bluuebunny/crossref_metadata_2025 huggingface dataset:
Gestational diabetes mellitus: prevalence, risk factors, maternal and infant outcomes
Authors: Xiong X. , Saunders L.D. , Wang F.L. , Demianczuk N.N.
Published: July 2002

Objectives: To study prevalence, risk factors, and maternal and infant outcomes of women with gestational diabetes mellitus (GDM). Methods: A retrospective cohort study was performed based on 111 563 pregnancies delivered between 1991 through 1997 in 39 hospitals in northern and central Alberta, Canada. Multivariate logistic regression was used to estimate the odds ratios with 95% confidence intervals, and to control for confounding variables. Results: The prevalence of GDM was 2.5%. Risk factors for GDM included age >35 years, obesity, history of prior neonatal death, and prior cesarean section. Teenage mothers and women who drank alcohol were less likely to have GDM. Mothers with GDM were at increased risk of presenting with pre‐eclampsia, premature rupture of membranes, cesarean section, and preterm delivery. Infants born to mothers with GDM were at higher risk of being macrosomic or large‐for‐gestational‐age. Conclusions: Specific conditions predispose to GDM which itself is associated with a significantly increased risk of maternal and fetal morbidity.
The maternity waiting home concept: the Nsawam, Ghana experience
Authors: Wilson J.B , Collison A.H.K , Richardson D , Kwofie G , Senah K.A , Tinkorang E.K ,   (The Accra PMM Team)
Published: July 2002

Preliminary studies: Focus group discussions with community members in Nsawam District, Ghana, identified poor roads, scarce transport and exorbitant fees for emergency transport as barriers to reaching the district hospital for treatment of an obstetric complication. Interventions: To minimize delay in the event of a complication, a maternity waiting home (MWH) was established in Nsawam in 1994. One ward of an abandoned hospital was renovated and furnished for this purpose. The objective was to encourage women at high risk of obstetric complications to move to the MWH so they could be transferred to the hospital when labor began. Results: Of 25 women referred to the MWH by health personnel over 12 months, only one complied, for one night. Focus group discussions with community members and hospital staff later revealed that cost and hardship of staying away from home, absence of health personnel, distance from hospital, desolate surroundings and lack of perceived need were reasons for poor utilization. Costs: The intervention cost approximately US $10 500, shared approximately equally between the project and government. The main government contribution was the building. Conclusions: It is important to consult potential users not only to identify problems, but also to identify appropriate solutions. Careful ‘market research’ should be done before launching interventions. © 1997 International Federation of Gynecology and Obstetrics
Mobilizing transport for obstetric emergencies in northwestern Nigeria
Authors: Shehu D , Ikeh A.T , Kuna M.J ,   (The Sokoto PMM Team)
Published: July 2002

Preliminary studies: Focus group discussions and a village case study in Kebbi State revealed delay in the transport of women with obstetric complications. Among contributing factors identified were shortages of vehicles and fuel, and unwillingness of drivers to transport women at affordable fares. Interventions: The cooperation of the local transport workers union was enlisted to address the situation. In 1993, drivers were sensitized and trained and a revolving emergency fuel fund was established. Prior to these activities, emergency obstetric services at nearby facilities had been upgraded. Results: Over two years, 29 women with obstetric complications were transported. Of these, only one died. Mean cost of transport to patients was US $5.89. Mean time from the onset of complications to treatment was 9 h. Substantial numbers of non‐obstetric patients in need of emergency care were also transported. Although defaulting eventually resulted in depletion of the fuel fund, the reimbursement system had become sufficiently well‐established that most drivers no longer requested funds in advance. Costs: Cost of the transport intervention was US $268, with 72% coming from project funds. Conclusions: Improving transport to emergency care does not necessarily require ambulances. Commercial transport owners and communities can be mobilized to provide affordable emergency transport for women with complications. © 1997 International Federation of Gynecology and Obstetrics
Manufacturing strategy in context: environment, competitive strategy and manufacturing strategy
Authors: Ward Peter T , Duray Rebecca
Published: July 2002

Considering manufacturing strategy in its larger strategic context has been thematic in conceptual literature in operations but relatively neglected in empirical studies, thus leaving predominant conceptual models of manufacturing strategy largely untested. This research develops a conceptual model of manufacturing strategy from the literature and tests the model using data from a sample of manufacturers in three industries in the United States. This research contributes to manufacturing strategy literature in four ways. First, it supports empirically a model of manufacturing strategy that is predominant in the conceptual literature. Second, it demonstrates that the strategic linkages in manufacturing businesses are clearer among good performers than poor performers. Third, this research suggests that competitive strategy acts as a mediator between an organization's environment and its manufacturing strategy. Fourth, the findings suggest that the relationship between competitive strategy and performance is mediated by manufacturing strategy. These last two findings have important implications for approaching research in manufacturing strategy in the future.
Opposite transitions of chick brain catalytically active cytosolic creatine kinase isoenzymes during development
Authors: Ramı́rez Oscar , Jiménez Esperanza
Published: July 2002

