bluuebunny/crossref_metadata_2025 huggingface dataset:
Quasi-distributed acoustic sensing with interleaved identical chirped pulses for multiplying the measurement slew-rate
Authors: Wang Zitan , Jiang Jialin , Wang Zinan , Xiong Ji , Qiu Zijie , Liu Chunye , Rao Yunjiang
Published: November 2020

Quasi-distributed acoustic sensing (Q-DAS) based on ultra-weak fiber Bragg grating (UWFBG) is currently attracting great attention, due to its high sensitivity and excellent multiplexing capability. Phase-sensitive optical time-domain reflectometry (Φ-OTDR) based on phase demodulation is one of the most promising interrogation schemes for Q-DAS. In this article, a novel interleaved identical chirped pulse (IICP) approach is proposed on the basis of pulse compression Φ-OTDR with coherent detection. Different from the frequency-division-multiplexing (FDM) method, the identical pulses are used for multiplexing in the IICP scheme, and the mixed reflection signals can be demodulated directly, so the inconsistent phase offsets in FDM can be avoided. As a result, this scheme can enlarge the measurement slew-rate (SR) of Q-DAS by times compared with traditional single pulse scheme. In the proof-of-principle experiment, the SR of 28.9 mɛ/s has been achieved with an 860 m sensing range, which is 5 times as that of the traditional single pulse scheme; meanwhile, the response bandwidth has been enlarged by 5 times. The 277 kHz response bandwidth has been achieved, with 5 m spatial resolution and 2.8

p
ε

/

Hz

strain sensitivity.
Far-field controllable excitation of phonon polariton via nanostructure engineering
Authors: Qiang Bo , Yuan Guanghui , Zhao Meng , Liu Hong , Wang Qi Jie , Wang Qian
Published: November 2020

Hexagonal boron nitride (h-BN) as a natural mid-infrared (mid-IR) hyperbolic material which supports a strong excitation of phonon polariton (PhP) has enabled a new class of photonic devices with unprecedented functionalities. The hyperbolic property of h-BN has not only brought in new physical insights but also spurred potential applications. However, most of the current h-BN devices are designed repying on near-field excitation and manipulation of PhP. For fully realizing the potentials of h-BN, research on far-field controllable excitation and control of PhP is important for future integrated photonic devices. In this work, we exploit the designs of controllable far-field excitation of PhP in nanostructure-patterned h-BN thin film for deep subwavelength focusing (FWHM∼λ0/14.9) and interference patterns of 1D (FWHM∼λ0/52) and 2D standing waves (FWHM∼λ0/36.8) which find great potential for super-resolution imaging beyond diffraction limit. These polaritonic patterns could be easily tuned remotely by manipulating the polarization and phase of incident laser. This approach provides a novel platform for practical IR nanophotonic devices and potential applications in mid-IR bio-imaging and sensing.
3D nanoprinted kinoform spiral zone plates on fiber facets for high-efficiency focused vortex beam generation
Authors: Yu Jian , Bai Zhiyong , Zhu Guoxuan , Fu Cailing , Li Yali , Liu Shen , Liao Changrui , Wang Yiping
Published: November 2020

In this paper, we propose and demonstrate an all-fiber high-efficiency focused vortex beam generator. The generator is fabricated by integrating a kinoform spiral zone plate (KSZP) on the top of the composite fiber structure using fs-laser two-photon polymerization 3D nanoprinting. The KSZP with spiral continuous-surface relief feature is designed by superimposing a spiral phase into a kinoform lens, which can efficiently concentrate and transform an all incident beam to a single-focus vortex beam, without the undesired zero-order diffracted light and extra high-order focus. Under arbitrary polarized light incident conditions, experiment results show that the focusing efficiency and vortex purity of the all-fiber generators are over 60% and 86%, respectively, which is much higher than that of a traditional binary SZP integrated on an optical fiber facet. In addition, characteristics of the generated vortex beam, such as focal spot, focal length and vortex topological charge are numerically designed and experimentally investigated. The experimental results agree well with the numerical simulation model using the FDTD algorithm. Due to the compact size, flexible design, polarization insensitivity, high focusing efficiency and high vortex purity, the proposed all-fiber photonic devices have promising potential in optical communication, particle manipulation and quantum computation applications.
Measurement of the Kerr nonlinear refractive index of the Rb vapor based on an optical frequency comb using the z-scan method
Authors: Wang Sandan , Yuan Jinpeng , Wang Lirong , Xiao Liantuan , Jia Suotang
Published: November 2020

We report the measurement of the Kerr nonlinear refractive index of the rubidium vapor via the high sensitivity z-scan method by using an optical frequency comb. The novel self-focusing and self-defocusing effects of the vapor are presented with red and blue detunings of the laser frequency. The optical nonlinear characteristics of the rubidium vapor are clearly interpreted under different experimental parameters. Furthermore, the Kerr nonlinear refractive index n2 is obtained from the measured dispersion curve, and it basically occurs on the order of 10−6 cm2/W. The evolutions of the Kerr nonlinear coefficient n2 with the laser power and frequency detuning, respectively, are studied. To the best of our knowledge, the use of pulsed lasers to measure the Kerr nonlinear refractive index n2 of atomic vapor has not been reported yet. The direct measurement of the Kerr nonlinear coefficient will greatly help us understand and optimize nonlinear optical processes and find its more potential applications in quantum optics.
Pump-shaping of non-collinear and non-degenerate entangled photons
Authors: Lib Ohad , Bromberg Yaron
Published: November 2020

