bluuebunny/crossref_metadata_2025 huggingface dataset:
Crazy ants craving calcium: macronutrients and micronutrients can limit and stress an invaded grassland brown food web
Authors: Reihart Ryan W. , Angelos Kiersten P. , Gawkins Kaitlin M. , Hurst Shania E. , Montelongo Denise C. , Laws Angela N. , Pennings Steven C. , Prather Chelse M.
Published: December 2020

Nitrogen and phosphorus are thought to be the most important limiting nutrients in most terrestrial ecosystems, but little is known about how other elements may limit the abundance of arthropods. We utilized a fully factorial fertilization experiment that manipulated macronutrients (N and P, together) and micronutrients (calcium, sodium, potassium, separately), in large 30 × 30 m plots and sampled litter arthropods via pitfall trapping to determine the nutrients that limit this group. An invasive ant, Nylanderia fulva, numerically dominated the community and increased in abundance 13% in plots fertilized by Ca. Detritivores were not limited by any nutrient combination, but macronutrients increased predator abundance 43%. We also found that some combinations of macronutrients and micronutrients had toxic or stressful effects on the arthropod community: detritivores decreased in abundance 23% with the combination of macronutrients, Ca, and K, and 22% with macronutrients and K; and N. fulva decreased in abundance 24% in plots fertilized by K and 45% in plots fertilized by the combination of Na and K. Our work supports growing evidence that micronutrients, especially Ca and K, may be important in structuring grassland arthropod communities, and suggests that micronutrients may affect whether or not invasive ants reach numerical dominance.
Two Faces of Neutrophils in Liver Disease Development and Progression
Authors: Cho Yeonhee , Szabo Gyongyi
Published: December 2020

Neutrophils, the most abundant type of leukocyte in human blood, play a major role in host defense against invading pathogens and in sterile injury. Neutrophil infiltration is characteristic of inflammation because of its antimicrobial and cytotoxic activities. Neutrophils also actively participate in the resolution of inflammation and subsequent tissue repair by acting as a critical mediator between the inflammation and resolution phases of tissue damage. However, neutrophils that are consistently exposed to inflammatory conditions lose their self‐resolving capabilities and maintain an inflammatory phenotype, further exacerbating tissue damage. The current review describes how neutrophils interact with tissue microenvironments and acquire disease‐specific phenotypes under chronic inflammatory conditions. Here, we aim to provide a better understanding of neutrophil‐mediated pathogenesis of various liver diseases.
Adaptive extreme learning machine ‐ Fuzzy system framework for energy optimization of IOTs in wireless sensor networks
Authors: Subramaniam Nachimuthu Deepa , I Jasmine Selvakumari Jeya , Baladhandapani Aruna Devi
Published: December 2020

In this paper, a new adaptive extreme learning machine (ELM) neural network‐Fuzzy system framework is developed for effective and efficient network energy optimization of internet‐of‐things (IoTs) sensor nodes in wireless sensor networks (WSNs). Each sensor nodes in a WSN communicates with one another in varied methods to transfer the data from IoT cloud to the other virtual modes. Optimization of IoTs in sensor networks tends to handle the network energy and accuracy with the help of extremely complex clustering techniques. Henceforth, this paper has developed a novel adaptive ELM‐Fuzzy system framework to handle the network energy level in an optimum way and thus achieving better data accuracy and network throughput by reducing the overhead of the network to the maximum possible. Numerical simulations carried out proves the consistency and efficacy of the modeled novel adaptive ELM‐ Fuzzy system framework for IoT based sensor network on comparing with traditional techniques from previous literatures.
Effect of Low-Intensity Vibration on Bone Strength, Microstructure, and Adiposity in Pre-Osteoporotic Postmenopausal Women: A Randomized Placebo-Controlled Trial
Authors: Rajapakse Chamith S , Johncola Alyssa J , Batzdorf Alexandra S , Jones Brandon C , Al Mukaddam Mona , Sexton Kelly , Shults Justine , Leonard Mary B , Snyder Peter J , Wehrli Felix W
Published: December 2020

There has been evidence that cyclical mechanical stimulation may be osteogenic, thus providing opportunities for nonpharmacological treatment of degenerative bone disease. Here, we applied this technology to a cohort of postmenopausal women with varying bone mineral density (BMD) T-scores at the total hip (−0.524 ± 0.843) and spine (−0.795 ± 1.03) to examine the response to intervention after 1 year of daily treatment with 10 minutes of vibration therapy in a randomized double-blinded trial. The device operates either in an active mode (30 Hz and 0.3 g) or placebo. Primary endpoints were changes in bone stiffness at the distal tibia and marrow adiposity of the vertebrae, based on 3 Tesla high-resolution MRI and spectroscopic imaging, respectively. Secondary outcome variables included distal tibial trabecular microstructural parameters and vertebral deformity determined by MRI, volumetric and areal bone densities derived using peripheral quantitative computed tomography (pQCT) of the tibia, and dual-energy X-ray absorptiometry (DXA)-based BMD of the hip and spine. Device adherence was 83% in the active group (n = 42) and 86% in the placebo group (n = 38) and did not differ between groups (p = .7). The mean 12-month changes in tibial stiffness in the treatment group and placebo group were +1.31 ± 6.05% and −2.55 ± 3.90%, respectively (group difference 3.86%, p = .0096). In the active group, marrow fat fraction significantly decreased after 12 months of intervention (p = .0003), whereas no significant change was observed in the placebo group (p = .7; group difference −1.59%, p = .029). Mean differences of the changes in trabecular bone volume fraction (p = .048) and erosion index (p = .044) were also significant, as was pQCT-derived trabecular volumetric BMD (vBMD; p = .016) at the tibia. The data are commensurate with the hypothesis that vibration therapy is protective against loss in mechanical strength and, further, that the intervention minimizes the shift from the osteoblastic to the adipocytic lineage of mesenchymal stem cells. © 2020 American Society for Bone and Mineral Research (ASBMR).
Superposition of waves or densities: Which is the nature of chemical resonance?
Authors: Wang Yang
Published: December 2020

