bluuebunny/crossref_metadata_2025 huggingface dataset:
A Photoionization Study on the Detection of 1‐Sila Glycolaldehyde (HSiOCH2OH), 2‐Sila Acetic Acid (H3SiCOOH), and 1,2‐Disila Acetaldehyde (HSiOSiH3)
Authors: Chandra Sankhabrata , Eckhardt André K. , Turner Andrew M. , Tarczay György , Kaiser Ralf I.
Published: December 2020

The identification of silicon‐substituted, complex organics carrying multiple functional groups by classical infrared spectroscopy is challenging because the group frequencies of functional groups often overlap. Photoionization (PI) reflectron time‐of‐fight mass spectrometry (ReTOF‐MS) in combination with temperature‐programmed desorption (TPD) holds certain advantages because molecules are identified after sublimation from the matrix into in the gas phase based on distinct ionization energies and sublimation temperatures. In this study, we reveal the detection of 1‐silaglycolaldehyde (HSiOCH2OH), 2‐sila‐acetic acid (H3SiCOOH), and 1,2‐disila‐acetaldehyde (H3SiSiHO)—the silicon analogues of the well‐known glycolaldehyde (HCOCH2OH), acetic acid (H3CCOOH), and acetaldehyde (H3CCHO), in the gas phase after preparation in silane (SiH4)–carbon dioxide ices exposed to energetic electrons and subliming the neutral reaction products formed within the ices into the gas phase.
Comparison of Steroidogenic Exposure Following the Administration of Repository Corticotropin Injection With a Synthetic ACTH1‐24 Depot and Methylprednisolone in Healthy Subjects
Authors: Wang Xiaofeng , Pham Loan , Poola Nagaraju , Brooks Leah R. , Due Bryan
Published: December 2020

The pharmacokinetics (PK) and pharmacodynamics (PD) of clinically relevant doses of repository corticotropin injection (Acthar Gel) and synthetic ACTH1‐24 depot have not been fully characterized. We compared the steroidogenic exposure of repository corticotropin injection and synthetic ACTH1‐24 depot in healthy adults at therapeutic doses using data from 2 separate phase 1 studies. Subjects were randomly assigned to repository corticotropin injection 40 or 80 IU subcutaneously twice weekly or 80 IU subcutaneously 3 times weekly for 15 days or to daily synthetic ACTH1‐24 depot doses of 0.5 mg subcutaneously, 0.75 mg subcutaneously, 1 mg subcutaneously, or 1 mg intramuscularly for 5 days. A population PK/PD model was developed to simulate the free cortisol exposure of a clinically relevant dose of synthetic ACTH1‐24 depot (1 mg subcutaneously twice weekly). Study drug doses were converted to methylprednisolone‐equivalent doses using the steroidogenic exposure of methylprednisolone 16 mg daily as a conversion factor. Doses were also converted to prednisone equivalents using a coefficient of 1.25. These analyses revealed that the steroidogenic exposure of repository corticotropin injection at clinically relevant doses was substantially lower than that for synthetic ACTH1‐24 depot. The 3 repository corticotropin injection regimens were equivalent to approximately 5, 8, and 16 mg of daily prednisone, respectively. On the basis of simulated free cortisol exposure, synthetic ACTH1‐24 depot 1 mg subcutaneously twice weekly was comparable to 57 mg of daily prednisone. These results suggest that repository corticotropin injection has pharmacological effects that cannot be considered identical to synthetic ACTH1‐24 depot.
Anchoring Active Sites by Pt2FeNi Alloy Nanoparticles on NiFe Layered Double Hydroxides for Efficient Electrocatalytic Oxygen Evolution Reaction
Authors: Zheng Zhicheng , Guo Yanru , Wan Hao , Chen Gen , Zhang Ning , Ma Wei , Liu Xiaohe , Liang Shuquan , Ma Renzhi
Published: December 2020

Strategy of anchoring alloy nanoparticles made up of the efficient catalytic element (e.g., Ni, Fe) on dodecyl sulfate (DS‐)‐intercalated NiFe layered double hydroxides (DS‐‐NiFe LDH) obtained by a convenient one‐step hydrothermal coprecipitation method for essentially enhancing oxygen evolution reaction (OER) performance was proposed. The results of structural characterization indicate Pt2FeNi alloy nanoparticles evenly distribute on the surface of DS‐‐NiFe LDH. The sizes of the Pt2FeNi nanoparticles, closely related to their OER performance, could be well‐controlled by adjusting the amount of H2PtCl6 addition. The composite structure of as‐prepared product was stable during processes of synthesis, exfoliation, self‐assembly, and subsequent electrocatalytic OER. Rigorous electrochemical test proving the contributing catalytic active sites was located at the interface between Pt2FeNi and DS‐‐NiFe LDH, and the Ni and Fe were the major active elements while O atoms are adsorption sites. The formation of Pt2FeNi nanoparticles could greatly prompt the reduction of Tafel slope. The best‐performing Pt2FeNi/DS‐‐NiFe LDH with a Pt content of 0.98 wt% achieved low overpotential of 204 mV at 10 mA cm−2 and 262 mV at 50 mA cm−2. This work provides a convenient and effective strategy to create additional active sites for enhancing OER performance of NiFe LDH and make contribution to its wide application.
The prehospital patient pathway and experience of care with acute heart failure: a comparison of two health care systems
Authors: McCambridge Joseph , Keane Ciara , Walshe Myra , Campbell Patricia , Heyes James , Kalra Paul R. , Cowie Martin R. , Riley Jillian P. , O'Hanlon Rory , Ledwidge Mark , Gallagher Joseph , McDonald Kenneth
Published: December 2020

Aims

This study aimed to analyse community management of patients during the symptomatic period prior to admission with acute decompensated heart failure (ADHF).

