bluuebunny/crossref_metadata_2025 huggingface dataset:
Effervescent tablet‐assisted demulsified dispersive liquid–liquid microextraction based on solidification of floating organic droplet for determination of methadone in water and biological samples prior to GC‐flame ionization and GC‐MS
Authors: Jafarinejad Masoomeh , Ezoddin Maryam , Lamei Navid , Abdi Khosrou , Babhadi‐Ashar Nima , Pirooznia Nazanin , Akhgari Maryam
Published: June 2020

A novel effervescent tablet‐assisted demulsified dispersive liquid–liquid microextraction based on the solidification of floating organic droplet was developed to determine methadone prior to gas chromatography with flame ionization detection and gas chromatography with mass spectrometry. In this method, a tablet composed of citric acid, sodium carbonate, and 1‐undecanol was utilized. The resulting effervescent tablet generated carbon dioxide in situ to disperse 1‐undecanol in the sample. Thus, the dispersive and extraction processes were performed in one synchronous step. An aliquot of acetonitrile as the demulsifier solvent was used for the separation of two phases instead of centrifugation. Under optimal conditions, the developed method was linear up to 50 000 µg/L with correlation coefficients higher than 0.99. Moreover, limits of detection and limits of the quantification were in the range of 3‐10  and 7‐30 µg/L in water and biological samples, respectively. Intra‐ and interday precisions (n = 6) of the spiked methadone at a concentration level of 50 µg/L were over ranges of 5.1‐6.8% and 5.7‐7.1%, respectively. The preconcentration factors and recovery values were obtained in the range of 140‐145 and 98.1 to 101.6% in real samples, respectively.
Emotion Dysregulation Prospectively Predicts Posttraumatic Stress Disorder Symptom Severity 3 Months After Trauma Exposure
Authors: Forbes Courtney N. , Tull Matthew T. , Rapport Daniel , Xie Hong , Kaminski Brian , Wang Xin
Published: June 2020

Despite growing evidence in support of emotion dysregulation as a risk factor for the development of posttraumatic stress disorder (PTSD) following trauma exposure, few studies have examined temporal relations between emotion dysregulation and the onset and/or worsening of PTSD symptoms over time. The aim of the present study was to extend research on temporal associations between emotion dysregulation and PTSD in a sample of individuals recruited from hospital emergency departments soon after a traumatic event. Adult participants (N = 85; 62.4% female) completed self‐report measures of emotion dysregulation and PTSD symptoms within 2 weeks of experiencing a traumatic event. Symptoms of PTSD were assessed approximately 3 months posttrauma. The results of a hierarchical linear regression analysis demonstrated that the inclusion of emotion dysregulation accounted for a significant amount of unique variance, β = .23, ΔR2 = .04, p = .042, in 3‐month PTSD symptom severity over and above other risk factors and baseline PTSD symptoms. No specific facet of emotion dysregulation emerged as a significant predictor of 3‐month PTSD symptoms when all facets were included on the same step of the model, βs = −.04–.33, ps = .133–.954. These results demonstrate that posttraumatic emotion dysregulation may predict PTSD symptoms 3 months after trauma exposure. These findings are consistent with a growing body of literature that speaks to the relevance of emotional processes to the onset and maintenance of PTSD following exposure to a traumatic event.
Sol–Gel Transitions of Comb‐Like Polymethacrylate Copolymers by Mechano‐Thermal Stimuli in Water
Authors: Jonnalagadda Umesh S. , Nguyen Tuan Minh , Li Feifei , Lee Jim H. C. , Liu Xu , Goto Atsushi , Kwan James J.
Published: June 2020

Sonogelation by supramolecular gelators is highlighted as a paradigm shift for their potential applications in material and biomedical sciences. Yet, these materials require organic solvents and low‐frequency ultrasound, limiting their utility. Here, a comb‐like polymethacrylate copolymer is synthesized with 2,6‐bis(1‐methylbenzimidazolyl)‐4‐oxypyridine tridentate ligand randomly distributed on poly(ethylene glycol) side chains. Upon addition of zinc perchlorate salt, this copolymer rapidly forms a hydrogel after exposure to either mechanical (i.e., ultrasound) or thermal stimuli. Spectroscopic analysis, to elucidate the mechanism, indicates metal ion coordination to ligand as well as the carbonyl and ethylene glycol units; interestingly, 1H‐NMR suggests that the coordination between tridentate ligand moiety and Zn2+ is unexpectedly weaker in water than in acetonitrile. Investigations by dynamic light scattering indicates that the copolymer forms nanodispersions in excess salt, which coalesces to form a hydrogel by either heating or high intensity focused ultrasound (HIFU). Rheological quantification of these gels suggests stronger crosslinking by HIFU compared to heating.
Wear behavior of laser metal deposited 17‐4 PH SS‐W composite at varied tungsten powder flow rate
Authors: Mahamood R.M. , Adeyemi A.A. , Akinlabi S.A. , Hassan S. , Fatoba O.S. , Akinlabi E.T.
Published: June 2020

