bluuebunny/crossref_metadata_2025_split huggingface dataset:
Unloading Frac Hits in Gas Wells: How Does the Nitrogen Injection Rate and Pressure Affect the Unloading Process?
Authors: Cedeno Miguel Angel 
Published: June 2021

Abstract
The unconventional resources development has grown tremendously as a result of the advancement in horizontal drilling technology coupled with hydraulic fracturing. However, as more wells are drilled and fractured close to each other, frac hits have become a major challenge in these wells. The aim of this work is to investigate the effect of nitrogen injection flow rate and pressure on unloading frac hits gas wells in transient multiphase flow. A numerical simulation model was created using a transient multiphase flow simulator to mimic the unloading process of frac hits by injecting nitrogen from the surface through the annulus section of the well. Many simulation cases were created and analyzed to comprehend the effect of the nitrogen injection rate and pressure on the unloading of frac hits. The model mimicked real field data from currently active well in the Eagle Ford Shale. The results showed that as the nitrogen injection pressure increases, the nitrogen volume and the time to unload the frac hits decrease. On the other hand, increasing the injection rate of nitrogen will increase the nitrogen volume required to unload the frac hits. In addition, the time to unload frac hits will be decreased as the nitrogen injection rate increases. These results indicate that the time required to unload frac hits will be minimized if higher flow rates of nitrogen were utilized. Nonetheless, the volume of nitrogen required to unload the frac hits will be maximized. An important observation to highlight is that the operators can save money by reducing the time for injecting nitrogen. This observation was verified when increasing the injection pressure in the frac hit well in the Eagle Ford Shale, the time of injection was reduced 20%. This study presents the effects of nitrogen injection flow rate and injection pressure for unloading frac hits in gas wells. Due to the lack of published studies about this topic, this work can serve as a practical guideline for unloading frac hits in gas wells.
Maximising Infill Well Oil Recovery with 4D Seismic and Reservoir Simulation
Authors: Daramola Babalola 
Published: June 2021

Abstract
This publication presents how 4D seismic and reservoir simulation techniques were used to optimise the trajectory of an infill production well in a producing oil field. The A6 infill well target in Field X offshore Nigeria was planned as a 12000 feet horizontal drill well with a 4900 feet gravel pack completion in the reservoir formation. The initial well trajectory delivered early water breakthrough and low oil recovery. The well planning team resolved the issue by reconciling the well trajectory and completion data in the geologic and reservoir simulation models, and used 4D seismic difference maps to validate the infill drilling target. Alternative well trajectories were then simulated to improve reservoir penetration and to place the well up-structure and away from the current oil water contact.
The optimised well trajectory increased the incremental oil recovery from 1.8 MMSTB to 3.0 MMSTB, and significantly boosted the project economics. The well came online in 2016, and delivered higher oil rates than the forecast. 4D seismic and reservoir simulation techniques optimised the infill well trajectory, delayed water breakthrough, and maximised oil recovery. Nearby wells can be shut in during drilling operations to minimise the risk of drilling losses and well integrity failures. Oil asset net present value can also be preserved and boosted with water injection performance monitoring, zonal testing, short circuit diagnosis and remediation, and water shut off work-overs. This paper presents a case study of an infill production well placement optimised with 4D seismic and reservoir simulation tools, and simplifies the infill well placement value creation process.
Investigation on the Absorption Bands Around 3.3 μm in CRISM Data
Authors: Manzari Paola , Marzo Cosimo , Ammannito Eleonora 
Published: June 2021