Methods and results

We conducted a prospective, two‐centre, two‐country observational study evaluating care pathways and patient experience in patients admitted to hospital with ADHF. Quantitative and qualitative data were gathered from patients, carers, and general practitioners (GPs). From the Irish centre, 114 patients enrolled, and from the English centre, 50 patients. Symptom duration longer than 72 h prior to hospitalization was noted among 70.4% (76) Irish and 80% (40) English patients, with no significant difference between those with a new diagnosis of HF [de novo HF (dnHF)] and those with known HF [established HF (eHF)] in either cohort. For the majority, dyspnoea was the dominant symptom; however, 63.3% (31) of these Irish patients and 47.2% (17) of these English patients did not recognize this as an HF symptom, with no significant difference between dnHF and eHF patients. Of the 46.5% (53) of Irish and 38% (19) of English patients reviewed exclusively by GPs before hospitalization, numbers prescribed diuretics were low (11.3%, six; and 15.8%, three, respectively); eHF patients were no more likely to receive diuretics than dnHF patients. Barriers to care highlighted by GPs included inadequate access to basic diagnostics, specialist support and up‐to‐date patient information, and lack of GP comfort in managing HF.

Conclusion

The aforementioned findings, consistent across both health care jurisdictions, show a clear potential to intervene earlier and more effectively in ADHF or to prevent the need for hospitalization.
Chemistry for the Identification of Therapeutic Targets: Recent Advances and Future Directions
Authors: Khiar‐Fernández Nora , Macicior Jon , Marcos‐Ramiro Beatriz , Ortega‐Gutiérrez Silvia
Published: December 2020

The increasing availability of chemical probes for specific applications in chemical biology and medicinal chemistry is extensively facilitating our knowledge of biological systems. This understanding has fundamental implications in the development of new efficacious therapeutic strategies. Nowadays, successful drug discovery programs consider identification, engagement, and endogenous levels of the intended therapeutic target from the earliest preclinical stages. All these aspects are addressed with the use of chemical probes, compounds that rely on the use of a particular chemical reaction to give an answer to a specific biological question. In this review we will describe the underlying chemistry and the most recent advances experienced in the field together with their most important biomedical applications.
On a new block method for an MHD nanofluid flow with an exponentially decaying internal heat generation
Authors: Oyelakin Ibukun S. , Adeyeye Oluwaseun , Sibanda Precious , Omar Zurni
Published: December 2020

This study is an investigation of an exponentially decaying internal heat generation rate and free nanoparticle movement on the boundary layer. The equations describing the hydromagnetic flow and heat transfer in a viscous nanofluid moving over an isothermal stretching sheet are solved using a novel numerical approach. A comparison of flow and heat transfer characteristics between an actively controlled (AC) and a passively controlled (PC) nanoparticle concentration boundary is considered. The boundary value partial differential equations are transformed into a system of ordinary differential equations using similarity transformations. The system of ODEs is solved using a new block method without having to reduce the equivalent system to first‐order equations. The solutions are verified using the spectral local linearization method and further validation of the results is confirmed by comparing the current results, for some limiting cases, with those in existing literature. The solutions obtained using the block method are in good agreement with the solution obtained using the spectral local linearization method. The results are in good agreement with existing findings in previous studies. The solutions obtained using the AC and PC nanoparticle concentration boundary conditions are analyzed.
TiO2–Zr–Th–Y–rare‐earth elements ore deposit in unconsolidated fine‐grained sediments from Tongo Gandima in the Bétaré Oya Gold district, Eastern Cameroon
Authors: Ndjigui Paul‐Désiré , Bassanak Ongboye Paola Raissa , Ndong Bidzang François
Published: December 2020

Tongo Gandima is an area located in the southeastern part of the Bétaré Oya Gold district (Eastern Cameroon). Geochemical investigations on rare metals (TiO2, Th, Y, and rare‐earth elements [REE]) were carried out on sample types (source rocks, unconsolidated fine‐grained sediments, and concentrated sediments) using X‐ray diffraction (XRD), X‐ray fluorescence (XRF), inductively coupled plasma‐mass spectrometry (ICP‐MS), and scanning electron microscope equipped with EDAX spectrometer (SEM‐EDS) methods. In this study, five layers of river terraces were selected (organic matter layer, clayey layer, fine sandy layer, coarse sandy layer, and gravel layer). One of them, the gravel layer, is mineralized. TiO2, Zr, and REE are more enriched in monzonites than in granites. Unconsolidated sediments derive mainly from the erosion of weathered materials developed on monzonites and granites. The mineral assemblage of fine‐grained sediments from the gravel layer is muscovite, kaolinite, quartz, rutile, smectite, and others, and the average concentrations in Th, Zr, and Y are high. Fifty concentrated fractions from the same samples were analysed separately and their mineralogy is smectite, kaolinite, gibbsite, muscovite, quartz, rutile, anatase, zircon, titanomagnetite, and ilmenite. The heavy mineral fractions are opaque minerals, biotite, zircon, rutile, tourmaline, garnet, diopside, zoisite, and kyanite. TiO2, Zr, Th, Y, and REE contents are high. The REE oxides (REO) total grade ranges from 0.0088 to 15.66 wt%, marked by LREO‐abundance, especially in La2O3, Ce2O3, Pr2O3, and Nd2O3. The Tongo Gandima REO deposit was classified as LREO‐dominated type. The chondrite‐normalized REE patterns exhibit strong negative Eu anomalies; their V‐shaped patterns are typical of ore varieties. The abundant TiO2, Zr, Y, Th, and REE might have been influenced by surface processes (peneplanation and chemical weathering) and variations in sediment grain size. SEM‐EDS data reveal that apatite with Ce‐ and La‐dominant, monazite‐(Ce), and Ce‐Mn‐bearing ilmenite are rare metal‐bearing minerals. This study demonstrates that the economic importance of the alluvial‐fluvial placers from Tongo Gandima results from their high Ti, Zr, Th, Y, and REE contents.
Kif3a deletion prevents primary cilia assembly on oligodendrocyte progenitor cells, reduces oligodendrogenesis and impairs fine motor function
Authors: Cullen Carlie L. , O'Rourke Megan , Beasley Shannon J. , Auderset Loic , Zhen Yilan , Pepper Renee E. , Gasperini Robert , Young Kaylene M.
Published: December 2020

