bluuebunny/crossref_metadata_2025 huggingface dataset:
Design of high precision AC current power supply based on STM32F407
Authors: Chen Kailun , Luo Zhaotong , Wang Zikun , Chen Qiong
Published: September 2019

The design and implementation of high precision and stable AC current supply plays an important role in the use of various electronic devices. In order to achieve the design requirements of high output accuracy, good stability and low uncertainty, STM32F407 Microcontroller Unit is used as the control core in hardware, high-precision current is generated through digital-analog conversion circuit, and closed-loop adjustment control system is realized with I/V conversion and sampling circuit. Based on the fast Fourier transform theory, the device adopts the technology of surface-source integration and uses liquid crystal display configuration screen as the human-computer interaction medium. The experimental results show that its accuracy can reach 5/10,000, its stability can reach 5/100,000, and its uncertainty can reach 1/1,000. It is suitable for various high-precision occasions.
The evaluation of performance cost for network based moving target defense
Authors: Xiong Xinli , Li Kechang , Zhao Guangsheng
Published: September 2019

Network based moving target defense prevents attackers from reliably contacting a system by re-configuring network factors. Although limited researching has demonstrated it to be practical and feasible, little studies have been conducted to evaluate the performance cost appended to the original system. Without quantitative results, it is challenging to implement moving target techniques to typical information system broadly. This paper introduces a Queueing Petri Net model that can provide insight into the performance of network re-configurations. This model quantifies the system throughput, queue utilization and response time of requests regarding configurations of the information system, type of strategies for mutation and the frequency of networking transformation. Through logical deductions and simulations using Queueing Petri net Modelling Environment, results show that the network shifting method is an affordable defense technology compared to the performance loss in the processing of servers. Moreover, event-based strategies can get the trade-off between security and performance. These results guide the research deep into developing a more optimized method in moving target defense.
A broadband low noise amplifier in 70nm GaAs MHEMT process
Authors: Guan Jin , Gong Min , Gao Bo , Lu Yuxi
Published: September 2019

In this paper, a broadband low noise amplifier (LNA) is presented with 70nm GaAs metamorphic high electron mobility transistor (MHEMT) process. The feedback and input/output impedance match techniques for broadband amplifier are presented. The stability, noise figure, gain flatness, and S-parameter performance of this LNA are analyzed and discussed. The small signal gain of the LNA is 20dB±0.2dB and noise figure of 0.86dB~1.35dB among operating from almost DC to 15GHz. This LNA exhibits reflection below -10dB, power dissipation of 70mW and chip area of 1.0mm*0.6mm. This LNA finds its application in many wideband systems.
Multiple target recognition of UAV based on image processing
Authors: Deng Weidong , Tang Daquan , Lu Keke , Tang Guanzheng
Published: September 2019

Unmanned aerial vehicle (UAV) has been widely used in military and civil fields due to its unique advantages. Aiming at the principle of UAV in reconnaissance field and target recognition field, a method of UAV multi-target recognition based on image processing is proposed, and the validity of the method is verified by building an UAV platform and field experiments. At the same time, the display interface of image processing results is developed, which can get the UAV recognition results in real time. Finally, the experimental results are analyzed, and the factors affecting the accuracy of UAV target recognition are elaborated.
The analysis of type-2 fuzzy controller for ITER PF ac/dc converter control system
Authors: Ul Hassan Mahmood , Humayun Muhammad , Huang Liangsheng , Waheed Bushra , Fu Peng , Song Zhiquan
Published: September 2019

This novel type 2 fuzzy controller (T2FC) have more attractive research to developed the membership functions (MF) and rule uncertainties in the complex tokamak International Thermonuclear Experimental Reactor (ITER) Poloidal Field (PF) system. The uncertainties always happened to design the MF in real time applications. This paper proposes the T2FC design strategy in single and parallel operation. During the operations it is inflexible to handle the extremely uncertain and cannot determine the membership grades by conventional type 1 fuzzy controller (T1FC). To address the uncertainties issues the T2FC is the robust technique to accommodate the rule and membership uncertainties.
Research on MCGS biochar measurement and control system
Authors: Zhu Kai , Wang Zixin , Zhang Zhixia
Published: September 2019

Biochar is a kind of carbon-rich, highly aromatic and highly stable solid product produced by high temperature thermal cracking of biomass feedstock under complete anaerobic or partial anoxic conditions. It is pyrolyzed at 300~500 °C. Biochar can be prepared from rice straw. Based on the actual needs, this paper proposes a biochar carbonization temperature control technology based on the Internet of Things technology for straw carbonization. The SCADA data monitoring and control system consists of a Modbus-based, Web Access web database and a remote data transmission and local control network. With ADAM-4060 and intermediate relay as the control core, thermocouple, ADAM-4018 data acquisition module, MCGS industrial grade programmable human-machine interface and no Web Access webpage database, remote monitoring of carbonization furnace temperature parameters, and according to the alarm status and warning line alert the manager to control the operation of the blower. The purpose of this paper is to find the optimum carbonization temperature for rice and to control the internal temperature of the carbonization furnace near the optimum temperature.
Exploring possibility to improve frequency properties of 1200V and 1700V IGBT and FRD with partially diffused proton beam
Authors: Surma Alexey Maratovich , Verevkin Vladimir Viktorovich , Volobuev Kirill Andrianovich
Published: September 2019