This research studies the wear behavior of laser metal deposition of 17‐4 PH SS‐W composite using a 6 mm alumina‐stainless steel ball under a load of 10 N, for 16 minutes, 40 seconds and with acquisition rate of 100 Hz conducted at 25 °C. The effect of laser power of between 2600 W and 1500 W; and powder flow rate of between 0.5 min−1 and 2.0 min−1 on wear resistance is investigated. Other processing parameters are constant throughout the experiments. The results show that the 17‐4 PH SS‐W composite produced at a high laser power of 2600 W exhibits a higher wear resistance as compared to the 17‐4 PH SS‐W composite samples produced at low laser power of 1500 W. The 17‐4 PH SS‐W composite sample produced at high laser power of 2600 W with tungsten powder flow rate of 2.0 min−1 has the highest wear resistance with wear volume of 0.0276 mm3 and wear rate of 8.8 ⋅ 10−5 mm3/N m while the 17‐4 PH SS‐W composite sample produced at a low laser power of 1500 W with tungsten powder flow rate of 1.0 min−1 has the wear volume of 0.02834 mm3 and wear rate of 9.0 ⋅ 10−5 mm3/N m.
Effects of side‐groove and loading rate on the fracture properties of aluminium alloy AL‐6061
Authors: Kadhim M.H. , Latif N.A. , Harimon M.A. , Shamran A.A. , Abbas D.R.
Published: June 2020

The side‐groove effect on the fracture behavior of aluminum alloy AL‐6061 in single edge notch bending (SENB) specimens was studied. Aluminum alloys are broadly used to reduce the weight of vehicles as a structural component due to the excellent mechanical properties, lightweight characteristics, easy fabrication, and high specific strength, as aluminum alloys are exposed to high velocity and different loads during accidents. Therefore, acknowledging the impact behaviors of aluminum alloys are crucial. In the current research, 3‐point bending test was performed at various loading rates of 10 mm/min, 30 mm/min and 50 mm/min on different specimen thicknesses of 10 mm, 15 mm, 20 mm and 25 mm and several side‐groove depths. The side‐groove depth is determined according to the American Society for Testing and Materials (ASTM E399) requirements standard. The result indicates that the shear lips ratio of fracture surface was decreased, which consequently showed a change of large scale yielding to small scale yielding with increasing the specimen thicknesses. Accordingly, J values were increased with increasing the specimen thicknesses. Fracture surface observation shows that the fracture manners are ductile and less ductile as the side‐groove increased. Conclusively, the ductility of Al‐6061 alloy slightly decreased with increasing side‐groove depths and loading rates.
SlowN‐acetylation as a possible contributor to bladder carcinogenesis
Authors: El Kawak Michelle , Dhaini Hassan R. , Jabbour Michel E. , Moussa Mohamad A. , El Asmar Khalil , Aoun Mona
Published: June 2020

Bladder cancer (BCa) is an exophytic tumor that presents as either noninvasive confined to the mucosa (NMIBC) or invading the detrusor muscle (MIBC), and was recently further subgrouped into molecular subtypes. Arylamines, major BCa environmental and occupational risk factors, are mainly metabolized by the genetically polymorphicN‐acetyltransferases 1, NAT1 andNAT2. In this study, we investigated the association betweenN‐acetyltransferases genetic polymorphism and key MIBC and NMIBC tumor biomarkers and subtypes. A cohort of 250 males with histologically confirmed urothelial BCa was identified. Tumors were genotyped forNAT1andNAT2using real‐time polymerase chain reaction (PCR), and characterized for mutations inTP53, RB1, andFGFR3by PCR‐restriction fragment length polymorphism. Pathology data and patients' smoking status were obtained from medical records. Pearsonχ2and Fisher exact tests were used to check for associations and interactions. Results show thatNAT1G560A polymorphism is significantly associated with higher muscle‐invasiveness (MIBC vs NMIBC;P = .001), higher tumor grade (high grade vs low grade;P = .011), and higherFGFR3mutation frequency within the MIBC subgroup (P = .042; .027).NAT2G857A polymorphism is also found to be significantly associated with higher muscle‐invasiveness (MIBC vs NMIBC;P = .041). Our results indicate that slowN‐acetylation is a contributor to bladder carcinogenesis and muscle‐invasiveness. These findings highlightNAT1as a biomarker candidate in BCa and a potential target for drug development.
Endocrine profiling in patients with Fanconi anemia, homozygous for a FANCG founder mutation
Authors: Dillon Bronwyn , Feben Candice , Segal David , du Plessis Johannes , Reynders David , Wainwright Rosalind , Poole Janet , Krause Amanda
Published: June 2020

Background

Fanconi anemia (FA) is phenotypically diverse, hereditary condition associated with bone marrow failure, multiple physical abnormalities, and an increased susceptibility to the development of malignancies. Less recognized manifestations of FA include endocrine abnormalities. International discourse has highlighted that these abnormalities are widespread among children and adults with FA. To date there has been no systematic study that has evaluated the endocrine abnormalities in a cohort of patients with FA, homozygous for a founder mutation (c.637_643del (p.Tyr213Lysfs*6)) in FANCG. The objectives of the study were to evaluate endocrine gland function in patients with FA of a single FA genotype, and to determine the frequency and nature of endocrine abnormalities in this group.

Methods

Cross‐sectional, descriptive study of 24 South African patients of African ancestry with FA (homozygous for a FANCG founder mutation). Outcomes measured included growth, pubertal status, growth hormone axis screening, thyroid gland function, glucose and insulin metabolism and bone age (BA).

Results

Endocrine dysfunction was present in 70.8% (17 of 24), including abnormal insulin‐like growth factor 1 (IGF‐1)/insulin‐like growth factor‐binding protein 3 (IGFBP‐3) in 25.0% (6 of 24), insulin resistance in 41.7% (10 of 24), abnormal thyroid function in 16.7% (4 of 24) and short stature in 45.8% (11 of 24). No abnormalities of glucose metabolism were identified. Abnormal pubertal status was seen in three males (12.5%). Abnormal BAs were present in 34.8% (8 of 23).