Primary cilia are small microtubule‐based organelles capable of transducing signals from growth factor receptors embedded in the cilia membrane. Developmentally, oligodendrocyte progenitor cells (OPCs) express genes associated with primary cilia assembly, disassembly, and signaling, however, the importance of primary cilia for adult myelination has not been explored. We show that OPCs are ciliated in vitro and in vivo, and that they disassemble their primary cilia as they progress through the cell cycle. OPC primary cilia are also disassembled as OPCs differentiate into oligodendrocytes. When kinesin family member 3a (Kif3a), a gene critical for primary cilium assembly, was conditionally deleted from adult OPCs in vivo (Pdgfrα‐CreER™:: Kif3a fl/fl transgenic mice), OPCs failed to assemble primary cilia. Kif3a‐deletion was also associated with reduced OPC proliferation and oligodendrogenesis in the corpus callosum and motor cortex and a progressive impairment of fine motor coordination.
Estimating (quality‐adjusted) life‐year losses associated with deaths: With application to COVID‐19
Authors: Briggs Andrew H. , Goldstein Daniel A. , Kirwin Erin , Meacock Rachel , Pandya Ankur , Vanness David J. , Wisløff Torbjørn
Published: December 2020

Many epidemiological models of the COVID‐19 pandemic have focused on preventing deaths. Questions have been raised as to the frailty of those succumbing to the COVID‐19 infection. In this paper we employ standard life table methods to illustrate how the potential quality‐adjusted life‐year (QALY) losses associated with COVID‐19 fatalities could be estimated, while adjusting for comorbidities in terms of impact on both mortality and quality of life. Contrary to some suggestions in the media, we find that even relatively elderly patients with high levels of comorbidity can still lose substantial life years and QALYs. The simplicity of the method facilitates straightforward international comparisons as the pandemic evolves. In particular, we compare five different countries and show that differences in the average QALY losses for each COVID‐19 fatality is driven mainly by differing age distributions for those dying of the disease.
Fatty Acid Desaturase 1 Influences Hepatic Lipid Homeostasis by Modulating the PPARα‐FGF21 Axis
Authors: Athinarayanan Shaminie , Fan Yang‐Yi , Wang Xiaokun , Callaway Evelyn , Cai Defeng , Chalasani Naga , Chapkin Robert S. , Liu Wanqing
Published: December 2020

The fatty acid desaturase 1 (FADS1), also known as delta‐5 desaturase (D5D), is one of the rate‐limiting enzymes involved in the desaturation and elongation cascade of polyunsaturated fatty acids (PUFAs) to generate long‐chain PUFAs (LC‐PUFAs). Reduced function of D5D and decreased hepatic FADS1 expression, as well as low levels of LC‐PUFAs, were associated with nonalcoholic fatty liver disease. However, the causal role of D5D in hepatic lipid homeostasis remains unclear. In this study, we hypothesized that down‐regulation of FADS1 increases susceptibility to hepatic lipid accumulation. We used in vitro and in vivo models to test this hypothesis and to delineate the molecular mechanisms mediating the effect of reduced FADS1 function. Our study demonstrated that FADS1 knockdown significantly reduced cellular levels of LC‐PUFAs and increased lipid accumulation and lipid droplet formation in HepG2 cells. The lipid accumulation was associated with significant alterations in multiple pathways involved in lipid homeostasis, especially fatty acid oxidation. These effects were demonstrated to be mediated by the reduced function of the peroxisome proliferator–activated receptor alpha (PPARα)–fibroblast growth factor 21 (FGF21) axis, which can be reversed by treatment with docosahexaenoic acid, PPARα agonist, or FGF21. In vivo, FADS1‐knockout mice fed with high‐fat diet developed increased hepatic steatosis as compared with their wild‐type littermates. Molecular analyses of the mouse liver tissue largely corroborated the observations in vitro, especially along with reduced protein expression of PPARα and FGF21. Conclusion: Collectively, these results suggest that dysregulation in FADS1 alters liver lipid homeostasis in the liver by down‐regulating the PPARα‐FGF21 signaling axis.
Breast cancer patient‐derived scaffolds as a tool to monitor chemotherapy responses in human tumor microenvironments
Authors: Leiva Maria Carmen , Garre Elena , Gustafsson Anna , Svanström Andreas , Bogestål Yalda , Håkansson Joakim , Ståhlberg Anders , Landberg Göran
Published: December 2020