Free-space quantum key distribution is gaining increasing interest as a leading platform for long range quantum communication. However, the sensitivity of quantum correlations to scattering induced by turbulent atmospheric links limits the performance of such systems. Recently, a method for compensating for the scattering of entangled photons was demonstrated, allowing for real-time optimization of their quantum correlations. In this Letter, we demonstrate the use of wavefront shaping for compensating for the scattering of non-collinear and non-degenerate entangled photons. These results demonstrate the applicability of wavefront shaping schemes for protocols utilizing the large bandwidth and emission angle of the entangled photons.
Observation of second-order interference beyond the coherence time with true thermal photons
Authors: Lee Gyu-Hyeok , Im Dong-Gil , Kim Yosep , Kim U-Shin , Kim Yoon-Ho
Published: November 2020

It has recently been shown that counter-intuitive Franson-like second-order interference can be observed with a pair of classically correlated pseudo thermal light beams and two separate unbalanced interferometers (UIs): the second-order interference visibility remains fixed at 1/3 even though the path length difference in each UI is increased significantly beyond the coherence length of the pseudo thermal light [Phys. Rev. Lett. 119, 223603 (2017)PRLTAO0031-900710.1103/PhysRevLett.119.223603]. However, as the pseudo thermal beam itself originated from a long-coherence laser (and by using a rotating ground disk), there exists the possibility of a classical theoretical model to account for second-order interference beyond the coherence time on the long coherence time of the original laser beam. In this work, we experimentally explore this counter-intuitive phenomenon with a true thermal photon source generated via quantum thermalization, i.e., obtaining a mixed state from a pure two-photon entangled state. This experiment not only demonstrates the unique second-order coherence properties of thermal light clearly but may also open up remote sensing applications based on such effects.
Deep plug-and-play priors for spectral snapshot compressive imaging
Authors: Zheng Siming , Liu Yang , Meng Ziyi , Qiao Mu , Tong Zhishen , Yang Xiaoyu , Han Shensheng , Yuan Xin
Published: November 2020

We propose a plug-and-play (PnP) method that uses deep-learning-based denoisers as regularization priors for spectral snapshot compressive imaging (SCI). Our method is efficient in terms of reconstruction quality and speed trade-off, and flexible enough to be ready to use for different compressive coding mechanisms. We demonstrate the efficiency and flexibility in both simulations and five different spectral SCI systems and show that the proposed deep PnP prior could achieve state-of-the-art results with a simple plug-in based on the optimization framework. This paves the way for capturing and recovering multi- or hyperspectral information in one snapshot, which might inspire intriguing applications in remote sensing, biomedical science, and material science. Our code is available at: https://github.com/zsm1211/PnP-CASSI.
Integrative analysis of structural variations using short-reads and linked-reads yields highly specific and sensitive predictions
Authors: Sethi Riccha , Becker Julia , Graaf Jos de , Löwer Martin , Suchan Martin , Sahin Ugur , Weber David
Published: November 2020

Genetic diseases are driven by aberrations of the human genome. Identification of such aberrations including structural variations (SVs) is key to our understanding. Conventional short-reads whole genome sequencing (cWGS) can identify SVs to base-pair resolution, but utilizes only short-range information and suffers from high false discovery rate (FDR). Linked-reads sequencing (10XWGS) utilizes long-range information by linkage of short-reads originating from the same large DNA molecule. This can mitigate alignment-based artefacts especially in repetitive regions and should enable better prediction of SVs. However, an unbiased evaluation of this technology is not available. In this study, we performed a comprehensive analysis of different types and sizes of SVs predicted by both the technologies and validated with an independent PCR based approach. The SVs commonly identified by both the technologies were highly specific, while validation rate dropped for uncommon events. A particularly high FDR was observed for SVs only found by 10XWGS. To improve FDR and sensitivity, statistical models for both the technologies were trained. Using our approach, we characterized SVs from the MCF7 cell line and a primary breast cancer tumor with high precision. This approach improves SV prediction and can therefore help in understanding the underlying genetics in various diseases.
Within-host mechanisms of immune regulation explain the contrasting dynamics of two helminth species in both single and dual infections
Authors: Vanalli Chiara , Mari Lorenzo , Righetto Lorenzo , Casagrandi Renato , Gatto Marino , Cattadori Isabella M.
Published: November 2020

Variation in the intensity and duration of infections is often driven by variation in the network and strength of host immune responses. While many of the immune mechanisms and components are known for parasitic helminths, how these relationships change from single to multiple infections and impact helminth dynamics remains largely unclear. Here, we used laboratory data from a rabbit-helminth system and developed a within-host model of infection to investigate different scenarios of immune regulation in rabbits infected with one or two helminth species. Model selection suggests that the immunological pathways activated against Trichostrongylus retortaeformis and Graphidium strigosum are similar. However, differences in the strength of these immune signals lead to the contrasting dynamics of infections, where the first parasite is rapidly cleared and the latter persists with high intensities. In addition to the reactions identified in single infections, rabbits with both helminths also activate new pathways that asymmetrically affect the dynamics of the two species. These new signals alter the intensities but not the general trend of the infections. The type of interactions described can be expected in many other host-helminth systems. Our immune framework is flexible enough to capture different mechanisms and their complexity, and provides essential insights to the understanding of multi-helminth infections.
Evaluation of the cell culture based and the mouse brain derived inactivated vaccines against Crimean-Congo hemorrhagic fever virus in transiently immune-suppressed (IS) mouse model
Authors: Pavel Shaikh Terkis Islam , Yetiskin Hazel , Kalkan Ahmet , Ozdarendeli Aykut
Published: November 2020