Authors research a technology to improve frequency properties of IGBT and FRD using a partially diffused high-energy proton beam, and demonstrate a possibility to use this technology to manufacture fast and ultrafast IGBT and FRD for frequencies within 20-50 kHz.
Study on straightness measurement technology of slender rod based on time-domain three-point method
Authors: Chen Xinchun , Bi Mengxue , Xue Chunyang
Published: September 2019

Straightness is the key geometric accuracy index of the slender rod of key parts of large machinery, which directly affects the manufacturing and installation accuracy, working efficiency and service life of mechanical products. In order to improve the manufacturing precision of the slender rod and overcome the limitations of the existing methods, a method for measuring the straightness of the slender rod based on the time-domain three-point method is proposed. According to the structural characteristics of the slender rod, the measurement principle and the overall scheme of the measurement system are given, and the mathematical model of the straightness measurement is established. Taking the core components of a construction machine as an example, the measurement and comparison of the designed measuring device and the laser tracker are used to prove that the measurement error of the designed measuring device is less than 0.005 mm. The measurement system analysis results show that the R&R of the designed measuring device has less than 10% of the research variation, indicating that its repeatability and reproducibility are good, which further proves that it can be applied to the actual production site.
Research on process task scheduling method for complex equipment manufacturing based on genetic algorithm
Authors: Wang Yujie , Huang Song , Cao Xiang , Qin Xiaopin
Published: September 2019

The research and application of effective scheduling methods play an important role in manufacturing enterprises to improve production efficiency and reduce production costs. Based on the characteristics of the capability maturity of processors, this paper establishes a process task scheduling strategy that is conducive to guarantee delivery time and reduce labor costs according to the actual production environment of complex equipment manufacturing enterprises. A scheduling two-level planning model with delay time and labor cost as indicators is constructed, and the model is solved by genetic algorithm. The planning scheduling method based on order priority and technician effective working time constraints is studied. Finally, an example is given to verify the feasibility and effectiveness of the proposed method.
Numerical simulation of NC spinning manufacturing on tantalum tungsten alloy cylinder part
Authors: Li Xueguang , Zhang Zhifeng , Liang Wei , Miao Liqin
Published: September 2019

The tantalum tungsten alloy has excellent mechanical properties which is used extensively in many fields, in this paper, the spinning manufacturing simulation model was built for the tantalum tungsten alloy cylinder part based on finite element method, the spinning process parameters were designed according to the actual working conditions, the stress, strain and the materials flowing behavior during the spinning process were analyzed, the spinning manufacturing results was obtained. Then the influence of spinning wheel working angle, spinning wheel fillet radius, spinning feed rate and thinning rate on equivalent strain was discussed.
Study on process and manufacturability of metal-bonded diamond grinding wheel fabricated by selective laser melting (SLM)
Authors: Tian Chenchen , Li Xuekun , Li Hanyang , Guo Guoqiang , Wang Liping , Rong Yiming
Published: September 2019

Selective laser melting (SLM) technology is used to fabricate metal-bonded grinding wheel based on mixed powders consisted of metal powders and diamond abrasives. Taguchi method is adopted to obtain the optimal SLM process parameters for grinding wheel considering laser power, scanning speed and layer thickness. Specimens are fabricated with different SLM process parameters for compression and three-point bending tests. Materials characterization and manufacturing limit test are performed on the specimens fabricated by the optimal SLM process. Results indicate that laser power of 250W, scanning speed of 2.5m/s and layer thickness of 20μm are determined as the optimal SLM process in terms of comprehensive mechanical property and formed surface quality. Moreover, diamond abrasives are firmly embedded into aluminium binder with good bonding condition for SLM-fabricated composite. Furthermore, manufacturability of SLM-fabricated composite is evaluated by manufacturing limits of several common structures. In summary, work in this study fully proves the feasibility of SLM-fabricated metal-bonded grinding wheel and provides a solid basis for the further investigation on the novel grinding wheel with customized porous structures.
Analysis of bending vibration characteristics of rotating composite boring bar
Authors: Ren Yongsheng , Zhao Qi , Liu Yinlei , Ma Jingmin
Published: September 2019

In this study, the dynamic characteristics of composite boring bar are theoretically investigated. The structural dynamic model of composite boring bar having clamped-free supports is developed by employing Bernoulli-Euler beam theory and considering dissipative characteristics of viscoelastic composite material. The Galerkin method is used to solve the equations of bending vibration. The complex characteristic equation for bending vibration is derived. Numerical examples present the variation of the natural frequency, damping and dynamic stiffness with ply angle, and the variation of the natural frequency and damping with rotating speed are also obtained. The study results show that ply angle, stacking sequences and ratio of length over outer radius have significant influence on the dynamic characteristics of composite boring bar. Conclusively, lamination design can significantly improve dynamic performance and enhance chatter stability in machining.
Precision assembly method based on coaxial alignment and force control
Authors: Guo Pengyue , Zhang Zhijing , Liu Yan , Sun Weichen , Li Zhe
Published: September 2019