Breast cancer is a heterogeneous disease where the tumor microenvironment, including extracellular components, plays a crucial role in tumor progression, potentially modulating treatment response. Different approaches have been used to develop three‐dimensional models able to recapitulate the complexity of the extracellular matrix. Here, we use cell‐free patient‐derived scaffolds (PDSs) generated from breast cancer samples that were recellularized with cancer cell lines as an in vivo‐like culture system for drug testing. We show that PDS cultured MCF7 cancer cells increased their resistance against the front‐line chemotherapy drugs 5‐fluorouracil, doxorubicin and paclitaxel in comparison to traditional two‐dimensional cell cultures. The gene expression of the environmentally adapted cancer cells was modulated in different ways depending on the drug and the concentration used. High doses of doxorubicin reduced cancer stem cell features, whereas 5‐fluorouracil increased stemness and decreased the proliferative phenotype. By using PDSs repopulated with other breast cancer cell lines, T‐47D and MDA‐MB‐231, we observed both general and cell line specific drug responses. In summary, PDSs can be used to examine the extracellular matrix influence on cancer drug responses and for testing novel compounds in in vivo‐like microenvironments.
Hair cell uptake of gentamicin in the developing mouse utricle
Authors: Qian Xiaoqing , He Ziyu , Wang Yanmei , Chen Binjun , Hetrick Alisa , Dai Chunfu , Chi Fanglu , Li Hongzhe , Ren Dongdong
Published: December 2020

Intratympanic injection of gentamicin has proven to be an effective therapy for intractable vestibular dysfunction. However, most studies to date have focused on the cochlea, so little is known about the distribution and uptake of gentamicin by the counterpart of the auditory system, specifically vestibular hair cells (HCs). Here, with a combination of in vivo and in vitro approaches, we used a gentamicin‐Texas Red (GTTR) conjugate to investigate the mechanisms of gentamicin vestibulotoxicity in the developing mammalian utricular HCs. In vivo, GTTR fluorescence was concentrated in the apical cytoplasm and the cellular membrane of neonatal utricular HCs, but scarce in the nucleus of HCs and supporting cells. Quantitative analysis showed the GTTR uptake by striolar HCs was significantly higher than that in the extrastriola. In addition, the GTTR fluorescence intensity in the striola was increased gradually from 1 to 8 days, peaking at 8–9 days postnatally. In vitro, utricle explants were incubated with GTTR and candidate uptake conduits, including mechanotransduction (MET) channels and endocytosis in the HC, were inhibited separately. GTTR uptake by HCs could be inhibited by quinine, a blocker of MET channels, under both normal and stressed conditions. Meanwhile, endocytic inhibition only reduced GTTR uptake in the CoCl2 hypoxia model. In sum, the maturation of MET channels mediated uptake of GTTR into vestibular HCs. Under stressed conditions, MET channels play a pronounced role, manifested by channel‐dependent stress enhanced GTTR permeation, while endocytosis participates in GTTR entry in a more selective manner.
LDL cholesterol promotes the proliferation of prostate and pancreatic cancer cells by activating the STAT3 pathway
Authors: Jung Young Yun , Ko Jeong‐Hyeon , Um Jae‐Young , Chinnathambi Arunachalam , Alharbi Sulaiman Ali , Sethi Gautam , Ahn Kwang Seok
Published: December 2020

Hypercholesterolemia has been found to be closely linked with a significant increase in both cancer incidence and mortality. However, the exact correlation between serum cholesterol levels and cancer has not been completely deciphered. Here we analyzed the effect of low‐density lipoprotein (LDL) cholesterol on prostate and pancreatic cancer cells. We noted that LDL induced a substantial STAT3 activation and JAK1, JAK2, Src activation in diverse prostate and pancreatic tumor cells. Moreover, LDL promoted cancer cell proliferation, migration, and invasion as well as upregulated the expression of diverse oncogenic gene products. However, deletion of LDL‐activated STAT3 in LNCaP and PANC‐1 cells and reduced LDL‐induced cell viability. Simvastatin (SV) treatment also alleviated LDL‐induced cell viability and migration ability in both the prostate and pancreatic tumor cells. These results demonstrate that LDL‐induced STAT3 activation may exert a profound effect on the proliferation and survival of tumor cells.
Obesity‐related genes are expressed in human Sertoli cells and modulated by energy homeostasis regulating hormones
Authors: Pereira Sara C. , Martins Ana C. , Moreira Bruno P. , Bernardino Raquel L. , Barros Alberto , Monteiro Mariana P. , Oliveira Pedro F. , Alves Marco G.
Published: December 2020

The strong hormonal dysregulation associated with obesity is responsible for the disruption of several reproductive events. Sertoli cells (SCs) function is dependent on energetic homeostasis and thus, directly associated with energy homeostasis regulating hormones. To further understand the influence of those hormones with SCs function and obesity, we hypothesize that human SCs express obesity‐related genes (ORG; MC4R, GNPDA2, TMEM18, and FTO) and that they respond to energy homeostasis regulating hormones (leptin, ghrelin, and glucagon‐like protein 1 [GLP‐1]) stimuli. To test our hypothesis, SCs were cultured with increasing doses of leptin (0, 5, 25, or 50 ng/ml, for 24 h), ghrelin (0, 20, 100, and 500 pM, for 24 h), and GLP‐1 (10, 1000, or 1 × 105 pM, for 6 h). The presence and abundance of ORG transcripts and proteins in SCs were accessed by polymerase chain reaction techniques, Western blot analysis, and immunofluorescence staining. Our results show that human SCs express MC4R, GNPDA2, TMEM18, and FTO in specific cellular locations. MC4R and FTO expression in human SCs was not responsive to the treatments. However, GNPDA2 and TMEM18 expression increased after exposure to the highest concentration of leptin and ghrelin, respectively. We highlight for the first time that human SCs express ORG and that these are responsive to energy homeostasis hormonal stimuli. GNPDA2 and TMEM18 expression respond in opposite directions according to overall energy status, mediated by energy homeostasis regulating hormones. Leptin and ghrelin control of ORG expression by human SCs can be associated with overweight‐related infertility and subfertility in males.
Regulatory environment for novel therapeutic development in mitochondrial diseases
Authors: Hirano Michio , Berardo Andres , Barca Emanuele , Emmanuele Valentina , Quinzii Catarina , Simpson Camilla V. , Engelstad Kristin , Rosales Xiomara Q. , Thompson John L. P.
Published: December 2020

