator for Detection of Penicillin G Residue in Raw Milk
Authors: Saengdee Pawasuth , Nuanthong Thanin , Chamnan Pomthip , Pattamang Pattaraluck , Thongsook Oraphan , Meananeatra Rattanawan , Ranron Norabadee , Pankong Krynnaras , Uahchinkul Warinrampai , Jeamsaksiri Wutthinan , Vongkamjan Kittiya , Chokboribal Jaroenporn , Atthi Nithi
Published: February 2022

The detection of residual penicillin G (Pen G) in raw milk is very crucial to prevent the adverse effect from the allergy of Pen G to dairy consumer. However, the conventional detection methods require highly expensive instruments, high-skill technicians and complicated sample preparation process. In this research, a Lab-on-a-Disc (LOAD) to detect the residual Pen G in raw milk was introduced. The LOAD (ϕ: 9.0 cm) consisted of 10 micro-channels with the maximum volume of 200 μL was fabricated by laser machining of PMMA sheets. The 8.0 μm-thick polyvinyl alcohol, PVA (0.03125 % w/v) mixed with corn starch at a ratio of 3:7 (v/v) and bromocresol purple (BCP) pH indicator (0.025 % w/v) film that used as a Pen G indicator was prepared by hydrogel method and coated on the micro-channels by drop casting method. After the LOAD was rotated at 5000 rpm for 5 min at 25 °C, the BCP-(S-PVA) indicator film with the solubility of 93.56 % was dissolved in a raw milk mixed with Pen G (4.0 ng/mL) and the color of BCP-(S-PVA) film has changed from dark violet to light violet. The detection limit of BCP-(S-PVA) film to detect the Pen G in raw milk that obtained from the linear dose response curve (R2: 0.9630) is 0.17 ng/mL. Therefore, the LOAD with the BCP-(S-PVA) pH indicator is the fast and accurate promising method to determine the residual Pen G in raw milk at room temperature.
Carbon Nanotube (CNTs) Production From Waste Cooking Oil As Anode Material For Li-Ion Batteries
Authors: Prompun Poramate , Ratchahat Sakhon , Kaveevivitchai Watchareeya , Kooamornpattana Wanida
Published: February 2022

Carbon nanotube (CNTs) have received growing interest as anode material on Li-ion batteries due to high electrical conductivity, large surface area and strong structure. In this study, CNTs were synthesized from waste cooking oil (WCO) by chemical decomposition process with various reaction temperatures (800, 900 and 1000 °C) and using ferrocene as catalysts. The characteristics of CNTs were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM) and gas adsorption analysis. Results show that the trend of pore size decreased, whereas the specific surface area of CNT increased with increasing reaction temperature. The electrochemical performance of CNTs samples as anode material for lithiumion batteries were investigated at C/4 rate. The results found that the highest specific discharge capacity was CNTs at reaction temperature 900 °C (474.34 mAh/g for first cycle and 213.75 mAh/g for 30 cycles) due to pore size and the specific surface area were suitable for Li-ion storage properties.
County-level analysis of current local capacity of agriculture to meet household demand: a dietary requirements perspective
Authors: Nixon Peter , Ramaswami Anu
Published: February 2022

With the goal of informing local food-action planning, this paper develops the first county-level database detailing agrifood consumption and production across 3114 counties in the United States. The database covers 12 070 food items that comprise the entire diet, mapping them to the production demand of 95 agrifood commodities. Agrifood demand is delineated further into fresh and processed components, along with characterization of animal feed, and compared with local food production to yield the current local agrifood capacity (CLC). CLC results are shown for individual agrifoods and for aggregated categories (e.g., on average, 0.03 for fruits and nuts, 0.24 for vegetables, 0.31 for non-meat animal products) across all US counties. CLC results for the entire diet find that a large proportion of US counties can be self-sufficient in individual agrifood commodities (ranging from <0.5% of counties for agrifoods like hops, papayas, and artichokes to 59% of counties for beef), and 23% of US counties can supply over half of their total human dietary demand through local production, but only 9% of the US population resides in these counties. Such granular, subnational baselines are essential to inform future goal-setting for urban agriculture.
Experimental investigation of ventilation bubble dynamics around a vertically moving cylinder under reduced ambient pressure
Authors: Chen Xiangbin , Xiao Wei , Gong Ruiyan , Yao Xiongliang , Hu Shaofeng
Published: February 2022