Postnatally the rat brain synthesizes catalytic forms of muscle type (MM) and heart type (MB) creatine kinase (CK), besides the supposedly sole type vertebrate brain‐specific (BB) CK. We intended to demonstrate that in Rhode Island chicken brain, cytosolic (c) CK isoenzymatic transitions, (for example BB–CK is followed by the appearance of MB–CK and MM–CK during muscle differentiation), can also occur during development and aging. Cytosolic post 125 000×g, mitochondrial CK‐free, brain samples were obtained for zone electrophoresis separation and identification of catalytically active cCK isoforms. BB–CK was never found during chicken brain ontogeny. Against the accepted view, an opposite isoenzyme transition pattern from MM through BB–CK was found in the chicken embryonic brain from the very early stages of development up to day 2 post‐hatching. At very early stages of chicken brain ontogeny constitutive MM– and MB–CK isoenzymes were present before the advent of creatine. It seems to be that typical and atypical brain MM– and MB–CK could be working as ATPases in the absence of creatine before embryonic stage 28 (day 5.5) and/or such CK isoforms may begin to form part of the slow component b in developing early neurons and later in the nuclei of glial cells to be used by the CK/phosphocreatine (PC) system as the neural tissues mature. The post‐hatching transition pattern showed simultaneous expression of more than one CK isoenzyme within the same neural sample as in post‐natal rat brain, presumably due to regional differential transphosphorylation requirements. Strain‐dependent enzymatic specific activities have been reported in several species. Since equivalent values of brain CK specific activity were obtained previously from the embryonic plateau phase of CK activity during White Leghorn development, and those from Rhode Island brain neurons cultured 11 days, we compared if, in vivo, a similar brain CK specific activity pattern was physiologically equivalent during Rhode Island and White Leghorn chicken ontogeny. We found quantitatively different strain‐specific CK specific activity patterns during this period. Rhode Island brain CK activity values were approximately 4.5‐fold those of White Leghorn ones. This indicates that production of energy from anaerobic metabolism and transphosphorylation by the CK/PC system to synthesize ATP more efficiently is strain‐specific. In Rhode Islands, there was an age‐dependent increase of CK specific activity, mostly in older animals (440% above the value found during the embryonic plateau), when the Krebs cycle and glycolysis lose capacity. During adult life and aging, under physiological conditions, the three CK isoenzymes may participate in diverse functions of the different cell compartments of brain glia and neurons with regard to their high and fluctuating energy demands that are not completely covered by anaerobic and aerobic glycolisis.
Thyroid hormone action on astroglial cells fromdistinct brain regions during development
Authors: Lima Flávia Regina Souza , Gonçalves Nelcy , Gomes Flávia CarvalhoAlcantara , De Freitas Marta Sampaio , Neto Vivaldo Moura
Published: July 2002

Astrocytes are target to triiodothyronine (T3) hormone action during rat braindevelopment. In this work, we show that astrocytes from distinct developing brain regions aredifferently responsive to thyroid hormone. Distinctly from embryonic or newborn cerebralhemisphere and mesencephalic astrocytes, newborn cerebellar and embryonic hippocampalastrocytes do not change their morphology in response to hormone treatment. We also analysedprotein synthesis and secretion from these T3‐treated astrocytes. The results showed a significantincrease in protein synthesis in astrocytes from older brain regions. Maximum effect, however,was observed in cerebral hemisphere astrocytes from newborn rats. The protein secretion effectwas also more evident in the cerebral hemisphere as well as in cerebellar astrocytes fromnewborn rats. In addition, we examined T3 effects on GFAP/vimentin expression by culturing6‐day old cerebellar astrocytes. In this case T3 seems to induce GFAP expression which might beoccurring as a first step to astrocyte differentiation.
Pedf (Pigment epithelium‐derived Factor) promotes increase and maturation of pigment granules in pigment epithelial cells in neonatal albino rat retinal cultures
Authors: Malchiodi‐albedi F. , Feher J. , Caiazza S. , Formisano G. , Perilli R. , Falchi M. , Petrucci T.C. , Scorcia G. , Tombran‐tink J.
Published: July 2002

Pigment Epithelium‐Derived Factor (PEDF), purified from human retinal pigment epithelial (RPE) cell culture medium, is a neurotrophic factor which potentiates the differentiation of human Y‐79 retinoblastoma cells and increases the survival of cerebellar granule cells. To investigate the effects of PEDF on non‐transformed retinal cells, we used primary cultures of neonatal albino rat retinas, where the three principal cell types of the retinal layers (neuronal, glial and epithelial) were all present and focussed our attention on RPE cells, which are of special relevance for retinal pathophysiology. PEDF had a dramatic effect on these cells. They showed a modified phenotype, with larger dimensions, higher cytoplasmic spreading, presence of phagocytic vacuoles, development of wide intercellular contacts, and increase and maturation of pigment granules. These results suggest that PEDF may have a role in regulating RPE cell differentiation.
Developmental regulation of glutamate transporters and glutamine synthetase activity in astrocyte cultures differentiatedin vitro
Authors: Stanimirovic Danica B. , Ball Rita , Small Daniel L. , Muruganandam Arumugam
Published: July 2002