Crimean-Congo hemorrhagic fever virus (CCHFV) is a tick-borne virus in the Nairoviridae family within the Bunyavirales order of viruses. Crimean-Congo hemorrhagic fever (CCHF) is the most widespread among tick-borne human viral diseases. It is endemic in many areas of Africa, Asia, the Middle East, in the Balkans, Russia and countries of the former Soviet Union. The confirmed CCHF cases were seen in Spain in 2016 to signify expansion of the virus into new geographical areas. CCHFV causes a viral human disease characterized by sudden onset of fever, headache, abdominal pain, nausea, hypotension, hemorrhage, and hepatic dysfunction with fatality rates up to 30%. Currently, there are no spesific treatments or licensed vaccines available for CCHFV. The absence of a susceptible animal model for CCHFV infection was severely hindered work on the development of vaccines. However, several animal models of CCHFV infection have been recently developed and used to assess vaccine efficacy. In this study, we have used the transiently immune-suppressed (IS) mouse model that MAb-5A3 was used to block IFN-I signaling in immune intact, wild-type mice at the time of CCHFV infection to evaluate the immune response and efficacy of the cell culture based and the mouse brain derived inactivated vaccines against CCHFV. Both vaccine preparations have provided complete protection but the cell culture based vaccine more effectively induced to CCFHV spesific antibodies and T cell responses. This is the first comparison of the cell culture based and the mouse brain derived vaccines for assessing the protective efficacy and the immunogenicity in the IS mouse CCHFV model.
Testing IgG antibodies against the RBD of SARS-CoV-2 is sufficient and necessary for COVID-19 diagnosis
Authors: Indenbaum Victoria , Koren Ravit , Katz-Likvornik Shiri , Yitzchaki Mayan , Halpern Osnat , Regev-Yochay Gili , Cohen Carmit , Biber Asaf , Feferman Tali , Cohen Saban Noy , Dhan Roni , Levin Tal , Gozlan Yael , Weil Merav , Mor Orna , Mandelboim Michal , Sofer Danit , Mendelson Ella , Lustig Yaniv
Published: November 2020

The COVID-19 pandemic and the fast global spread of the disease resulted in unprecedented decline in world trade and travel. A critical priority is, therefore, to quickly develop serological diagnostic capacity and identify individuals with past exposure to SARS-CoV-2. In this study serum samples obtained from 309 persons infected by SARS-CoV-2 and 324 of healthy, uninfected individuals as well as serum from 7 COVID-19 patients with 4–7 samples each ranging between 1–92 days post first positive PCR were tested by an “in house” ELISA which detects IgM, IgA and IgG antibodies against the receptor binding domain (RBD) of SARS-CoV-2. Sensitivity of 47%, 80% and 88% and specificity of 100%, 98% and 98% in detection of IgM, IgA and IgG antibodies, respectively, were observed. IgG antibody levels against the RBD were demonstrated to be up regulated between 1–7 days after COVID-19 detection, earlier than both IgM and IgA antibodies. Study of the antibody kinetics of seven COVID 19 patients revealed that while IgG levels are high and maintained for at least 3 months, IgM and IgA levels decline after a 35–50 days following infection. Altogether, these results highlight the usefulness of the RBD based ELISA, which is both easy and cheap to prepare, to identify COVID-19 patients even at the acute phase. Most importantly our results demonstrate that measuring IgG levels alone is both sufficient and necessary to diagnose past exposure to SARS-CoV-2.
Social Enterprise Model (SEM) for private sector tuberculosis screening and care in Bangladesh
Authors: Banu Sayera , Haque Farhana , Ahmed Shahriar , Sultana Sonia , Rahman Md. Mahfuzur , Khatun Razia , Paul Kishor Kumar , Kabir Senjuti , Rahman S. M. Mazidur , Banu Rupali Sisir , Islam Md. Shamiul , Ross Allen G. , Clemens John D. , Stevens Robert , Creswell Jacob
Published: November 2020

Background

In Bangladesh, about 80% of healthcare is provided by the private sector. Although free diagnosis and care is offered in the public sector, only half of the estimated number of people with tuberculosis are diagnosed, treated, and notified to the national program. Private sector engagement strategies often have been small scale and time limited. We evaluated a Social Enterprise Model combining external funding and income generation at three tuberculosis screening centres across the Dhaka Metropolitan Area for diagnosing and treating tuberculosis.