To ensure the assembly performance of precision assembly system, a high-precision assembly system for gear-piece and gear-shaft is developed in this paper, which consists of a computer, two manipulators, a coaxial alignment module(CAM), a selective compliance assembly robot arm (SCARA), an adjusting platform and a force sensor. The CAM is used to calculate the position and angular deviation of gear-piece and gear-shaft. The force sensor is equipped to detect the contact force. In the stage of adjusting alignment, position-based visual servoing (PBVS) is adopted to ensure high precision alignment of parts. In the insertion stage, an impedance control method based on position is proposed to ensure the contact force. Experiments are carried out to demonstrate the validation of the proposed system and methods. Automated assembly of parts with a 5μm gap is achieved.
Sustainable Development approaches in Egypt
Authors: Abdelrahman Hussein Ahmed Adel , Pollock Eric
Published: September 2019

In conjunction with the current Egyptian sustainable and economic reform plan to enrich the country resources and face future challenges, the megaprojects have been pursued to improve the infrastructure and encourage investment. Starting with renewable energy planets and passing by 14 new sustainable cities all over Egypt to absorb the future expected population and improve the living standards of the Egyptian citizens. One of those cities is the New Administrative Capital which is being built as a smart city on an uninhabited strategic area between the Suez Canal and the Nile River and it will become the new administrative and financial capital of Egypt, housing the main government departments and ministries, as well as foreign embassies. This paper attempts to review the United Nations Sustainable Development Goals in the Egyptian megaprojects with a special focus for the Egyptian New Administrative Capital city.
Towards more sustainable patterns of urban development
Authors: Marino F P R , Lembo F , Fanuele V
Published: September 2019

DETR, 1998, wrote in Planning for Sustainable Development. Towards Better Practice: “New settlements will enjoy a high quality of urban and landscape design. As well as integrated open space, there should be habitat areas, and environmental gains such as energy efficiency measures introduced in layouts and individual buildings”; but this claim is remained largely dissatisfied. There is a great interest (and large investments in research) for the smart city, which seeks to optimize the existing cities, while people go on to design urban developments with building typologies set ninety years ago by Modern Movement or little more. Urban Planning compares existing cities’ models and asseverates that densification has positive role for sustainability, but do not turns enough to account passive typologies for heating and cooling, which can turn down near to zero power-consumption, and at the same time can raise urban environment quality. Famous settlements too, as Malmö or Vauban in Freiburg, has been built with building typologies conventional, after all; German passive Haus have generally two, three or four building fronts and in reality, are simply hyper-insulated traditional buildings, furnished with mechanical controlled ventilation. For an urban extension of Potenza, we have used for the urban planning the sustainability assessment categories of ITACA’s Protocol, derivative from GBTool of GBC, people normally use to assess ex-post sustainability of projects and of realized buildings. The result is a settlement in which pedestrian, cycle and public transport’s network is fully integrated with adjacent urban areas; effective landscaping connects public and private green and kitchen-gardens/orchards are everywhere; buildings are made with new semi-underground typologies, nZEB and made with local, re-cyclable materials; rain water is collected, in-loco fito-depurated and reused; in-loco renewable energies (sun, earth, wind) satisfies remaining necessities.
Residential movements in connection to renovation of rented multi-residential housing: A pilot study
Authors: Femenías P , Jonsdotter L , Forsemalm J , Punzi E , Bogdanova E , Thodelius C , Granath K
Published: September 2019

Residential movement and displacement as an effect of renovation has earned attention and also affected renovation practices in Sweden. While statistical studies have linked deep renovation to residential movement and displacement, there are no recent studies that investigate why people move or remain in housing areas that are renovated, and if and how the relocation is determined by the renovation. A pilot study was initiated as a means to develop a methodology to study residential movement in connection to renovation. In this paper, methodological considerations are discussed based on 31 interviews (face-to-face and telephone) with movers related to 34 municipally owned rented housing areas about to undergo renovation, as well results from a questionnaire sent to two finalised renovation projects (N=113). So far, the pilot study indicate that few relocations can be linked to the up-coming or finalised renovation in the studies cases. The questionnaire that was sent out to remaining tenants had a low response rate of 29%, and the efficiency of using questionnaires is discussed.
Simulation of snow cover formation and melt with publication of the output data on the web map service (on the example of Kama river basin)
Authors: Pyankov S V , Kalinin N A , Shikhov A N , Abdullin R K , Bykov A V
Published: September 2019

It is performed an assessment of the use of daily precipitation forecasts of global numerical weather prediction (NWP) models GFS (U.S.), GEM (Canada), SLAV (Russia) and ICON (Germany) as input data for snow accumulation and melt modelling in the Kama river basin for two cold seasons. It is shown, that maximum snow water equivalent (SWE) calculated on the basis of NWP models output has an error less than 27% of the measured values, in the conditions of 2017-2018 snow accumulation season. However, this is preliminary assessment, which requires verification by several seasons. It is rather difficult to conclude which model provides highest accuracy of SWE calculation, because each of them has its specific limitations. In 2018-2019 cold season, we additionally obtained ICON model data, which provides the most accurate forecast of precipitation. The simulated SWE and meltwater outflow data are published on the online web map service.
The role of precipitation and air temperature in the formation of summer runoff
Authors: Akmatov R T , Alamanov S K , Choduraev T M
Published: September 2019