Abstract
While analyzing NIR-IR CRISM data on a site in Oxia Planum area, in the view of the ExoMars2022 mission, absorptions around 3.3 µm were noted in some pixel spectra. Absorptions in the range 3.1–3.6 mm are under the spotlight in planetary contexts since hydrocarbons molecules show bands in this range. Consequently, we started to search eventual hydrocarbon compounds on Mars surface, using CRISM data in the range 3.2–3.4 mm. To date, methane has been the unique hydrocarbon detected on Mars. Like other hydrocarbons, methane shows absorptions around 3.3 mm. Hence, we begun the investigation on CRISM data, on that locations where methane was detected and where it could form on the basis of the mineralogy of the specific site. The datasets chosen for this study include some sites of observations in Oxia Planum area, Gale Crater and Nili Fossae area. Beside the study of CRISM IR data, in the event that some observed absorptions were related to methane, we tried to calculate a theoretical lower limit of detection for each observation in CRISM data. This was performed using the Planetary Spectrum Generator, simulating the CRISM spectra of the different sites, with the diverse concentrations of CH4. These simulations served to establish the relation between concentration and methane band depths, as seen by CRISM spectrometer. Then, mapping the Modified Gaussian Model (MGM) fit on CRISM data, we extracted the band parameters of the absorptions in the 3.3 µm spectral region. Aside rare, suspected absorptions, an artifact was highlighted. Therefore, we took measures to avoid, as more as possible, this artifact from the interpretation of the 3.3 mm absorptions: distribution of clusters of pixels not vertically stacked and a rather conservative threshold on depth value. As result, we found interesting clusters of pixels which spectra overcome the imposed threshold. Furthermore, the threshold value varies from one observation to another, in a range between 0.0136–0.0237, that would correspond to a range of theoretical lower limits of concentration between 180 and 600 ppbv. Despite all the precautions, we consider that part of these absorptions could still be an artifact. Nevertheless, the aim of this paper is to show that CRISM data can show theoretically absorptions of hydrocarbons, and methane, in such quantities that in some observations are compatible with the order of the methane spikes effectively detected on Mars. Even if this work does not confirm nor deny the occurrences of methane seepages or hydrocarbons in the investigated images, it shows a possible method for searching hydrocarbons in CRISM data and for assessing a confidence limit in the detection methane band in CRISM data.
Estimating carbon storage potential of fallow weeds in rice cropping systems
Authors: Huang Min , Chen Ge , Cao Fangbo , Chen Jiana 
Published: June 2021

Abstract
Weeds occurred during the fallow season can well perform the function of carbon (C) storage due to receiving little human disturbance. This study aimed to evaluate the C storage potential of fallow weeds in rice cropping systems. A six-region, two-year on-farm investigation and a three-year tillage experiment were conducted to estimate C storage in fallow weeds in rice cropping systems. The on-farm investigation showed that the average mean C storage in fallow weeds across six regions and two years reached 112 g m–2. The tillage experiment indicated that no-tillage practices increased C storage in fallow weeds by 80% on average as compared with conventional tillage. The results of this study not only contribute to an understanding of C storage potential of fallow weeds in rice cropping systems, but also provide a reference for including fallow weeds in the estimation of vegetative C sink. Further investigations are required to determine the effect of C input from fallow weeds on C balance of rice paddies in order to comprehensively evaluate the role of fallow weeds in C cycling in rice cropping systems.
Automatic locking of a parametrically resonating, base excited, nonlinear beam
Authors: Bucher Izhak , Shaya Nir Ben , Dolev Amit 
Published: June 2021

Abstract
Presented is a closed-loop, phase control scheme of a parametrically excited nonlinear structure, capable of stabilizing open-loop unstable solutions while automatically locking onto a desired point on any solution branch. Axially driven slender beams develop large transverse vibration under suitable amplitude and precise frequency base-excitation. The latter can induce parametric excitation along with a nonlinear response. The phase-lag of the 2:1 response over the excitation serves as a tunable parameter affecting the operating point of steady vibrations of a limit cycle. The operating point is tuned to exhibit great sensitivity to small interaction forces thus paving the way towards an ultrasensitive sensor. The paper analyzes the behavior of the mentioned configuration using asymptotic analysis, numerical simulations and an experimental system. Detailed analysis of the dynamical behavior, experimental verifications and demonstrations shed light on some features of the system dynamics.
Study Protocol of an Open Labelled Randomised Controlled Trial of Perioperative Oral Nutrition Supplement in Breast and Colorectal Cancer Patients Undergoing Elective Surgery
Authors: Wong Ting Xuan , Chen Seong Ting , Ong Shu Hwa , Shyam Sangeetha , Palayan Kandasami , Chee Winnie Siew Swee 
Published: June 2021

