bluuebunny/crossref_metadata_2025 huggingface dataset:
Draft Genome Sequences of 27 Northern Maine Clinical Isolates
Authors: Feinstein Larry , Batchelder Kendra , Tilley Lydia , Stafford Grace
Published: February 2021

We report the draft genome sequences of 27 common pathogens collected from a northern Maine hospital in 2017. These were sequenced in order to determine temporal and biogeographical patterns of antibiotic gene distribution. A total of 908 antibiotic resistance genes, 848 insertion sequence elements, and 57 plasmids were identified.
Draft Genome Sequence of Streptococcus agalactiae TA B490, a Multidrug-Resistant Strain Isolated from Bovine Mastitis in Argentina
Authors: Cadona J. S. , Hernandez L. B. , Lorenzo R. , Bottini E. , Bustamante A. V. , Sanso A. M.
Published: February 2021

Streptococcus agalactiae
is a bovine pathogen that causes intramammary infections. For humans,
S. agalactiae
is a leading cause of neonatal death and an emerging pathogen in adults. Here, we present the draft genome sequence of
S. agalactiae
TA B490, a multidrug-resistant strain isolated from bovine mastitis in Argentina.
Complete Genome Sequence of Burkholderia gladioli Phage Maja
Authors: Yu Zihao , Yao Guichun , Vizoso-Pinto Maria Guadalupe , Sun Lichang , Young Ry , Gonzalez Carlos , Liu Mei
Published: February 2021

Burkholderia gladioli
is a Gram-negative bacterium associated with cystic fibrosis infections. Here, we describe the genome sequence of
B. gladioli
phage Maja. Maja is most related to another
Burkholderia
phage, BcepF1, and may be a temperate phage, despite the absence of repressor or integrase homologs in its genome sequence.
Complete and Circularized Genome Assembly of a Human Isolate of Vibrio navarrensis Biotype
pommerensis
with MiSeq and MinION Sequence Data
Authors: Schwartz Keike , Borowiak Maria , Deneke Carlus , Balau Veronika , Metelmann Claudia , Strauch Eckhard
Published: February 2021

Vibrio navarrensis
is a rare human pathogen. Strains of
Vibrio navarrensis
biotype
pommerensis
were isolated from seawater of the Baltic Sea. Recently, a strain of this biotype was recovered from a human patient. The isolate contains two circular chromosomes and a large plasmid with a size of 180 kb.
Complete Genome Sequence of Klebsiella pneumoniae Strain ATCC 43816
Authors: Budnick James A. , Bina X. Renee , Bina James E.
Published: February 2021

Klebsiella pneumoniae
is a member of
Enterobacteriaceae
that causes a multitude of infections in compromised and healthy individuals. The rise of hypervirulent and multiple-drug-resistant
K. pneumoniae
strains has made this organism a global health threat. Here, we report the complete genome sequence of
K. pneumoniae
strain ATCC 43816.
Complete Genome Sequence of Bradyrhizobium japonicum Podophage Paso
Authors: McBee Dylan , Ravindran Aravind , Newkirk Heather , Burrowes Ben , Young Ry , Gonzalez Carlos
Published: February 2021

Bradyrhizobium japonicum
is a nitrogen-fixing, Gram-negative bacterium that forms a symbiotic relationship with leguminous plants. This announcement describes the isolation and genome annotation of
B. japonicum
T7-like podophage Paso. Genomic analysis reveals genes that are associated with both the T5 and T7 modes of genomic DNA (gDNA) entry into the host.
Complete Genome Sequence of a Phapecoctavirus Isolated from a Pigeon Cloacal Swab Sample
Authors: Khalifeh Anthony , Kraberger Simona , Dziewulska Daria , Stenzel Tomasz , Varsani Arvind
Published: February 2021

The complete genome sequence of a bacteriophage in the genus
Phapecoctavirus
(family
Myoviridae
) isolated from a cloacal swab specimen from a domestic pigeon (
Columba livia
f.
domestica
) was identified using a high-throughput sequencing approach. The genome is 150,892 bp with a GC content of 39.1%, containing 269 open reading frames and 11 tRNA genes.
Broadening quantum cosmology with a fractional whirl
Authors: Rasouli S. M. M. , Jalalzadeh S. , Moniz P. V.
Published: February 2021

We start by presenting a brief summary of fractional quantum mechanics, as means to convey a motivation towards fractional quantum cosmology. Subsequently, such application is made concrete with the assistance of a case study. Specifically, we investigate and then discuss a model of stiff matter in a spatially flat homogeneous and isotropic universe. A new quantum cosmological solution, where fractional calculus implications are explicit, is presented and then contrasted with the corresponding standard quantum cosmology setting.
Confronting dual models of the strong interaction
Authors: Ridkokasha I.
Published: February 2021

Studies of the mathematical properties of Regge-pole and dual amplitudes are important both for their applications in high energy phenomenology and in their generalizations to strings, superstrings, branes, and other theoretical developments. In this paper, we investigate the similarities and differences between two classes of dual amplitudes: one with Mandelstam analyticity (DAMA) and another one with logarithmic trajectories (Dual-log). By using quantum (q-) deformations, new features of Dual-log amplitude are unveiled, in particular those concerning its asymptotic behavior and the spectrum of resonances. The two classes of dual amplitudes are compared in various kinematic regions: at fixed transferred momenta asymptotic, fixed angle asymptotic, and in the resonance region.
Numerical analysis of effective refractive index ultrasonic sensor based on Cantilever arm structure slot-based dual-micro-ring resonator
Authors: zhao C. Y. , Li P. Y. , Zhang C. M.
Published: February 2021