Resonance is a fundamental and widely used concept in chemistry, but there exist two distinct theories of chemical resonance, based on quite different and incompatible premises: the wave‐function‐based resonance theory (WFRT), assuming the superposition of wave functions, versus the density‐matrix‐based resonance theory (DMRT), which interprets the resonance phenomenon as the superposition of density matrices. The latter theory, best known to the chemistry community as the natural resonance theory (NRT), has received much more popularity than the WFRT. In this contribution, the DMRT is shown to be inherently inadequate: (i) the exact density matrix expansion is mathematically impossible unless unphysical negative weights are introduced; (ii) any approximate density matrix representing the resonance hybrid lacks the idempotent property. Therefore, the validity of the NRT ansatz should be seriously questioned. The WFRT seems the only reasonable explanation of resonance so far, and has been shown to provide valuable insights into diverse chemical problems.
The m6A methyltransferase METTL14 inhibits the proliferation, migration, and invasion of gastric cancer by regulating the PI3K/AKT/mTOR signaling pathway
Authors: Liu Xin , Xiao Mingyang , Zhang Liang , Li Liuli , Zhu Guolian , Shen Erdong , Lv Mingyue , Lu Xiaobo , Sun Zhe
Published: December 2020

Background

N6‐methyladenosine (m6A) modification may participate in the regulation of occurrence and development of tumors. However, the m6A level and the potential regulatory mechanism of m6A in gastric cancer (GC) remain uncertain.

Methods

RNA m6A quantification assay was conducted to detect the m6A level in GC tissues and cell lines. Methyltransferase‐like 14 (METTL14) expression in GC tissues was explored by bioinformatics and immunohistochemistry. Then, the function of METTL14 in GC cells was examined by CCK‐8, colony formation assay, wound healing assay, and Transwell assay. Besides, Western blotting was conducted to probe the PI3K/AKT/mTOR pathway and the epithelial‐mesenchymal transformation (EMT) pathway‐related gene expression.

Results

The m6A modification level was decreased in GC and METTL14 was a key regulator resulting in m6A disorder in GC. METTL14 was downregulated in GC by analyzing both clinical samples and bioinformatics. METTL14 overexpression suppressed GC cell proliferation and aggression by deactivating the PI3K/AKT/mTOR pathway and the EMT pathway, respectively.

Conclusions

Our findings indicate that METTL14 partakes in the biological process of GC as a tumor suppressor and may be an emerging biomarker in GC.
Indigenous youth reconnect with cultural identity: The evaluation of a community‐ and school‐based traditional music program
Authors: Good Arla , Sims Lori , Clarke Keith , Russo Frank A.
Published: December 2020

Reconnecting Indigenous youth with their cultural traditions has been identified as an essential part of healing the intergenerational effects of forced assimilation policies. Past work suggests that learning the music of one's culture can foster cultural identity and community bonding, which may serve as protective factors for well‐being. An 8‐week traditional song and dance program was implemented in a school setting for Indigenous youth. An evaluation was conducted using a mixed‐method design to determine the impact of the program on 35 youth in the community. A triangulation of qualitative and quantitative data revealed several important themes, including personal development, cultural development, social development, student engagement in school‐based programming, and perpetuating cultural knowledge. The program provided students with an opportunity to connect with their cultural traditions through activities that encouraged self and cultural expression. Community responses suggested that this type of programming is highly valued among Indigenous communities.
Synthesis, biological evaluation, and molecular docking studies of novel pyrazole, pyrazoline‐clubbed pyridine as potential antimicrobial agents
Authors: Desai Nisheeth C. , Vaja Darshita V. , Monapara Jahnvi D. , Manga Vijjulatha , Vani Tamalapakula
Published: December 2020

We have prepared 15 hybrid pyrazole, pyrazoline‐clubbed pyridine–containing compounds (5a‐o) and tested for their antibacterial and antifungal activities for the development of potential antimicrobial agents. The structures of this novel series were characterized by various spectral techniques like IR, 1H NMR, 13C NMR, LC–MS, and elemental analysis. The synthesized compounds 5d, 5e, 5i, 5k, 5m, and 5o exhibited significant antimicrobial activity in the comparison of standard drugs. Molecular docking studies that have been carried out to emphasize the binding orientations of these molecules were in good compliance with crystal structure interactions. The predicted drug‐likeness (ADME) properties were found to be in the acceptable range.
24‐Month HIV‐free survival among HIV‐exposed Infants in Lesotho: the PEAWIL cohort study
Authors: Tukei Vincent J , Machekano Rhoderick , Gill Michelle M , Tiam Appolinaire , Mokone Majoalane , Isavwa Anthony , Nyabela Malijane , Mots’oane Tsietso , Nchephe Seipati , Letsie Mosilinyane , Kassaye Seble G , Guay Laura
Published: December 2020

Introduction

Following the implementation of the provision of lifelong antiretroviral therapy to all HIV‐positive pregnant or breastfeeding women for prevention of mother‐to‐child transmission (PMTCT) of HIV by the Kingdom of Lesotho in 2013, we assessed the effectiveness of this approach by evaluating 24‐month HIV‐free survival among HIV‐exposed infants (HEIs).

