bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relating vegetation condition to grazing management systems in the central Keiskamma Catchment, Eastern Cape Province, South Africa
Authors: Kakembo Vincent , Ndou Naledzani 
Published: February 2019

AbstractVegetation degradation has been identified as a serious environmental problem, around the communal villages of South Africa. An investigation of the relationship between vegetation condition and local grazing management systems was undertaken across the communal villages of the central Keiskamma Catchment, Eastern Cape Province. The hypothesis that “differences in grazing management strategies may explain the variations in vegetation condition within these communal villages” was tested. Landsat TM imagery of 1984 and 1999, in conjunction with SPOT‐4 imagery of 2011, was used to assess the spatial and temporal trends in vegetation. Structured interviews were administered among communal village authorities to obtain information regarding the functionality of local grazing management structures. Using the logistic regression in IDRISI Selva remote sensing software, relationships between vegetation condition and grazing management systems were analysed.Spatial and temporal trends in vegetation cover revealed a drastic reduction in fair vegetation, an increase in extremely degraded vegetation and bare/eroded surfaces, particularly in villages with ineffective rangeland management practices. The hypothesis was accepted; a distinct relationship between the respective grazing practices and vegetation condition was identified. Variations in the functionality of local grazing management structures in the communal villages account for the vegetation condition disparities observed. A revitalisation of these structures is key in vegetation restoration endeavours.
A wideband and low‐profile transmitarray antenna using different types of unit‐cells
Authors: Yang Xianhang , Zhou Yonggang , Xing Lei , Zhao Yongjiu 
Published: February 2019

AbstractA wideband low‐profile transmitarray antenna has been designed. Several prototypes of unit‐cells with different transmission phase shift ranges are used to constitute the antenna. To achieve wideband performance, the transmission phase versus frequency curves of these unit‐cell prototypes are required to be nearly parallel in the working frequency band. Also, two or more unit‐cell prototypes instead of a uniform prototype are used to avoid introducing air gaps and reduce the thickness of transmitarray, which is commonly used in transmitarray design. A wideband millimeter wave dual‐polarized transmitarray with a thickness of only 0.12λ0 is designed, fabricated, and measured. It is demonstrated that the antenna has a wide 1‐dB gain bandwidth of 20.2% (31‐38 GHz), a gain higher than 31.4 dBi, and a peak aperture efficiency of 41.3%. Good agreement between simulations and measurement is achieved.
A size reduced Gysel power divider with simple structure and high design flexibility
Authors: Liu Fu‐Xing , Wang Yang , Lee Jong‐Chul 
Published: February 2019

AbstractIn this letter, a new simple structure of Gysel power divider (PD) is proposed. Comparing to the conventional Gysel PD, the high‐power handling capability is reserved with size reduction from the nonlinear relationship between the phase delay and the physical dimension of the utilized open‐circuited coupled line. The structure is analyzed according to an open‐end‐stub‐based equivalent circuit, in which procedure the closed‐form design equations are derived simultaneously. Also, the analysis shows a high design freedom in choosing the values of the isolation resistors and the impedances of the utilized transmission lines (TLs), which property can be used to control the bandwidth (isolation and input return loss band) of the proposed structure. Finally, in order to verify the proposed design theory, a Gysel PD with a center frequency of 2.5 GHz is designed, simulated, fabricated, and characterized. Besides good agreement with the simulation data, the experimental results show that the proposed PD features a wide isolation band which is around 89% with the reference of 15‐dB loss.
A 1‐W Ka‐band power amplifier using 0.15‐μm InGaAs/GaAs E‐mode pHEMT technology
Authors: Lee Hui Dong , Park Jeongsoo , Kong Sunwoo , Kim Kwang‐Seon , Lee Kwang Chun , Park Bonghyuk , Kim Jeong‐Geun 
Published: February 2019