We propose a novel ultrasonic sensor structure composed of Cantilever arm structure slot dual-micro-ring resonators (DMRR). We present a theoretical analysis of transmission by using the coupled mode theory. The mode field distributions and sound pressure distributions of transmission spectrum are obtained from 3D simulations based on Comsol Multi-physics (COMSOL) method. Our ultrasonic sensor exhibits theoretical sensitivity as high as [Formula: see text], which is 22 times higher than that of the single slot-based micro-ring ultrasonic sensor. Our ultrasonic sensor offers higher sensitivity and a larger detection frequency range than conventional piezoelectric-based ultrasound transducer. The results show that the sensing characteristics of our system can be optimized through changing the position and the angle of sound field. Our ultrasonic sensor is with an area of [Formula: see text], the [Formula: see text]-factor can be approximately [Formula: see text] with radius of [Formula: see text]. We detect an angular range of [Formula: see text] to [Formula: see text] and a minimum distance of [Formula: see text]. Finally, we calculate the Cantilever arm structure slot DMRR array ultrasonic sensor’s optical performance. Our proposed design provides a promising candidate for a hydrophone.
Elderly fall due to drowsiness: detection and prevention using machine learning and IOT
Authors: Kumar Vinod , Badal Neelendra , Mishra Rajesh
Published: February 2021

For gauging the drowsiness, various algorithms have been proposed, but the maximum of approaches tries to gauge the facial expression and even change in the skin. In this paper, gauging the landmarks that have been discovered precisely enough to reliably predict the drowsiness was tried using the degree of eye-opening. The suggested algorithm within the paper finds that using the landmarks and eye aspect ratio (EAR) characterizes a person’s eye-opening in each frame. A simple mathematical expression i.e. Euclidean distance finds eye blinks being a blueprint for EAR. Thus, these values help us detect drowsiness. Once the detection happens, other problems arise as to how to send the data to a larger place, as a person may be critical and there is no internet at that place. Then messages cannot be received to a family member. To avoid this situation, nRF is used to facilitate multi-hop communication. Second, this paper focuses on the sleep pattern of an elderly, which is indeed an important aspect of gauging drowsiness. The lack of sleep is very common in the old person. Thus, this aspect helped us to accurately predict the physical condition of the elderly and indeed act as a piece of very useful information in restricting the fall of the elderly. So, for predicting the health of the elderly, we have applied the machine learning model and able to predict the condition of the elderly. The model on real-world scenarios was tested and the results are indeed accurate.
Study on adsorption of CO and CO2by graphene gas sensor
Authors: Tian Wenchao , Niu Jiahao , Li Wenhua , Liu Xiaohan
Published: February 2021

The two-dimensional (2D) plane of graphene has many active sites for gas adsorption. It has broad application prospects in the field of MEMS gas sensors. At present, there are many experimental studies on graphene gas sensors, but it is difficult to accurately control various influencing factors in the experiments. Therefore, this paper applies the first principle based on density functional theory to study the adsorption and detection characteristics of graphene on CO and CO2. The first-principles analysis method was used to study the adsorption characteristics and sensitivity of graphene. The results show that the inductive graphene has a sensitivity of 1.55% and 0.77% for CO and CO2, respectively. The Stone–Wales defects and multi-vacancy defects have greatly improved the sensitivity of graphene to CO, which is 35.25% and 4.14%, respectively. Introduction of defects increases the sensitivity of detection of CO and CO2, but also improves the selective gas detection material of these two gases. Thus, the control and selectively introducing defects may improve the detection accuracy of the graphene CO and CO2.
A Non-Iterative Integration Scheme Enriching the Solution to the Coupled Maglev Vehicle–Bridge System
Authors: Liu Wei , Guo Wenhua
Published: February 2021

A non-iterative integration scheme is presented in this study to enrich the solutions to the coupled equations of the maglev vehicle–bridge system. The proposed integration scheme is composed of two integration methods aiming at providing the solutions to equation of motion and state-space equation. First, the equation of motion of the simply supported girder bridge is transformed by the modal superposition method. Then the state-space equation is used to describe the motions of both the vehicle and the suspension control system, with the associated matrices assembled using the fully computerized approach. By adopting this integration scheme, only pure vector calculations arise in the solution process, regardless of the existence of time-dependent displacement and velocity on the right-hand sides of the two coupled equations. The proposed integration method is of the second-order accuracy with and without damping. Being equipped with adequate numerical dissipation and dispersion, the method also possesses the characteristic of little computing errors, as can be achieved through the use of different pairs of parameters. Finally, numerical simulations have been conducted to assess the influence of different feedback gains, three types of bridges with different lengths, and guideway irregularity on the maglev vehicle–bridge system.
Chapter 3.2b Bransfield Strait and James Ross Island: petrology
Authors: Haase Karsten M. , Beier Christoph
Published: February 2021