Ventilation bubble is widely used to reduce friction drag of object travelling in fluid. A large number of experimental studies are performed on the ventilation bubble in water tunnel, while little is known about it around vertically moving cylinder under reduced pressure. We aim to investigate dynamics of the ventilation bubble in vertically moving case. To support the study, a specialized experiment set-up is designed, based on which images of ventilation bubble around vertically moving cylinder under reduced ambient pressure can be captured and experiments are conducted to study the influence of velocities and flow rate on the ventilation bubble dynamics. In detail, we first describe the development of ventilation bubble and details of re-entrant jet. In addition to that, two types of re-entrant jets are observed, and the maximum velocity of re-entrant jet is obtained. Besides, four modes of development of ventilation bubbles’ closure patterns are concluded. Finally, geometric features of ventilation bubble are obtained through image processing which are then described and analyzed in detail. The above results contribute to the research on the control of vertically moving cylinder through ventilation bubble.
Linear instability of a perturbed Lamb–Oseen vortex
Authors: Maslowe Sherwin A
Published: February 2022

This paper presents an investigation of the stability of a vortex with azimuthal velocity profile

V
ˉ

=

1
−

1
−
ε

r
2

e

−

r
2

/

r

. When ε = 0, the Lamb–Oseen vortex model is recovered. Although the Lamb–Oseen vortex supports propagating waves known as Kelvin waves, the flow is stable according to Rayleigh’s circulation criterion. In this paper, on the other hand, the modified vortex profile admits linearly unstable disturbances for ε > 0 and we investigate their characteristics. These may be either axisymmetric or non-axisymmetric, but we find that the axisymmetric perturbations have the largest growth rates. When their growth rates are small, it becomes very difficult to solve the linear equation governing the axisymmetric perturbations because the eigenfunctions have a rapid exponential growth as one moves outward radially from the vortex center. To deal with such cases, a modified Riccati transformation was employed and found to be effective in solving the associated eigenvalue problem.
Aerosol formation pathways from aviation emissions
Authors: Prashanth Prakash , Eastham Sebastian D , Speth Raymond L , Barrett Steven R H
Published: February 2022

Aviation emissions are responsible for an estimated 24,000 premature mortalities annually and 3.5% of anthropogenic radiative forcing (RF). Emissions of nitrogen and sulfur oxides (NOx and SOx) contribute to these impacts. However, the relative contributions and mechanisms linking these emissions to formation and impacts of secondary aerosols (as opposed to direct aerosol emissions) have not been quantified, including how short-lived aerosol precursors at altitude can increase surface-level aerosol concentrations. We apply global chemistry transport modeling to identify and quantify the different chemical pathways to aerosol formation from aviation emissions, including the resulting impact on radiative forcing. We estimate a net aerosol radiative forcing of –8.3 mWm−2, of which –0.67 and –7.8 mWm−2 result from nitrate and sulfate aerosols respectively. We find that aviation NOx causes –1.7 mWm−2 through nitrate aerosol forcing but also –1.6 mWm−2 of sulfate aerosol forcing by promoting oxidation of SO2 to sulfate aerosol. This accounts for 21% of the total sulfate forcing, and oxidation of SO2 due to aviation NOx is responsible for 47% of the net aviation NOx attributable RF. Aviation NOx emissions in turn account for 41% of net aviation-aerosol-attributable RF (non-contrail). This is due to ozone-mediated oxidation of background sulfur and the ‘nitrate bounce-back’ effect, which reduces the net impact of sulfur emissions. The ozone-mediated mechanism also explains the ability of cruise aviation emissions to significantly affect surface aerosol concentrations. We find that aviation NOx emissions cause 72% of aviation-attributable, near-surface aerosol loading by mass, compared to 27% from aviation SOx emissions and less than 0.1% from direct emission of black carbon. We conclude that aviation NOx and SOx emissions are the dominant cause of aviation-attributable secondary inorganic aerosol radiative forcing, and that conversion of background aerosol precursors at all altitudes is amplified by enhanced production of aviation attributable oxidants at cruise altitudes.
Kinetics of sulphur dissolution in lithium–sulphur batteries
Authors: Dent Matthew , Jakubczyk Ewa , Zhang Teng , Lekakou Constantina
Published: February 2022