AbstractThis article presents a 1‐W Ka‐band power amplifier using 0.15‐μm InGaAs/GaAs enhancement‐mode pHEMT technology. We have introduced a method to obtain the required output power through the characteristics of the unit transistor provided by the manufacturer. At first, the PA circuit is designed to effectively combine the output signals of eight unit transistors. From the measurement results, 28.5 dBm output was obtained at 28 GHz and the maximum efficiency was reached to 25%. In order to achieve 1‐W output power, two power amplifiers were connected in parallel using T‐junction line combiner. Finally, an output power of 30.1 dBm was obtained. At the same time, the PA efficiency is 14.1%. As a result of linearity verification, we confirmed that this power amplifier has the ACLR characteristics of less than −30 dBc up to 23.3 dBm output.
In vitro genotoxic effects of titanium dioxide nanoparticles (n‐TiO2) in human sperm cells
Authors: Santonastaso Marianna , Mottola Filomena , Colacurci Nicola , Iovine Concetta , Pacifico Severina , Cammarota Marcella , Cesaroni Fulvio , Rocco Lucia 
Published: February 2019

AbstractTitanium dioxide nanoparticles (TiO2‐NPs) are one of the most widely engineered nanoparticles used. The study has been focused on TiO
2‐NPs genotoxic effects on human spermatozoa in vitro. TiO
2‐NPs are able to cross the blood–testis barrier induced inflammation, cytotoxicity, and gene expression changes that lead to impairment of the male reproductive system. This study presents new data about DNA damage in human sperms exposed in vitro to two n‐TiO
2 concentrations (1 µg/L and 10 µg/L) for different times and the putative role of reactive oxygen species (ROS) as mediators of n‐TiO
2 genotoxicity. Primary n‐TiO
2 characterization was performed by transmission electron microscopy. The dispersed state of the n‐TiO
2 in media was spectrophotometrically determined at 0, 24, 48, and 72 hr from the initial exposure. The genotoxicity has been highlighted by different experimental approaches (comet assay, terminal deoxynucleotidyl transferase dUTP nick end labeling [TUNEL] test, DCF assay, random amplification of polymorphic DNA polymerase chain reaction [RAPD‐PCR]). The comet assay showed a statistically significant loss of sperm DNA integrity after 30 min of exposure. Increased threshold of sperm DNA fragmentation was highlighted after 30 min of exposure by the TUNEL Test. Also, the RAPD‐PCR analysis showed a variation in the polymorphic profiles of the sperm DNA exposed to n‐TiO
2. The evidence from the DCF assay showed a statistically significant increase in intracellular ROS linked to n‐TiO
2 exposure. This research provides the evaluation of n‐TiO
2 potential genotoxicity on human sperm that probably occurs through the production of intracellular ROS.
Aortic 4D flow MRI in 2 minutes using compressed sensing, respiratory controlled adaptive k‐space reordering, and inline reconstruction
Authors: Ma Liliana E. , Markl Michael , Chow Kelvin , Huh Hyungkyu , Forman Christoph , Vali Alireza , Greiser Andreas , Carr James , Schnell Susanne , Barker Alex J. , Jin Ning 
Published: February 2019

PurposeTo evaluate the accuracy and feasibility of a free‐breathing 4D flow technique using compressed sensing (CS), where 4D flow imaging of the thoracic aorta is performed in 2 min with inline image reconstruction on the MRI scanner in less than 5 min.MethodsThe 10 in vitro 4D flow MRI scans were performed with different acceleration rates on a pulsatile flow phantom (9 CS acceleration factors [R = 5.4–14.1], 1 generalized autocalibrating partially parallel acquisition [GRAPPA] R = 2). Based on in vitro results, CS‐accelerated 4D flow of the thoracic aorta was acquired in 20 healthy volunteers (38.3 ± 15.2 years old) and 11 patients with aortic disease (61.3 ± 15.1 years) with R = 7.7. A conventional 4D flow scan was acquired with matched spatial coverage and temporal resolution.ResultsCS depicted similar hemodynamics to conventional 4D flow in vitro, and in vivo, with >70% reduction in scan time (volunteers: 1:52 ± 0:25 versus 7:25 ± 2:35 min). Net flow values were within 3.5% in healthy volunteers, and voxel‐by‐voxel comparison demonstrated good agreement. CS significantly underestimated peak velocities (vmax) and peak flow (Qmax) in both volunteers and patients (volunteers: vmax, −16.2% to −9.4%, Qmax: −11.6% to −2.9%, patients: vmax, −11.2% to −4.0%; Qmax, −10.2% to −5.8%).ConclusionAortic 4D flow with CS is feasible in a two minute scan with less than 5 min for inline reconstruction. While net flow agreement was excellent, CS with R = 7.7 produced underestimation of Qmax and vmax; however, these were generally within 13% of conventional 4D flow‐derived values. This approach allows 4D flow to be feasible in clinical practice for comprehensive assessment of hemodynamics.
DeepCEST: 9.4 T Chemical exchange saturation transfer MRI contrast predicted from 3 T data – a proof of concept study
Authors: Zaiss Moritz , Deshmane Anagha , Schuppert Mark , Herz Kai , Glang Felix , Ehses Philipp , Lindig Tobias , Bender Benjamin , Ernemann Ulrike , Scheffler Klaus 
Published: February 2019