Methods and findings

The model established three tuberculosis screening centres across Dhaka Metropolitan Area that carried the icddr,b brand and offered free Xpert MTB/RIF tests to patients visiting the screening centres for subsidized, digital chest radiographs from April 2014 to December 2017. A network of private and public health care providers, and community recommendation was formed for patient referral. No financial incentives were offered to physicians for referrals. Revenues from radiography were used to support screening centres’ operation. Tuberculosis patients could choose to receive treatment from the private or public sector. Between 2014 and 2017, 1,032 private facilities networked with 8,466 private providers were mapped within the Dhaka Metropolitan Area. 64, 031 patients with TB symptoms were referred by the private providers, public sector and community residents to the three screening centres with 80% coming from private providers. 4,270 private providers made at least one referral. Overall, 10,288 pulmonary and extra-pulmonary tuberculosis cases were detected and 7,695 were bacteriologically positive by Xpert, corresponding to 28% of the total notifications in Dhaka Metropolitan Area.

Conclusion

The model established a network of private providers who referred individuals with presumptive tuberculosis without financial incentives to icddr,b’s screening centres, facilitating a quarter of total tuberculosis notifications in Dhaka Metropolitan Area. Scaling up this approach may enhance national and international tuberculosis response.
MAGE-A3 is a prognostic biomarker for poor clinical outcome in cutaneous squamous cell carcinoma with perineural invasion via modulation of cell proliferation
Authors: Chen Aaron , Santana Alexis L. , Doudican Nicole , Roudiani Nazanin , Laursen Kristian , Therrien Jean-Philippe , Lee James , Felsen Diane , Carucci John A.
Published: November 2020

Perineural invasion is a pathologic process of neoplastic dissemination along and invading into the nerves. Perineural invasion is associated with aggressive disease and a greater likelihood of poor outcomes. In this study, 3 of 9 patients with cutaneous squamous cell carcinoma and perineural invasion exhibited poor clinical outcomes. Tumors from these patients expressed high levels of MAGE-A3, a cancer testis antigen that may contribute to key processes of tumor development. In addition to perineural invasion, the tumors exhibited poor differentiation and deep invasion and were subsequently classified as Brigham and Women’s Hospital tumor stage 3. Cyclin E, A and B mRNA levels were increased in these tumors compared with normal skin tissues (102.93±15.03 vs. 27.15±4.59, 36.83±19.41 vs. 11.59±5.83, 343.77±86.49 vs. 95.65±29.25, respectively; p<0.05). A431 cutaneous squamous cell carcinoma cells pretreated with MAGE-A3 antibody exhibited a decreased percentage S-phase cells (14.13±2.8% vs. 33.97±1.1%; p<0.05) and reduced closure in scratch assays (43.88±5.49% vs. 61.17±3.97%; p = 0.0058). In a syngeneic animal model of squamous cell carcinoma, immunoblots revealed overexpression of MAGE-A3 and cyclin E, A, and B protein in tumors at 6 weeks. However, knockout of MAGE-A3 expression caused a reduction in tumor growth (mean tumor volume 155.3 mm3 vs. 3.2 mm3) compared with parental cells. These results suggest that MAGE-A3 is a key mediator in cancer progression. Moreover, elevated collagen XI and matrix metalloproteases 3, 10, 11, and 13 mRNA levels were observed in poorly differentiated cutaneous squamous cell carcinoma with perineural invasion compared with normal skin tissue (1132.56±882.7 vs. 107.62±183.62, 1118.15±1109.49 vs. 9.5±5, 2603.87±2385.26 vs. 5.29±3, 957.95±627.14 vs. 400.42±967.66, 1149.13±832.18 vs. 19.41±35.62, respectively; p<0.05). In summary, this study highlights the potential prognostic value of MAGE-A3 in clinical outcomes of cutaneous squamous cell carcinoma patients.
Community partners’ responses to items assessing stakeholder engagement: Cognitive response testing in measure development
Authors: Thompson Vetta L. Sanders , Leahy Nora , Ackermann Nicole , Bowen Deborah J. , Goodman Melody S.
Published: November 2020

Background

Despite recognition of the importance of stakeholder input into research, there is a lack of validated measures to assess how well constituencies are engaged and their input integrated into research design. Measurement theory suggests that a community engagement measure should use clear and simple language and capture important components of underlying constructs, resulting in a valid measure that is accessible to a broad audience.

Objective

The primary objective of this study was to evaluate how community members understood and responded to a measure of community engagement developed to be reliable, valid, easily administered, and broadly usable.

Method

Cognitive response interviews were completed, during which participants described their reactions to items and how they processed them. Participants were asked to interpret item meaning, paraphrase items, and identify difficult or problematic terms and phrases, as well as provide any concerns with response options while responding to 16 of 32 survey items.

Results

The results of the cognitive response interviews of participants (N = 16) suggest concerns about plain language and literacy, clarity of question focus, and the lack of context clues to facilitate processing in response to items querying research experience. Minimal concerns were related to response options. Participants suggested changes in words and terms, as well as item structure.