Young volcanic centres of the Bransfield Strait and James Ross Island occur along back-arc extensional structures parallel to the South Shetland island arc. Back-arc extension was caused by slab rollback at the South Shetland Trench during the past 4 myr. The variability of lava compositions along the Bransfield Strait results from varying degrees of mantle depletion and input of a slab component. The mantle underneath the Bransfield Strait is heterogeneous on a scale of approximately tens of kilometres with portions in the mantle wedge not affected by slab fluids. Lavas from James Ross Island east of the Antarctic Peninsula differ in composition from those of the Bransfield Strait in that they are alkaline without evidence for a component from a subducted slab. Alkaline lavas from the volcanic centres east of the Antarctic Peninsula imply variably low degrees of partial melting in the presence of residual garnet, suggesting variable thinning of the lithosphere by extension. Magmas in the Bransfield Strait form by relatively high degrees of melting in the shallow mantle, whereas the magmas some 150 km further east form by low degrees of melting deeper in the mantle, reflecting the diversity of mantle geodynamic processes related to subduction along the South Shetland Trench.
Resilience in Development and Psychopathology: Multisystem Perspectives
Authors: Masten Ann S. , Lucke Cara M. , Nelson Kayla M. , Stallworthy Isabella C.
Published: February 2021

Resilience science in psychology and related fields emerged from clinical research on risk for psychopathology in the 1970s and matured over the ensuing decades with advances in theory, methods, and knowledge. Definitions and models of resilience shifted to reflect the expanding influence of developmental systems theory and the growing need to integrate knowledge about resilience across levels and disciplines to address multisystem threats. Resilience is defined for scalability and integrative purposes as the capacity of a dynamic system to adapt successfully through multisystem processes to challenges that threaten system function, survival, or development. Striking alignment of resilience factors observed in human systems, ranging from individuals to communities, suggests the possibility of networked, multisystem protective factors that work in concert. Evidence suggests that there may be resilience factors that provide transdiagnostic protection against the effects of adverse childhood experiences on risk for psychopathology. Multisystem studies of resilience offer promising directions for future research and its applications to promote mental health and positive development in children and youth at risk for psychopathology.
Koopman Operators for Estimation and Control of Dynamical Systems
Authors: Otto Samuel E. , Rowley Clarence W.
Published: February 2021

A common way to represent a system's dynamics is to specify how the state evolves in time. An alternative viewpoint is to specify how functions of the state evolve in time. This evolution of functions is governed by a linear operator called the Koopman operator, whose spectral properties reveal intrinsic features of a system. For instance, its eigenfunctions determine coordinates in which the dynamics evolve linearly. This review discusses the theoretical foundations of Koopman operator methods, as well as numerical methods developed over the past two decades to approximate the Koopman operator from data, for systems both with and without actuation. We pay special attention to ergodic systems, for which especially effective numerical methods are available. For nonlinear systems with an affine control input, the Koopman formalism leads naturally to systems that are bilinear in the state and the input, and this structure can be leveraged for the design of controllers and estimators.
Exercise-induced alterations in phospholipid hydrolysis, airway surfactant, and eicosanoids and their role in airway hyperresponsiveness in asthma
Authors: Murphy Ryan C. , Lai Ying , Nolin James D. , Aguillon Prada Robier A. , Chakrabarti Arindam , Novotny Michael V. , Seeds Michael C. , Altemeier William A. , Gelb Michael H. , Hite Robert Duncan , Hallstrand Teal S.
Published: February 2021

The mechanisms responsible for driving endogenous airway hyperresponsiveness (AHR) in the form of exercise-induced bronchoconstriction (EIB) are not fully understood. We examined alterations in airway phospholipid hydrolysis, surfactant degradation, and lipid mediator release in relation to AHR severity and changes induced by exercise challenge. Paired induced sputum ( n = 18) and bronchoalveolar lavage (BAL) fluid ( n = 11) were obtained before and after exercise challenge in asthmatic subjects. Samples were analyzed for phospholipid structure, surfactant function, and levels of eicosanoids and secreted phospholipase A2group 10 (sPLA2-X). A primary epithelial cell culture model was used to model effects of osmotic stress on sPLA2-X. Exercise challenge resulted in increased surfactant degradation, phospholipase activity, and eicosanoid production in sputum samples of all patients. Subjects with EIB had higher levels of surfactant degradation and phospholipase activity in BAL fluid. Higher basal sputum levels of cysteinyl leukotrienes (CysLTs) and prostaglandin D2(PGD2) were associated with direct AHR, and both the postexercise and absolute change in CysLTs and PGD2levels were associated with EIB severity. Surfactant function either was abnormal at baseline or became abnormal after exercise challenge. Baseline levels of sPLA2-X in sputum and the absolute change in amount of sPLA2-X with exercise were positively correlated with EIB severity. Osmotic stress ex vivo resulted in movement of water and release of sPLA2-X to the apical surface. In summary, exercise challenge promotes changes in phospholipid structure and eicosanoid release in asthma, providing two mechanisms that promote bronchoconstriction, particularly in individuals with EIB who have higher basal levels of phospholipid turnover.
Progesterone-induced blocking factor improves blood pressure, inflammation, and pup weight in response to reduced uterine perfusion pressure (RUPP)
Authors: Cottrell Jesse N. , Witcher Alexis C. , Comley Kyleigh , Cunningham Jr. Mark W. , Ibrahim Tarek , Cornelius Denise C. , LaMarca Babbette , Amaral Lorena M.
Published: February 2021