Glutamate plays an important role in brain development, physiological function, and neurodegeneration. Astrocytes control synaptic concentration of glutamate via the high affinity glutamate transporters, GLT‐1 and GLAST, and the glutamate catabolizing enzyme, glutamine synthetase. In this study we show that astrocytes cultured from rat brain in various stages of development including embryonic (E18), postnatal (P1–P21) and mature (P50), show distinct patterns of GLT‐1 and GLAST expression, glutamine synthetase activity, and phenotypic changes induced by dibutyryl‐cyclic adenosine monophosphate. The transcripts for GLT‐1 message were detectable in embryonic astrocytes only, whereas the GLAST message was highly expressed in E18 and P1–P4 astrocyte cultures, declined in P10–P21, and was undetectable in P50 astrocytes. Uptake of3H‐glutamate correlated well with GLAST expression in astrocyte cultures of all developmental stages. Glutamine synthetase activity significantly declined from high embryonic levels in P4 astrocytes and remained low throughout postnatal maturation. Exposure of astrocyte cultures to the differentiating agent, db‐cAMP (250–500 μM; 6 days), resulted in a pronounced stellation, up‐regulation of GLT‐1 and GLAST in E18, and GLAST in P4 cultures, while it was ineffective in P10 astrocytes. By contrast, db‐cAMP induced a more pronounced stimulation of glutamine synthetase activity (up to 10‐fold above basal) in P10 than in E18 cultures (up to 2 times above basal). The differences in expression/inducibility of glutamate transporters and glutamine synthetase observed in astrocyte cultures derived from various stages of fetal and postnatal development suggest that astrocytes in vivo might also respond differently to environmental or injurious stimuli during development and maturation.
Gender differences in panic disorder symptoms and illicit drug use among young people in Hungary
Authors: Kecskés I. , Rihmer Z. , Kiss K. , Sárai T. , Szabó A. , Kiss G.H.
Published: July 2002

The authors have investigated the frequency of illicit drug use, and spontaneous and drug-provoked panic disorder symptoms in Hungarian youths. A semi-structured self-reporting questionnaire (with questions about drug usage and the persistence of some DSM-IV panic disorder symptoms) was filled out in discos/nightclubs, secondary schools and universities. Almost 17% of the total sample (n = 1298) reported on illicit drug-use at least once in their life, and this rate was significantly higher among males. Regardless of the illegal drug use 14.6% of the total sample reported on four or more DSM-IV symptoms of panic disorder, and this rate was significantly higher among females. Analyzing the panic disorder symptoms only among drug-users (n = 219), the frequency of persons with four or more anxiety symptoms was 14.1% before drug use, and it increased to 30.6% during the period of drug use (P < 0.001). The findings support previous results showing (i) higher prevalence of anxiety symptoms among females; (ii) higher rate of illicit drug use among males; and (iii) a possible anxiety-provoking effect of illicit drugs.
Epidemiology of heart failure in Sweden — a national survey
Authors: Mejhert Märit , Persson Hans , Edner Magnus , Kahan Thomas
Published: July 2002

Background:

In Sweden heart failure is the most frequent discharge diagnosis within internal medicine. The prevalence of heart failure seems to be increasing, mainly due to an ageing population, but also because of improved survival in patients with cardiovascular diseases.

Aim:

To describe the epidemiology of heart failure in Sweden from a perspective based on demographic and health care data.

Methods:

The national registers in Sweden provide detailed information on health care consumption in relation to different diagnoses. Pharmaceutical sales are also registered. There are national epidemiological reports, reports on health care utilization and on health economics concerning heart failure patients.

Results:

There has been structural changes in the Swedish health care system due to financial restraints in the health care budget. Aiming at reducing hospital costs, the total amount of hospital beds has been cut down markedly during the last decade. The number of heart failure patients and the number of hospital stays have increased during the same period. Hospital stays have become shorter. The number of patients and hospital stays more than double when heart failure as both primary and secondary discharge diagnoses are included.

Conclusion:

The available national registers provide a good opportunity to study epidemiology of heart failure in Sweden. The number of hospital beds has decreased markedly within the last decade due to changes in the Swedish health care system. Nevertheless, there has been an increase in the number of patients discharged with heart failure from the hospitals, suggesting an increase in prevalence.
How patients with heart failure are managed in the United Kingdom
Authors: English K.M. , Channer K.S.
Published: July 2002

Heart failure is a major cause of morbidity and mortality worldwide. In the UK it is estimated to affect one in ten octogenarians. This obviously imposes a large burden on our health care services, and the ageing of our population will only exacerbate this. In this article we have attempted to provide a general overview of the day to day management of these patients in the United Kingdom.
Identification of two subtilisin‐like serine proteases engaged in the degradation of recombinant proteins in Nicotiana benthamiana
Authors: Puchol Tarazona Alejandro A. , Maresch Daniel , Grill Annette , Bakalarz Janet , Torres Acosta Juan A. , Castilho Alexandra , Steinkellner Herta , Mach Lukas
Published: December 2020

The tobacco variant Nicotiana benthamiana has recently emerged as a versatile host for the manufacturing of protein therapeutics, but the fidelity of many recombinant proteins generated in this system is compromised by inadvertent proteolysis. Previous studies have revealed that the anti‐HIV‐1 antibodies 2F5 and PG9 as well as the protease inhibitor α1‐antitrypsin (A1AT) are particularly susceptible to N. benthamiana proteases. Here, we identify two subtilisin‐like serine proteases (NbSBT1 and NbSBT2) whose combined action is sufficient to account for all major cleavage events observed upon expression of 2F5, PG9 and A1AT in N. benthamiana. We propose that downregulation of NbSBT1 and NbSBT2 activities could constitute a powerful means to optimize the performance of this promising platform for the production of biopharmaceuticals.