Conclusion

Endocrine abnormalities occur at a high frequency in patients with FA, homozygous for a FANCG founder mutation, similar to other FA cohorts. Our data are specific to FA patients with a single genotype, and therefore provide the first genotype‐phenotype information on endocrine abnormalities in South African patients, homozygous for a FANCG founder mutation. Recommendations regarding endocrine screening in this patient subgroup are made, including, but not limited to, baseline testing of thyroid function, fasted insulin and glucose, and IGF‐1 and IGFBP‐3.
MHA screening results point to increasing wave of MH impacts
Authors: Canady Valerie A.
Published: June 2020

Concerns of loneliness and isolation, occurring nearly two months following the pandemic, have been cited by the greatest percentage of moderate to severe depression (73%) and anxiety (62%) screeners as contributing to mental health problems “right now,” according to new data released June 2 by Mental Health America (MHA).
Spin crossover properties of Fe(III) complexes in [Fe (bzacen)(tvp)]BPh4·nSolv chain structures: EPR study
Authors: Ivanova Tatyana A. , Ovchinnikov Igor V. , Turanova Olga A. , Bazan Leah V. , Shustov Vladimir A. , Batulin Ruslan G. , Cherosov Mikhail A.
Published: June 2020

Two types of Fe(III) polynuclear iron(III) 1D‐chain coordination compounds of the general formula [Fe (L)(tvp)]BPh4 nSolv, where L = dianion of N,N′‐ethylenebis (benzoylacetylacetone)2,2′‐imine (bzacen), tvp = 1,2‐di(4‐pyridyl)ethylene were synthesized and studied by the electron paramagnetic resonance (EPR) and magnetic susceptibility methods in the temperature range (100–300) К. Two types of spin‐variable complexes are formed depending on the time of precipitation of the complexes from the same solution leading to differently solvated species. They have different characteristics of the local ligand field and the spin transition behavior. The thermodynamic parameters of spin transitions were determined from the temperature dependence of the EPR signals integral intensity. The energy levels splitting values obtained by analyzing g‐factors of low‐spin Fe(III) centers evidenced not only on the crucial role of low‐symmetry distortions on the principal possibility of spin‐crossover processes, but also on the temperature peculiarities of spin transitions.
Cooperativity in a cycloalkane‐1,2/1,3‐polyol corona: Topological hydrogen bonding in 1,2‐diol motifs
Authors: Lomas John S. , Rosenberg Robert E. , Brémond Eric
Published: June 2020

A corona, consisting of 18 carbon atoms bearing 12 hydroxy groups in a continuous hydrogen‐bonded chain, is built up by alternating degenerate conformations of alternating alkane‐1,2‐diol and 1,3‐diol motifs. Geometries, proton nuclear magnetic resonance shifts and interaction energies for the dodecahydroxycyclo‐octadecane and selected fragments are determined by density functional calculations at the B3LYP/6‐311+G(d,p) level. Cooperative effects of O–H⋯O–H bonding are evident from the simple juxtaposition of these two motifs with a common OH group in butane‐1,2,4‐triol conformers. Bracketing a 1,2‐diol motif with two 1,3‐diol motifs in hexane‐1,3,4,6‐tetrol leads to a structure in which the 1,2‐diol motif displays a bond critical point for hydrogen bonding. This is associated with enhancement of the shift of the hydrogen‐bonded OH proton and of the corresponding H⋯O interaction energy. The full corona has a complete outer ring of O–H⋯O–H bond paths, and an inner ring of bond paths, due to C–H⋯H–C hydrogen–hydrogen bonding, which result in a central ring critical point. The topological O–H⋯O–H hydrogen bond, never seen in simple alkane‐1,2‐diols, is associated with cooperative enhancement of the H⋯O interaction energy, but this is not a necessary condition for a bond path: values for topological C–H⋯H–C hydrogen–hydrogen bonds can be as low as −0.4 kcal mol−1.
Development of a flowchart reflecting the current attitude and approach towards idiopathic overactive bladder treatment in Belgium: A Delphi study
Authors: Ghijselings Lynn , Hervé Francois , Van der Aa Frank , De Wachter Stefan , Pauwaert Kim , Haddad Rebecca , Beeckman Dimitri , Pattyn Piet , Everaert Karel
Published: June 2020

Aims

Idiopathic overactive bladder syndrome (iOAB) is a prevalent condition in urological practice. The variability in management between specialists and between centers remains high. Even existing guidelines contain inconsistencies. We aimed to develop a treatment algorithm for iOAB for use in daily clinical practice.

Methods

From October 2018 till November 2019, a Delphi study was conducted to obtain expert consensus on the management of iOAB. Members from the Belgian Working Group of Functional Urology were asked to rate online statements, based on gaps and variabilities between the American Urology Association (AUA), European Association of Urology (EAU) and International Consultation on Incontinence (ICI) guidelines on iOAB. The consensus was reached if ≥75% of the panel agreed on the level of appropriateness. Two Delphi rounds and an open discussion session were held.

Results

Twenty out of 49 members completed the first round and 18 completed the second round. The consensus was reached on 44/143 statements and 15/56 statements in the first and second round, respectively. The consensus was reached on criteria by which to phenotype OAB patients, the terminology relating to the first‐, second‐ and third‐line treatment, the duration of therapies, the chronological order, and the choice between therapies. No consensus was reached on the role of percutaneous tibial nerve stimulation (PTNS) in the treatment algorithm.