PurposeTo determine the feasibility of employing the prior knowledge of well‐separated chemical exchange saturation transfer (CEST) signals in the 9.4 T Z‐spectrum to separate overlapping CEST signals acquired at 3 T, using a deep learning approach trained with 3 T and 9.4 T CEST spectral data from brains of the same subjects.MethodsHighly spectrally resolved Z‐spectra from the same volunteer were acquired by 3D‐snapshot CEST MRI at 3 T and 9.4 T at low saturation power of B1 = 0.6 µT. The volume‐registered 3 T Z‐spectra‐stack was then used as input data for a three layer deep neural network with the volume‐registered 9.4 T fitted parameter stack as target data.ResultsAn optimized neural net architecture could be found and verified in healthy volunteers. The gray‐/white‐matter contrast of the different CEST effects was predicted with only small deviations (Pearson R = 0.89). The 9.4 T prediction was less noisy compared to the directly measured CEST maps, although at the cost of slightly lower tissue contrast. Application to an unseen tumor patient measured at 3 T and 9.4 T revealed that tumorous tissue Z‐spectra and corresponding hyper‐/hypointensities of different CEST effects can also be predicted (Pearson R = 0.84).ConclusionThe 9.4 T CEST signals acquired at low saturation power can be accurately estimated from CEST imaging at 3 T using a neural network trained with coregistered 3 T and 9.4 T data of healthy subjects. The deepCEST approach generalizes to Z‐spectra of tumor areas and might indicate whether additional ultrahigh‐field (UHF) scans will be beneficial.
Passage Effectiveness at a Pool-and-Weir Fishway Designed to Accommodate Pacific Lampreys
Authors: Ackerman Nicklaus K. , Pyper Brian J. , David Margaret M. , Wyatt Garth J. , Cramer Dan P. , Shibahara Timothy M. 
Published: February 2019

Abstract
Providing passage at man-made barriers is important to preserving migratory fish species. Fishways used to bypass barriers have historically been designed to provide passage for economically important species, with little regard given to nontarget species. Consequently, native fish species whose swimming behaviors are not well suited to these fishways have suffered from restricted access to habitat. For example, poor passage at dams has contributed to declines in populations of Pacific Lamprey Entosphenus tridentatus in the Columbia River basin. Pool-and-weir fishways typical of Columbia basin dams are well suited to salmonids but not to anguilliforms like the Pacific Lamprey. We evaluated the passage efficiency of Pacific Lampreys through a new pool-and-weir fishway at River Mill Dam on the Clackamas River, Oregon, that was designed to facilitate Pacific Lamprey passage. Rounded corners at the fishway entrances, flush-mounted weir gates, chamfered corners on orifices and weir walls, and orifices flush with the floor were all included in the fishway design specifically for Pacific Lampreys. In 2013 and 2015, Pacific Lampreys were radio-tagged and PIT-tagged to assess passage success. Dam passage efficiency estimates ranged from 84% to 98%, roughly 10–50% higher than Pacific Lamprey passage efficiency estimates at other dams in the Pacific Northwest. The median passage time through the fishway was 0.87 d in 2013 and 0.71 d in 2015. The high passage efficiency of Pacific Lampreys at River Mill Dam is likely due to the design elements incorporated specifically for Pacific Lampreys. These features could inform future fishway designs and modifications at locations where Pacific Lamprey passage is a consideration.
Do appreciable changes in the upper extremity motor capability to perform clean intermittent catheterization come about with time after traumatic spinal cord injury?
Authors: Elliott Christopher S. , Zlatev Dimitar , Crew James , Shem Kazuko 
Published: February 2019