At present, there is just one approved therapy for patients with mitochondrial diseases in Europe, another in Japan, and none in the United States. These facts reveal an important and significant unmet need for approved therapies for these debilitating and often fatal disorders. To fill this need, it is critical for clinicians and drug developers to work closely with regulatory agencies. In the United States, mitochondrial disease patients and clinicians, the United Mitochondrial Disease Foundation, and pharmaceutical industry members have engaged with the Food and Drug Administration to educate each other about these complex and heterogeneous diseases and about regulatory requirements to obtain approvals for novel therapies. Clinical development of therapies for rare diseases has been facilitated by the 1983 US Orphan Drug Act (ODA) and similar legislation in Japan and the European Union. Further legislation and regulatory guidance have expanded and refined regulatory flexibility. While regulatory and financial incentives of the ODA have augmented involvement of pharmaceutical companies, clinicians, with patient advocacy groups and industry, need to conduct natural history studies, develop clinical outcome measures, and identify potential supportive surrogate endpoints predictive of clinical benefit, which together are critical foundations for clinical trials. Thus, the regulatory environment for novel therapeutic development is conducive and offers flexibility for mitochondrial diseases. Nevertheless, flexibility does not mean lower standards, as well‐controlled rigorous clinical trials of high quality are still required to establish the efficacy of potential therapies and to obtain regulatory agency approvals for their commercial use. This process is illustrated through the authors' ongoing efforts to develop therapy for thymidine kinase 2 deficiency.
Seroprevalence of HBV and HCV in female sex workers from four cities in the state of Pará, northern Brazil
Authors: Miranda Nelba T. G. P. , de Souza Ronaldo L. , Monteiro Jacqueline C. , Costa Iran B. , Siravenha Leonardo Q. , da Luz Anderson L. B. , de Almeida Núbia C. C. , Oliveira‐Filho Aldemir B. , Laurentino Rogério V. , Machado Luiz F. A.
Published: December 2020

Female sex workers (FSWs) represent a high vulnerability group for the acquisition of sexual and parenteral infections such as hepatitis B virus (HBV) and hepatitis C virus (HCV) infections. The present study aimed to determine the prevalence of serological markers and risk factors associated with exposure to HBV and HCV among FSWs in the state of Pará, Brazil. A cross‐sectional study using principles of the time location sampling (TLS) method was conducted in four cities (Belém, Bragança, Barcarena, and Augusto Corrêa) of the state of Pará, from 2005 to 2006. In total, 365 FSWs were interviewed using a standardized questionnaire. Blood samples were collected and tested for serological markers of exposure to HBV and HCV using an enzyme immunoassay. The overall prevalence of exposure to HBV and HCV was 36.7% and 7.7%, respectively. The prevalence of surface antigen of HBV was 3.0%. The prevalence of anti‐HBc and anti‐HBc+ anti‐HBs antibodies were 6.3% and 27.4%. Very few (4.7%) FSWs had vaccine immunity against HBV (anti‐HBs antibodies only). The prevalence of anti‐HCV antibodies was 7.7%. Low monthly income, drug usage, and unprotected sex were some of the social characteristics associated with exposure to the viruses using different analysis. The seroprevalence of HBV and HCV infections among FSWs in four cities of the state of Pará is high when compared to the general population of Brazil, but similar to those found in FSWs in other nondeveloped countries. The prevalence of HBV was higher in Belém, while the prevalence of HCV was higher in the other three cities, highlighting the importance of establishing control and prevention programs to reduce the risk of acquiring these viruses in Pará.
Co‐infection of malaria and early clearance of SARS‐CoV‐2 in healthcare workers
Authors: Mahajan Niraj N. , Gajbhiye Rahul K. , Bahirat Shubhada , Lokhande Pradip D , Mathe Apeksha , Rathi Surbhi , Warty Neeta , Mahajan Kshitija N. , Srivastava Vartika , Kuppusamy Periyasamy , Mohite Shailesh C.
Published: December 2020