Abstract
Background: While it is well established that perioperative use of oral nutrition supplement (ONS) improves nutrition status among severely malnourished surgical cancer patients, the evidence requires further substantiation for non-severely malnourished patients with cancer. This protocol paper presents the rationale and design of a randomised controlled trial to evaluate the effectiveness of preoperative as well as an extended 3-month postoperative use of ONS on nutritional and clinical outcomes among patients undergoing elective surgery for breast and colorectal cancer. Methods: Patients with primary breast and colorectal cancer undergoing elective surgery are recruited from two tertiary hospitals. Eligible patients are assigned into one of the three intervention arms: i) Group SS will receive ONS in addition to their normal diet up to 14 days preoperatively and postoperatively up to discharge, ii) Group SS-E will receive ONS in addition to their normal diet up to 14 days preoperatively, postoperatively up to discharge and for an extended 3 months after discharge and iii) Group DS will receive ONS in addition to their normal diet postoperatively up to discharge from the hospital. The ONS is a standard formula fortified with lactium to aid in sleep for recovery. The primary endpoints include changes in weight, body mass index (BMI), serum albumin and prealbumin levels, while secondary endpoints are body composition (muscle and fat mass), muscle strength (handgrip strength), energy and protein intake, sleep quality, haemoglobin, inflammatory markers (transferrin, Hs-CRP, interleukin-6), stress marker (saliva cortisol), length of hospital stay and postoperative complication rate. Discussion: This trial is expected to provide evidence on whether perioperative supplementation in breast and colorectal cancer patients presenting with high BMI and not severely malnourished but undergoing the stress of surgery, would be beneficial in terms of nutritional, and clinical outcomes. Trial registration: ClinicalTrial.gov with the identifier: NCT04400552. Registered on 22 May 2020, retrospectively registered.
Effects of Probiotic Mixture Supplementation and Evaluation of Intestinal Mucosal Tolerance and Gut Microbiome in Newborns with Perinatal Asphyxia Receiving Hypothermic Treatment: A Randomized, Multicentric, Blinded, Controlled TRIAL (VISNAT)
Authors: Baldassarre Maria Elisabetta , Panza Raffaella , Mauro Antonio Di , Fanelli Margherita , Mastromarino Paola , Scacco Salvatore , Capozza Manuela , Capodiferro Donatella , Laforgia Nicola 
Published: June 2021

Abstract
IntroductionNeonatal encephalopathy is still a major cause of mortality and morbidity for newborns, although hypothermia treatment has improved the prognosis of term newborns with hypoxic-ischemic injury.Recent evidence suggests that one of the crucial but understudied mechanisms of secondary neuronal injury after global hypoxic-ischemic injury is inflammation.Hence, blocking the inflammatory reaction promotes neuroprotection and has a potential for use in the clinical treatment of ischemic brain injury.Many preclinical studies have shown bidirectional interactions between the central nervous system, the enteric nervous system, and the gastrointestinal tract, suggesting a prominent role for the gut microbiota in these gut-brain interactions. Early human studies suggest that altering the microbiota with beneficial bacteria, or probiotics, can lead to changes in brain function, as well as subjective reports of mood.Methods and analysisThe VISNAT trial is a PILOT STUDY developed according to SPIRIT checklist. It is a randomized, placebo-controlled, blinded, multicentre superiority trial with two parallel groups and a primary outcome of mortality and/or disability at 18 months of age.The experimental intervention will consist in administrating a high-dose multi-strain probiotic (SIVOMIXXTM) for 30 days in addition to hypothermic therapy.Primary outcome will be to compare mortality and/or disability at 18 month of age between the two groups. Disability will be assessed by means of the Bayley Mental Development Index. Secondary outcomes will be to compare inflammatory cytokines level and brain injury biomarkers (i.e. Tau and neurofilament light protein) between groups.A subgroup analysis will be performed stratifying patients according to both probiotic/placebo treatment and breast/artificial milk.DiscussionProbiotics supplementation represents a simple and reproducible intervention. If proven effective, probiotics supplementation in asphyxiated babies would improve clinical outcomes and reduce health cost. Hence, this study may cast a new light on the management of hypoxic-ischemic encephalopathy. Trial registration numberStudy has been registered on clinicaltrials.org on 23rd October 2019 with number NCT04145713. Trial StatusThe present trial (VISNAT Study Version 1.0 - 23 October 2019) has been approved by the Ethics Committees of the coordinator centre “Azienda Ospedaliera Universitaria Consorziale Policlinico di Bari”. Approval from the Ethics Committees of each participating hospital has also been requested. Enrollment of patients is planned to start in July 2021 and should last approximately 2 years.
Genetic Risk Score for Predicting Schizophrenia Using Human Chromosomal-Scale Length Variation
Authors: Toh Christopher , Brody James P. 
Published: June 2021