This article focuses on the analysis of the formation of river flow in the summer period, in which there is the greatest need for water to meet agricultural needs and there is the maximum contribution of glacier water to the total flow. To identify the influence of air temperature and precipitation in different summer months and in general for June-August, calculated were correlation coefficients between climate elements and the water content of watercourses. The steady dependence of the runoff on air temperature, both for individual months and the summer period, is generally characteristic only of the Chon and Kichi Naryn river basins.
Formation of bottom sediments in valley reservoirs and its research methods
Authors: Koviazina I A , Kalinin V G
Published: September 2019

The paper presents a review of studies by Russian and foreign scientists on the formation of bottom sediments in valley reservoirs. The typing of the main factors according to the time of occurrence and the source of income was carried out. Methods for studying the processes of bottom sediments formation are identified. This is an assessment of the material collapsed volume at coastal stations, the calculation of the solid flow in the main tributaries, sampling of bottom soil, repeated depth measurements. The organization of comprehensive studies of the input and expenditure components of the sedimentation balance and modelling of spatial and temporal changes in the bottom relief using GIS-technologies is important for predicting the siltation of reservoirs.
Analysis of the dependencies of spring flood runoff from the main factors
Authors: Kalinin V G , Mekhanoshina E V
Published: September 2019

The article is devoted to study of the conditions of the spring flood runoff formation in high water years. The authors analysed the dependences of the runoff layer on the main factors such as the maximum water storage in the snow before the beginning snowmelt, sum of the positive air temperatures, sum of the precipitation during the spring flood and autumn moistening. It was revealed that the determining factors in the formation of the spring flood runoff layer on the rivers of the Votkinsk catchment are the maximum water reserve in snow and precipitation that fell during this period.
Formation of the hydrochemical regime of Lake Zuratkul
Authors: Zakharov S G
Published: September 2019

The changes in the hydrochemical state of the water masses of the lake-reservoir Zyuratkul for the period 1966 - 2018 are considered. on the concentration of the main water ions, nitrogen and phosphorus compounds, oxidability, some hydrophysical parameters (transparency, chromaticity). Conclusions about cyclical and evolutionary change of individual parameters and characteristics of water masses are made. Defined modern water quality in the reservoir.
Long-term dynamics of hydrobiont communities in Kenon Lake
Authors: Bazarova B B , Kuklin A P , Matafonov P V , Tsybekmitova G Ts , Gorlacheva E P , Afonina E Yu , Tashlykova N A
Published: September 2019

Long-term researches of Kenon Lake, that exploited the lake as a cooling reservoir of the Chita thermoelectric plant-1, have revealed that composition of the dominating system of hydrobiont and fish communities of the lake has no significant variations. Maintenance of the lake level at the expense of pumping water from Ingoda River leads to flatness of processes taking place in the ecosystem and possibilities for the ecosystem state regulation.
Comparative characteristic of plankton microbial community in the waterway and coastal areas of the Kama reservoirs cascade
Authors: Tarasova N G , Bykova S V , Gorbunov M Yu , Krasnova E S , Umanskaya M V
Published: September 2019

The comparative analysis of indicators of development of various components of plankton community in reservoirs of the Kama cascade in various hydrological seasons, and on various sites (in coastal and waterway) was carried out. The difference in the quantitative development of unicellular pro- and eukaryotes in different areas (coastal and riverbed) was more pronounced than in different hydrological seasons (spring flood and summer low water). Cyanobacteria make the greatest contribution to the formation of the total biomass of phytoplankton in the waterway. The contribution of heterotrophic component (bacteria and ciliata) is more significant in the coastal area. It was shown the significant correlation of the biomass of unicellular plankton and picodetritus particles, which was present in considerable amounts in the waters of the Kama reservoirs cascade.
Conductivity and capacitance of streamers in avalanche model for streamer propagation in dielectric liquids
Authors: Madshaven I , Hestad OL , Unge M , Hjortstam O , Åstrand PO
Published: September 2019

Propagation of positive streamers in dielectric liquids, modeled by the electron avalanche mechanism, is simulated in a needle–plane gap. The streamer is modeled as an RC-circuit where the channel is a resistor and the extremities of the streamer have a capacitance towards the plane. The addition of the RC-model introduces a time constant to the propagation model. Increase in capacitance as a streamer branch propagates reduces its potential, while conduction through the streamer channel increases its potential, as a function of the time constant of the RC-system. Streamer branching also increases the capacitance and decreases the potential of the branches. If the electric field within the streamer channel exceeds a threshold, a breakdown occurs in the channel, and the potential of the streamer is equalized with the needle electrode. This is interpreted as a re-illumination. According to this model, a low conductive streamer branch can propagate some distance before its potential is reduced to below the propagation threshold, and then the RC time constant controls the streamer propagation speed. Channel breakdowns, or re-illuminations, are less frequent when the channels are conductive and more frequent for more branched streamers.
Oxytocin-induced prostaglandin F2-alpha release is low in early bovine pregnancy but increases during the second month of pregnancy†
Authors: Drum Jéssica N , Wiltbank Milo C , Monteiro Pedro L J , Prata Alexandre B , Gennari Rodrigo S , Gamarra Caio A , Canavessi Aurea M O , Sartori Roberto
Published: September 2019