Preeclampsia (PE) is characterized by new-onset hypertension in association with elevated natural killer (NK) cells and inflammatory cytokines, which are likely culprits for decreased fetal weight during PE pregnancies. As progesterone increases during normal pregnancy, it stimulates progesterone-induced blocking factor (PIBF). PIBF has been shown to decrease inflammation and cytolytic NK cells, both of which are increased during PE. We hypothesized that PIBF reduces inflammation as a mechanism to improve hypertension in the preclinical reduced uterine perfusion pressure (RUPP) rat model of PE. PIBF (2.0 µg/mL) was administered intraperitoneally on gestational day 15 to either RUPP or normal pregnant (NP) rats. On day 18, carotid catheters were inserted. Mean arterial blood pressure (MAP) and samples were collected on day 19. MAP in NP rats ( n = 11) was 100 ± 2 mmHg and 105 ± 3 mmHg in NP + PIBF rats ( n = 8) and 122 ± 1 mmHg in RUPP rats ( n = 10), which improved to 110 ± 2 mmHg in RUPP + PIBF rats ( n = 11), P < 0.05. Pup weight was 2.4 ± 0.1 g in NP, 2.5 ± 0.1 g in NP + PIBF, 1.9 ± 0.1 g in RUPP, and improved to 2.1 ± 0.1 g in RUPP + PIBF rats. Circulating and placental cytolytic NK cells, IL-17, and IL-6 were significantly reduced while IL-4 and T helper (TH) 2 cells were significantly increased in RUPP rats after PIBF administration. Importantly, vasoactive pathways preproendothelin-1, nitric oxide, and soluble fms-Like tyrosine Kinase-1 (sFlt-1) were normalized in RUPP + PIBF rats compared with RUPP rats, P < 0.05. Our findings suggest that PIBF normalized IL-4/TH2 cells, which was associated with improved inflammation, fetal growth restriction, and blood pressure in the RUPP rat model of PE.
Plasma volume contraction reduces atrial natriuretic peptide after four days of hypobaric hypoxia exposure
Authors: Gatterer Hannes , Rauch Simon , Regli Ivo B. , Woyke Simon , Schlittler Maja , Turner Rachel , Strapazzon Giacomo , Brugger Hermann , Goetze Jens P. , Feraille Eric , Siebenmann Christoph
Published: February 2021

We investigated whether low arterial oxygen tension ([Formula: see text]) or hypoxia-induced plasma volume (PV) contraction, which reduces central blood volume (BV) and atrial distension, explain reduction in circulating atrial natriuretic peptide (ANP) after prolonged hypoxic exposure. Ten healthy males were exposed for 4 days to hypobaric hypoxia corresponding to an altitude of 3,500 m. PV changes were determined by carbon monoxide rebreathing. Venous plasma concentrations of midregional proANP (MR-proANP) were measured before and at the end of the exposure. At the latter time point, the measurement was repeated after 1) restoration of [Formula: see text] by breathing a hyperoxic gas mixture for 30 min and 2) restoration of BV by fluid infusion. Correspondingly, left ventricular end-diastolic volume (LVEDV), left atrial area (LAA), and right atrial area (RAA) were determined by ultrasound before exposure and both before and after fluid infusion at the end of the exposure. Hypoxic exposure reduced MR-proANP from 37.9 ± 18.5 to 24.5 ± 10.3 pmol/L ( P = 0.034), LVEDV from 107.4 ± 33.5 to 91.6 ± 26.3 mL ( P = 0.005), LAA from 15.8 ± 4.9 to 13.3 ± 4.2 cm2 ( P = 0.007), and RAA from 16.2 ± 3.1 to 14.3 ± 3.5 cm2 ( P = 0.001). Hyperoxic breathing did not affect MR-proANP (24.8 ± 12.3 pmol/L, P = 0.890). Conversely, fluid infusion restored LVEDV, LAA, and RAA to near-baseline values (108.0 ± 29.3 mL, 17.2 ± 5.7 cm2, and 17.2 ± 3.1 cm2, respectively, P > 0.05 vs. baseline) and increased MR-proANP to 29.5 ± 13.3 pmol/L ( P = 0.010 vs. preinfusion and P = 0.182 vs. baseline). These findings support that ANP reduction in hypoxia is at least partially attributed to plasma volume contraction, whereas reduced [Formula: see text] does not seem to contribute.
Strongly directional responses to tones and conspecific calls in the auditory nerve of the Tokay gecko, Gekko gecko
Authors: Christensen-Dalsgaard Jakob , Kuokkanen Paula , Matthews Jamie Emoto , Carr Catherine E.
Published: February 2021

In mammals, the two ears are unconnected pressure receivers, and sound direction is computed from binaural interactions in the brain, but in lizards, the eardrums interact acoustically, producing a strongly directional response. We show strongly lateralized responses from gecko auditory nerve fibers to directional sound stimulation and high Fisher information on either side of the midline. Thus, already the auditory nerve provides a population code for sound source direction in the gecko.
Expectations about motion direction affect perception and anticipatory smooth pursuit differently
Authors: Wu Xiuyun , Rothwell Austin C. , Spering Miriam , Montagnini Anna
Published: February 2021

We show that expectations about motion direction that are based on long-term trial history affect perception and anticipatory pursuit differently. Whereas anticipatory pursuit direction was coherent with the expected motion direction (attraction bias), perception was biased opposite to the expected direction (repulsion bias). These opposite biases potentially reveal different ways in which perception and action utilize prior information and support the idea of different information processing for perception and pursuit.
Active vision at the foveal scale in the primate superior colliculus
Authors: Hafed Ziad M. , Chen Chih-Yang , Tian Xiaoguang , Baumann Matthias P. , Zhang Tong
Published: February 2021