Conclusions

A flowchart reflecting the current attitude and approach of a Delphi expert panel towards the treatment of iOAB was developed. We propose its use in daily clinical practice to increase the standardization of OAB treatment.
Influence of compatibilizer and multifunctional additive loadings on flame retardation, plasticization, and impact modification of polylactide and poly(butylene adipate‐co‐terephthalate) biodegradable blends
Authors: Phetwarotai Worasak , Suparanon Tunsuda , Phusunti Neeranuch , Potiyaraj Pranut
Published: June 2020

The poor compatibility and flame retardation of polylactide (PLA) and poly(butylene adipate‐co‐terephthalate) (PBAT) blends seriously limit their applications. This study focused on the mechanical properties and flame retardancy of a PLA/PBAT blend under the influence of different levels of compatibilizer and multifunctional additives (MFA). PLA and PBAT were successfully compatibilized via reactive blending in a twin‐screw extruder. The flame retardation, flexibility, and impact toughness of the compatibilized blend were improved by the presence of tricresyl phosphate (TCP) and triethyl citrate (TEC). Separately and in combination, the two additives played crucial roles in flame retardant effectiveness, plasticization, and impact modification. The compatibilized blend displayed a UL‐94 V‐0 rating and exhibited a high limiting oxygen index (LOI). A slight reduction in thermal stability was exhibited when 20 phr TCP was incorporated into the blend. During combustion, an integrated char layer formed on the compatibilized blend surface and retarded flammability. The combination of TCP and TEC not only significantly improved dripping behavior and flame‐retardant properties of the compatibilized blend but also cooperatively enhanced the elongation at break and impact strength without impacting tensile strength, Young's modulus, LOI value, and thermal stability. The failure behavior of the blend changed from brittle to ductile, as evidenced by SEM, which revealed elongated fibrils after tension. These characteristics were associated with the presence of the MFAs and the improved interfacial adhesion between PLA and PBAT. As a result, flame retardation, flexibility, and impact resistance were enhanced. These improvements permit the wider application of PLA, especially in the electronic and automotive fields.

Highlights

Compatibilized PLA/PBAT blend achieved the V‐0 rating and had a high LOI.

Both TCP and TEC could be used as multifunctional additives (MFAs) in the compatibilized blend.

Combination of MFAs synergistically enhanced elongation at break and impact strength without impacting other properties of the blends.

These improvements permit the wider application of PLA, especially in the electronic and automotive fields.
Effect of the COVID‐19 pandemic on anxiety among children with cystic fibrosis and their mothers
Authors: Pınar Senkalfa Burcu , Sismanlar Eyuboglu Tugba , Aslan Ayse T. , Ramaslı Gursoy Tugba , Soysal Azime S. , Yapar Dilek , İlhan Mustafa N.
Published: June 2020

Background

We aimed to evaluate anxiety among children with cystic fibrosis (CF) and their mothers related to the COVID‐19 pandemic.

Methods

A total of 45 patients with CF and their mothers were enrolled in the study together with 90 age‐matched healthy children and their mothers as a control group. The State and Trait Anxiety Inventory (STAI) was administered by teleconference with children aged 13 to 18 years old and their mothers. The STAI for children was administered with children aged 9 to 12 years. Results were compared with age‐matched healthy children and their mothers. The relationship between anxiety scores of children with CF and their mothers was evaluated by comparing with clinical data of children with CF. At the conclusion of the teleconference, mothers were asked whether their anxiety had changed as a result of the interview.

Results

It was found that healthy children aged 13 to 18 years had higher state anxiety scores than age‐matched children with CF. Mothers of children with CF had higher trait anxiety scores, especially those of children aged 0 to 12 years, than mothers of healthy children (P < .05). For mothers of children with CF, state anxiety scores were higher among those whose children had chronic Pseudomonas infection (P < .05). Most mothers of children with CF stated that their anxiety decreased following the interview.

Conclusion

The COVID‐19 pandemic may increase anxiety among mothers of children with CF as well those with healthy children. However, COVID‐19 had no effect on the anxiety of children with CF. Informing parents of children with CF about COVID‐19 by teleconference may decrease anxiety.
A shift of dynamic equilibrium between the KIT active and inactive states causes drug resistance
Authors: Srikakulam Sanjay K. , Bastys Tomas , Kalinina Olga V.
Published: June 2020

Tyrosine phosphorylation, a highly regulated post‐translational modification, is carried out by the enzyme tyrosine kinase (TK). TKs are important mediators in signaling cascades, facilitating diverse biological processes in response to stimuli. TKs may acquire mutations leading to malignancy and are viable targets for anti‐cancer drugs. Mast/stem cell growth factor receptor KIT is a TK involved in cell differentiation, whose dysregulation leads to various types of cancer, including gastrointestinal stromal tumors, leukemia, and melanoma. KIT can be targeted by a range of inhibitors that predominantly bind to the inactive state of the enzyme. A mutation Y823D in the activation loop of KIT is known to be responsible for the loss of sensitivity to some drugs in metastatic tumors. We used all‐atom molecular dynamics simulations to study the impact of Y823D on the KIT conformation and dynamics and compared it to the effect of phosphorylation of Y823. We simulated in total 6.4 μs of wild‐type, mutant and phosphorylated KIT in the active‐ and inactive‐state conformations. We found that Y823D affects the protein dynamics differently: in the active state, the mutation increases the protein stability, whereas in the inactive state it induces local destabilization, thus shifting the dynamic equilibrium towards the active state, altering the communication between distant regulatory regions. The observed dynamics of the Y823D mutant is similar to the dynamics of KIT phosphorylated at position Y823, thus we hypothesize that this mutation mimics a constitutively active kinase, which is not responsive to inhibitors that bind its inactive conformation.
New Metastable Phase of Bismuth (III) Selenide: Crystal Structure and Electrical Properties
Authors: Serebryanaya Nadezhda , Buga Sergey , Bagramov Rustem , Pahomov Ilya , Eliseev Nikolai , Blank Vladimir
Published: June 2020