Circulating prostaglandin F2α metabolite (PGFM) after an oxytocin challenge was evaluated throughout the first 2 months of pregnancy in lactating Holstein cows. On day 11, 18, and 25 after artificial insemination (AI), and on days 32, 39, 46, 53, and 60 of pregnancy, cows were challenged with 50 IU oxytocin, i.m. Blood was collected before (0 min), 30, 60, 90, and 120 min after oxytocin for plasma PGFM concentrations. Ultrasound evaluations were performed for pregnancy diagnosis on day 32–60 post-AI. Nonpregnant (NP) cows on day 18 were designated by a lack of interferon-stimulated genes in peripheral blood leukocytes and Pregnant (P) based on day 32 ultrasound. On day 11, P and NP were similar with low PGFM and no effect of oxytocin on PGFM. On day 18, oxytocin increased PGFM (3-fold) in NP with little change in P cows. Comparing only P cows from day 11 to 60, basal circulating PGFM increased as pregnancy progressed, with day 11 and 18, lower than all days from day 25 to 60 of pregnancy. Oxytocin-induced PGFM in P cows on day 25 was greater than P cows on day 18 (2.9-fold). However, oxytocin-induced PGFM was lower on day 25 compared to day 53 and 60, with intermediate values on day 32, 39, and 46 of pregnancy. Thus, the corpus luteum (CL) of early pregnancy (day 11, 18) is maintained by suppression of PGF, as reflected by suppressed PGFM in this study. However, during the second month of pregnancy, uterine PGF secretion was not suppressed since basal PGFM and oxytocin-induced PGFM secretion were elevated. Apparently, mechanisms other than suppression of oxytocin receptors maintain CL after day 25 of pregnancy.
Combination Lorcaserin and Nicotine Patch for Smoking Cessation Without Weight Gain
Authors: Rose Jed E , Davis James M
Published: August 2019

Introduction

This study explored the efficacy of combination lorcaserin and nicotine patch for smoking cessation treatment and prevention of postsmoking cessation weight gain.

Methods

We conducted a trial in which 61 adult daily smokers were asked to quit smoking using a combination of lorcaserin and nicotine patch. During the first 2 weeks of treatment prior to the quit day, participants were randomized to receive either lorcaserin (10 mg twice daily) plus nicotine patch (21 mg) or placebo plus nicotine patch (21 mg). Following this 2-week period, participants received both medications for 12 weeks. Outcomes included 4-week continuous smoking abstinence at the end of treatment (weeks 7–10 postquit attempt), weight change, ad libitum smoking, withdrawal symptoms, and ratings of cigarette reward.

Results

Biochemically confirmed continuous smoking abstinence from 7 to 10 weeks postquit attempt was 31.1% (90% confidence interval, 21.4%–40.8%). Participants who quit smoking showed no weight gain; in fact, mean weight change was minus 0.16 kg (SD = 3.27) over the study period. There was an unexpected but strong association (p = .006) between a decrease in sensory enjoyment of smoking and successful quit outcome on this regimen. During the prequit randomization period, lorcaserin versus placebo reduced the impact of smoking to relieve craving for cigarettes as well as the sensory enjoyment of smoking (p = .005). Adherence and tolerability to lorcaserin and nicotine patch was good.

Conclusions

The combination of lorcaserin and nicotine patch was well tolerated, associated with a relatively high smoking abstinence rate, and effectively prevented weight gain associated with quitting smoking.

Implications

This report provides an important contribution to the literature because it details evidence of a medication combination—lorcaserin and nicotine—that is effective for smoking cessation and for ameliorating weight gain associated with smoking cessation. For many smokers, postcessation weight gain is a major obstacle to quitting, and this medication combination provides a suitable treatment option for these smokers.

Clinical Trial Registration

NCT02906644
NimbleMiner
Authors: Topaz Maxim , Murga Ludmila , Bar-Bachar Ofrit , McDonald Margaret , Bowles Kathryn
Published: September 2019

This study develops and evaluates an open-source software (called NimbleMiner) that allows clinicians to interact with word embedding models with a goal of creating lexicons of similar terms. As a case study, the system was used to identify similar terms for patient fall history from homecare visit notes (N = 1 149 586) extracted from a large US homecare agency. Several experiments with parameters of word embedding models were conducted to identify the most time-effective and high-quality model. Models with larger word window width sizes (n = 10) that present users with about 50 top potentially similar terms for each (true) term validated by the user were most effective. NimbleMiner can assist in building a thorough vocabulary of fall history terms in about 2 hours. For domains like nursing, this approach could offer a valuable tool for rapid lexicon enrichment and discovery.
Gastrointestinal Adverse Events Observed After Chimeric Antigen Receptor T-Cell Therapy
Authors: Abu-Sbeih Hamzah , Tang Tenglong , Ali Faisal S. , Luo Wenyi , Neelapu Sattva S. , Westin Jason R. , Okhuysen Pablo C. , Foo Wai Chin , Curry Jonathan L. , Richards David M. , Ge Phillip S. , Wang Yinghong
Published: September 2019

Background:

Chimeric antigen receptor T-cell (CART) therapy can significantly improve outcomes for patients with certain hematologic malignancies. The most notable drawbacks of CART are cytokine release syndrome and CART-related encephalopathy syndrome. Gastrointestinal adverse events (GI-AEs) have not yet been reported in association with CART. Herein, we describe the incidence and clinical features of GI-AEs observed after CART.