Methods

We conducted a prospective observational cohort study that enrolled HIV‐positive and HIV‐negative pregnant women, with follow‐up of women and their infants for 24 months after delivery. Participant recruitment started in June 2014 and follow‐up ended in September 2018. Trained nurses collected study information through patient interviews and chart abstraction at enrolment and every three to six months thereafter. Maternal HIV testing, infant mortality, HIV transmission and HIV‐free survival rates were computed using Kaplan–Meier estimation. Cox regression hazard models were used to identify factors associated with infant HIV infection and death.

Results

Between June 2014 and February 2016, we enrolled 653 HIV‐positive and 941 HIV‐negative pregnant women. Twenty‐seven HIV‐negative women acquired HIV during follow‐up. Ultimately, 634 liveborn HEI (382 (52%) male, 303 (48%) female, 3 missing) and 839 who remained HIV‐unexposed (HUIs) (409 (49.0%) male, 426 (51.0%) female, 4 missing) were followed; 550 HEIs and 701 HUIs completed the 24‐month follow‐up period. Of 607 (95.7%) HEIs who were tested for HIV at least once during follow‐up, 17 were found to be HIV‐positive. Two (9.5%) of 21 infants born to mothers who acquired HIV infection during follow‐up were HIV‐positive compared to 15 (2.4%) of 613 HEI born to women with known HIV infection. The risk of HIV transmission from HIV‐positive mothers to their infants by 24 months of age was 2.9% (95% CI: 1.8 to 4.7). The estimated 24‐month mortality rate among HEIs was 6.0% (95% CI: 4.4 to 8.2) compared to 3.8% (95% CI: 2.6 to 5.3) among HUIs (Log‐rank p = 0.065). HIV‐free survival at 24 months was 91.8% (95% CI: 89.2 to 93.7). Lower maternal age and birth weight were independently associated with increased HIV infection or death of infants.

Conclusions

The implementation of lifelong ART for PMTCT in the Lesotho public health system resulted in low HIV transmission, but survival of HEI remains lower than their HIV uninfected counterparts.
A retrofit to enable dynamic steering for transmit arrays without multiple amplifiers
Authors: Sun Chenhao , Patel Kevin , Wilcox Matthew , Dimitrov Ivan E. , Cheshkov Sergey , McDougall Mary , Wright Steven M.
Published: December 2020

Purpose

shimming is an important method for mitigating B1 inhomogeneity in high‐field MRI. Using independent power amplifiers for each transmit (Tx) element is the preferred method for B1 shimming but comes with a high cost. Conversely, the simplest approach to control a Tx array is by using coaxial cables of varying length in the Tx chain, but this approach is cumbersome and impractical for dynamic shimming. In this article, a system is described that enables dynamic, phase‐only, eight‐channel steering on a 7T MR scanner with only two power amplifiers.

Methods

Power dividers were utilized to first split the existing two‐channel Tx signal into eight channels. Digitally controlled phase shifters on each channel were designed to provide independent phase shifts with a resolution of 22.5° (from 0°, 22.5° … 337.5°). To validate the system, an eight‐channel body dipole array was simulated and constructed for bench and 7T imaging and evaluation.

Results

The phase conjugate steering method was employed at three different spatial positions in simulation, bench measurements, and scanner measurements—all with matching results. At the desired points, regions with homogenous were generated, indicating good Tx steering to the selected region.

Conclusion

The described system can be used as a simple retrofit to existing hardware to provide phase control while avoiding the need to manually switch cables and without requiring independent power amplifiers for each channel, thus demonstrating the ability to perform dynamic shimming with increased degrees of freedom but without significantly increased hardware cost.
Topology optimization for three‐dimensional elastoplastic architected materials using a path‐dependent adjoint method
Authors: Abueidda Diab W. , Kang Ziliang , Koric Seid , James Kai A. , Jasiuk Iwona M.
Published: December 2020

This article introduces a computational design framework for obtaining three‐dimensional (3D) periodic elastoplastic architected materials with enhanced performance, subject to uniaxial or shear strain. A nonlinear finite element model accounting for plastic deformation is developed, where a Lagrange multiplier approach is utilized to impose periodicity constraints. The analysis assumes that the material obeys a von Mises plasticity model with linear isotropic hardening. The finite element model is combined with a corresponding path‐dependent adjoint sensitivity formulation, which is derived analytically. The optimization problem is parametrized using the solid isotropic material penalization method. Designs are optimized for either end compliance or toughness for a given prescribed displacement. Such a framework results in producing materials with enhanced performance through much better utilization of an elastoplastic material. Several 3D examples are used to demonstrate the effectiveness of the mathematical framework.
Characterization of cellulose nano/microfibril reinforced polypropylene composites processed via solid‐state shear pulverization
Authors: Oliveira Gean Henrique M. , Maia Thiago H. S. , Talabi Segun I. , Canto Leonardo B. , Lucas Alessandra A.
Published: December 2020