Abstract
Studies indicate that schizophrenia has a genetic component, however it cannot be isolated to a single gene. We aimed to determine how well one could predict that a person will develop schizophrenia based on their germ line genetics. We compared 1129 people from the UK Biobank dataset who had a diagnosis of schizophrenia to an equal number of age matched people drawn from the general UK Biobank population. For each person, we constructed a profile consisting of numbers. Each number characterized the length of segments of chromosomes. We tested several machine learning algorithms to determine which was most effective in predicting schizophrenia and if any improvement in prediction occurs by breaking the chromosomes into smaller chunks. We found that the stacked ensemble, performed best with an area under the receiver operating characteristic curve (AUC) of 0.545 (95% CI 0.539-0.550). We noted an increase in the AUC by breaking the chromosomes into smaller chunks for analysis. Using SHAP values, we identified the X chromosome as the most important contributor to the predictive model. We conclude that germ line chromosomal scale length variation data could provide an effective genetic risk score for schizophrenia which performs better than chance.
What is the difference in pedicle morphology of the fifth lumbar vertebra between isthmic and degenerative L5-S1 spondylolisthesis? An anatomic study of 328 patients via multi-slice spiral computed tomography
Authors: Tang Chao , Liao Ye Hui , Tang Qiang , Ma Fei , Wang Qing , Zhong DeJun 
Published: June 2021

Abstract
Purpose

The purpose of this study was to investigate and determine whether there are differences in L5 pedicles morphology between isthmic and degenerative L5-S1 spondylolisthesis.
Methods

One hundred and nineteen patients with isthmic spondylolisthesis and 45 patients with degenerative spondylolisthesis at L5-S1 were enrolled in the IS group and DS group, respectively, and 164 lumbar disc herniation patients without spondylolysis or spondylolisthesis were classified into the normal (NL) group. A series of pedicle parameters of the fifth lumbar vertebra, including pedicle length (PL), pedicle width (PW), pedicle screw trajectory length (PSTL), pedicle height (PH), and the pedicle camber angle (PCA) were measured using multi-slice spiral computed tomography (MSCT). The slip distance of the L5 vertebra was measured on radiography, and the percentage of slip was also recorded.
Results

The pedicles of the fifth lumbar vertebra were shorter and wider, and the PCA was larger in the IS group compared to the DS group and NL group. On the contrary, the pedicles in the DS group were elongated and thinner, and the PCA was smaller. The pedicle parameters of PL were significantly positively correlated with the percentage of slip in the DS group, but PW and PCA were negatively correlated with the percentage of slip. There was no correlation between the percentage of slip and L5 pedicle parameters in the IS group.
Conclusions

The L5 pedicles morphology in L5-S1 isthmic spondylolisthesis shows abduction, shortness, and width, while that in the degenerative spondylolisthesis shows adduction, lengthening, and thinning compared with the normal populations. The morphology changes may be the result of pedicle stress remodeling in the development of spondylolisthesis, which should be taken into consideration when placing at the insertion of pedicle screws.
In Silico Identification of Potential Therapeutic Agents for COVID-19 Based on Molecular Docking Study of Main Protease and Receptor Binding Domain of Spike Protein.
Authors: Eskandari Vajiheh 
Published: June 2021