Materials and Methods:

We report a case series of patients with hematologic malignancies who received CART, in a clinical trial or as the standard of care, and subsequently suffered from GI-AEs between 2012 and 2018.

Results:

In our cohort, 37 of 132 (28%) patients experienced GI-AEs. All 37 experienced diarrhea with a median onset of 7 days (interquartile range, 4 to 25 d) after CART infusion. The median age of these patients was 58 years. Most had diffuse large B-cell lymphoma (51%). Seventeen patients experienced cytokine release syndrome, and 9 experienced CART-related encephalopathy syndrome. The interleukin-6 antagonist was required in 15 patients. Overall, 49% of patients had grade 1 diarrhea, 32% had grade 2, and 15% had grade 3. Other gastrointestinal symptoms in these patients were abdominal pain (41%), nausea and vomiting (49%), fever (8%), bloody stools (3%), and abdominal distension (5%). The median duration of symptoms was 6 days (interquartile range, 3 to 9 d). In 32 patients who underwent imaging, 8 (25%) had findings suggestive of gastrointestinal tract inflammation. Nine (24%) patients experienced GI-AE recurrence after initial improvement. The symptoms were attributed to an alternative cause in 17 (13%) cases and to CART in 20 (15%) cases. One patient developed CART-related refractory colitis that eventually responded to antibiotics for pneumonia.

Conclusion:

CART-related GI-AEs occur in 15% of patients treated with CART. These symptoms are typically mild and self-limiting, requiring only symptomatic treatment. Nevertheless, CART may, in rare cases, lead to refractory colitis.
Air pollution, maternal hypertensive disorders, and preterm birth
Authors: Weber Kari A. , Yang Wei , Lurmann Frederick , Hammond S. Katharine , Shaw Gary M. , Padula Amy M.
Published: September 2019

Background:

Air pollution has been associated with hypertension and preterm birth. We examined if prenatal exposure to air pollutants was associated with gestational hypertension and if its association with preterm birth was modified by maternal hypertension.

Methods:

Data were from birth certificates and hospital discharge records of 252,205 women in San Joaquin Valley of California from 2000 to 2006. Air quality data were assigned from 24-hour averages of nitrogen dioxide (NO2), particulate matter <10µm (PM10) and <2.5µm (PM2.5), and carbon monoxide (CO) for different averaging periods over pregnancy. We estimated odds of preterm birth and multiplicative interaction between each pollutant and hypertensive disorder.

Results:

Among normotensive women, odds of preterm birth were slightly higher for higher exposure to all pollutants over the entire pregnancy. Patterns were similar among women with a hypertensive disorder. Among 32–36 week births, there was effect modification for exposure to NO2 and CO during the first trimester with higher odds among hypertensive women, and PM2.5 and CO during the last 6 weeks with higher odds among normotensive women. For 28–31 week births, there was effect modification by hypertensive status for PM10 exposure for the entire pregnancy, first, and second trimester with hypertensive women consistently having lower odds of preterm birth than normotensive.

Conclusion:

There was some evidence of effect modification in the direction counter to our hypothesis for exposure to PM10 and early preterm birth, and CO and PM2.5 at the end of pregnancy, but overall, hypertension did not modify the relationship between pollution and preterm birth.
Residential greenness, activities of daily living, and instrumental activities of daily living
Authors: Zhu Anna , Yan Lijing L. , Wu Chih-Da , James Peter , Zeng Yi , Ji John S.
Published: September 2019

Background:

We aimed to explore whether higher levels of residential greenness were related to lower odds of disabilities in activities of daily living (ADL) and instrumental activities of daily living (IADL).

Methods:

We included older adults 65 years of age or older from the Chinese Longitudinal Healthy Longevity Survey. Our exposure was Normalized Difference Vegetation Index in 500 m radius around residence. Our outcome was ADL and IADL. We used binary logistic regression and mixed-effects logistic regression to estimate the odds of ADL and IADL disabilities.

Results:

A total of 36,803 and 32,316 participants were included for the analysis of ADL and IADL, with 71.6% free of ADL disability and 47.3% free of IADL disability. In the logistic regression model, compared with the participants living in the lowest quartile of residential greenness, those in the highest quartile had a 28% (odds ratio [OR] = 0.72; 95% confidence interval [CI] = 0.65, 0.79) lower odds of ADL disability and a 14% (OR = 0.86; 95% CI = 0.77, 0.95) lower odds of IADL disability. A similar association was found in the mixed-effects logistic regression models. During the follow-up period, 5,004 and 4,880 healthy participants developed ADL and IADL disabilities. Per 0.1-unit increase in baseline annual average Normalized Difference Vegetation Index (NDVI) was related to an OR of 0.95 of developing ADL disability (95% CI = 0.93, 0.98) and IADL disability (95% CI = 0.91, 0.98).