Polypropylene (PP) composites with cellulose nanofibril (CNF), lignocellulose nanofibril (LCNF) or bleached kraft wood pulp (BWKP) cellulose microfibril compatibilized by maleic anhydride grafted polypropylene were produced by different approaches. Samples containing 10–30 wt% filler were prepared by mixing cellulose aqueous suspensions and PP through solid‐state shear pulverization. The flakes obtained were compounded by twin‐screw melt extrusion (MSE) followed by injection molding (IM) into standard specimens. Reference samples with 30 wt% CNF or LCNF were prepared through a standard procedure, which involved freeze‐drying of nanofibrils aqueous suspensions before MSE and IM, whereas a sample with 30 wt% BWKP was prepared directly by MSE and IM. Injection‐molded specimens were characterized by scanning electron microscopy, differential scanning calorimetry, thermogravimetry, and tensile and notched impact tests. The thermal behavior of the PP matrix in the composites was not significantly affected by the filler type and content and processing route as well. CNF and LCNF reinforced PP composites showed inferior mechanical properties, due to the formation of nanofibrils agglomerates in the PP matrix, regardless of the processing route adopted. Highly filled (30 wt%) BWKP composites presented superior mechanical properties with significant increase in the modulus, tensile strength, and impact strength due to the formation of well‐dispersed microfibrils bundles in the PP matrix. A comparative analysis showed that the composites developed in this study present similar or even superior mechanical performance for given filler content to other natural fiber reinforced PP composites reported in the literature.
Haematological and Biochemical Parameters of Captive Siberian Tigers (Panthera tigris altaica) from the Heilongjiang Province, China
Authors: Liu Enqi , Ma Liying , You Dan , Yang Cen , Hu Yawen , Xu Haitao , Liu Dan , Wang Yajun
Published: December 2020

Haematological and biochemical parameters play important roles in safeguarding animal health and preventing disease, but the blood reference values of many wild animals are still unknown. Recently, few descriptions of the blood parameters of Siberian tigers (Panthera tigris altaica) have been reported because these tigers comprise an endangered species; however, it is extremely difficult to obtain blood samples necessary for these analyses. This study presents 14 haematological and 16 biochemical parameters of 133 Siberian tigers, of which 112 and 21 were from Heilongjiang Siberian Tiger Park (HB) and Hailin Siberian Tiger Park (HD), China, respectively. Our study is the first to determine the following parameters in Siberian tigers: red blood cell volume distribution width, platelet count, mean platelet volume, amylase (AMY), sodium/potassium, globulin and albumin/globulin levels. As the data for total bilirubin and AMY were not statistically significant, no statistical analysis was conducted for these parameters. Few parameters were significantly different according to sex and region (p < 0.05). The concentration of alkaline phosphatase decreased with age, whereas the creatinine (CREA) increased with age. The CREA concentration of tigers raised in HB was much lower than that of tigers raised in HD. The data obtained in this study provide a reference for monitoring the health of wild and captive Siberian tigers and will add important information to the standards for haematological and biochemical parameters of wild felines.
Low-rank parity-check codes over Galois rings
Authors: Renner Julian , Neri Alessandro , Puchinger Sven
Published: December 2020

Low-rank parity-check (LRPC) codes are rank-metric codes over finite fields, which have been proposed by Gaborit et al. (Proceedings of the workshop on coding and cryptography WCC, vol 2013, 2013) for cryptographic applications. Inspired by a recent adaption of Gabidulin codes to certain finite rings by Kamche et al. (IEEE Trans Inf Theory 65(12):7718–7735, 2019), we define and study LRPC codes over Galois rings—a wide class of finite commutative rings. We give a decoding algorithm similar to Gaborit et al.’s decoder, based on simple linear-algebraic operations. We derive an upper bound on the failure probability of the decoder, which is significantly more involved than in the case of finite fields. The bound depends only on the rank of an error, i.e., is independent of its free rank. Further, we analyze the complexity of the decoder. We obtain that there is a class of LRPC codes over a Galois ring that can decode roughly the same number of errors as a Gabidulin code with the same code parameters, but faster than the currently best decoder for Gabidulin codes. However, the price that one needs to pay is a small failure probability, which we can bound from above.
Surveillance of Sentinel Node-Positive Melanoma Patients with Reasons for Exclusion from MSLT-II: Multi-Institutional Propensity Score Matched Analysis
Authors: Broman Kristy K. , Hughes Tasha M. , Dossett Lesly A. , Sun James , Carr Michael J. , Kirichenko Dennis A. , Sharma Avinash , Bartlett Edmund K. , Nijhuis Amanda AG. , Thompson John F. , Hieken Tina J. , Kottschade Lisa , Downs Jennifer , Gyorki David E. , Stahlie Emma , van Akkooi Alexander , Ollila David W. , Frank Jill , Song Yun , Karakousis Giorgos , Moncrieff Marc , Nobes Jenny , Vetto John , Han Dale , Farma Jeffrey , Deneve Jeremiah L. , Fleming Martin D. , Perez Matthew , Baecher Kirsten , Lowe Michael , Bagge Roger Olofsson , Mattsson Jan , Lee Ann Y. , Berman Russell S. , Chai Harvey , Kroon Hidde M. , Teras Roland M. , Teras Juri , Farrow Norma E. , Beasley Georgia M. , Hui Jane YC. , Been Lukas , Kruijff Schelto , Boulware David , Sarnaik Amod A. , Sondak Vernon K. , Zager Jonathan S.
Published: December 2020

BACKGROUND:

In sentinel lymph node (SLN)-positive melanoma, two randomized trials demonstrated equivalent melanoma-specific survival with nodal surveillance vs completion lymph node dissection (CLND). Patients with microsatellites, extranodal extension (ENE) in the SLN, or >3 positive SLNs constitute a high-risk group largely excluded from the randomized trials, for whom appropriate management remains unknown.

STUDY DESIGN:

SLN-positive patients with any of the three high-risk features were identified from an international cohort. CLND patients were matched 1:1 with surveillance patients using propensity scores. Risk of any-site recurrence, SLN-basin–only recurrence, and melanoma-specific mortality were compared.