Conclusion

Qualitative research can improve the validity and accessibility of measures that assess stakeholder experience of community-engaged research. The findings suggest wording and sentence structure changes that improve ability to assess implementation of community engagement and its impact on research outcomes.
Increased signal diversity/complexity of spontaneous EEG, but not evoked EEG responses, in ketamine-induced psychedelic state in humans
Authors: Farnes Nadine , Juel Bjørn E. , Nilsen André S. , Romundstad Luis G. , Storm Johan F.
Published: November 2020

How and to what extent electrical brain activity reflects pharmacologically altered states and contents of consciousness, is not well understood. Therefore, we investigated whether measures of evoked and spontaneous electroencephalographic (EEG) signal diversity are altered by sub-anaesthetic levels of ketamine compared to normal wakefulness, and how these measures relate to subjective experience. High-density 62-channel EEG was used to record spontaneous brain activity and responses evoked by transcranial magnetic stimulation (TMS) in 10 healthy volunteers before and during administration of sub-anaesthetic doses of ketamine in an open-label within-subject design. Evoked signal diversity was assessed using the perturbational complexity index (PCI), calculated from EEG responses to TMS perturbations. Signal diversity of spontaneous EEG, with eyes open and eyes closed, was assessed by Lempel Ziv complexity (LZc), amplitude coalition entropy (ACE), and synchrony coalition entropy (SCE). Although no significant difference was found in TMS-evoked complexity (PCI) between the sub-anaesthetic ketamine condition and normal wakefulness, all measures of spontaneous EEG signal diversity (LZc, ACE, SCE) showed significantly increased values in the sub-anaesthetic ketamine condition. This increase in signal diversity correlated with subjective assessment of altered states of consciousness. Moreover, spontaneous signal diversity was significantly higher when participants had eyes open compared to eyes closed, both during normal wakefulness and during influence of sub-anaesthetic ketamine. The results suggest that PCI and spontaneous signal diversity may reflect distinct, complementary aspects of changes in brain properties related to altered states of consciousness: the brain’s capacity for information integration, assessed by PCI, might be indicative of the brain’s ability to sustain consciousness, while spontaneous complexity, as measured by EEG signal diversity, may be indicative of the complexity of conscious content. Thus, sub-anaesthetic ketamine may increase the complexity of the conscious content and the brain activity underlying it, while the level or general capacity for consciousness remains largely unaffected.
Improving young children’s handwashing behaviour and understanding of germs: The impact of A Germ’s Journey educational resources in schools and public spaces
Authors: Younie Sarah , Mitchell Chloe , Bisson Marie-Josee , Crosby Sapphire , Kukona Anuenue , Laird Katie
Published: November 2020

Context

Effective handwashing can prevent the spread of germs, including Covid-19. However, young children can lack a fundamental understanding of germ transfer. A Germ’s Journey educational resources were designed to support young children in learning about germs and handwashing. These resources include a book, website, song, online games and glo-gel activities that are informed by a behaviour change model.

Research gap

Prior research has not evaluated the impacts of these resources on behavioural outcomes.

Purpose of the study

Two intervention studies evaluated the impacts of these resources on both knowledge and behavioural outcomes.

Method

In Study 1, children (n = 225) were recruited from four schools and randomly assigned by classrooms to participate in a multicomponent intervention (vs. control). In Study 2, children (n = 104) were recruited from a museum and randomly assigned to participate in a song intervention (vs. control). Trained observers recorded participants’ engagement in six handwashing behaviours and their understanding of germs. These behavioural and knowledge outcomes were analysed using regression and related analyses.

Results

In Study 1, significant improvements were observed between baseline and follow up in the intervention group for both behavioural scores (Est= 0.48,SE= 0.14,t= 3.30,p= 0.001) and knowledge scores (Est= 2.14,SE= 0.52,z= 4.11,p< 0.001), whereas these improvements were not observed in the control group (ts < 1). In Study 2, the intervention group had significantly higher behavioural scores compared to the control group (Est. = -0.71,SE= 0.34,t= -2.07,p= 0.04).

Conclusion

This research demonstrates that specifically designed hand hygiene educational resources can improve handwashing practice and understanding in young children, and could lead to the reduction of the transmission of disease within this group.
Identification of toxic mold species through Raman spectroscopy of fungal conidia
Authors: Strycker Benjamin D. , Han Zehua , Duan Zheng , Commer Blake , Wang Kai , Shaw Brian D. , Sokolov Alexei V. , Scully Marlan O.
Published: November 2020

We use a 785 nm shifted excitation Raman difference (SERDS) technique to measure the Raman spectra of the conidia of 10 mold species of especial toxicological, medical, and industrial importance, including Stachybotrys chartarum, Penicillium chrysogenum, Aspergillus fumigatus, Aspergillus flavus, Aspergillus oryzae, Aspergillus niger, and others. We find that both the pure Raman and fluorescence signals support the hypothesis that for an excitation wavelength of 785 nm the Raman signal originates from the melanin pigments bound within the cell wall of the conidium. In addition, the major features of the pure Raman spectra group into profiles that we hypothesize may be due to differences in the complex melanin biosynthesis pathways. We then combine the Raman spectral data with neural network models to predict species classification with an accuracy above 99%. Finally, the Raman spectral data of all species investigated is made freely available for download and use.
Continuous ultrafiltration during extracorporeal circulation and its effect on lactatemia: A randomized controlled trial
Authors: García-Camacho Carlos , Marín-Paz Antonio-Jesús , Lagares-Franco Carolina , Abellán-Hervás María-José , Sáinz-Otero Ana-María
Published: November 2020

Introduction

Hyperlactatemia occurs during or after extracorporeal circulation in the form of lactic acidosis, increasing the risk of postoperative complications and the mortality rate. The aim of this study was to evaluate whether continuous high-volume hemofiltration with volume replacement through a polyethersulfone filter during the extracorporeal circulation procedure decreases postoperative lactatemia and its consequences.