Using high‐pressure–high‐temperature treatment at P = 4–7.7 GPa; T = 1373–1473 K with subsequent quenching, a new metastable phase of bismuth selenide (m‐Bi2Se3) is synthesized and its crystal structure, electrical resistivity, and annealing at heating are investigated. Using X‐ray powder diffraction, and analogy with high‐pressure structures of the rare‐earth element sesquichalcogenides, the crystal structure of the new metastable phase of m‐Bi2Se3 is determined as an orthorhombic distorted cation‐deficient structure of the Th3P4 type with the Fdd2 space group and Z = 10.66. The unit‐cell dimensions are: a = 13.4660(7) Å, b = 12.7772(7) Å, c = 9.0896(5) Å. The density of m‐Bi2Se3 (7.47 g cm−3) is slightly less than the initial rhombohedral phase of Bi2Se3, but the coordination number (CN) = 8 is higher than CN = 6 of the initial phase. The period of stability under ambient conditions of the new m‐Bi2Se3 phase is only about 2 months. After 300 °C annealing, m‐Bi2Se3 completely returns to the initial layered structure, and differential scanning calorimetry confirms that the reverse transformation as well as the direct transition occur through an amorphous state. The new phase is a narrow bandgap semiconductor with the energy gap of about 80 meV.
Characterization of maitotoxin‐4 (MTX4) using electrospray positive mode ionization high‐resolution mass spectrometry and UV spectroscopy
Authors: Pisapia Francesco , Sibat Manoëlla , Watanabe Ryuichi , Roullier Catherine , Suzuki Toshiyuki , Hess Philipp , Herrenknecht Christine
Published: June 2020

Rationale

The dinoflagellate genera Gambierdiscus and Fukuyoa are producers of toxins responsible for Ciguatera Poisoning (CP). Although having very low oral potency, maitotoxins (MTXs) are very toxic following intraperitoneal injection and feeding studies have shown they may accumulate in fish muscle. To date, six MTX congeners have been described but two congeners (MTX2 and MTX4) have not yet been structurally elucidated. The aim of the present study was to further characterize MTX4.

Methods

Chemical analysis was performed using liquid chromatography coupled to a diode‐array detector (DAD) and positive ion mode high‐resolution mass spectrometry (LC/HRMS) on partially purified extracts of G. excentricus (strain VGO792). HRMS/MS studies were also carried out to tentatively explain the fragmentation pathways of MTX and MTX4.

Results

The comparison of UV and HRMS (ESI+) spectra between MTX and MTX4 led us to propose the elemental formula of MTX4 (C157H241NO68S2, as the unsalted molecule). The comparison of the theoretical and measured m/z values of the doubly charged ions of the isotopic profile in ESI+ were coherent with the proposed elemental formula of MTX4. The study of HRMS/MS spectra on the tri‐ammoniated adduct ([M – H + 3NH4]2+) of both molecules gave additional information about structural features. The cleavage observed, probably located at C99–C100 in both MTX and MTX4, highlighted the same A‐side product ion shared by the two molecules.

Conclusions

All these investigations on the characterization of MTX4 contribute to highlighting that MTX4 belongs to the same structural family of MTXs. However, to accomplish a complete structural elucidation of MTX4, an NMR‐based study and LC/HRMSn investigation will have to be carried out.
Preparation of Graphene ‐ Like Carbon Composites (GCC) by Hummers Method Using Fly Ash as Carbon Source and Its Removal of Lead from Wastewater
Authors: Shen Huanglin , Xie Wenyu , Zhao Mengqi , Su Zhi , Su Xintai , Lin Zhang
Published: June 2020

In this paper, fly ash (FA) was successfully prepared into graphene‐like carbon composite materials (GCC) with good adsorption properties for heavy metals by alkali activation‐Hummer oxidation method. What's more, the sulfate in the waste liquid can be collected by concentration, and sulfuric acid can be recycled several times after treatment. FA has been fully recycled in an inexpensive and environmentally friendly way. Compared with FA, the specific surface area of GCC increased about 50 times, and the pore size decreased from 9.49 nm to 4.5 nm. The adsorbing amount of GCC could attain 79.38 mg g−1 within 90 min at pH=6. The experimental data of lead adsorption by GCC showed that the results were very consistent with the Freundlich adsorption model. The adsorbent prepared in this work has a good application prospect in water pollution control, which provides a new approach for resource recovery of FA.
Synthesis, Chemotherapeutic Screening and Docking Studies of NSAID Inserted Peptide‐Triazole Hybrid Molecules
Authors: Srinivas Suryapeta , Neeraja Papigani , Naveen Kuntala , Banothu Venkanna , Dubey Pramod K. , Mukkanti Khagga , Pal Sarbani
Published: June 2020