AbstractIntroductionBladder dysfunction after spinal cord injury (SCI) often requires clean intermittent catheterization (CIC) or other management strategies. A common dilemma in those desiring to perform CIC independently but lacking the appropriate upper extremity (UE) motor function is the timing of reconstructive surgery.MethodsWe assessed the National Spinal Cord Injury Data Set for the years 2000‐2016. Our cohort consisted of persons with cervical SCI, who underwent complete motor examination upon discharge from rehabilitation and at 1‐year follow‐up. Using a previously published algorithm, UE motor scores were transformed to predict a patient's ability to independently perform CIC. Improvements in the predicted ability to self‐catheterize were evaluated.ResultsOf the 1428 individuals meeting the inclusion criteria, improvements in the predicted UE motor function necessary to independently self‐catheterize were observed in 39%, 42%, and 38% of those deemed possibly able, only able with surgical assistance, or unable to self‐catheterize at rehabilitation discharge, respectively. On multivariate analysis, only increasing Association Impairment Scale (AIS) classification and AIS classification improvement over the first year were associated with an increased odds of improving predicted CIC ability (odds ratio [OR] = 1.44 for AIS C and 1.97 for AIS D compared with AIS A, and OR = 1.90 for AIS classification improvement versus stable AIS classification, P < 0.05 for each).ConclusionImprovements in UE motor function to independently perform CIC occur in approximately 40% of persons with cervical SCI in the first year after rehabilitation discharge. Those with incomplete injuries are more likely to improve. These findings should enhance patient bladder management counseling and guide surgeons in determining an appropriate timeline for offering reconstruction.
Full‐waveform inversion of complex resistivity IP spectra: Sensitivity analysis and inversion tests using local and global optimization strategies on synthetic datasets
Authors: Vinciguerra Alessandro , Aleardi Mattia , Costantini Paolo 
Published: February 2019

ABSTRACTWe implement two different inversion strategies for solving the full‐waveform inversion of spectral induced polarization data: the first is a local inversion based on the Levenberg–Marquardt algorithm, whereas the second is a global optimization that makes use of the Particle Swarm Optimization algorithm. In addition, the analysis of the residual function maps and the singular value decomposition of the inversion kernel are used to analyse the complexity of the objective function and the ill‐posedness of this inverse problem. We limit the attention to synthetic data with the aim to maintain the inversion at a simple level and to draw essential conclusions about the ill‐conditioning of the considered inverse problem and about the suitability of the two inversion approaches we use. We consider two differexnt double‐dispersion reference models that generate resistivity amplitude and phase spectra with different characteristics. Realistic noise is added to the synthetic data to better simulate a field data set. We also apply a dedicated processing sequence to increase the signal‐to‐noise ratio of the observed data. It turns out that the full‐waveform inversion of spectral induced polarization is a well‐posed problem in case of double‐peaked resistivity spectra, whereas it becomes hopelessly ill‐conditioned when the subsurface model generates single‐peaked spectra. In particular, the analysis of the residual function maps demonstrates that in case of double‐peaked spectra the objective function is characterized by a well‐defined single minimum. Conversely, elongated valleys with similar misfit values arise for single‐peaked spectra. In this case, the eigenvectors in model space demonstrate that the estimate of the τ1 and c1 parameters is a non‐unique problem, and for this reason it would be advisable to reparametrize the inverse problem by considering a single‐dispersion model. In addition, our tests demonstrated the superior exploitation capability of the linearized inversion with respect to the global optimization, that is the ability to converge towards the minimum in case of objective functions with low gradient values.
Professional networks and support for nursing home directors of nursing
Authors: Rao Aditi D. , Evans Lois K. , Mueller Christine A. , Lake Eileen T. 
Published: February 2019