Databases

NbSBT sequence data are available in the DDBJ/EMBL/GenBank databases under the accession numbers MN534996 to MN535005.
Carbon Nanomaze for Biomolecular Detection with Zeptomolar Sensitivity
Authors: Bao Jing , Qiu Xiaopei , Wang Deqiang , Yang Huisi , Zhao Jiaying , Qi Yanli , Zhang Liangliang , Chen Xiaohui , Yang Mei , Gu Wei , Huo Danqun , Luo Yang , Hou Changjun
Published: December 2020

Despite numerous efforts, the accurate determination of trace biomolecules with zeptomolar sensitivity remains elusive. Here, a 3D carbon nanomaze (CAM) electrode for the ultrasensitive detection of trace biomolecules such as nucleic acids, proteins, and extracellular vesicles is reported. The CAM electrode consists of an interlaced carbon fiber array on which intercrossed graphene sheets are vertically tethered in situ, permitting local confinement of trace molecules to increase molecular hybridization efficiency. Furthermore, a self‐assembled DNA tetrahedron array adopts a rigid spatial conformation to guarantee the controllable arrangement of immobilized biological probes, facilitating analytical sensitivity and reproducibility. In a proof‐of‐concept experiment on detecting microRNA‐155, a linearity of 0.1 aM to 100 nM and a sensitivity of 0.023 aM (23 zM) are achieved. With the optimal parameters, the proposed nanoelectrode demonstrates encouraging consistency with quantitative real‐time polymerase chain reaction during clinical sample detection. Through simple functionalization by appending various biomolecular probes of interest, the developed CAM platform with ultrahigh sensitivity can be exploited as a versatile tool in environmental, chemistry, biology, and healthcare fields.
Identifying Ionic and Electronic Charge Transfer at Oxide Heterointerfaces
Authors: Rose Marc‐André , Šmíd Břetislav , Vorokhta Mykhailo , Slipukhina Ivetta , Andrä Michael , Bluhm Hendrik , Duchoň Tomáš , Ležaić Marjana , Chambers Scott A. , Dittmann Regina , Mueller David N. , Gunkel Felix
Published: December 2020

The ability to tailor oxide heterointerfaces has led to novel properties in low‐dimensional oxide systems. A fundamental understanding of these properties is based on the concept of electronic charge transfer. However, the electronic properties of oxide heterointerfaces crucially depend on their ionic constitution and defect structure: ionic charges contribute to charge transfer and screening at oxide interfaces, triggering a thermodynamic balance of ionic and electronic structures. Quantitative understanding of the electronic and ionic roles regarding charge‐transfer phenomena poses a central challenge. Here, the electronic and ionic structure is simultaneously investigated at the prototypical charge‐transfer heterointerface, LaAlO3/SrTiO3. Applying in situ photoemission spectroscopy under oxygen ambient, ionic and electronic charge transfer is deconvoluted in response to the oxygen atmosphere at elevated temperatures. In this way, both the rich and variable chemistry of complex oxides and the associated electronic properties are equally embraced. The interfacial electron gas is depleted through an ionic rearrangement in the strontium cation sublattice when oxygen is applied, resulting in an inverse and reversible balance between cation vacancies and electrons, while the mobility of ionic species is found to be considerably enhanced as compared to the bulk. Triggered by these ionic phenomena, the electronic transport and magnetic signature of the heterointerface are significantly altered.
Designing Mechanical Metamaterials with Kirigami‐Inspired, Hierarchical Constructions for Giant Positive and Negative Thermal Expansion
Authors: Guo Xiaogang , Ni Xiaoyue , Li Jiahong , Zhang Hang , Zhang Fan , Yu Huabin , Wu Jun , Bai Yun , Lei Hongshuai , Huang Yonggang , Rogers John A. , Zhang Yihui
Published: December 2020

Advanced mechanical metamaterials with unusual thermal expansion properties represent an area of growing interest, due to their promising potential for use in a broad range of areas. In spite of previous work on metamaterials with large or ultralow coefficient of thermal expansion (CTE), achieving a broad range of CTE values with access to large thermally induced dimensional changes in structures with high filling ratios remains a key challenge. Here, design concepts and fabrication strategies for a kirigami‐inspired class of 2D hierarchical metamaterials that can effectively convert the thermal mismatch between two closely packed constituent materials into giant levels of biaxial/uniaxial thermal expansion/shrinkage are presented. At large filling ratios (>50%), these systems offer not only unprecedented negative and positive biaxial CTE (i.e., −5950 and 10 710 ppm K−1), but also large biaxial thermal expansion properties (e.g., > 21% for 20 K temperature increase). Theoretical modeling of thermal deformations provides a clear understanding of the microstructure–property relationships and serves as a basis for design choices for desired CTE values. An Ashby plot of the CTE versus density serves as a quantitative comparison of the hierarchical metamaterials presented here to previously reported systems, indicating the capability for substantially enlarging the accessible range of CTE.
Sonolithography: In‐Air Ultrasonic Particulate and Droplet Manipulation for Multiscale Surface Patterning
Authors: Shapiro Jenna M. , Drinkwater Bruce W. , Perriman Adam W. , Fraser Mike
Published: December 2020

Acoustic fields are increasingly being used in material handling applications for gentle, noncontact manipulation of particles in fluids. Sonolithography is based on the application of acoustic radiation forces arising from the interference of ultrasonic standing waves to direct airborne particle/droplet accumulation in defined spatial regions. This approach enables reliable and repeatable patterning of materials onto a substrate to provide spatially localized topographical or biochemical cues, structural features, or other functionalities that are relevant to biofabrication and tissue engineering applications. The technique capitalizes on inexpensive, commercially available transducers and electronics. Sonolithography is capable of rapidly patterning micrometer to millimeter scale materials onto a wide variety of substrates over a macroscale (cm2) surface area and can be used for both indirect and direct cell patterning.
Occurrence of nitrosamines and their precursors in North American drinking waters
Authors: Krasner Stuart W. , Roback Shannon , Qian Yichao , Li Xing‐Fang , Marfil‐Vega Ruth , Bukhari Zia
Published: December 2020