A series of peptide based new tryptophan‐1,2,3‐triazole‐naproxen derivatives were explored as prospective antibacterial / cytotoxic agents. These derivatives were prepared via a multi‐step method involving CuAAC as a key step and characterized by spectral data. The synthesized derivatives were evaluated for their antimicrobial activities against one Gram‐positive (S. aureus) and three Gram‐negative (E. coli, K. pneumoniae and P. vulgaris) bacteria using an agar‐well diffusion protocol where amoxycillin was used as a reference compound. Most of these compounds showed antibacterial activities when tested at 0.4 mg / 50 μl concentration. Compound 9 e i. e. N‐(1‐amino‐1‐oxo‐3‐phenylpropan‐2‐yl)‐3‐(1‐((1‐(2‐((2‐chlorophenyl)amino)‐2‐oxoethyl)‐1H‐1,2,3‐triazol‐4‐yl)methyl)‐1H‐indol‐3‐yl)‐2‐(2‐(6‐methoxynaphthalen‐2‐yl)propanamido)propanamide exhibited good activities against all the strains. The potential DNA gyrase inhibitory activity of this compound was investigated by molecular docking studies carried out using Autodock Vina software. Compound 9 e showed an impressive ΔGbind of −10.0 kcal/mol. The cytotoxicity of the obtained compounds was also assessed against A549 cancer cell line (human lung carcinoma) by an MTT assay. Several of these compounds showed promising activity while 9 e showed lowest IC50 value. A brief SAR for both antibacterial / cytotoxic activities of compounds tested is presented. Overall, compound 9 e has emerged as an initial hit molecule for further study.
Insight into the Alkylation‐Efficiency of Methanol with Toluene over HZSM‐5 Zeolite II: Acidic Properties also Significantly Affects Reacting‐Pathways
Authors: Li Junhui , Gong Qing , Jia Wenzhi , Zhu Xilin , Tang Jia , Cai Jinjun , Zhang Rui , Wang Conghui , Hu Zhonghua , Zhu Zhirong
Published: June 2020

Here the effect of HZSM‐5 acid‐properties on the reacting‐pathways in the reaction system of toluene alkylation with methanol was studied detailedly, from the aspects of acidic type (Brönsted/Lewis), density, strength and location. A reasonable acid‐properties as following is an indispensable support to achieve a high methanol alkylation‐efficiency: not only the relatively high ratios of both Brönsted/Lewis and external/internal acid‐amount, but also both modest density and weak‐medium strength. Firstly, because alone Lewis acidity is almost inactive to aromatic alkylation, meaning Brönsted acid‐sites are indispensable. Secondly, an extremalization in either acidic density or strength is disadvantageous to aromatic alkylation, but encourages the conversion of methanol to olefins (MTO). Besides, the external acid‐sites in a relatively relaxed microenvironment are more favorable to catalyze aromatic‐alkylation than those inside channel where the strong diffusion/space restriction to aromatic‐molecules but foments MTO side‐reaction. Our work may provide a theoretical guidance for improving the methanol alkylation‐efficiency in this reaction system.
‘Off‐the‐Shelf’ Material for Ratiometric Sensing of Phosgene at Nanomolar Level Both in Solution and Gaseous Phase
Authors: Dey Nilanjan
Published: June 2020

Commercially available fluorogenic probe, 2‐ (2‐hydroxyphenyl) benzimidazole has been involved in detecting phosgene via ratiometric color changing response (cyan to blue). Mechanistic studies indicate formation of oxazolidone ring via double carbamylation reaction with phosgene, which significantly curb the extent of excited‐state proton transfer. On the other hand, involvement of weakly alkaline phenolic group as nucleophilic site ensures high specificity over structurally similar competitive analyte, such as triphosgene. Moreover, the present system can detect as low as 14.5 nM phosgene, which is ∼140 fold lower than the threshold value (2 ppm), known to cause immediate danger to health and life (IDLH). Also, detection of phosgene in gaseous state was achieved using dye‐coated paper strips (LOD: ∼0.16 ppm). A quenching in blue fluorescence was noticed when the strips were exposed to phosgene gas phase. Since no sophisticated analytical instrument, trained personnel or constant power supply is required, these paper‐based sensory devices are inexpensive and highly user‐friendly.
Microfluidic Templating of Spatially Inhomogeneous Protein Microgels
Authors: Xu Yufan , Jacquat Raphaël P. B. , Shen Yi , Vigolo Daniele , Morse David , Zhang Shuyuan , Knowles Tuomas P. J.
Published: June 2020

3D scaffolds in the form of hydrogels and microgels have allowed for more native cell‐culture systems to be developed relative to flat substrates. Native biological tissues are, however, usually spatially inhomogeneous and anisotropic, but regulating the spatial density of hydrogels at the microscale to mimic this inhomogeneity has been challenging to achieve. Moreover, the development of biocompatible synthesis approaches for protein‐based microgels remains challenging, and typical gelation conditions include UV light, extreme pH, extreme temperature, or organic solvents, factors which can compromise the viability of cells. This study addresses these challenges by demonstrating an approach to fabricate protein microgels with controllable radial density through microfluidic mixing and physical and enzymatic crosslinking of gelatin precursor molecules. Microgels with a higher density in their cores and microgels with a higher density in their shells are demonstrated. The microgels have robust stability at 37 °C and different dissolution rates through enzymolysis, which can be further used for gradient scaffolds for 3D cell culture, enabling controlled degradability, and the release of biomolecules. The design principles of the microgels could also be exploited to generate other soft materials for applications ranging from novel protein‐only micro reactors to soft robots.
Sedimentation rate of settleable particulate matter in Santiago city, Chile
Authors: Morales‐Casa Verónica , Barraza Francisco , Collante Elizabeth , Ginocchio Rosanna , Jorquera Héctor , Lambert Fabrice , Ospina Esteban , Sáez‐Navarrete César , Varas José
Published: June 2020

Settleable particulate matter (SPM) is an atmospheric pollutant harmful to human health and the environment in high concentrations. Despite this fact, no up‐to‐date information on SPM levels exists for the capital of Chile, Santiago (7 million inhabitants). To address this knowledge gap, SPM sedimentation rates, including soluble and insoluble components, were measured at three different urban sites from July to November of 2016. We compare the measurements with ambient and meteorological information, as well as urban typology settings.