RESULTS:

Among 1,154 SLN-positive patients, 166 had ENE, microsatellites, and/or >3 positive SLN. At 18.5 months median follow-up, 49% had recurrence (vs 26% in patients without high-risk features, p < 0.01). Among high-risk patients, 52 (31%) underwent CLND and 114 (69%) received surveillance. Fifty-one CLND patients were matched to 51 surveillance patients. The matched cohort was balanced on tumor, nodal, and adjuvant treatment factors. There were no significant differences in any-site recurrence (CLND 49%, surveillance 45%, p = 0.99), SLN-basin–only recurrence (CLND 6%, surveillance 14%, p = 0.20), or melanoma-specific mortality (CLND 14%, surveillance 12%, p = 0.86).

CONCLUSIONS:

SLN-positive patients with microsatellites, ENE, or >3 positive SLN constitute a high-risk group with a 2-fold greater recurrence risk. For those managed with nodal surveillance, SLN-basin recurrences were more frequent, but all-site recurrence and melanoma-specific mortality were comparable to patients treated with CLND. Most recurrences were outside the SLN-basin, supporting use of nodal surveillance for SLN-positive patients with microsatellites, ENE, and/or >3 positive SLN.
Stage IIIa Melanoma and Impact of Multiple Positive Lymph Nodes on Survival
Authors: Woeste Matthew R. , McMasters Kelly M. , Egger Michael E.
Published: December 2020

BACKGROUND:

For patients with cutaneous melanoma, having >1 positive lymph node (LN) is associated with worse survival. We hypothesized that for stage IIIA patients, N2a disease (2 to 3 positive LN) would be associated with a worse prognosis compared to those with N1a disease (1 positive LN).

STUDY DESIGN:

Stage IIIA melanoma patients in the NCDB Participant User File from 2010 to 2016 were analyzed. Overall survival (OS) between N1a and N2a patients was compared. Subgroup analyses were made between patients undergoing sentinel lymph node (SLN) biopsy alone and those undergoing subsequent completion lymph node dissection (CLND). A separate post hoc analysis of T2a patients undergoing SLN biopsy and CLND from a prospective multicenter randomized clinical trial was performed to validate the findings.

RESULTS:

Records of 2,305 IIIA patients were evaluated. In an adjusted survival model, N2a disease was an independent risk factor for worse OS (hazard ratio [HR] 1.56, p = 0.0052). In the subgroup analysis, there was no difference in OS between N1a and N2a disease for patients who underwent SLN biopsy without CLND (p = 0.59), but there was a significant difference in OS for patients who underwent SLN biopsy plus CLND (p = 0.0009). The separate clinical trial database confirmed that for patients with SLN-only disease, there was no difference in OS between N1a and N2a disease.

CONCLUSIONS:

For stage IIIA melanoma patients, the distribution of micrometastatic lymph node disease (SLN or non-SLN), rather than the absolute number of SLNs, should be considered when individualizing adjuvant therapy recommendations.
Impact of Preoperative Occult-Bacterial Translocation on Surgical Site Infection in Patients Undergoing Pancreatoduodenectomy
Authors: Suenaga Masaya , Yokoyama Yukihiro , Fujii Tsutomu , Yamada Suguru , Yamaguchi Junpei , Hayashi Masamichi , Asahara Takashi , Nagino Masato , Kodera Yasuhiro
Published: December 2020

BACKGROUND:

Occult-bacterial translocation (O-BT) has been reported as the condition in which microorganisms are detected in blood or lymph nodes by a highly sensitive method. However, the clinical impact of preoperative O-BT on postoperative complication is unclear.

STUDY DESIGN:

A prospective observational study with patients undergoing pancreatoduodenectomy for periampullary diseases was conducted. Blood samples were collected immediately after induction of anesthesia. The status of O-BT was investigated using bacterium-specific ribosomal RNA-targeted reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR). The impact of O-BT on surgical site infection (SSI) was analyzed.

RESULTS:

A total of 155 patients were included. The positive rate in preoperative blood samples detected by RT-qPCR was significantly higher than that obtained by the culture method (32 of 155 vs 4 of 155, p < 0.001). Preoperative blood samples were contaminated with 1.0 to 19.2 bacterial cells/mL in positive patients, and 30 of the 41 detected microorganisms were obligate anaerobes. No differences in preoperative factors were observed between patients with positive and negative RT-qPCR results. The incidence of any SSI was significantly higher in patients with contaminated preoperative blood (≥1.2 bacterial cells/mL) than in other patients (14 of 27 vs 35 of 128, p = 0.013). Multivariable analysis indicated that contaminated preoperative blood was identified as one of the independent risk factors for SSI (odds ratio 2.71, 95% CI 1.04 to 7.24, p = 0.041).

CONCLUSIONS:

O-BT, predominantly with obligate anaerobes, was commonly observed in preoperative blood samples. In addition to the previously known risk factors, O-BT may be one of the risk factors for SSI after pancreatoduodenectomy.
Text Analysis in Python for Social Scientists
Authors: Hovy Dirk
Published: December 2020

Text is everywhere, and it is a fantastic resource for social scientists. However, because it is so abundant, and because language is so variable, it is often difficult to extract the information we want. There is a whole subfield of AI concerned with text analysis (natural language processing). Many of the basic analysis methods developed are now readily available as Python implementations. This Element will teach you when to use which method, the mathematical background of how it works, and the Python code to implement it.
Persistent, Depth‐Intensified Mixing During The Western Mediterranean Transition's Initial Stages
Authors: Piñeiro S. , González‐Pola C. , Fernández‐Díaz J. M. , Naveira‐Garabato A. C. , Sánchez‐Leal R. , Puig P. , Salat J. , Balbin R.
Published: December 2020