Eight N‐nitrosamines were measured at 37 water plants in the United States and Canada. Five tobacco‐specific nitrosamines (TSNAs) were measured in selected waters. N‐Nitrosodimethylamine (NDMA) was preferentially formed in chloraminated systems (maximum detention time: median 4.4 ng/L). A small amount was detected in some chlorinated systems (90th percentile <2.0 ng/L). After ozone (before chloramines), NDMA was sometimes detected (90th percentile 2.9 ng/L), suggesting that the ozone did not react with precursors to form NDMA. The chloramine plants that temporarily switched to chlorine typically produced less NDMA (Plant 29 reduced NDMA formation, on average, from 34 to 4 ng). More NDMA was produced during spring runoff, when there were elevated levels of ammonia and NDMA precursors in the source water. More NDMA was formed when there were higher levels of poly(diallyldimethylammonium chloride) (polyDADMAC) used. N‐Nitrosomorpholene was found to be a contaminant and not a disinfection byproduct; it did not increase during chloramination. TSNAs were produced during spring runoff; source water ammonia impacted the chlor(am)ine chemistry.
Virgibacillus dokdonensis VITP14 produces α‐amylase and protease with a broader operational range but with differential thermodynamic stability
Authors: Mishra Satabdi , Joghee Nidhya Nadarajan , Jayaraman Gurunathan
Published: December 2020

Extracellular α‐amylase and protease were coproduced from halo tolerant Virgibacillus dokdonensis VITP14 with banana peels (2% w/v) as substrate. The pH optima for α‐amylase and protease were 6.5 and 7.0, respectively. The temperature optima of α‐amylase and protease were 30 and 50 °C, respectively. Both the enzymes were active in the presence of various metal ions (1 mM of Ni2+, Ca2+, Ba2+, Sr2+, and Mg2+), detergents (Tween 20, Tween 80, Triton X‐100), and other additives (2‐mercaptoethanol and urea). Both the enzymes followed Michaelis–Menten type enzyme kinetics with Vmax of 121.40 and 4.17 μmol Min−1 mL−1 and Km of 0.59 and 0.28 mg mL−1 for amylase and protease, respectively. Amylase showed higher activation energy for inactivation (75.55 kJ mol−1 compared to 59.70 kJ mol−1 for protease) and higher thermal stability (reflected by longer half‐life 53.23 Min compared to 0.11 Min for protease) at 60 °C. The coexistence of amylase and protease could be attributed to the difference in the optimum temperatures of activity and thermal stability of the two enzymes.
A rare case of acquired factor V inhibitor, during treatment with dabigatran for chronic atrial fibrillation, successfully treated with bypassing agents
Authors: Giuffrida Gaetano , Markovic Uros , Nicolosi Daniela , Calafiore Valeria
Published: December 2020

Acquired factor V inhibitor represents a rare condition, described only in case reports. The use of activated bypassing agents in bleeding control could be of aid and improve the survival in symptomatic patients with acquired factor V inhibitor.
Energy Generation and Iron Removal in Batch and Continuous Single‐Chamber Microbial Fuel Cells
Authors: Sumisha Anappara , Haribabu Krishnan
Published: December 2020

Energy generation was studied in a membraneless single‐chamber microbial fuel cell (SCMFC) with batch and continuous systems, using iron(III) as electron acceptor at the cathode and Shewanella putrefaciens as the biocatalyst. A maximum stable voltage of 0.769 V was achieved at a maximum tolerable concentration (MTC) of 50 ppm Fe for the batch mode of operation. A metal removal efficiency of 91.1 % and a total organic carbon removal of 85.5 % were obtained at the MTC. Also, the effects of various hydraulic retention times (HRT) were tested for the continuous process. A maximum voltage of 0.81 V was observed during operation for 13 h of HRT, along with a substrate degradation of 91.8 % and an iron removal of 86.4 %.
Flow Synthesis of 2‐[Methyl(pyridin‐2‐yl)amino]ethanol: An Experimental and Computational Study
Authors: Cuesta Calvo Paulo Victor , Rodrigues Batista Patrick , Rodrigues de Oliveira Silva Renan , Converti Attilio , Al Arni Saleh , Solisio Carlo , Ducati Lucas C. , Alves Palma Mauri Sergio
Published: December 2020

Microreactor technology is increasingly applied in the chemical‐pharmaceutical industry for safer and more efficient drug production as compared to the traditional batch process. This technology is employed for the first time to study the production of 2‐[methyl(pyridin‐2‐yl)amino]ethanol, the first intermediate in rosiglitazone synthesis. Under the optimum operating conditions, a single microreactor chip at 160 °C allowed to produce the equivalent of more than five batch reactors at 120 °C. The kinetic study indicated that the reaction is second order. Thermodynamic parameters were determined by the Eyring equation and density functional theory (DFT) calculations with good agreement. DFT results suggested a concerted nucleophilic aromatic substitution reaction mechanism.
Assessment of salivary thioredoxin levels in oral lichen planus and oral squamous cell carcinoma
Authors: Amirchaghmaghi Maryam , Mahfoozi Roya , Dalirsani Zohreh , Mostaan Leila Vazifeh , Hashemy Seyed Isaac , Shakeri Mohammad Taghi
Published: December 2020

Objective

Oral lichen planus (OLP) is a chronic mucocutaneous inflammatory disease, which is considered as a potentially malignant condition and could transformed into oral squamous cell carcinoma (OSCC). Squamous cell carcinmoma is the most common oral cancer. This study aimed to compare salivary thioredoxin levels as an antioxidant protein among patients with OSSC, OLP and healthy subjects.