Our results indicate SPM deposition rates between 2.5 and 3.9 g/(m2·30 days). Only one site exceeded the national limit of 4.5 g/(m2·30 days), but we found an increasing trend in all three sites. SPM and its insoluble sedimentation rates increased during warm and dry months and presented significant correlations with meteorological parameters. The highest sedimentation rates were measured at the location with the least permeable surfaces and the lowest green spaces, while the lowest sedimentation rates were found in the sites with abundant green spaces and permeable soil. No significant differences were detected in the soluble components.

Our results suggest that SPM levels in Santiago are close to the national limit and may increase with climate change and urban expansion.
Peste des petits ruminants (PPR) in Africa and Asia: A systematic review and meta‐analysis of the prevalence in sheep and goats between 1969 and 2018
Authors: Ahaduzzaman Md
Published: June 2020

Background

Peste des petits ruminants (PPR) is a prevalent viral disease of sheep and goats that impacts productivity and international animal trade. Despite the substantial economic consequences related to PPR, little is known about the prevalence of this disease at the broad geographical levels.

Objective

The present study aimed to use a systematic approach to assess the regional prevalence of PPR in sheep and goats, and the associated factors that contribute to prevalence estimates.

Methods

Published articles on PPR in sheep and goats were searched in PubMed, Web of Science, Scopus, Google Scholar and the reference lists of articles reporting the prevalence from 1 January 1969 to 31 December 2018. Articles were selected using inclusion and exclusion criteria. Since the heterogeneity among the studies was significant, pooled prevalences were estimated by a random effect meta‐analysis model.

Results

Data on the prevalence of PPR were obtained from Africa and Asia, where the pooled prevalence estimates were 40.99% (95% CI: 37.20%–44.79%) and 38.43% (95% CI: 35.64%–41.22%) respectively. Overall, the estimated pooled prevalence at Africa‐Asia level in sheep was 39.31% (95% CI: 35.75%–42.88%) and in goats was 39.57% (95% CI: 36.66%–42.48%). Significant heterogeneity (I2 > 80%) was noted in most pooled estimates.

Conclusion

The results on the regional prevalence estimates of PPR presented here will be useful in raising awareness and advocating for Governments to engage in initiatives to eradicate PPR and prevent it from spreading to other continents.
Perinatal fluoxetine exposure disrupts the circadian response to a phase-shifting challenge in female rats
Authors: Houwing Danielle J. , de Waard Jolien , Ramsteijn Anouschka S. , Woelders Tom , de Boer Sietse F. , Wams Emma J. , Olivier Jocelien D. A.
Published: June 2020

Rationale

Selective serotonin reuptake inhibitor (SSRI) antidepressants are increasingly prescribed during pregnancy. Changes in serotonergic signaling during human fetal development have been associated with changes in brain development and with changes in affective behavior in adulthood. The suprachiasmatic nucleus (SCN) is known to be modulated by serotonin and it is therefore assumed that SSRIs may affect circadian rhythms. However, effects of perinatal SSRI treatment on circadian system functioning in the offspring are largely unknown.

Objective

Our aim was to investigate the effects of perinatal exposure to the SSRI fluoxetine (FLX) on circadian behavior, affective behavior, and 5-HT1A receptor sensitivity in female rats. In addition, we studied the expression of clock genes and the 5-HT1A receptor in the SCN, as they are potentially involved in underlying mechanisms contributing to changes in circadian rhythms.

Results

Perinatal FLX exposure shortened the free-running tau in response to the 5-HT1A/7 agonist 8-OH-DPAT. However, FLX exposure did not alter anxiety, stress coping, and 5-HT1A receptor sensitivity. No differences were found in 5-HT1A receptor and clock genes Per1, Per2, Cry1, and Cry2 SCN gene expression.

Conclusions

Perinatal FLX exposure altered the response to a phase-shifting challenge in female rats, whether this may pose health risks remains to be investigated.
The Baobab (Adansonia digitata L.) in Southern Kenya–A Study on Status, Distribution, Use and Importance in Taita–Taveta County
Authors: Fischer Sahrah , Jäckering Lisa , Kehlenbeck Katja
Published: June 2020

Baobab (Adansonia digitata L.) is a multipurpose, drought resistant, wild fruit tree, endemic to arid and semi-arid lands of Sub-Saharan Africa. Baobab populations have been showing a lack of regeneration, and therefore causes concern for the species survival. This study investigated the state, distribution and use of baobabs in an under-researched population in Kenya, to identify the potential for further use and development of baobab resources. A baobab population was chosen in Taita–Taveta County, covering a sample area of 2015 km2. A systematic stratified transect survey was done to map baobab distribution using 49 transects (0.5 × 3 km each). The diameter at breast height and other indicators were measured on all baobabs in the transects to assess population status and health. A household survey (n = 46) and focus group discussions (n = 12) were done following the transect survey to gain an idea on the uses and distribution of baobab. In total, 432 baobab trees were measured and recorded in the research area of 2015 km2. The baobabs grew in two clusters (i.e., areas with a baobab density of ≥0.08 baobabs/ha). Both clusters showed rejuvenating populations. The main factors identified by the respondents, positively and negatively influencing baobab distribution were environmental factors, wildlife, human impact and commercial value. The study area shows a great potential for baobab to become an important part of the diet, due to its current use as an emergency food during food scarce times, and the relatively healthy and stable rejuvenating populations.
A novel multi-fidelity modelling-based framework for reliability-based design optimisation of composite structures
Authors: Yoo Kwangkyu , Bacarreza Omar , Aliabadi M. H. Ferri
Published: June 2020