Major deep‐convection activity in the northwestern Mediterranean during winter 2005 triggered the formation of a complex anomalous deep‐water structure that substantially modified the properties of the Western Mediterranean deep layers. Since then, evolution of this thermohaline structure, the so‐called Western Mediterranean Transition (WMT), has been traced through a regularly sampled hydrographic deep station located on the outer continental slope of Minorca Island. A rapid erosion of the WMT's near‐bottom thermohaline signal was observed during 2005–2007. The plausible interpretation of this as local bottom‐intensified mixing motivates this study. Here, the evolution of the WMT structure through 2005–2007 is reproduced by means of a one‐dimensional diffusion model including double‐diffusive mixing that allows vertical variation of the background mixing coefficient and includes a source term to represent the lateral advection of deep‐water injections from the convection area. Using an optimization algorithm, a best guess for the depth‐dependent background mixing coefficient is obtained for the study period. WMT evolution during its initial stages is satisfactorily reproduced using this simple conceptual model, indicating that strong depth‐intensified mixing (K

∞
(z) ≈ 22 × 10−4 m2 s−1; z ⪆ 1,400 dbar) is a valid explanation for the observations. Extensive hydrographic and current observations gathered over the continental slope of Minorca during winter 2018, the first deep‐convective winter intensively sampled in the region, provide evidence of topographically localized enhanced mixing concurrent with newly formed dense waters flowing along‐slope toward the Algerian sub‐basin. This transport‐related boundary mixing mechanism is suggested to be a plausible source of the water‐mass transformations observed during the initial stages of the WMT off Minorca.
Lightning and Secondary Convection in the Anvil of the May 29, 2012 Oklahoma Supercell Storm Observed by DC3
Authors: DiGangi E. A. , Ziegler C. L. , MacGorman D. R.
Published: December 2020

A supercell thunderstorm formed as part of a cluster of severe storms near Kingfisher, Oklahoma on May 29, 2012 during the Deep Convective Clouds and Chemistry field experiment. This storm produced 5 hail, an EF‐1 tornado, and copious lightning over the course of a few hours within range of the Oklahoma Lightning Mapping Array and the KTLX WSR‐88D radar. This study focuses on a ∼1‐h interval during which a line of secondary convection formed and intensified within the anvil of the Kingfisher supercell. An analysis of radar reflectivity, radial velocity, and low‐level divergence shows that the formation of the secondary convection was consistent with a previously proposed mechanism; the instability leading to the convection was initiated by diabatic cooling in dry air below the anvil from sublimation, melting and evaporation of virga falling from the anvil, coincident with weak rising motion above a surface outflow boundary adjacent to the sub‐anvil downdraft. Prior to the formation of the secondary convection, flashes extended up to 60 km from the deep convection into the anvil. After the line of secondary convection formed, it initiated long lightning flashes that propagated along the line, and it continued to produce lightning as it moved eastward out from under the anvil. The charge structure inferred from flashes in the parent storm and in the downstream anvil suggests that charge was separated locally in the anvil following the development of an outflow boundary by the Kingfisher storm, which also contributed to the initiation of the secondary convection.
Event‐Based Evaluation of the GPM Multisatellite Merged Precipitation Product From 2014 to 2018 Over China: Methods and Results
Authors: Li Runze , Wang Kaicun , Qi Dan
Published: December 2020

Evaluations of satellite precipitation products have been routinely conducted, often by calculating statistical indicators on fixed time intervals (e.g., hourly and daily). However, precipitation is actually a discontinuous variable in the form of events. Event‐based evaluations could provide additional information to those based on fixed‐interval statistics but have rarely been done. To address this issue, the Integrated MultisatellitE Retrievals for Global Precipitation Measurement (GPM) (IMERG) V06B product is evaluated with hourly rain gauge data from approximately 50,000 stations in China. We first assess the feasibility of using a satellite product to delineate precipitation event properties and then track satellite errors with the evolution of precipitation processes. Our results show a strong positive relationship between event duration and mean intensity in IMERG, which is not obvious in the gauge data. IMERG presents weaker peak‐to‐mean intensity ratio and later peak occurrence time than compared to the gauge data. Higher false alarm and lower miss proportions exist near the beginning of an event in IMERG, and this pattern reverses near the end of the event. IMERG underestimates the precipitation rate at the beginning of an event but overestimates later. The IMERG bias in event properties revealed here has important implication on its applications like flood forecasting and storm identification, and the life cycle‐dependent performance of IMERG we found indicates the need of event dynamics and stage information in satellite precipitation retrieval processes, which is not in current algorithms. The event‐based evaluation carried out here can be applied to other satellite precipitation products as well.
Experimental Investigation of Apollo 16 “Rusty Rock” Alteration by a Lunar Fumarolic Gas
Authors: Renggli C. J. , Klemme S.
Published: December 2020