ABSTRACTIn this study, we examined the influence of professional network characteristics, available professional support, and perceived support quality on intent to stay among for‐profit nursing home (NH) directors of nursing (DON). We hypothesized that the receipt of high quality professional support would be associated with DON intent to stay. DONs have a critical mandate to provide leadership that influences their facilities’ work climate and care quality. Yet, they often struggle to manage overwhelming responsibilities and are left feeling alienated, frustrated, and intent on leaving their jobs. Professional support, accessed via professional networks, may help DONs combat frustration and mitigate turnover that threatens NH care quality. Using a descriptive survey design, we electronically surveyed all DONs employed by a single for‐profit NH corporation to collect data pertaining to their professional networks, receipt of professional support, perceptions regarding support quality, and intentions to stay in their positions. One‐hundred‐ninety‐five DONs (65%) responded, with 133 (44%) completing every survey component. We employed social network analysis methods to construct datasets linking descriptors of DON respondents with attribute information about 1,164 network members. Statistical analyses (ANOVAs, point biserial correlations, and binomial logistic regression) yielded several findings supporting our hypothesis: (i) DONs’ professional networks closely resembled the teams in which they worked daily; (ii) DONs relied on this core network of individuals to provide task support primarily; (iii) DON‐nursing home administrator relationships were most important; and (iv) perceptions of support quality and support from nursing home administrators were the strongest predictors of DON intent to stay.
Entheseal changes in ancient Egyptians from the pyramid builders of Giza—Old Kingdom
Authors: Refai Osama 
Published: February 2019

AbstractEntheseal changes are distinct skeletal markings that occur where a muscle, tendon, or ligament inserts into bone cortex, in response to many factors including physical activity. Therefore, entheseal changes have been frequently used to reconstruct habitual life activities of ancient populations. The present study examines a sample of 195 ancient Egyptians from Giza—Old Kingdom (2700–2190 BC), the period of pyramid builders. The material consists of two burials that were identified as belonging to individuals of different socio‐economic classes: workers and high officials. This distinction between the socio‐economic classes is based on evidence including location and design of cemeteries, contents of goods, and writings and drawings on tombs. Entheseal changes at 14 sites, representing the main articulations of the body, were examined to assess any association between entheseal expression and physical activities. The results of this study suggest that the frequency and severity of entheseal changes varied between workers and high officials, and between males and females. As expected, males exhibited higher levels of entheseal expression, suggesting sexual dimorphism in activity. No clear bilateral asymmetry was observed, except for in female high officials, who exhibited higher levels of entheseal expression at the right hand. A direct comparison of frequencies of entheseal changes between the two social classes, by sex and age, revealed that male and female workers had higher levels of entheseal expression than high officials, suggesting a division in labour. Together, these data suggest that entheseal changes can be used, cautiously, to study activity patterns in ancient Egyptian populations.
Shorter Height is Associated with Diabetes in Women but not in Men: Nationally Representative Evidence from Namibia
Authors: Koncz Viola , Geldsetzer Pascal , Manne‐Goehler Jennifer , Wendt Amanda S. , Teufel Felix , Subramanian S.V. , Bärnighausen Till , De Neve Jan‐Walter 
Published: February 2019

ObjectiveThis study aimed to test the hypothesis that attained adult height, as an indicator of childhood nutrition, is associated with diabetes in adulthood in Namibia, a country where stunting is highly prevalent.MethodsData from 1,898 women and 1,343 men aged 35 to 64 years included in the Namibia Demographic and Health Survey in 2013 were analyzed. Multiple logistic regression models were used to calculate odds ratios (ORs) and 95% CIs of having diabetes in relation to height. The following three models were considered: Model 1 included only height, Model 2 included height as well as demographic and socioeconomic variables, and Model 3 included body mass index in addition to the covariates from Model 2.ResultsOverall crude diabetes prevalence was 6.1% (95% CI: 5.0‐7.2). Being taller was inversely related with diabetes in women but not in men. In Model 3, a 1‐cm increase in women’s height was associated with 4% lower odds of having diabetes (OR, 0.96; 95% CI: 0.94‐0.99; P = 0.023).ConclusionsHeight is associated with a large reduction in diabetes in women but not in men in Namibia. Interventions that allow women to reach their full growth potential may help prevent the growing diabetes burden in the region.