Materials and methods

Twenty‐eight patients with OLP, 20 patients with OSCC and 40 healthy people enrolled in this observational study. Saliva samples were collected from all subjects and salivary thioredoxin levels were evaluated by Elisa test. The data were recorded in the check lists and analyzed using SPSS (ver.17).

Results

Thioredoxin levels of healthy controls were insignificantly higher than OLP and SCC patients (p = 0.135). There was a statistically remarkable indirect relationship between thioredoxin levels and severity of the lesions determined by Thongprasom criteria among OLP patients. The thioredoxin concentration was significantly higher in the keratotic OLP. Among the OSCC patients, the highest levels of thioredoxin were found among patients aged more than 65 years. Salivary thioredoxin levels based on other variables were not significantly different between the studied groups.

Conclusion

In this study, there was not any significant difference between salivary thioredoxin levels in the OLP and OSCC patients, though it was unremarkable higher in the healthy group compared to the patients; therefore, the role of thioredoxin in the cellular oxidation–reduction status could be suggested; however, further studies are recommended.
Efficient portfolio construction by means of CVaR and k‐means++ clustering analysis: Evidence from the NYSE
Authors: Soleymani Fazlollah , Vasighi Mahdi
Published: December 2020

The major target of this article is to build a machine learning model furnishing an efficient and quick analysis for a large portfolio of stocks. Towards constructing such an efficient portfolio, we employ the Value‐at‐Risk (VaR) and Conditional Value‐at‐Risk (CVaR) as tools of well‐consolidated use for controlling the anomalies' presence of potential danger to the financial stability of the portfolio. It is shown how the well‐resulted k‐means++ clustering technique is employed to cluster financial returns for the stocks of a system and then the risk measures of VaR and CVaR are obtained for the clusters to find the most and least riskiest groups of stocks. The proposed procedure is fast for clustering a financial large set of data by providing many features for each cluster.
Estimating price impact via deep reinforcement learning
Authors: Cao Yi , Zhai Jia
Published: December 2020

Price impact is the adverse change of the asset price against trader's action. As a crucial part of the indirect trading cost, price impact has attracted increasing attention in both econometric and data science literature. In this paper, we draw upon both strands of the literature and develop a deep neural network enhanced recursive (DeRecv) model to estimate temporary and permanent price impact of an order or trade. The temporary price impact is calculated as the sum of the expected immediate impact at each time point after taking action in an ad hoc market condition. The permanent price impact is defined as a new permanent level at which the information of the incoming order is entirely absorbed by the market. Through the experimental evaluation based on data from 10 stocks at NASDAQ and Shanghai Stock Exchange, we show that the proposed DeRecv model is better than the reinforcement learning model and the traditional vector autoregressive model.
Interannual variations of monthly precipitation and associated mechanisms over the Three River Source region in China in winter months
Authors: Wang Teng , Sun Bo , Wang Huijun
Published: December 2020

This study investigates the interannual variability of winter precipitation over the Three River Source (TRS) region in China based on precipitation observations collected at stations in the TRS region and reanalysis datasets for the period of 1980–2015. The results suggest that the TRS winter precipitation has distinct interannual variability with discordant trends in different months, that is, an increasing trend is found in November and February, a decreasing trend is found in other winter months, and interannual variations in precipitation are different in different months. The mechanisms for the interannual variation in monthly precipitation over the TRS region are significantly different in different winter months. The interannual variability of TRS precipitation in November is modulated by an anomalous westerly water vapour transport (WVT) branch. This anomalous WVT branch is related to a North Atlantic‐Europe‐Tibetan Plateau (NA‐E‐TP) wave‐train that originates in the North Atlantic due to the ocean–atmosphere interaction. In December, a circum‐global teleconnection (CGT) wave‐train can induce anomalous westerly WVT in the TRS region, resulting in increased precipitation there. This CGT wave‐train is triggered by warm SST anomalies in the central‐eastern tropical Pacific associated with the El Niño‐Southern Oscillation (ENSO). The interannual variability of TRS precipitation in January and February is affected by southwesterly WVT anomalies over the TRS region, which are associated with a southeastward propagating wave‐train over Eurasia caused by the North Atlantic Oscillation (NAO). In March, the interannual variability of TRS precipitation is modulated by the leading mode of the Eurasian circulation that resembles the Scandinavian (EU1) pattern, which can cause anomalous southwesterly WVT in the TRS region. In winter, the characteristics of sea surface temperature anomalies, weather systems, and atmospheric circulations associated with interannual variations of monthly precipitation in the TRS region are different for individual winter months.
Calibration of Raman bandwidth in large Raman images using a mercury–argon lamp
Authors: Jakubek Ryan S. , Fries Marc D.
Published: December 2020