Healthcare workers (HCWs) are at higher risk of contracting severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection. Information regarding co‐infection of SARS‐CoV‐2 with vector‐borne diseases (malaria and dengue) is crucial especially for the countries wherein malaria and dengue are endemic. The objective was to study the prevalence, demographic, clinical presentations among HCWs with coronavirus disease 2019 (COVID‐19) and to compare the viral clearance in HCWs with COVID‐19 and co‐infection of malaria and dengue. This retrospective study was conducted at a dedicated COVID‐19 hospital, BYL Nair Charitable Hospital (NH), Mumbai, India April 6th–October 31st 2020. The SARS‐CoV‐2 infection in HCWs was confirmed by reverse transcription‐plymerase chain reaction. Out of 491 HCWs infected with SARS‐CoV‐2, analysis of viral clearance was carried out in 467 HCWs over seven month periods, The prevalence of SARS‐CoV‐2 infection in HCWs was 13% (491 out of 3711). Out of the HCWs with COVID‐19, prevalence of SARS‐CoV‐2 infection was higher among security guards (25%) with 1% mortality. The co‐infection of malaria or dengue was reported in 31 HCWs (6.3%). The mean duration of virus clearance was longer (12 days) in symptomatic HCWs as compared to asymptomatic (8 days, p < .005). The recovery of SARS‐CoV‐2 infection in HCWs was faster (mean 8 days) with co‐infection of malaria than without malaria (p < .005). We recommend universal testing of HCWs, to optimize staffing levels during the current pandemic as HCWs are the most precious resource. There is a need to effectively implement standard protocols for prevention of vector‐borne diseases, especially in the hospital settings.
Zeolitic imidazolate frameworks in analytical sample preparation
Authors: Rodas Melisa , Fikarová Kateřina , Pasanen Finnian , Horstkotte Burkhard , Maya Fernando
Published: December 2020

Zeolitic imidazolate frameworks are a class of metal–organic frameworks that are topologically isomorphic with zeolites. Zeolitic imidazolate frameworks are composed of tetrahedrally coordinated metal ions connected by imidazolate linkers and have a high porosity and chemical stability. Here, we summarize the progress made in the application of zeolitic imidazolate frameworks in sample preparation for analytical purposes. This review is focused on analytical methods based on liquid chromatography, gas chromatography, or capillary electrophoresis, where the use of zeolitic imidazolate frameworks has contributed to increasing the sensitivity and selectivity of the method. While bulk zeolitic imidazolate frameworks have been directly used in analytical sample preparation protocols, a variety of strategies for their magnetization or their incorporation into sorbent particles, monoliths, fibers, stir bars, or thin films, have been developed. These modifications have facilitated the handling and application of zeolitic imidazolate frameworks for a number of analytical sample treatments including magnetic solid‐phase extraction, solid‐phase microextraction, stir bar sorptive extraction, or thin film microextraction, among other techniques.
Impact of Pre‐operative Multidisciplinary Evaluation on Laryngotracheal Reconstruction Outcomes
Authors: Wertz Aileen , Ryan Matthew , Jacobs Ian , Piccione Joseph
Published: December 2020

Objective/Hypothesis

Determine if diagnostic findings from pre‐operative multidisciplinary evaluations are associated with single surgery or overall success rates in pediatric laryngotracheal reconstruction (LTR).

Study Design

Retrospective cohort.

Methods

Retrospective cohort study of patients undergoing LTR at a tertiary care children's hospital between January 01, 2008 and December 31, 2017. Success is defined as decannulation rate if tracheostomy present, and resolution of symptoms if tracheostomy not present. Cohorts compared were those who did and did not receive pulmonary and gastrointestinal preoperative testing. Multivariate, logistic regression, and Kaplan Meier analyses performed.

Results

About 165 children were included in the study. Median age was 3 years at the time of surgery; 73% of LTRs were double‐stage procedures. Single surgery and overall success rates were 75% and 87%, respectively. After adjusting for severity of stenosis and surgical approach, performing esophagogastroduodenoscopy (EGD) and normal gross appearance on EGD were associated with increased single surgery (P = .01, .005) and overall success (P = .005, .0003). Performing pH probe and normal EGD biopsy results was associated with increased overall success (P = .03, .007). Asthma and musculoskeletal comorbidities, postoperative complications, and need for postoperative balloon dilation were associated with decreased success. No other comorbidities evaluated impacted success.

Conclusions

Aerodigestive comorbidities are common in children undergoing LTR, and preoperative multidisciplinary workup often results in changes in management. After adjusting for grade and level of stenosis and staged approach, performing EGD and pH/impedance probe as well as normal gross and microscopic EGD findings was independently associated with increased LTR surgical success.

Level of Evidence

4 (retrospective cohort study) Laryngoscope, 131:E2356–E2362, 2021
Impact of air gap, range shifter, and delivery technique on skin dose in proton therapy
Authors: Kern A. , Bäumer C. , Kröninger K. , Wulff J. , Timmermann B.
Published: December 2020

Objective

Side effects of radiation therapy may include skin damage. The surface dose is of great interest and contains the buildup effect. In particular, the proton therapy community requires further experimental data to quantify doses in the surface region. This specification includes the skin dose, which is defined according to ICRU Report No. 39 at 70 μm water equivalent depth. The aim of this study is to gather more knowledge of the skin dose by varying key parameters defined by the patient treatment plan. This consists of clinical aspects such as the influence of the air gap, the application of a range shifter (RS), or the proton delivery technique.

Material/methods

Skin doses were determined with a PTW 23391 extrapolation chamber with three thin Kapton® entrance windows operated as a conventional ionization chamber. The impact on the skin dose for quasi‐monoenergetic pencil beam scanning (PBS) proton beams was evaluated for clinical air gaps between 3.5 and 51.1 cm. The differences in skin dose were assessed by irradiating equivalent fields with an RS of 51 mm water equivalent thickness (RS51) and without. Furthermore, the delivery techniques PBS, uniform scanning (US), and double scattering (DS) were compared by defining a spread‐out Bragg peak (SOBP). TOPAS (V.3.1.2) was used to model an IBA nozzle with PBS and to score dose to water at the surface of a water phantom.