Abstract
Severe acute respiratory syndrome coronavirus (SARS-CoV-2) enter the cell by interacting with human angiotensin-converting enzyme 2 (ACE2) receptor through the receptor-binding domain (RBD) of S-protein. In the cell the viral 3-chymotrypsin-like cysteine protease (3CLp) enzyme is essential for its life cycle and controls coronavirus replication. Therefore the S-RBD and 3CLp are hot targets for drugs discovery against SARS-CoV-2. This study was to identify repurposing drugs using in-silico screening, docking and molecular dynamics simulation. The study identified Dibenzoyl Thiamine, Folic Acid and Vitamin B12 against the RBD of S-protein and Dibenzoyl Thiamine, Folic Acid, Fursultiamine and Riboflavin to 3CLp. The strong and stable binding of these safe and cheap vitamins at the important residues (R403, K417, Y449, Y453, N501 and Y505) in S-protein –ACE2 interface and 3CLp active site residues (His 41 and Cys 145), indicating that they could be valuable repurpose drugs for inhibiting SARS-CoV-2 entry into the host and replication.
Efficacy and Safety of Thread Embedding Acupuncture for Facial Expression Muscles Atrophy After Peripheral Facial Paralysis: Study Protocol for a Randomized Controlled Trial
Authors: Yu Binyan , Xuan Lihua , Jin Yutong , Chen Shan , Liu Shan , Wan Yijia 
Published: June 2021

Abstract
Background

Facial expression muscles atrophy is one kind of sequelae after peripheral facial paralysis. It causes critical problems in facial appearance of patient as well as social and psychological problems. This study aims to evaluate the efficacy and safety of Thread-embedding acupuncture (TEA) for the management of facial expression muscles atrophy after peripheral facial paralysis.
Methods

This is a patient-assessor blinded, randomized, sham-controlled trial. A total of 56 eligible patients will be randomly allocated to a TEA group (n = 28) or a sham TEA (STEA) group (n = 28). Both groups will receive TEA or STEA treatment at 2 predefined points once a week for 8 weeks. Additionally, both groups will receive the same acupuncture treatment twice a week for 8 weeks as a concurrent treatment. Changes in facial expression muscle thickness ratio of the affected/healthy side measured by B-mode ultrasonography will be assessed at baseline and at 10 weeks after screening as the primary outcome. Furthermore, the House-Brackmann Grade and lip mobility score will be measured and analyzed as secondary outcomes. Secondary outcomes will be assessed at baseline and at 4, 8, 10 and 12 weeks after screening.
Discussion

The study will compare TEA with sham TEA to explore the feasibility for TEA in improving symptoms caused by facial expression muscles atrophy after peripheral facial paralysis.
Trial registration:

Chinese Clinical Trial Registry, ChiCTR1900027170. Registered on 3 November 2019, http://www.chictr.org.cn/edit.aspx?pid=45173&htm=4
Effects of Integrative Medicine on The Post-Stroke Cognitive Impairment (PSCI) Patients: A Study Protocol for A Randomized Multicentric Controlled Trial
Authors: Li Xinyun , He Kelin , Wu Lei , Zheng Weijun , Luo Kaitao , Li Liping , Zan Daowei , Ni Fengjia , Ma Ruijie , Ni Fengjia 
Published: June 2021

Abstract
Background

Due to limitation of rehabilitation in cognitive impairment after stroke, as the main parts of traditional Chinese medicine, acupuncture and herbs have their advantage effect in clinical practice for post-stroke cognitive impairment (PSCI). Therefore, forming a standardized and propagable TCM project of PSCI becomes necessary. This trail will solve the above problem.
Methods

In total, 126 stroke patients will be recruited from the inpatient and outpatient departments of The Third Affiliated Hospital of Zhejiang Chinese Medical University (Hangzhou, China), Jiaxing Hospital of Traditional Chinese Medicine and Hangzhou Hospital of Traditional Chinese Medicine to participate in this study with randomization. All participants will continue to receive basic treatment and cognitive function regular training, while successive 12 weeks of acupuncture and herbs will be provided to patients assigned to the integrative medicine group. Montreal cognitive assessment (MOCA), mini-mental state examination, activity of daily living (ADL) score, hamilton depression scale (HAMD), functional near-infrared spectroscopy (fNIRS) and RESTing-state functional MRI (RS-fmri) will be used to measure the outcomes.
Discussion

This trial may provide high-quality RCT evidence regarding the clinical effectiveness and safety of acupuncture and herbs for PSCI patient.
Trial registration:
ClinicalTrials.gov (ID: NCT 04596072)