Raman imaging has proven to be an important tool in the analysis of astromaterials. Raman imaging can describe the composition and mineralogy of astromaterials in a nondestructive manner preserving precious samples for additional study. Raman bandwidth is a common spectroscopic marker used to elucidate information such as composition, latent strain, and thermal processing history. The observed Raman bandwidth of a sample is a result of a convolution of the true Raman lineshape and the spectrometer's slit function. Thus, to compare Raman bandwidths across spectra and instruments, one needs to calibrate the Raman spectrum to account for effects of the slit function. Astromaterials are heterogeneous requiring the collection of large Raman images for adequate sampling. It is well known that the wavenumber calibration of an instrument drifts with time throughout Raman image collection. Here, we find that the spectrometer slit function also varies with time and laboratory temperature throughout Raman image collection. We utilize a mercury–argon (Hg–Ar) lamp integrated into our Raman microscope in a novel manner to calibrate the bandwidth in each Raman spectrum within our Raman image. We can do this because the narrow Hg–Ar lamp emission lines approximate the spectrometer slit function for each Raman spectrum allowing for the calculation of the true Raman bandwidth from each Raman spectrum within the Raman image. Our technique allows for the comparison of Raman bandwidth throughout a Raman image and between Raman images/spectra collected using different instruments, facilitating scientific analyses that are reproducible across multiple laboratories.
Perceptual Voice and Speech Analysis after Supraglottic Laryngeal Closure for Chronic Aspiration in Head and Neck Cancer
Authors: Ku Peter K. M. , Vlantis Alexander C. , Yeung Zenon W. C. , Ho Osan Y. M. , Cho Ryan H. W. , Lee Alex K. F. , Hui Thomas S. C. , So Erin P. L. , Law Thomas K. T. , Abdullah Victor , van Hasselt Andrew , Tong Michael C. F.
Published: December 2020

Objectives/Hypothesis

To evaluate the voice and speech outcomes after tubed supraglottic laryngeal closure (TSLC) surgery to treat chronic aspiration after radiotherapy for head and neck cancer.

Study Design

A retrospective case‐control study.

Methods

The data of patients who underwent radiotherapy for head and neck cancer and who later required total laryngectomy or TSLC for chronic aspiration between 2004 and 2017 were retrieved from a dysphagia clinic. Preoperative and postoperative voice and speech were assessed by the GRBAS and INFVo rating scales. Control subjects who underwent radiotherapy alone or total laryngectomy with a tracheoesophageal prosthesis for other indications were recruited for comparison.

Results

Of 15 patients who underwent a TSLC with a mean age of 57.3 years (45–75 years), 13 were male and 2 female. All patients had a history of nasopharyngeal carcinoma. The success rate of speech production using their own larynx following an intact TSLC was 64%. There was no statistically significant difference in voice and speech ratings between preoperative and TSLC subjects on the GRBAS (P = .32) and INFVo scales (P = .57), although the quality of voice appeared to deteriorate after TSLC. However, the INFVo scale for impression, intelligibility and unsteadiness of the voice after TSLC was statistically significantly better than for laryngectomy with tracheoesophageal speech.

Conclusions

A tubed supraglottic laryngeal closure controls chronic aspiration while preserving the larynx for phonation, and results in a better voice and speech quality than a laryngectomy with a voice prosthesis.

Level of Evidence

4 Laryngoscope, 131:E1616–E1623, 2021
Olfactory and taste dysfunction among mild‐to‐moderate symptomatic COVID‐19 positive health care workers: An international survey
Authors: Andrews Peter J. , Pendolino Alfonso Luca , Ottaviano Giancarlo , Scarpa Bruno , Grant Joseph , Gaudioso Piergiorgio , Bordin Anna , Marchese‐Ragona Rosario , Leoni Davide , Cattelan Annamaria , Kaura Anika , Gane Simon , Hamilton Nick J. , Choi David , Andrews Julie A.
Published: December 2020

Objectives

To determine the prevalence of olfactory and taste dysfunction (OD; TD) among COVID‐19 positive health care workers (HCWs), their associated risk factors and prognosis.

Methods

Between May and June 2020, a longitudinal multicenter study was conducted on symptomatic COVID‐19 PCR confirmed HCWs (COVID‐19 positive) in London and Padua.

Results

Hundred and fourteen COVID‐19 positive HCWs were surveyed with a response rate of 70.6% over a median follow‐up period of 52 days. UK prevalence of OD and TD was 73.1% and 69.2%, respectively. There was a male to female ratio of 1:3 with 81.6% being white, 43.7% being nurses/health care assistants (HCAs), and 39.3% being doctors. In addition, 53.2% of them worked on COVID‐19 wards. Complete recovery was reported in 31.8% for OD and 47.1% for TD with a 52 days follow‐up. The job role of doctors and nurses negatively influenced smell (P = .04 and P = .02) and taste recovery (P = .02 and P = .01). Ethnicity (being white) showed to positively influence only taste recovery (P = .04). Sex (being female) negatively influenced OD and TD recovery only in Paduan HCWs (P = .02 and P = .011, respectively). Working on a COVID‐19 ward did not influence prognosis.

Conclusions

The prevalence of OD and TD was considerably higher in HCWs. The prognosis for OD and TD recovery was worse for nurses/HCAs and doctors but working on a COVID‐19 ward did not influence prognosis. Sixty‐eight percent of surveyed HCWs at 52 days continued to experience OD or TD requiring additional future medical management capacity.