Results

For the monoenergetic fields without the application of the RS the skin dose was constant down to an air gap of 6.2 cm. A lower air gap of 3.5 cm showed a variation in skin dose by up to 2.4% compared to the results obtained with larger air gaps. With the inserted RS51 an increase in the skin dose was found for air gaps smaller than 11.3 cm. Experimentally, a dose difference of 1.4% was recorded for an air gap of 6.2 cm by inserting an RS and none. With the Monte Carlo calculations the largest dose increase was observed at the air gap of 3.5 cm with 1.7% and 4.0% relative to the skin dose results without the RS and to the largest evaluated air gap of 51.1 cm, respectively. The SOBP comparison of the beam modalities at the measuring plane at the isocenter revealed higher skin doses without RS (including RS) by up to +1.9% (+1.5%) for DS and +1.3% (+1.1%) for US compared to PBS. For all three techniques an approx. 2% rise in skin dose was observed for the largest evaluated air gap of 37.7 cm to an air gap of 6.2 cm when using an RS51.

Conclusion

The study investigated aspects of skin dose of a water equivalent phantom by varying key parameters of a proton treatment plan. Parameters like the RS, the air gap, and the delivery modality have an impact on the order of 4.0% for the skin dose at the depth of 70 μm. The increases in skin dose are the effects of the contribution of the increased electron fluence at small air gaps and the emitted hadronic particles produced by the RS.
Trucks and drones cooperation in the last‐mile delivery process
Authors: Di Puglia Pugliese Luigi , Macrina Giusy , Guerriero Francesca
Published: December 2020

We address the problem of routing a fleet of trucks equipped with unmanned aerial vehicles, commonly known as drones, to perform deliveries in last‐mile delivery process. The customers can be served by either a truck or a drone within the respective time window of each. Each capacitated truck carries drones that can be launched to perform deliveries. The drone takes off from a truck located either at a customer or at the depot and it must land on the same truck after visiting a customer to be served. The aim is to serve all customers at minimum cost, under time window, capacity, and flying endurance constraints. We formulate the problem as a mixed integer linear program (MILP) and develop a heuristic procedure where a two‐phase strategy is embedded in a multi‐start framework. The computational results are carried out on instances generated by starting from vehicle routing problem with time windows benchmarks. We analyze the behavior of the considered transportation system by mean of the solutions provided by the MILP. The proposed formulation is able to solve instances with up to 15 customers. The solutions of the MILP are used as benchmark to assess the effectiveness of the proposed heuristic procedure.
Microscale Photopatterning of Through‐Thickness Modulus in a Monolithic and Functionally Graded 3D‐Printed Part
Authors: Uzcategui Asais Camila , Higgins Callie I. , Hergert John E. , Tomaschke Andrew E. , Crespo-Cuevas Victor , Ferguson Virginia L. , Bryant Stephanie J. , McLeod Robert R. , Killgore Jason P.
Published: December 2020

3D printing is transforming traditional processing methods for applications ranging from tissue engineering to optics. To fulfill its maximum potential, 3D printing requires a robust technique for producing structures with precise 3D (x, y, and z) control of mechanical properties. Previous efforts to realize such spatial control of modulus within 3D‐printed parts have largely focused on low‐resolution (from mm to cm scale) multimaterial processes and grayscale approaches that spatially vary the modulus in the x–y plane and energy dose‐based (E = I0 texp) models that do not account for the resin's sublinear response to irradiation intensity. Here, a novel approach for through‐thickness (z) voxelated control of mechanical properties within a single‐material, monolithic part is demonstrated. Control over the local modulus is enabled by a predictive model that incorporates the material's nonreciprocal dose response. The model is validated by application of atomic force microscopy to map the through‐thickness modulus on multilayered 3D parts. Overall, both smooth gradations (30 MPa change over ≈75 μm) and sharp step changes (30 MPa change over ≈5 μm) in the modulus are realized in poly(ethylene glycol) diacrylate‐based 3D constructs, paving the way for advancements in tissue engineering, stimuli–responsive 4D printing, and graded metamaterials.
Impact of Cultivar and Growing Conditions on Alpha‐Amylase Properties in Wheat
Authors: Aljabi Hanadi Riyad , Pawelzik Elke
Published: December 2020

Alpha amylase (α‐amylase) is an endo‐amylolytic enzyme that plays an important role in the starch metabolism in developing wheat grains. However, excessive enzyme activity in post‐harvest wheat grains has adverse effects on grain quality. Therefore, the objective of the study is to determine the influence of cultivars with different growth habits (spring vs winter) and weather conditions on the characterization of native α‐amylase. The results show that winter wheat cultivar (cv.) Cubus show a lower α‐amylase activity than those of spring wheat cv. Amaretto, by escaping the humid weather before harvest. Grains exposed to higher temperatures in Gladebeck have lower enzyme activity in the later stages of ripening than the grains in Torland. On the other hand, wheat α‐amylases from both cultivars have similar properties. They show thermal inactivation at 30 °C and acid lability at increasing pH values. The results indicate that a better understanding of the α‐amylase properties could be helpful to develop a suitable management to avoid quality losses in wheat.
ZeeLung technology shows its ability to quickly, easily and cost-effectively upgrade existing WWTPs
Authors: Atkinson Simon
Published: December 2020

Technology from SUEZ that maximises treatment capacity in existing tank volumes at wastewater treatment plants (WWTPs) – whilst also reducing energy consumption – is being used to upgrade a facility in Ontario, Canada. This focus article provides an insight into what is involved and the benefits gained.
Cold‐Season Arctic Amplification Driven by Arctic Ocean‐Mediated Seasonal Energy Transfer
Authors: Chung Eui‐Seok , Ha Kyung‐Ja , Timmermann Axel , Stuecker Malte F. , Bodai Tamas , Lee Sang‐Ki
Published: December 2020