The primate superior colliculus (SC) has recently been shown to possess both a large foveal representation as well as a varied visual processing repertoire. This structure is also known to contribute to eye movement generation. Here, we describe our current understanding of how SC visual and movement-related signals interact within the realm of small eye movements associated with the foveal scale of visuomotor behavior. Within the SC’s foveal representation, there is a full spectrum of visual, visual-motor, and motor-related discharge for fixational eye movements. Moreover, a substantial number of neurons only emit movement-related discharge when microsaccades are visually guided, but not when similar movements are generated toward a blank. This represents a particularly striking example of integrating vision and action at the foveal scale. Beyond that, SC visual responses themselves are strongly modulated, and in multiple ways, by the occurrence of small eye movements. Intriguingly, this impact can extend to eccentricities well beyond the fovea, causing both sensitivity enhancement and suppression in the periphery. Because of large foveal magnification of neural tissue, such long-range eccentricity effects are neurally warped into smaller differences in anatomical space, providing a structural means for linking peripheral and foveal visual modulations around fixational eye movements. Finally, even the retinal-image visual flows associated with tiny fixational eye movements are signaled fairly faithfully by peripheral SC neurons with relatively large receptive fields. These results demonstrate how studying active vision at the foveal scale represents an opportunity for understanding primate vision during natural behaviors involving ever-present foveating eye movements.
Calcitriol Supplementation Ameliorates Microvascular Endothelial Dysfunction in Vitamin D‐Deficient Diabetic Rats by Upregulating the Vascular eNOS Protein Expression and Reducing Oxidative Stress
Authors: Wee Chee Lee , Mokhtar Siti Safiah , Singh Kirnpal Kaur Banga , Yahaya Sahran , Leung Susan Wai Sum , Rasool Aida Hanum Ghulam
Published: February 2021

Diabetes mellitus contributes to macro‐ and microvascular complications, leading to adverse cardiovascular events. This study examined the effects of vitamin D deficiency on the vascular function and tissue oxidative status in the microcirculation of diabetic rats and to determine whether these effects can be reversed with calcitriol (active vitamin D metabolite) supplementation. Streptozotocin‐induced diabetic rats were fed for 10 weeks with control diet (DC) or vitamin D‐deficient diet without (DD) or with oral calcitriol supplementation (0.15 μg/kg) in the last four weeks (DDS) (10 rats each group). A nondiabetic rat group that received control diet was also included (NR). After 10 weeks, rats were sacrificed; mesenteric arterial rings with and without endothelium were studied using wire myograph. Western blotting of the mesenteric arterial tissue was performed to determine the protein expression of endothelial nitric oxide synthase (eNOS) enzyme. Antioxidant enzyme superoxide dismutase (SOD) activity and oxidative stress marker malondialdehyde (MDA) levels in the mesenteric arterial tissue were also measured. The DC group had significantly lower acetylcholine‐induced relaxation and augmented endothelium‐dependent contraction, with reduced eNOS expression, compared to NR rats. In mesenteric arteries of DD, acetylcholine‐induced endothelium‐dependent and sodium nitroprusside‐induced endothelium‐independent relaxations were lower than those in DC. Calcitriol supplementation in DDS restored endothelium‐dependent relaxation. Mesenteric artery endothelium‐dependent contraction of DD was greater than DC; it was not affected by calcitriol supplementation. The eNOS protein expression and SOD activity were significantly lower while MDA levels were greater in DD compared to DC; these effects were not observed in DDS that received calcitriol supplementation. In conclusion, vitamin D deficiency causes eNOS downregulation and oxidative stress, thereby impairing the vascular function and posing an additional risk for microvascular complications in diabetes. Calcitriol supplementation to diabetics with vitamin D deficiency could potentially be useful in the management of or as an adjunct to diabetes‐related cardiovascular complications.
An Efficient Semianalytical Modal Analysis of Rectangular Waveguides Containing Metamaterials with Graded Inhomogeneity
Authors: Weng Qianru , Lin Qian , Wu Haifeng
Published: February 2021

Rectangular waveguides containing inhomogeneous metamaterials with graded refractive-index profiles have potential applications in bending waveguides and radiation-enhanced antennas, and accurate eigenvalue solutions are prerequisite. Commonly used commercial electromagnetic solvers such as HFSS, COMSOL, and CST could not efficiently calculate the eigenvalues of waveguides containing graded refractive-index dielectrics. In this paper, an accurate and efficient semianalytical method based on the modal expansion has been proposed to solve these waveguides. The proposed method has been employed to calculate the eigenvalues, including the cutoff wavenumbers and dispersion relations, for metamaterials with various graded refractive-index profiles. Calculated results are then validated by comparison, using commercial solver HFSS, which indicates the superiority of the proposed method in accuracy and efficiency. Below-cutoff backward wave propagation is observed in waveguides filled with graded refractive-index metamaterials, which provides a new approach for waveguide miniaturization.
Modelling of Formation Pore Pressure Inversion during Tight Reservoir Drilling
Authors: Sun Xiaohui , Liao Youqiang , Wang Zhiyuan , Zhao XinXin , Sun Baojiang
Published: February 2021