Level of Evidence

4.
Enzyme Degradable Polymersomes from Chitosan‐g‐[poly‐l‐lysine‐block‐ε‐caprolactone] Copolymer
Authors: Bourgat Yannick , Tiersch Brigitte , Koetz Joachim , Menzel Henning
Published: December 2020

The scope of this study includes the synthesis of chitosan‐g‐[peptide‐poly‐ε‐caprolactone] and its self‐assembly into polymeric vesicles employing the solvent shift method. In this way, well‐defined core–shell structures suitable for encapsulation of drugs are generated. The hydrophobic polycaprolactone side‐chain and the hydrophilic chitosan backbone are linked via an enzyme‐cleavable peptide. The synthetic route involves the functionalization of chitosan with maleimide groups and the preparation of polycaprolactone with alkyne end‐groups. A peptide functionalized with a thiol group on one side and an azide group on the other side is prepared. Thiol‐ene click‐chemistry and azide–alkyne Huisgen cycloaddition are then used to link the chitosan and poly‐ε‐caprolactone chains, respectively, with this peptide. For a preliminary study, poly‐l‐lysin is a readily available and cleavable peptide that is introduced to investigate the feasibility of the system. The size and shape of the polymersomes are studied by dynamic light scattering and cryo‐scanning electron microscopy. Furthermore, degradability is studied by incubating the polymersomes with two enzymes, trypsin and chitosanase. A dispersion of polymersomes is used to coat titanium plates and to further test the stability against enzymatic degradation.
Controls and Effects of Monomer Junctions and Sequences in Curable and Degradable Polyarylate Containing Acrylate Moieties
Authors: Kohsaka Yasuhiro , Nagai Koki
Published: December 2020

In contrast to solution polymerization, interfacial polymerization of α‐(chloromethyl)acryloyl chloride and bisphenol Z results in fast esterification and slow ether formation, affording regulated monomer junctions. The controlled structure increases the crystallinity of the resulting polymers. In addition, terpolymerization with dicarboxylic acid chloride results in controlled monomer sequences with uniformly distributed acrylate moieties, leading to efficient curability.
The influence of contact engineering on silicon‐based anode for li‐ion batteries
Authors: Wu Pengfei , Chen Shaohong , Liu Anhua
Published: December 2020

Silicon is considered as the desirable anode material for lithium‐ion batteries due to its suitable discharge potential, abundant reserve, and ultra‐high specific capacity. However, poor conductivity and unstable battery performance caused by large volume change during cycling limit the further development of silicon anode. In order to avoid the unstable solid electrolyte interface layer caused by the direct contact between silicon and electrolyte, and to eliminate the structural collapse caused by the volume change during cycling, dimension size reduction, reserved voids, and novel structural framework are usually adopted. Although these methods can effectively improve the defects, a new problem is introduced and cannot be ignored: contact engineering between the coating layer and silicon core. Herein, contact engineering is classified into three categories: face to face (F2F), line to line (L2L), and point to point (P2P) according to the contact modes between the coating and core. There is utilizability of the structure categories of different contact modes and their influence on electrochemical performance. Therefore, in the future research of silicon anode, contact engineering is a non‐negligible aspect in the structural design process. Finally, feasible strategies based on contact engineering have been indicated.
Using Q‐methodology to understand stakeholder perspectives on a carnivore translocation
Authors: Bavin David , MacPherson Jenny , Denman Huw , Crowley Sarah L. , McDonald Robbie A.
Published: December 2020

Reversing global declines in predator populations is a major conservation objective, though people frequently come into conflict over carnivore conservation. As part of a national recovery programme for the pine martenMartes martes, a protected mesocarnivore in the UK, we used Q‐methodology to understand the perspectives of residents living in an area in which a pine marten translocation project was planned.

In contrast to binary ‘for or against’ characterizations of debates surrounding such projects, we identified four perspectives with distinct priorities and concerns. A single perspective, ‘Concerned Manager’, opposed the translocation and marten recovery more generally, was apprehensive about impacts and favoured traditional predator management practices. Support was characterized by three perspectives: ‘Environmental Protectionist’, ‘Natural Resource Steward’ and ‘Cautious Pragmatist’. Two explicitly supported the translocation but differed in their priorities: Environmental Protectionist framed marten restoration as an ethical imperative, whereas Natural Resource Steward emphasized ecological and economic benefits. Cautious Pragmatist supported marten recovery, but expressed ambivalence about the translocation.

We identified areas of divergence between the four perspectives, particularly surrounding risks posed by martens and need for predator control. We identified two areas of consensus among the four perspectives: support for a biodiverse environment and translocations as a means of achieving this (though this was contingent on the species), and agreement there would be economic and ecological benefits if martens controlled non‐native grey squirrelsSciurus carolinensis.

We highlight that perspectives on this project were influenced by wider issues of wildlife management and conservation, particularly the impact and management of increasing populations of another mesocarnivore, the badgerMeles meles. Negative experiences and perceptions of badgers were germane to the Concerned Manager perspective, and their fear that protected status would preclude marten population control. ‘Rewilding’ emerged as a divisive background issue, against which some participants evaluated the translocation.

In facilitating understanding of perspectives and establishing the contexts through which they were formed, we found that Q‐methodology enabled us, as a team comprising conservation practitioners and researchers, to engage meaningfully with affected residents. We recommend the tool as a useful step in assessing social feasibility of conservation translocations.

A freePlain Language Summarycan be found within the Supporting Information of this article.