The Apollo 16 sample 66095, named “Rusty Rock”, is enriched in volatile and moderately volatile elements. The impact melt breccia is characterized by abundant Fe‐rich sulfide and chloride alteration phases, including FeS, ZnS, and FeCl2. These phases have previously been interpreted to be the result of fumarolic alteration of the breccia. Here we present the results of two different experimental approaches, which aim to constrain the temperature conditions and the process under which the “Rusty Rock” alteration formed. The first experimental set‐up assumes that the metals Zn, Cu, and Fe were introduced into the rock by a C‐O‐S‐Cl gas phase, and that the Fe‐rich sulfides and chlorides were deposited from this gas phase. This “gas deposition” experiment suggests that the alteration assemblage formed over the temperature range of 538–638 ± 5°C. The second experimental set‐up simulates a scenario, where Fe metal particles in the lunar rock react with a Zn‐C‐O‐S‐Cl gas phase at six different temperatures between 396 ± 5°C and 1,005 ± 5°C. This latter “metal reaction” experiment resulted in the formation of sulfide and chloride coatings on the Fe metal chips. The “Rusty Rock” alteration phases FeCl2 and (Zn,Fe)S were abundantly present in the coating of the Fe metal chip reacted at 580 ± 10°C. Both experiments lead to results which are in agreement, providing a temperature of 580 ± 50°C for the fumarolic alteration on the Moon, as observed in the Apollo 16 “Rusty Rock”.
Addressing Gaps in Space Weather Operations and Understanding With Small Satellites
Authors: Verkhoglyadova O. P. , Bussy‐Virat C. D. , Caspi A. , Jackson D. R. , Kalegaev V. , Klenzing J. , Nieves‐Chinchilla J. , Vourlidas A.
Published: December 2020

Gaps in space weather observations that can be addressed with small satellites are identified. Potential improvements in solar inputs to space weather models, space radiation control, estimations of energy budget of the upper Earth's atmosphere, and satellite drag modeling are briefly discussed. Key observables, instruments, and observation strategies by small satellites are recommended. Tracking optimization for small satellites is proposed.
A non-luminescent polymorph of [(cyclohexyl isocyanide)2Au]PF6 that becomes luminescent upon grinding or exposure to dichloromethane vapor
Authors: Luong Lucy M. C. , Olmstead Marilyn M. , Balch Alan L.
Published: December 2020

Colorless crystals of the new non-luminescent polymorph of [(C6H11NC)2Au]PF6 (3) become luminescent upon grinding or exposure to dichloromethane vapour.
„Das Vertrauen in die normale Geburt ist die Grundhaltung im Hebammenkreißsaal“
Authors: Bosch Andrea , Becker Marion Anna
Published: December 2020

Experten-Interview | Theorie-Praxis-Transfer ist keine Einbahnstraße. Das weiß Hebamme und Diplom-Pflegewirtin Andrea Bosch aus 35 Jahren Praxis im Kreißsaal. Für DIE HEBAMME blickt sie zurück auf ein Herzensprojekt, das sie 2007 als leitende Hebamme zusammen mit ihrem Team am Klinikum Stuttgart in die Tat umgesetzt hat: den Hebammenkreißsaal der größten Geburtsklinik Baden-Württembergs. Sie schildert die Herausforderungen und Entwicklungen des Projekts und beschreibt, wie sie und ihr Team Theorie in die Praxis gebracht haben.
Theorie-Praxis-Relationierung mit dem Ansatz der Schlüssel-situationen. Oder: Wie wär’s mit einem Tango Professional, Madame?
Authors: Tov Eva
Published: December 2020

Im vorliegenden Artikel setzt die Autorin Theorie und Praxis miteinander ins Verhältnis. Sie stellt dafür das Reflexionsmodell Schlüsselsituationen vor, das auf bedeutsamen Situationen der Sozialen Arbeit beruht. Theoretische Grundlage des Modells bildet der Ansatz des situierten und erfahrungsbasierten Lernens, den sie hier anhand von Beispielen der Hebammenarbeit erläutert.
Erkennen fetaler Wachstumsretardierung – das GAP-Programm als neues Tool in der hebammengeleiteten Schwangerenvorsorge
Authors: Grabbert Jella
Published: December 2020

Das in England entwickelte Growth Assessment Protocol (GAP) unterstützt die Erkennung fetaler Wachstumsretardierung und konnte in britischen Studien die Totgeburtenrate deutlich senken. Für Hebammen ist das GAP-Programm ein zuverlässiges Instrument, um das fetale Wachstum zu beurteilen und Auffälligkeiten sicher zu identifizieren. Die Autorin des vorliegenden Artikels ist Ansprechpartnerin für GAP in Deutschland und setzt sich dafür ein, die Umsetzung des Programms für deutschsprachige Hebammen zu erleichtern.
Characterizing the second wave of fish and invertebrate colonization of an offshore petroleum platform
Authors: Todd Victoria L G , Susini Irene , Williamson Laura D , Todd Ian B , McLean Dianne L , Macreadie Peter I
Published: December 2020

Offshore Oil and Gas (O&G) infrastructure affords structurally complex hard substrata in otherwise featurless areas of the seafloor. Opportunistically collected industrial ROV imagery was used to investigate the colonization of a petroleum platform in the North Sea 1–2 years following installation. Compared to pre-construction communities and pioneering colonizers, we documented 48 additional taxa, including a rare sighting of a pompano (Trachinotus ovatus). The second wave of motile colonizers presented greater diversity than the pioneering community. Occurrence of species became more even over the 2 years following installation, with species occurring in more comparable abundances. No on-jacket sessile taxa were recorded during first-wave investigations; however, 17 sessile species were detected after 1 year (decreasing to 16 after 2). Motile species were found to favour structurally complex sections of the jacket (e.g. mudmat), while sessile organisms favoured exposed elements. Evidence of on-jacket reproduction was found for two commercially important invertebrate species - common whelk (Buccinum undatum) and European squid (Loligo vulgaris). Moreover, abundance of larvae-producing species experience an 8.5-fold increase over a 2-year period compared to baseline communities. These findings may have implications for decommissioning and resource-management strategies, suggesting that a case-by-case reviewing approach should be favoured over the most common “one size fits all”.
Inhomogeneous Diophantine Approximation onM0-Sets with Restricted Denominators
Authors: Pollington Andrew D , Velani Sanju , Zafeiropoulos Agamemnon , Zorin Evgeniy
Published: December 2020