Identifying and controlling a kicking well hinge on quickly obtaining reliable and accurate formation pore pressure. In this study, we derive an analytical model for estimating formation pore pressure when a gas kick occurs during tight reservoir drilling. The model considers the variations in gas volume and pressures in the annulus affected by mutual coupling between the wellbore and formation, as well as bubble migration and expansion in the annulus. Additionally, a numerical computation method that reduces the effect of measurement noise using the Hooke-Jeeves algorithm is proposed. The method is capable of estimating pore pressure during the early stage of a kick in real time, is robust to the inherit noise of the measurements, and can be applied in scenarios when a well shut-in process cannot be performed. The simulation results demonstrate that both kick simulation and formation pore pressure inversion can be conducted via the proposed methodology. The errors of the pore pressure estimating results are less than 2.03% compared to the field data of seven wells. The method is tested and validated to be robust to noise and maintain good convergence performance, thereby providing drilling engineers with a simple and quick way to estimate pore pressure during a kick.
Plugging and Its Stability Evaluation for the Ore Pass in the Nonempty Condition Based on Controllable Grouting of Cement-Sodium Silicate Grout
Authors: Yuan Ye , Qiao Dengpan , Yu Shibo
Published: February 2021

Aimed at the problem to plug the main ore pass with the large collapse at Xingshan Iron Mine, the viscosity-time test and the heap perfusion test of cement-silicate grout in a loose rock mass are carried out. The relationship between the vertical diffusion distance of cement-silicate grout and setting time of grout is studied, and research results are applied to the design of plugging engineering of the main ore pass in -330 m. Based on the numerical simulation of the plugging structure and the long-term stress monitoring of the cable sensors, the stability of the plugging structure itself and the control for the movement of shafts nearby are comprehensively evaluated. The test results show that for a specific loose rock mass, the vertical diffusion distance of cement-silicate grout in the loose rock mass is a power function of grout setting time. Based on the design concept to plug the main ore pass with the large collapse using artificially constructed “bite-bonded arch,” the plugging design and construction procedures are proposed. A numerical model and long-term monitoring of cable stress show that the plugging structure is stable and has an obvious effect on the control movement of abutment shafts.
The Spatiotemporal Characteristics of Coupling Effect between Roof and Backfill Body in Dense Backfill Mining
Authors: Zhao Xinyuan , Li Xinwang , Yang Ke , Wei Zhen
Published: February 2021

Backfill mining has become an important part of coal mine green mining technology. In this paper, the spatiotemporal characteristics of coupling effect between the roof and dense backfill body were analyzed by theoretical analysis and similar simulation test, and Xingtai Mine in China was taken as an engineering case for verification. The results show that the larger subsidence of the roof is, the stronger the supporting capacity of the backfill body is, and the interaction between the two is more obvious, thus showing a coupling effect. This coupling effect presents a regular variation with the increase of backfill distance and time, that is, the coupling degree of roof and backfill body is high in the middle of goaf and low in the vicinity of the coal pillar in spatial distribution, and the coupling behavior of roof and backfill body continues to occur slowly with time. Through the monitoring of stress and displacement in the engineering site and the analysis of borehole observation results, the spatiotemporal coupling effect between roof subsidence and backfill support is fully verified. The research results are of great significance to the control of surrounding rock in backfill mining, the study of the mechanical aging characteristics of backfilling materials, and the optimization of backfill body support performance.
Study on Seepage Simulation of High Pressure Grouting in Microfractured Rock Mass
Authors: Wang Kai , Wang Lianguo , Ren Bo , Fan Hao
Published: February 2021

In coal mines, under high in situ stress and strong mining activity, roadway surrounding rock commonly contains large amounts of larger fractures and microfractures. Along with the large deformation and continuous rheology of the soft rock roadway, the fractures in the surrounding rock are likely to be compressed and closed, forming undeveloped microfractures, which hinder conventional grouting support methods. Based on the fluid-solid coupling between slurry seepage and microfracture deformation, a theoretical model of microfracture grouting seepage is established. A program for the analysis and calculation of microfracture grouting is developed to quantitatively describe the variation in slurry seepage distance and fracture opening. Numerical experiments are carried out to study the grouting seepage of microfractures under different grouting pressures and fracture opening conditions, and the variation rules for the spatial distribution of fracture opening and slurry seepage distance during grouting pressure are obtained. Fluid-solid coupling has a significant influence on grout seepage characteristics. The grouting pressure and the fracture opening changes are nonlinearly attenuated along the grout seepage direction.
Recombinant Lactococcus lactis Carrying IL-4 and IL-10 Coding Vectors Protects against Type 1 Diabetes in NOD Mice and Attenuates Insulitis in the STZ-Induced Model
Authors: Preisser Tatiane M. , da Cunha Vanessa P. , Santana Mariana P. , Pereira Vanessa B. , Cara Denise C. , Souza Bianca M. , Miyoshi Anderson
Published: February 2021