This study investigates and determines the dissolution kinetics of solid sulphur in DOL:DME solution, a typical electrolyte solution for lithium–sulphur (Li–S) batteries, at four different temperatures, in the range of 17 °C–20 °C. The dissolution kinetics is considered as a function of the solid sulphur-solution interfacial area. The analysis yielded fast dissolution kinetics with a mass transfer coefficient of 2.3 × 10−3 m s−1 at 20 °C but low sulphur solubility of 0.058 S mol lt−1, with the latter being a limiting factor in sulphur dissolution. In later stages, swelling of the solid sulphur region was also observed as a function of time from which the diffusion coefficient of the DOL:DME solution in the solid sulphur was determined. A novel model for the sulphur dissolution and electrolyte impregnation in a Li–S cathode in battery fabrication is presented taking into account the pore size distribution of the cathode host. A computer simulation was carried out and the model and the dissolution parameter values were validated by comparing the predictions with experimental data from in operando microscopy during the dissolution of sulphur and infiltration of the DOL:DME solution in a commercial sulphur-conductive carbon cathode.
Thermodynamics of spin crossover in ferropericlase: an improved LDA + Usc calculation
Authors: Sun Yang , Zhuang Jingyi , Wentzcovitch Renata M
Published: February 2022

We present LDA + Usc calculations of high-spin (HS) and low-spin (LS) states in ferropericlase (fp) with an iron concentration of 18.75%. The Hubbard parameter U is determined self-consistently with structures optimized at arbitrary pressures. We confirm a strong dependence of U on the pressure and spin state. Static calculations confirm that the antiferromagnetic configuration is more stable than the ferromagnetic one in the HS state, consistent with low-temperature measurements. Phonon calculations guarantee the dynamical stability of HS and LS states throughout the pressure range of the Earth mantle. Compression curves for HS and LS states agree well with experiments. Using a non-ideal mixing model for the HS to LS states solid solution, we obtain a crossover starting at ∼45 GPa at room temperature and considerably broader than previous results. The spin-crossover phase diagram is calculated, including vibrational, magnetic, electronic, and non-ideal HS–LS entropic contributions. Our results suggest the mixed-spin state predominates in fp in most of the lower mantle.
Magnetic solitons in an antiferromagnetic waveguide
Authors: Wu Zhong
Published: February 2022

The properties of transverse magnetic (TM) waves propagating along a single interface between two semi-infinite nonlinear antiferromagnetic materials are investigated. The surface waves exist in the form of bright magnetic solitons. The frequency characteristics for the passband and stopband are analytically studied. We discuss the possibility of controlling the bandwidth of the passband which is determined by the parameters of the materials composing the guiding structure. We expect that the theoretical findings could provide ideas for exploring potential applications in terahertz region.
Fiber product of Riemann surfaces
Authors: Hidalgo Rubén , Reyes-Carocca Sebastián , Vega Angélica
Published: February 2022

If

S

0

,

S

1

,

S

2

S_{0}, S_{1}, S_{2}

are connected Riemann surfaces,

β

1

:

S

1

→

S

0

\beta _{1}:S_{1} \to S_{0}

and

β

2

:

S

2

→

S

0

\beta _{2}:S_{2} \to S_{0}

are surjective holomorphic maps, then the associated fiber product

S

1

×

(

β

1

,

β

2

)

S

2

S_{1} \times _{(\beta _{1},\beta _{2})} S_{2}

has the structure of a one-dimensional complex analytic space, endowed with a canonical map

β
:

S

1

×

(

β

1

,

β

2

)

S

2

→

S

0

\beta : S_{1} \times _{(\beta _{1},\beta _{2})} S_{2} \to S_{0}

, such that, for

j
=
1
,
2

j=1,2

,

β

j

∘

π

j

=
β

\beta _{j} \circ \pi _{j}=\beta

, where

π

j

:

S

1

×

(

β

1

,

β

2

)

S

2

→

S

j

\pi _{j}: S_{1} \times _{(\beta _{1},\beta _{2})} S_{2} \to S_{j}

is the natural coordinate projection. The connected components of the complement of its singular locus provide its irreducible components. A Fuchsian description of the irreducible components of

S

1

×

(

β

1

,

β

2

)

S

2

S_{1} \times _{(\beta _{1},\beta _{2})} S_{2}

is provided and, as a consequence, we obtain that if one of the maps

β

j

\beta _{j}

is a regular branched covering, then all its irreducible components are isomorphic. Also, if both

β

1

\beta _{1}

and

β

2

\beta _{2}

are of finite degree, then we observe that the number of these irreducible components is bounded above by the greatest common divisor of the two degrees, and that such an upper bound is sharp. We also provide sufficient conditions for the irreducibility of the connected components of the fiber product.