Conclusions:

Our study suggests that increasing green space is associated with lower odds of ADL and IADL disabilities, which may reduce caregiver burden of long-term care for Chinese older adults.
Limited Sampling Strategies Supporting Individualized Dose Adjustment of Intravenous Busulfan in Children and Young Adults
Authors: Teitelbaum Zvi , Nassar Laila , Scherb Inna , Fink Dorit , Ring Gil , Lurie Yael , Krivoy Norberto , Bentur Yedidia , Efrati Edna , Kurnik Daniel
Published: September 2019

Background:

Therapeutic drug monitoring (TDM) for busulfan supports dose adjustment during conditioning for stem cell transplantation. The authors aimed to develop and validate limited sampling strategies (LSS) of 4–5 samples for a precise estimation of the area under concentration (AUC)-time curve of busulfan, in plasma as an alternative to an intensive sampling strategy (ISS) requiring 9–10 samples.

Methods:

ISS TDM data from 297 patients (≤18 years of age) were used. AUCLSS was calculated using the trapezoidal rule and multiple linear regression (MLR). Unlike more complex modeling methods, MLR does not require sophisticated software or advanced training of personnel. MLR coefficients were estimated in the development subset containing randomly selected 50% of the records and were then used to calculate the AUCLSS of the remaining records (the validation subset). The agreement between dose adjustment recommendations (DAR) based on ISS and LSS, in the validation subset, was evaluated by a Bland–Altman analysis. A DAR deviating from an ISS-based reference by <15% was deemed acceptable.

Results:

Twelve LSSs were acceptable. Sampling at 0, 120, 180, and 240 minutes after the start of the second infusion (LSS15) yielded the best performance, with DAR deviating from the reference by <10% for 95% of cases; the AUCLSS was determined as follows: AUCLSS = 74.7954 × C(0) + 81.8948 × C(120) + 38.1771 × C(180) + 138.1404 × C(240) + 54.1837. This LSS and LSS13 performed similarly well in an independent external validation.

Conclusions:

MLR-based estimates of AUCLSS provide DARs that deviate minimally from the reference. LSSs allow the reduction of patient discomfort, a ∼50% reduction of TDM-related workload for nursing staff and blood loss and a ∼25% reduction in laboratory workload. These benefits may encourage wider use of busulfan TDM, supporting safe and efficacious personalized dosing.
Long-term risk of de novo mental health conditions after hysterectomy with ovarian conservation: a cohort study
Authors: Laughlin-Tommaso Shannon K. , Satish Anisha , Khan Zaraq , Smith Carin Y. , Rocca Walter A. , Stewart Elizabeth A.
Published: September 2019

Objective:

The aim of this research was to study the long-term risk of de novo mental health conditions in women who underwent hysterectomy with bilateral ovarian conservation compared with age-matched referent women.

Methods:

Using the Rochester Epidemiology Project records-linkage system, we identified a historical cohort of 2,094 women who underwent hysterectomy with ovarian conservation for benign indications at age ≥18 years and with an index date between 1980 and 2002 in Olmsted County, Minnesota. Each woman was age-matched (±1 y) to a referent woman residing in the same county who had not undergone hysterectomy or any oophorectomy before the index date. These two cohorts were followed historically to identify de novo mental health conditions. We estimated hazard ratios (HRs) and 95% confidence intervals (95% CIs) using Cox proportional hazards models adjusted for 20 preexisting chronic conditions and other potential confounders. We also calculated absolute risk increases (ARIs) and reductions (ARRs) at 30 years of follow-up.

Results:

Over a median follow-up of 21.9 years, women who underwent hysterectomy at any age experienced increased risks of de novo depression (adjusted HR 1.26; 95% CI, 1.12-1.41; ARI 6.6%) and anxiety (adjusted HR 1.22; 95% CI, 1.08-1.38; ARI 4.7%). The association for depression increased significantly with younger age at hysterectomy, but did not vary significantly by indication. Interactions were not significant for anxiety.

Conclusions:

Hysterectomy, even with ovarian conservation, is associated with an increased long-term risk of de novo depression and anxiety, especially when performed in women who are younger.

Video Summary:

http://links.lww.com/MENO/A465.
The Incremental Hospitalization Cost of Significant Transport-Related Traumatic Brain Injury
Authors: Van Deynse Helena , Van Belleghem Griet , Hubloue Ives , Lauwaert Door , Moens Maarten , Pien Karen , Devos Stefanie , Putman Koen
Published: September 2019

Aim:

This study aims to determine the incremental cost of acute hospitalization for traumatic brain injury (TBI) compared with matched controls. A second purpose is to identify the factors contributing to this hospital costs.

Methodology:

Analyses were performed on administrative data for injured patients, hospitalized in Belgium between 2009 and 2011 following a road traffic accident. Cases were matched to a control with similar injuries but without TBI. The incremental hospitalization cost of TBI and the factors contributing to the hospital costs were determined using multivariable regression modeling with gamma distribution and log link.