A new multi-fidelity modelling-based probabilistic optimisation framework for composite structures is presented in this paper. The multi-fidelity formulation developed herein significantly reduces the required computational time, allowing for more design variables to be considered early in the design stage. Multi-fidelity models are created by the use of finite element models, surrogate models and response correction surfaces. The accuracy and computational efficiency of the proposed optimisation methodology are demonstrated in two engineering examples of composite structures: a reliability analysis, and a reliability-based design optimisation. In these two benchmark examples, each random design variable is assigned an expected level of uncertainty. Monte Carlo Simulation (MCS), the First-Order Reliability Method (FORM) and the Second-Order Reliability Method (SORM) are used within the multi-fidelity framework to calculate the probability of failure. The reliability optimisation is a multi-objective problem that finds the optimal front, which provides both the maximum linear buckling load and minimum mass. The results show that multi-fidelity models provide high levels of accuracy while reducing computation time drastically.
The clinicopathological and molecular features of sporadic gastric foveolar type neoplasia
Authors: Sugai Tamotsu , Uesugi Noriyuki , Habano Wataru , Sugimoto Ryo , Eizuka Makoto , Fujita Yasuko , Osakabe Mitsumasa , Toya Yosuke , Suzuki Hiromu , Matsumoto Takayuki
Published: June 2020

Gastric intraepithelial foveolar type neoplasia (IEFN) is not well defined. In addition, atrophic mucosa (AM) is an important issue to consider when evaluating gastric tumorigenesis. Here, we assessed the clinicopathological characteristics and molecular alterations contributing to the development of IEFN compared with intestinal type neoplasia. We examined the clinicopathological and molecular features of 42 cases of IEFN with low-grade dysplasia (LGD) and those of 77 cases of intraepithelial intestinal type neoplasia (IEIN) with LGD. The clinicopathological and molecular features examined included the AM status, mucin phenotype expression, CDX2 expression, p53 overexpression, β-catenin intranuclear accumulation, microsatellite instability (MSI), DNA methylation status (low methylation epigenotype [LME], intermediate ME, or high ME), allelic imbalances (AIs), and APC promoter 1B mutations. There were no differences in the frequencies of AM and rates of CDX2 expression between IEFN and IEIN cases. Although no differences in the frequencies of p53 overexpression and MSI were observed between the two histological types, intranuclear expression of β-catenin was significantly higher in IEIN than in IEFN. In addition, although the rate of LME was significantly higher in IEFN cases than in IEIN cases, IEFN was characterized by AIs at multiple foci. Finally, mutation of the APC promoter 1B, which is a characteristic of gastric adenocarcinoma and proximal polyposis of the stomach (potentially resembling IEFN), was detected in only one IEFN case. These findings suggested that IEFN may be an independent entity in terms of molecular alterations including the presence of multiple AIs and LME.
Utilising learning analytics to support study success in higher education: a systematic review
Authors: Ifenthaler Dirk , Yau Jane Yin-Kim
Published: June 2020

Study success includes the successful completion of a first degree in higher education to the largest extent, and the successful completion of individual learning tasks to the smallest extent. Factors affecting study success range from individual dispositions (e.g., motivation, prior academic performance) to characteristics of the educational environment (e.g., attendance, active learning, social embeddedness). Recent developments in learning analytics, which are a socio-technical data mining and analytic practice in educational contexts, show promise in enhancing study success in higher education, through the collection and analysis of data from learners, learning processes, and learning environments in order to provide meaningful feedback and scaffolds when needed. This research reports a systematic review focusing on empirical evidence, demonstrating how learning analytics have been successful in facilitating study success in continuation and completion of students’ university courses. Using standardised steps of conducting a systematic review, an initial set of 6220 articles was identified. The final sample includes 46 key publications. The findings obtained in this systematic review suggest that there are a considerable number of learning analytics approaches which utilise effective techniques in supporting study success and students at risk of dropping out. However, rigorous, large-scale evidence of the effectiveness of learning analytics in supporting study success is still lacking. The tested variables, algorithms, and methods collected in this systematic review can be used as a guide in helping researchers and educators to further improve the design and implementation of learning analytics systems.
Perceptions of Adolescents, Teachers and Parents of Life Skills Education and Life Skills in High School Students in Hong Kong
Authors: Shek Daniel T.L. , Lin Li , Ma Cecilia M.S. , Yu Lu , Leung Janet T.Y. , Wu Florence K.Y. , Leung Hilde , Dou Diya
Published: June 2020

Although theories and research emphasize the importance of adolescent life skills, different stakeholders’ perceptions of the related issues have not been systematically investigated, particularly in Chinese contexts. This paper presents and integrates findings from four studies examining perceptions of different stakeholders on the need for and adequacy of life skills education and perceived adolescent life skills in Hong Kong. Data from four studies were used, including a longitudinal study with senior high school students (N = 3328+) and three cross-sectional studies based on students (N = 2474), teachers (N = 568) and parents (N = 431). Participants responded to measures on their perceptions of the need for life skills education and adequacy of related education in the formal curriculum. They also rated adolescent life skills in different domains, including emotional competence, moral competence, resilience, problem-solving, life meaning, gratefulness, social competence, and integrity. Consistent across the four studies, while many stakeholders regarded life skills as important for adolescents, a majority of them also perceived life skills education as insufficient in the school curriculum. There were also views suggesting that adolescent life skills development was incomplete. Compared with teachers and parents, adolescents perceived higher levels of life skills in themselves and adolescents in Hong Kong. There is a strong perceived need to step up life skills education in adolescents, particularly in Hong Kong.