Materials and methods

This was a randomized controlled trial. Patients were randomly divided into two groups of 32: with or without continuous high-volume hemofiltration through a polyethersulfone membrane. Five patients were excluded from each group during the study period. The sociodemographic characteristics, filter effects, and blood lactate levels at different times during the procedure were evaluated. Secondary endpoints were studied, such as the reduction in the intubation time and time spent in ICU.

Results

Lactatemia measurements performed during the preoperative and intraoperative phases were not significantly different between the two groups. However, the blood lactate levels in the postoperative period and at 24 hours in the intensive care unit showed a significant reduction and a possible clinical benefit in the hemofiltered group. Following extracorporeal circulation, the mean lactate level was higher (difference: 0.77 mmol/L; CI 0.95: 0.01–1.53) in the nonhemofiltered group than in the hemofiltered group (p<0.05). This effect was greater at 24 hours (p = 0.019) in the nonhemofiltered group (difference: 1.06 mmol/L; CI 0.95: 0.18–1.93) than in the hemofiltered group. The reduction of lactatemia is associated with a reduction of inflammatory mediators and intubation time, with an improvement in liver function.

Conclusions

The use and control of continuous high-volume hemofiltration through a polyethersulfone membrane during heart-lung surgery could potencially prevent postoperative complications. The reduction of lactatemia implied a reduction in intubation time, a decrease in morbidity and mortality in the intensive care unit and a shorter hospital stay.
The enactment of physician-authors in Nobel Prize nominations
Authors: Hansson Nils , Nilsson Peter M. , Fangerau Heiner , Wistrand Jonatan
Published: November 2020

Several physicians have been nominated for the Nobel Prize in literature, but so far none of them have received it. Because physicians as women and men of letters have been a major topic of feuilletons, seminars and books for many years, questions arise to what extent medicine was a topic in the proposals for the Nobel Prize and in the Nobel jury evaluations: how were the nominees enacted (or not) as physicians, and why were none of them awarded? Drawing on nomination letters and evaluations by the Nobel committee for literature collected in the archive of the Swedish Academy in Stockholm, this article offers a first overview of nominated physician-author candidates. The focus is on the Austrian historian of medicine Max Neuburger (1868–1955), the German novelist Hans Carossa (1878–1956), and the German poet Gottfried Benn (1886–1956), but it also briefly takes further physician-author nominees into account such as Sigmund Freud (1856–1939) and William Somerset Maugham (1874–1965). The article is part of an interdisciplinary medical humanities project that analyses nominations and committee reports for physicians and natural scientists nominated for the Nobel Prize from 1901 to 1970.
Spatial pattern of perinatal mortality and its determinants in Ethiopia: Data from Ethiopian Demographic and Health Survey 2016
Authors: Yadeta Tesfaye Assebe , Mengistu Bizatu , Gobena Tesfaye , Regassa Lemma Demissie
Published: November 2020

Background

The perinatal mortality rate in Ethiopia is among the highest in Sub Saharan Africa. The aim of this study was to identify the spatial patterns and determinants of perinatal mortality in the country using a national representative 2016 Ethiopia Demographic and Health Survey (EDHS) data.

Methods

The analysis was completed utilizing data from 2016 Ethiopian Demographic and Health Survey. This data captured the information of 5 years preceding the survey period. A total of 7230 women who at delivered at seven or more months gestational age nested within 622 enumeration areas (EAs) were used. Statistical analysis was performed by using STATA version 14.1, by considering the hierarchical nature of the data. Multilevel logistic regression models were fitted to identify community and individual-level factors associated with perinatal mortality. ArcGIS version 10.1 was used for spatial analysis. Moran’s, I statistics fitted to identify global autocorrelation and local autocorrelation was identified using SatSCan version 9.6.

Results

The spatial distribution of perinatal mortality in Ethiopia revealed a clustering pattern. The global Moran’s I value was 0.047 with p-value <0.001. Perinatal mortality was positively associated with the maternal age, being from rural residence, history of terminating a pregnancy, and place of delivery, while negatively associated with partners’ educational level, higher wealth index, longer birth interval, female being head of household and the number of antenatal care (ANC) follow up.

Conclusions

In Ethiopia, the perinatal mortality is high and had spatial variations across the country. Strengthening partner’s education, family planning for longer birth interval, ANC, and delivery services are essential to reduce perinatal mortality and achieve sustainable development goals in Ethiopia. Disparities in perinatal mortality rates should be addressed alongside efforts to address inequities in maternal and neonatal healthcare services all over the country.
Collaborative multicenter logistics delivery network optimization with resource sharing
Authors: Deng Shejun , Yuan Yingying , Wang Yong , Wang Haizhong , Koll Charles
Published: November 2020