Type 1 diabetes (T1D) is an autoimmune disease that culminates in beta cell destruction in the pancreas and, subsequently, deficiency in insulin production. Cytokines play a crucial role in the development of diabetes, orchestrating the recruitment and action of immune cells, to not only destroy insulin-producing cells but also preserve them. Therefore, the aim of this study was to investigate the effect of orally administered Lactococcus lactis MG1363 FnBPA+ strains carrying plasmids encoding IL-4 and IL-10 in the streptozotocin- (STZ-) induced diabetes model and in nonobese diabetic (NOD) mice. The STZ-induced mice that were treated with combined bacterial strains carrying plasmids encoding IL-4 and IL-10 showed lower incidence of diabetes and more preserved pancreatic islets than the mice that received the individual bacterial strains. Combined administration of L. lactis MG1363 FnBPA+ (pValac::dts::IL-4) and L. lactis MG1363 FnBPA+ (pValac::IL-10) resulted in protection against diabetes in NOD mice. It was shown that the combined treatment with recombinant bacterial by oral route prevented hyperglycemia and reduced the pancreatic islets-destruction in NOD mice. In addition, increased levels of IL-4 and IL-10 in serum and pancreatic tissue revealed a systemic effect of the treatment and also favored an anti-inflammatory microenvironment. Reduced concentrations of IL-12 in pancreas were essential to the regulation of inflammation, resulting in no incidence of diabetes in treated NOD mice. Normal levels of intestinal sIgA after long-term treatment with the L. lactis strains carrying plasmids encoding IL-4 and IL-10 indicate the development of oral tolerance and corroborate the use of this potent tool of mucosal delivery. For the first time, L. lactis MG1363 FnBPA+ strains carrying eukaryotic expression vectors encoding IL-4 and IL-10 are tested in STZ-induced and NOD mouse models. Therefore, our study demonstrates this innovative strategy provides immunomodulatory potential for further investigations in T1D and other autoimmune diseases.
Prognostic and Therapeutic Utility of Variably Expressed Cell Surface Receptors in Osteosarcoma
Authors: Zvi Yoav , Ugur Elif , Batko Brian , Gill Jonathan , Roth Michael , Gorlick Richard , Hall David , Tingling Janet , Barkauskas Donald A. , Zhang Jinghang , Yang Rui , Hoang Bang H. , Geller David S.
Published: February 2021

Background. Six cell surface receptors, human epidermal growth factor receptor-2 (Her-2), platelet-derived growth factor receptor-β (PDGFR-β), insulin-like growth factor-1 receptor (IGF-1R), insulin receptor (IR), c-Met, and vascular endothelial growth factor receptor-3 (VEGFR-3), previously demonstrated variable expression across varying patient-derived and standard osteosarcoma (OS) cell lines. The current study sought to validate previous expression patterns and evaluate whether these receptors offer prognostic and/or therapeutic value. Methods. Patient-derived OS cell lines (n = 52) were labeled with antibodies to Her-2, PDGFR-β, IGF-1R, IR, c-Met, and VEGFR-3. Expression was characterized using flow cytometry. The difference in geometric mean fluorescent intensity (geoMFIdiff = geoMFIpositive − geoMFInegative) was calculated for each receptor across all cell lines. Receptor expression was categorized as low (Q1), intermediate (Q2, Q3), or high (Q4). The event-free survival (EFS) and overall survival for the six cell surface receptors were estimated by the Kaplan–Meier method. Differences in hazard for EFS event and overall survival event for patients in each of the three expression levels in each of the six cell surface receptors were assessed using the log-rank test. Results. All 6 receptors were variably expressed in the majority of cell lines. IR and PDGFR-β expressions were found to be significant predictors for EFS amongst patients with nonmetastatic disease (

p
=
0.02

and 0.01, respectively). The hazard ratio for EFS was significantly higher between high IR and intermediate IR expression (HR = 2.66,

p
=
0.02

), as well as between high PDGFR-β and intermediate PDGFR-β expression (HR = 5.68,

p
=
0.002

). Her-2, c-Met, IGF-1R, and VEGFR-3 were not found to be significant predictors for either EFS or overall survival. Conclusion. The six cell surface receptors demonstrated variable expression across the majority of patient-derived OS cell lines tested. Limited prognostic value was offered by IR and PDGFR-β expression within nonmetastatic patients. The remaining receptors do not provide clear prognostic utility. Nevertheless, their consistent, albeit variable, surface expression across a large panel of patient-derived OS cell lines maintains their potential use as future therapeutic targets.
Knowledge and Behavior‐Driven Fruit Fly Optimization Algorithm for Field Service Scheduling Problem with Customer Satisfaction
Authors: Wu Bin , Jiang Hui-Jun , Wang Chao , Dong Min
Published: February 2021

The field service scheduling problem (FSSP) is the key problem in field services. Field service pays particular attention to customer experience, that is, customer satisfaction. Customer satisfaction described by customer behavior characteristics based on the prospect theory is considered as the primary optimization goal in this paper. The knowledge of the insertion feasibility on the solution is analysed based on the skill constraint and time window. According to the knowledge, an initialization method based on the nearest heuristic algorithm is constructed. Based on the prior knowledge of the FSSP and the endowment of the Fruit Fly Optimization Algorithm, two operators are defined according to the matrix encoding method. Based on these two operators, three search strategies are then proposed, and the smell‐based search strategy and vision‐based search strategy for the FOA are redesigned. To verify the performance of the algorithms, the proposed operators and strategies are tested and analysed in the well‐known benchmark. Through comparison with the state‐of‐the‐art algorithms, the results show that the proposed HFOA is an effective and efficient method to solve the FSSP with customer satisfaction.
Inflammatory Markers in Cerebrospinal Fluid from Patients with Hydrocephalus: A Systematic Literature Review
Authors: Lolansen Sara Diana , Rostgaard Nina , Oernbo Eva Kjer , Juhler Marianne , Simonsen Anja Hviid , MacAulay Nanna
Published: February 2021