The Arctic warming response to greenhouse gas forcing is substantially greater than the rest of the globe. It has been suggested that this phenomenon, commonly referred to as Arctic amplification, and its peak in boreal fall and winter result primarily from the lapse‐rate feedback, which is associated with the vertical structure of tropospheric warming, rather than from the sea‐ice albedo feedback, which operates mainly in summer. However, future climate model projections show consistently that an overall reduction of sea‐ice in the Arctic region leads to a gradual weakening of Arctic amplification, thereby implying a key role for sea‐ice albedo feedback. To resolve this apparent contradiction, we conduct a comprehensive analysis using atmosphere/ocean reanalysis data sets and a variety of climate model simulations. We show that the Arctic Ocean acts as a heat capacitor, storing anomalous heat resulting from the sea‐ice loss during summer, which then gets released back into the atmosphere during fall and winter. Strong air‐sea heat fluxes in fall/winter in sea‐ice retreat regions in conjunction with a stably stratified lower troposphere lead to a surface‐intensified warming/moistening, augmenting longwave feedback processes to further enhance the warming. The cold‐season surface‐intensified warming/moistening is found to virtually disappear if ocean‐atmosphere‐sea ice interactions are suppressed, demonstrating the importance of ice insulation effect and ocean heat uptake/release. These results strongly suggest that the warm‐season ocean heat recharge and cold‐season heat discharge link and integrate the warm and cold season feedbacks, and thereby effectively explain the predominance of the Arctic amplification in fall and winter.
Explosive Submarine Eruptions: The Role of Condensable Gas Jets in Underwater Eruptions
Authors: Cahalan R. C. , Dufek J.
Published: December 2020

In explosive submarine eruptions, volcanic jets transport fragmented tephra and exsolved gases from the conduit into the water column. Upon eruption the volcanic jet mixes with seawater and rapidly cools. This mixing and associated heat transfer ultimately determines whether steam present in the jet will completely condense or rise to breach the sea surface and become a subaerial hazard. We develop a multiphase model with subgrid calculations for in situ steam condensation to explore the relationship between eruption conditions (e.g., water depth, mass eruption rate, and eruption temperature) and the produced steam jet height and breach potential. We find that mass eruption rate is the predominant control of jet height, more so than vent width. We present a series of parameter maps predicting the limits of eruption breach for water depths of 200, 500, and 1,000 m. We demonstrate the relationship between subsurface jets and sea surface temperature anomalies, and sea surface displacement. Lastly, we evaluate the role of dispersed ash on volcanic jet development by comparing jets with particles of different size and density, as well as differing eruption conditions with particles.
Dynamic event‐based dissipative asynchronous control for singular Markov jump LPV systems with general transition rates
Authors: Xing Ming Qi , Wang Yan Qian , Zhuang Guang Ming , Chen Fu
Published: December 2020

In this article, the dissipative asynchronous control is investigated for a series of continuous‐time singular Markov jump linear parameter‐varying (SMJLPV) systems under a dynamic event‐triggered scheme, in which the system parameters depend on the measured parameters in real time. The dynamic event‐triggered scheme (DES) is used to bring down the channel congestion caused by the limited bandwidth and raise the utilisation ratio of network resources. Then, the Markov chains of SMJLPV systems with partially known transition rates are discussed, which can further reduce the conservatism to some extent. Specifically, since the controller cannot accurately receive the modes information of the system in real time, the hidden Markov model is established to depict the asynchronous phenomenon. Next, in the light of the parameter‐dependence Lyapunov functional, the criteria of stochastically admissible for the considered SMJLPV systems with the given dissipative performance is obtained. In such context, parameter‐dependent linear matrix inequalities are obtained and a cooperative design method of asynchronous controller and the weighting matrix of the DES is proposed. Finally, numerical examples under two different event‐triggered schemes are given to verify the effectiveness of the proposed method.
On robust stability of switched homogeneous systems
Authors: Yang Hao , Zhao Dong , Jiang Bin , Ding Shihong
Published: December 2020

This paper analyses the robust stability of a class of homogeneous systems where a relation among the high‐order term, the decay rate and the domain of attraction of the system is explicitly established. Such a new observation helps to establish several robust stability conditions for switched homogeneous systems with high‐order terms. Several domains of attraction related to asymptotical and finite‐time stability properties are also provided. The new results are further applied to supervisory control of spacecraft attitude system with high‐order uncertainties to illustrate their efficiency and applicability.
Proactive repair crew deployment to improve transmission system resilience against hurricanes
Authors: Bian Yiheng , Bie Zhaohong , Li Gengfeng
Published: December 2020

Extreme weather events, such as hurricanes, impose severe impacts on power systems. A rapid repair for power systems is desired after hurricanes pass to mitigate load‐shedding losses. This study proposes a proactive repair crew deployment model to prepare for post‐disaster repair and restoration. A two‐stage stochastic optimisation framework is designed. In the first stage, the repair crews are allocated to candidate locations ahead of a hurricane. In the second stage, the repair dispatch and load restoration are implemented under several damage scenarios to support the first‐stage decision‐making. A novel repair crew routing method is proposed which considers repair crew cooperation on important damaged components to enable earlier restoration of critical load. A linear‐programming approximation of AC power flow is applied to model the restoration of the transmission system in which the generator start‐up characters and security constraints are incorporated. A scenario‐based decomposition algorithm is applied to solve the stochastic problem and a preprocessing method to identify necessary components is proposed to further reduce computation time. Case studies validate the effectiveness of the proposed model in improving transmission system resilience.