Collaboration among logistics facilities in a multicenter logistics delivery network can significantly improve the utilization of logistics resources through resource sharing including logistics facilities, vehicles, and customer services. This study proposes and tests different resource sharing schemes to solve the optimization problem of a collaborative multicenter logistics delivery network based on resource sharing (CMCLDN-RS). The CMCLDN-RS problem aims to establish a collaborative mechanism of allocating logistics resources in a manner that improves the operational efficiency of a logistics network. A bi-objective optimization model is proposed with consideration of various resource sharing schemes in multiple service periods to minimize the total cost and number of vehicles. An adaptive grid particle swarm optimization (AGPSO) algorithm based on customer clustering is devised to solve the CMCLDN-RS problem and find Pareto optimal solutions. An effective elite iteration and selective endowment mechanism is designed for the algorithm to combine global and local search to improve search capabilities. The solution of CMCLDN-RS guarantees that cost savings are fairly allocated to the collaborative participants through a suitable profit allocation model. Compared with the computation performance of the existing nondominated sorting genetic algorithm-II and multi-objective evolutionary algorithm, AGPSO is more computationally efficient. An empirical case study in Chengdu, China suggests that the proposed collaborative mechanism with resource sharing can effectively reduce total operational costs and number of vehicles, thereby enhancing the operational efficiency of the logistics network.
Improved yellow-green split fluorescent proteins for protein labeling and signal amplification
Authors: Zhou Shuqin , Feng Siyu , Brown David , Huang Bo
Published: November 2020

The flexibility and versatility of self-complementing split fluorescent proteins (FPs) have enabled a wide range of applications. In particular, the FP1-10/11 split system contains a small fragment that facilitates efficient generation of endogenous-tagged cell lines and animals as well as signal amplification using tandem FP11 tags. To improve the FP1-10/11 toolbox we previously developed, here we used a combination of directed evolution and rational design approaches, resulting in two mNeonGreen (mNG)-based split FPs (mNG3A1-10/11 and mNG3K1-10/11) and one mClover-based split FP (CloGFP1-10/11). mNG3A1-10/11 and mNG3K1-10/11 not only enhanced the complementation efficiency at low expression levels, but also allowed us to demonstrate signal amplification using tandem mNG211 fragments in mammalian cells.
Burkholderia collagen-like protein 8, Bucl8, is a unique outer membrane component of a putative tetrapartite efflux pump in Burkholderia pseudomallei and Burkholderia mallei
Authors: Grund Megan E. , Choi Soo J. , McNitt Dudley H. , Barbier Mariette , Hu Gangqing , LaSala P. Rocco , Cote Christopher K. , Berisio Rita , Lukomski Slawomir
Published: November 2020

Bacterial efflux pumps are an important pathogenicity trait because they extrude a variety of xenobiotics. Our laboratory previously identified in silico Burkholderia collagen-like protein 8 (Bucl8) in the hazardous pathogens Burkholderia pseudomallei and Burkholderia mallei. We hypothesize that Bucl8, which contains two predicted tandem outer membrane efflux pump domains, is a component of a putative efflux pump. Unique to Bucl8, as compared to other outer membrane proteins, is the presence of an extended extracellular region containing a collagen-like (CL) domain and a non-collagenous C-terminus (Ct). Molecular modeling and circular dichroism spectroscopy with a recombinant protein, corresponding to this extracellular CL-Ct portion of Bucl8, demonstrated that it adopts a collagen triple helix, whereas functional assays screening for Bucl8 ligands identified binding to fibrinogen. Bioinformatic analysis of the bucl8 gene locus revealed it resembles a classical efflux-pump operon. The bucl8 gene is co-localized with downstream fusCDE genes encoding fusaric acid (FA) resistance, and with an upstream gene, designated as fusR, encoding a LysR-type transcriptional regulator. Using reverse transcriptase (RT)-qPCR, we defined the boundaries and transcriptional organization of the fusR-bucl8-fusCDE operon. We found exogenous FA induced bucl8 transcription over 80-fold in B. pseudomallei, while deletion of the entire bucl8 locus decreased the minimum inhibitory concentration of FA 4-fold in its isogenic mutant. We furthermore showed that the putative Bucl8-associated pump expressed in the heterologous Escherichia coli host confers FA resistance. On the contrary, the Bucl8-associated pump did not confer resistance to a panel of clinically-relevant antimicrobials in Burkholderia and E. coli. We finally demonstrated that deletion of the bucl8-locus drastically affects the growth of the mutant in L-broth. We determined that Bucl8 is a component of a novel tetrapartite efflux pump, which confers FA resistance, fibrinogen binding, and optimal growth.
Molecular detection and species identification of Plasmodium spp. infection in adults in the Democratic Republic of Congo: A population-based study
Authors: Kiyonga Aimeé Kahindo , Lengu Thierry Bobanga , Nsibu Célestin Ndosimao , Umesumbu Solange Efundu , Ngoyi Dieudonné Mumba , Chen Tie
Published: November 2020

Background

In efforts to control malaria infection, the Democratic Republic of Congo has implemented several strategies. Studies assessing their efficiency mainly involved at-risk groups, especially children under five years of age. This study aimed to determine the prevalence and identify the risk factors associated with Plasmodium spp. infection.

Methods

From October 2014 to March 2015, individuals aged at least 15 years were selected randomly and enrolled in a cross-sectional study conducted throughout the country. Microscopy and polymerase chain reaction (PCR) analysis were used for the detection of Plasmodium ssp.

Results

From 2286 individuals recruited, 1870 with valid laboratory results were included in the study for further analysis. The prevalence of Plasmodium spp. infection assessed by microscopy (355/ 1870 (19%) was lower than that estimated by PCR (580/1870 (31%). In addition, the difference between the two results was statistically significant (P < 0.0001). The most prevalent Plasmodium species was P. falciparum, either as mono-infection (96.3%; 95% C.I. 93.9–98.1) or combined with P. malariae (3.7%; 95% C.I. 2.8–5.9). The mean parasite density was 3272739 trophozoites/μL of blood. Women had higher risks of being infected than men (OR 2.03, 95% C.I.: 1.96. 2.62, P = 0.041)].