Objective. The aim of this systematic review was to evaluate existing literature on inflammatory markers in CSF from patients with hydrocephalus and identify potential markers capable of promoting hydrocephalus development and progression. Methods. Relevant studies published before December 3rd 2020 were identified from PubMed, Embase, and reference lists. Studies were screened for eligibility using the predefined inclusion and exclusion criteria. Data from eligible studies were extracted, and sources of bias were evaluated. We included articles written in English investigating inflammatory markers in CSF from patients with hydrocephalus and control subjects. The review was conducted according to the PRISMA guidelines by three independent reviewers. Results. Twenty-two studies analyzed CSF from 311 patients with idiopathic normal pressure hydrocephalus (iNPH), 178 with posthemorrhagic hydrocephalus (PHH), 151 with other hydrocephalus diagnoses, and 394 control subjects. Fifty-eight inflammatory markers were investigated. The CSF of iNPH patients had increased CSF levels of IL-6, IL-1β, and LRG compared with control subjects, whereas the CSF of PHH patients had increased levels of IL-6, IL-18, and VEGF. CSF from patients with “other hydrocephalus diagnoses” had elevated IFN-γ compared to control subjects, and VEGF was increased in congenital hydrocephalus, spina bifida, and hydrocephalus associated with tuberculous meningitis compared with controls. Conclusion. IL-6, IL-1β, LRG, IL-18, VEGF, and IFN-γ are elevated in CSF from patients with hydrocephalus and may be involved in promotion of hydrocephalus development and progression. They may serve as novel disease biomarkers, and their signaling pathways may represent targets for pharmacological management of hydrocephalus.
Study on Sensitivity Parameters Analysis of Grouting Reinforcement Underpassing Existing Subway Tunnel by Numerical Modeling
Authors: Hu Zaiqiang , Ma Bin , Chen Xingzhou , Chen Lili
Published: February 2021

When carrying out construction that underpasses existing subway tunnels, the surrounding rock is frequently disturbed. Therefore, it can loosen easily and become unstable, which makes its stability difficult to control. Here, we considered an existing subway tunnel in a certain subway section and used orthogonal experiments to design a simulation program as well as the UDEC (Universal Distinct Element Code) simulation software to determine the influences of four factors (i.e., grout density, grouting pressure, dynamic shear force, and viscosity) on the grouting reinforcement effect. The following results were obtained: (1) the combination of the construction method and the grouting parameters strongly influences the reinforcement effect on the surrounding rock of the tunnel. The grouting pressure is not directly proportional to the stability of the surrounding rock. The dynamic adjustment of the relationship between the grouting pressure and the grout density can effectively improve the stress state of the surrounding rock of the tunnel, control surface settlement and deformation, and reduce the section reduction rate of the tunnel. (2) The distribution of joints is closely related to the failure area and form of the surrounding rock of the tunnel. For surrounding rock with well‐developed joint fissures, an excessively high grouting pressure should not be used as they are unstable. (3) The effective bearing range of grouting‐reinforced surrounding rock is dependent on the pore pressure and principal stress difference. The area where the pore pressure is 70–80% of the initial grouting pressure is the effective bearing range of the grouting‐reinforced surrounding rock. The stability of the surrounding rock increases with decreasing principal stress difference and increasing range. (4) The actual monitored data show that the surface settlement can be effectively reduced by handling of grouting reinforcement parameters flexibly, which can meet the control standards.
Identification of biomarkers for tumor endothelial cell proliferation through gene expression profiling
Authors: Hardwick James S. , Yang Yi , Zhang Chunsheng , Shi Bin , McFall Rosemary , Koury Elizabeth J. , Hill Susan L. , Dai Hongyue , Wasserman Robert , Phillips Robert L. , Weinstein Edward J. , Kohl Nancy E. , Severino Michael E. , Lamb John R. , Sepp-Lorenzino Laura
Published: February 2021

Extensive efforts are under way to identify antiangiogenic therapies for the treatment of human cancers. Many proposed therapeutics target vascular endothelial growth factor (VEGF) or the kinase insert domain receptor (KDR/VEGF receptor-2/FLK-1), the mitogenic VEGF receptor tyrosine kinase expressed by endothelial cells. Inhibition of KDR catalytic activity blocks tumor neoangiogenesis, reduces vascular permeability, and, in animal models, inhibits tumor growth and metastasis. Using a gene expression profiling strategy in rat tumor models, we identified a set of six genes that are selectively overexpressed in tumor endothelial cells relative to tumor cells and whose pattern of expression correlates with the rate of tumor endothelial cell proliferation. In addition to being potential targets for antiangiogenesis tumor therapy, the expression patterns of these genes or their protein products may aid the development of pharmacodynamic assays for small molecule inhibitors of the KDR kinase in human tumors.
Mystery Checkpoint Revealed: KIR3DL3 Finally Found a Ligand in HHLA2
Authors: Campbell Kerry S.
Published: February 2021

Inhibitory killer cell immunoglobulin–like receptors (iKIR) tolerize natural killer cells and some T cells upon detecting classical HLA class I molecules. In this issue, Bhatt and colleagues identify the B7 family member HHLA2 as an unanticipated ligand for a peculiar iKIR family member, KIR3DL3. These data establish a new inhibitory checkpoint pathway that may protect HHLA2+ tumor cells from immune attack.

See article by Bhatt et al., p. 156