In the case that

S

0

=

C

^

S_{0}=\widehat {\mathbb C}

, and

S

1

S_{1}

and

S

2

S_{2}

are compact, we define the strong field of moduli of the pair

(

S

1

×

(

β

1

,

β

2

)

S

2

,
β
)

(S_{1} \times _{(\beta _{1},\beta _{2})} S_{2},\beta )

and observe that this field coincides with the minimal field containing the fields of moduli of both pairs

(

S

1

,

β

1

)

(S_{1},\beta _{1})

and

(

S

2

,

β

2

)

(S_{2},\beta _{2})

. Finally, in the case that all surfaces

S

1

S_{1}

,

S

2

S_{2}

and

S

0

S_{0}

are compact and the fiber product is a connected Riemann surface, we observe that the Jacobian variety

J
(

S

1

×

(

β

1

,

β

2

)

S

2

)
×
J

S

0

J(S_{1} \times _{(\beta _{1},\beta _{2})}S_{2}) \times JS_{0}

is isogenous to

J

S

1

×
J

S

2

×
P

JS_{1} \times JS_{2} \times P

, where

P
P

is a suitable abelian subvariety of

J
(

S

1

×

(

β

1

,

β

2

)

S

2

)

J (S_{1} \times _{(\beta _{1},\beta _{2})}S_{2})

.
Dental occlusal surface and seed dispersal evolution inTapirus(Mammalia: Perissodactyla)
Authors: Dumbá Larissa Costa Coimbra Santos , Rodrigues Flávio Henrique Guimarães , Maclaren Jamie Alexander , Cozzuol Mario Alberto
Published: February 2022

Most tapirs are good seed dispersers. An exception is the Malayan tapir, Tapirus indicus, a seed predator (mainly of large seeds). Little is known about the capacity for tapirs to disperse seeds throughout their evolutionary history. We used the occlusal surface area (OSA) of tapir cheek teeth as a predictor of seed dispersal potential in living and extinct tapir species. We used T. indicus as a reference for an extant tapir that mostly eats seeds. The OSA was calculated by multiplying the maximal width and length of molars and premolars. A threshold based on T. indicus OSA was projected onto a box plot analysis and used as a predictor for tapir seed dispersal potential. Ordination and statistical results suggest that tooth morphology is uniform between Tapirus species and that size is the main factor affecting variation. Maxillary teeth show greater variation in morphology than mandibular teeth between species. The results suggest that extant South American tapirs are good seed dispersers. North American tapirs present variable OSAs, and Asian tapirs have a low capacity for dispersion. All European tapirs were probably efficient seed dispersers. We present the first morphometric evidence for seed dispersal capacity in tapirs, with ramifications for tapir palaeoecology.
Clostridium difficile infection after ileostomy closure and anastomotic failure in rectal cancer surgery patients
Authors: Kim Young Il , Yu Chang Sik , Kim Yang Soo , Kim Chan Wook , Lee Jong Lyul , Yoon Yong Sik , Park In Ja , Lim Seok-Byung , Kim Jin Cheon
Published: February 2022

Background

Diverting ileostomy during resection of rectal cancer is frequently performed in patients at risk of anastomotic failure. Clostridium difficile infection (CDI) is reported to be frequent in patients who receive ileostomy closure with a questionable association to postoperative anastomosis leak. The primary aim of this study was to determine the incidence of CDI following ileostomy closure in patients who underwent rectal cancer surgery; the secondary aim was to assess the rate of postileostomy closure CDI in patients who presented with leakage at the original colorectal anastomosis site.

Methods

Medical records of patients with rectal cancer who underwent ileostomy closure between January 2015 and December 2019 were retrospectively reviewed. All patients had previously received resection and anastomosis for primary rectal cancer with diverting ileostomy. Data regarding CDI incidence, preoperative status, perioperative management, and clinical outcomes were collected. CDI positivity was determined by direct real-time PCR and enzyme-linked fluorescent assays for detecting toxin A and B.Statistical analyses were computed for CDI risk factors.