Conclusion

In this study, the molecular detection and species identification of Plasmodium spp. showed that, despite all efforts for malaria control, malaria remains a public health problem in the Democratic Republic of Congo. The high prevalence and parasite density of Plasmodium spp. in adults make this age group a potential parasitic infectious reservoir for the at-risk groups and supports the need to include this age group in further programs for malaria control.
When does risk outweigh reward? Identifying potential scoring strategies with netball’s new two-point rule
Authors: Fox Aaron S. , Bruce Lyndell
Published: November 2020

Changing rules to promote scoring through more ‘high-risk’ play has become common in team sports. Australia’s national netball league (i.e. Suncorp Super Netball) has recently taken this approach–introducing a two-point shooting rule. Teams will be awarded two-points for shots made from an ‘outer circle’ 3.0m-4.9m from the goal in the final five minutes of quarters. We sought to answer a series of questions regarding the implementation and potential strategies surrounding the two-point rule in Suncorp Super Netball. We used video coded data from the 2018 Suncorp Super Netball season to identify the total number of made and missed shots from different distances across the season. We also used shooting statistics from recent Fast5 Netball World Series (a competition with a two-point shooting rule already in place) as a comparator. The reward of two-points is relatively well-aligned to the relative risk of missing shots from the proposed outer versus inner circle (2.22 [1.98, 2.48 95% CIs]) based on existing shooting data from Suncorp Super Netball teams. We found that the relative risk of missing shots from ‘long-’ (i.e. 3.5m-4.0m) versus ‘mid-range’ (i.e. 3.0–3.5m) was only slightly elevated (1.52 [1.21, 1.86 95% CIs])–suggesting teams should favour long- over mid-range shots when the two-point shot is available. Based on the typical number of shots a team receives in a five-minute period, we found that teams may be able to score ~3.51 extra points per quarter when taking all versus no-shots from the two-point outer circle. Analysis of the Fast5 versus Suncorp Super Netball data did, however, reveal that shooting accuracy from long-range may decrease when a two-point shot is available. Teams may need to consider situational factors (e.g. altered opposition defensive strategies) when developing their shooting strategy for taking advantage of the two-point shot.
A worldwide bibliometric analysis of published literature on workplace violence in healthcare personnel
Authors: Cebrino Jesús , Portero de la Cruz Silvia
Published: November 2020

Background

Workplace violence in healthcare professionals has become a worldwide public health problem and has been the focus of numerous publications; however, currently, no macroscopic overviews of this research based on bibliometric analysis have been carried out. Therefore, the main aim of this study was to analyse the research trends focusing on workplace violence in healthcare personnel over the last 27 years.

Materials and methods

A bibliometric study was conducted from 1992 to 2019 in the field of workplace violence in healthcare personnel using the Scopus database. The author co-citation analysis was carried out using VOSviewer software. A worldwide map was created with Mapchart and word cloud image was created using Wordart. Descriptive and inferential statistics were applied.

Findings

1791 records were analysed, 1376 of which (76.83%) were articles, with “Medicine” the most frequent subject category (58.91%). English was the predominant language (93.41%). From 2004 onwards, there was an exponential rise in the number of publications (R2 coefficient = 0.89; p < 0.0001) and the number of annual citations gradually increased from 1995 (R2 coefficient = 0.73; p < 0.0001). The University of Cincinnati (United States) was the institution (and country) with the highest number of publications (n = 30; n = 549), with D. M. Gates leading the ranking of the most productive authors (n = 21). Journal of Nursing Management was the most active journal publishing on the topic (n = 34) and the commonest keyword was “human/s” (16.43%).

Conclusion

From 1992 to 2019, worldwide research into the published literature on workplace violence in healthcare personnel has grown steadily year by year, both in the number of documents and the number of citations. United States and their institutions and researchers dominates this research output.
Becoming and being a biobank donor: The role of relationships and ethics
Authors: Mezinska Signe , Kaleja Jekaterina , Mileiko Ilze
Published: November 2020

Relational aspects, such as involvement of donor’s relatives or friends in the decision-making on participation in a research biobank, providing relatives’ health data to researchers, or sharing research findings with relatives should be considered when reflecting on ethical aspects of research biobanks. The aim of this paper is to explore what the role of donor’s relatives and friends is in the process of becoming and being a biobank donor and which ethical issues arise in this context. We performed qualitative analysis of 40 qualitative semi-structured interviews with biobank donors and researchers. The results show that relatedness to relatives or other types of close relationships played a significant role in the donors’ motivation to be involved in a biobank, risk-benefit assessment, and decisions on sharing information on research and its results. Interviewees mentioned ethical issues in the context of sharing relatives’ health-related data for research purposes and returning research findings that may affect their relatives. We conclude that the question of what information on family members may be shared with a biobank by research participants without informed consent of those relatives, and when family members become research subjects, lacks a clear answer and detailed guidelines, especially in the context of the introduction of the European Union’s (EU) General Data Protection Regulation. Researchers in Latvia and EU face ethical questions and dilemmas about returning research results and incidental findings to donors’ relatives, and donors need more information on sharing research results with relatives in the informed consent process.