Let $F \subseteq [0,1]$ be a set that supports a probability measure $\mu $ with the property that $ |\widehat{\mu }(t)| \ll (\log |t|)^{-A}$ for some constant $ A> 0 $. Let $\mathcal{A}= (q_n)_{n\in{\mathbb{N}}} $ be a sequence of natural numbers. If $\mathcal{A}$ is lacunary and $A>2$, we establish a quantitative inhomogeneous Khintchine-type theorem in which (1) the points of interest are restricted to $F$ and (2) the denominators of the “shifted” rationals are restricted to $\mathcal{A}$. The theorem can be viewed as a natural strengthening of the fact that the sequence $(q_nx \textrm{mod} 1)_{n\in{\mathbb{N}}} $ is uniformly distributed for $\mu $ almost all $x \in F$. Beyond lacunary, our main theorem implies the analogous quantitative result for sequences $\mathcal{A}$ for which the prime divisors are restricted to a finite set of $k$ primes and $A> 2k$. Loosely speaking, for such sequences, our result can be viewed as a quantitative refinement of the fundamental theorem of Davenport, Erdös, and LeVeque (1963) in the theory of uniform distribution.
How Many Cases Are Easy?
Authors: Fischman Joshua B
Published: December 2020

Because judges are expected to decide cases through the impartial application of existing law, they are often reluctant to admit that they must make law in hard cases. Many judges claim that such hard cases are rare, constituting roughly 10 percent of cases. In stark contrast, economic models of the selection of disputes for litigation predict that easy cases will settle, so that only hard cases would remain in trial and appellate courts. Empirical indicators, such as dissent rates or voting differences between Democratic and Republican appointees, have yielded muddled conclusions about the proportion of easy and hard cases in appellate courts. In fact, none of these crude statistics relate directly to the proportion of easy cases. This article develops a new approach for empirically analyzing the proportion of easy cases. Although the easiness and hardness of cases are subjective, it is possible to estimate feasible combinations of the proportion of hard cases and clear errors. This approach relies only on the basic premise that reasonable judges should not disagree in easy cases. The article then illustrates this approach using two datasets of appeals. An analysis of asylum appeals in the 9th Circuit finds widespread disagreement, implying high proportions of hard cases, clear errors, or both. By contrast, voting data from labor and environmental cases in the D.C. Circuit is consistent with the claim that 90 percent of cases are easy and 1 percent of decisions are clear errors.
Cholera in travellers: improving vaccination guidance in Europe
Authors: López-Vélez Rogelio , Presotto Danilo
Published: December 2020

Background

Cholera is endemic in ~50 countries worldwide and remains a disease associated with poverty, causing illness and death in the poorest and most vulnerable people. In travellers, cholera is considered a low-incidence disease, but the true impact on travellers is difficult to assess. Cholera vaccination may improve safety for certain European travellers at risk. Effective vaccines are available; however, vaccination recommendations in Europe vary considerably between countries.

Methods

In this review, a comparison of cholera vaccination recommendations from 29 advice reference bodies across key European countries (United Kingdom, Germany, Spain, Italy, Portugal, Switzerland, Sweden, Finland, Norway, France and Denmark) is presented. The differences in perceived cholera risk are highlighted, and a comparison with the United States Centers for Disease Control and Prevention (CDC) recommendations is included.

Results

In general terms, the recommendations from European organizations are ambiguous and differ widely. This contrasts with the situation in the United States, where the CDC publishes a consistent set of guidelines.

Conclusion

With the ease of intra-European travel, it would seem sensible to harmonize the recommendations for cholera vaccination and risk perception across Europe, providing pre-travel health advisers with a trusted source of information that allows them to provide consistent recommendations.
An atypical BRCT–BRCT interaction with the XRCC1 scaffold protein compacts human DNA Ligase IIIα within a flexible DNA repair complex
Authors: Hammel Michal , Rashid Ishtiaque , Sverzhinsky Aleksandr , Pourfarjam Yasin , Tsai Miaw-Sheue , Ellenberger Tom , Pascal John M , Kim In-Kwon , Tainer John A , Tomkinson Alan E
Published: December 2020

The XRCC1–DNA ligase IIIα complex (XL) is critical for DNA single-strand break repair, a key target for PARP inhibitors in cancer cells deficient in homologous recombination. Here, we combined biophysical approaches to gain insights into the shape and conformational flexibility of the XL as well as XRCC1 and DNA ligase IIIα (LigIIIα) alone. Structurally-guided mutational analyses based on the crystal structure of the human BRCT–BRCT heterodimer identified the network of salt bridges that together with the N-terminal extension of the XRCC1 C-terminal BRCT domain constitute the XL molecular interface. Coupling size exclusion chromatography with small angle X-ray scattering and multiangle light scattering (SEC-SAXS–MALS), we determined that the XL is more compact than either XRCC1 or LigIIIα, both of which form transient homodimers and are highly disordered. The reduced disorder and flexibility allowed us to build models of XL particles visualized by negative stain electron microscopy that predict close spatial organization between the LigIIIα catalytic core and both BRCT domains of XRCC1. Together our results identify an atypical BRCT–BRCT interaction as the stable nucleating core of the XL that links the flexible nick sensing and catalytic domains of LigIIIα to other protein partners of the flexible XRCC1 scaffold.