Results

A total of 1270 patients were included and 208 patients were tested for CDI owing to colitis-related symptoms. The incidence of CDI was 3.6 per cent (46 patients). Multivariable analysis for CDI risk factors identified adjuvant chemotherapy (hazard ratio (HR) 2.28; P = 0.034) and colorectal anastomosis leakage prior to CDI (HR 3.75; P = 0.008). Finally, patients with CDI showed higher colorectal anastomosis leakage risk in multivariable analysis after ileostomy closure (HR 6.922; P = 0.001).

Conclusion

Patients with CDI presented with a significantly higher rate of colorectal anastomosis leakage prior to ileostomy closure.
A new genus of Lythraceae emerges from rocky outcrops of the Atlantic Forest in Brazil
Authors: Cavalcanti Taciana B , Facco Marlon G , Inglis Peter W , Graham Shirley A , Gonella Paulo M
Published: February 2022

Recent collections of Lythraceae from an isolated mountain range in eastern Brazil were found to possess a unique morphology including spurless, weakly actinomorphic floral tubes, two deep red petals, a stipitate ovary and irregularly circumscissile dehiscence of a thickened capsule, characters typically applied to taxon recognition at the generic level. Genomic DNA was extracted from herbarium specimens or silica-dried leaf tissue and subjected to Illumina sequencing, and a phylogenetic analysis was performed based on a combination of plastid trnL-trnF and rpl16 and nuclear ribosomal ITS sequences. Sequences of 22 genera of Lythraceae, including 74 Cuphea spp. representing all recognized sections of the genus and three Pleurophora spp., were included in the analysis; Ludwigia octovalvis (Onagraceae) was used to root the trees. A maximum-likelihood tree was reconstructed based on the concatenated matrix. Strong morphological evidence was found to recognize a new genus and species in Lythraceae: Gyrosphragma latipetala sp. nov., gen. nov. The same characteristics also occur in a little-known species, Cuphea santos-limae, which we transfer to Gyrosphragma. Molecular phylogenetic analysis confirms Gyrosphragma as a monophyletic genus, sister to Cuphea; together these genera form a clade with Pleurophora. The new genus, supported by morphological and molecular evidence, adds new features and extends knowledge on the ecological and geographical diversity within Lythraceae.
Machine Learning to Assist in Large-Scale, Activity-Based Synthetic Cannabinoid Receptor Agonist Screening of Serum Samples
Authors: Janssens Liesl K , Boeckaerts Dimitri , Hudson Simon , Morozova Daria , Cannaert Annelies , Wood David M , Wolfe Caitlin , De Baets Bernard , Stock Michiel , Dargan Paul I , Stove Christophe P
Published: February 2022

Background

Synthetic cannabinoid receptor agonists (SCRAs) are amongst the largest groups of new psychoactive substances (NPS). Their often high activity at the CB1 cannabinoid receptor frequently results in intoxication, imposing serious health risks. Hence, continuous monitoring of these compounds is important, but challenged by the rapid emergence of novel analogues that are missed by traditional targeted detection strategies. We addressed this need by performing an activity-based, universal screening on a large set (n = 968) of serum samples from patients presenting to the emergency department with acute recreational drug or NPS toxicity.

Methods

We assessed the performance of an activity-based method in detecting newly circulating SCRAs compared with liquid chromatography coupled to high-resolution mass spectrometry. Additionally, we developed and evaluated machine learning models to reduce the screening workload by automating interpretation of the activity-based screening output.

Results

Activity-based screening delivered outstanding performance, with a sensitivity of 94.6% and a specificity of 98.5%. Furthermore, the developed machine learning models allowed accurate distinction between positive and negative patient samples in an automatic manner, closely matching the manual scoring of samples. The performance of the model depended on the predefined threshold, e.g., at a threshold of 0.055, sensitivity and specificity were both 94.0%.

Conclusion

The activity-based bioassay is an ideal candidate for untargeted screening of novel SCRAs. The combination of this universal screening assay and a machine learning approach for automated sample scoring is a promising complement to conventional analytical methods in clinical practice.