Results:

A descriptive comparison of cases and controls shows clear differences in healthcare utilization and costs. The presence of a TBI increases the cost by a factor between 1.66 (95% confidence interval: 1.52-1.82) and 2.08 (95% confidence interval: 1.72-2.51). Regarding healthcare utilization, the most important determinants of hospital costs are surgical complexity, use of magnetic resonance imaging, intensive care unit admission, and mechanical ventilation.

Discussion:

To our knowledge, this is the first matched-control study calculating the incremental hospitalization cost of TBI. The insights provided by this study are relevant in the context of prospective payments and can be an incentive for investments in prevention policies and extramural care.
Is Robotic Gait Training Feasible in Adults With Disorders of Consciousness?
Authors: Williams Kathryn , Christenbury Jennifer , Niemeier Janet P. , Newman Mark , Pinto Shanti
Published: September 2019

Objective:

To investigate the feasibility and safety of robotic-assisted gait training (RAGT) in adults with disorders of consciousness (DoC).

Setting:

Inpatient rehabilitation hospital.

Participants:

Four adult male patients with traumatic brain injury and DoC.

Design:

Subjects participated in RAGT with body weight support for 5 to 20 minutes, over 1- to 2-week periods.

Main Measures:

Primary measures included vital signs, walking parameters, pain, arousal, and Agitation Behavior Scale scores. Additional data included Modified Ashworth Scale, Coma Recovery Scale-Revised, and Rancho Los Amigos Scale scores.

Results:

All participants safely completed at least one session of RAGT with body weight support with safe vital signs and low agitation levels. Two adverse events occurred (increased somnolence and pain due to harness placement), which were not considered severe. All subjects emerged out of DoC at which point research protocol was stopped.

Conclusions:

Findings suggest inpatient-based RAGT may be safe and feasible to consider when developing a therapy plan of care in adults with DoC.
The Experience of Caregivers Following a Moderate to Severe Traumatic Brain Injury Requiring ICU Admission
Authors: Kreitzer Natalie , Bakas Tamilyn , Kurowski Brad , Lindsell Christopher J. , Ferioli Simona , Foreman Brandon , Ngwenya Laura B. , Thomas Stephanie , Keegan Sara , Adeoye Opeolu
Published: September 2019

Objectives:

Survivors of moderate and severe traumatic brain injury (TBI) require substantial care, much of which is ultimately provided by friends and family. We sought to describe the unmet needs of informal caregivers.

Design:

Qualitative, semistructured interviews with informal caregivers of moderate and severe TBI survivors were conducted 72 hours, 1 month, 3 months, and 6 months after injury.

Setting:

Intensive care unit of a level 1 trauma center.

Participants:

Informal caregivers were friends or family who planned to provide care for the patient. Patients were 18 years or older with a moderate to severe TBI, and not expected to imminently die of their injuries.

Measurements and Main Results:

Eighteen patient-caregiver dyads were enrolled. Fifty-three interviews with caregivers were completed and analyzed over the course of 6 months. Three themes were identified in the qualitative analysis: caregiver burden, caregiver health-related quality of life, and caregiver needs for information and support.

Conclusions:

This study provides new information about the experience of informal caregivers during the 6 months after their friend or family member survived a moderate to severe TBI. Interventions to promote caregiving may be a substantial opportunity to improve patient-centered outcomes following TBI.
CHARACTERIZATION BY FRACTAL DIMENSION ANALYSIS OF THE RETINAL CAPILLARY NETWORK IN PARKINSON DISEASE
Authors: Shi Ce , Chen Yihong , Kwapong William Robert , Tong Qiaowen , Wu Senxiang , Zhou Yuheng , Miao Hanpei , Shen Meixiao , Ye Hua
Published: September 2019

Purpose:

To characterize retinal capillary complexity by optical coherence tomography angiography in Parkinson disease.

Method:

Twenty-five Parkinson disease patients and 25 age- and gender-matched healthy controls were recruited. Optical coherence tomography angiography and optical coherence tomography imaged the superficial and deep retinal capillary plexuses and retinal structure. Retinal capillary skeleton density, retinal capillary perfusion density, and fractal dimension analysis of retinal capillary complexity were performed in the total annular zone and quadrant sectors. The thickness of retinal nerve fiber layer, ganglion cell layer and inner plexiform layer, and total retinal thickness were extracted from retinal structural images. Relationships among the retinal capillaries, retinal structure, and clinical parameters were analyzed.

Results:

The superficial retinal capillary plexus in Parkinson disease patients had lower retinal capillary skeleton and perfusion densities and capillary complexity in the total annular zone and all quadrant sectors compared with healthy control subjects. The deep retinal capillary plexus retinal capillary complexity was decreased in the total annular zone and the superior and inferior quadrants. The retinal capillary complexity in the inferior quadrant was negatively correlated with the best-corrected visual acuity and disease duration (r = −0.61, r = −0.43, respectively, both P < 0.05).

Conclusion:

As determined by fractal analysis, retinal capillary complexity can be an objective biomarker in Parkinson disease.