bluuebunny/crossref_metadata_2025 huggingface dataset:
Solving the Hydraulic Fracturing Puzzle in the HPHT KG Basin of India with Geomechanics-Enabled Design and Execution
Authors: Gondalia Ravi Ramniklal , Kumar Rajeev Ranjan , Nand Ujjwal , Bandyopadhyay Atanu , Narayan Shashank , Bordeori Krishna , Singh Mukund Murari , Shah Arpit , Das Santanu , Rao Dasari Papa , Shaik Moulali
Published: January 2019

The Mandapeta-Malleswaram field in India comprises Triassic-Jurassic age sands found at 4000m– 4500m depth, where reservoir pressure ranges 6,000 psi to 9,500psi with static temperature up to 340°F. This tectonically active basin with strike slip stress regime causes a heterogeneous distribution of in-situ stress which complicates the design and execution of effective hydraulic fracturing treatments. Previous attempts at fracturing from 2013 to 2017 were not successful and geomechanics inputs were different from actual values. This paper describes the lifecycle of a production enhancement project, from construction of a geomechanics-enabled mechanical earth model (MEM) to the successful design and execution of fracturing jobs on nine wells increasing proppant placement by 250% compared to previous hydraulic fracturing campaign and achieving 730% incremental gain in gas production compared to pre- fracturing production.

Challenges like fracture modeling in tectonically stressed formations, issues of proppant admittance, and complicated fracture plane growth in highly deviated wells (>65°) were overcome by Geomechanical modeling. The modeling incorporated advanced 3D anisotropy measurements, providing better estimation of Young's modulus, Poisson's ratio, and horizontal stresses, resulting in realistic estimation of closure and breakdown pressure. Fault effects were modeled and taken into consideration for perforation depth selection and estimation of pumping pressure with model update based on extensive Minifrac injections and analysis.

This study describes the results of injection tests (step rate, pump in-flowback, and calibration injection tests) carried out in the field addressing specific challenges in each well. Pre frac diagnostic injection and decline analysis was used to calibrate the MEM and tailor the design for every well. Proper job preparation for well completions and extensive stability testing involving a borate-based fluid system has reduced the screen out risk and enabled successful fracture placement. Effective pressure management on the job eliminated the problem with frequent screen outs and led to successful execution of all nine jobs while increasing the average job size from 30 t to ~150 t of proppant per stage.

From this project, a practical guide to address issues of multiple complexities occurring simultaneously in a reservoir, such as the presence of tectonic stress, fracture misalignment, fissure mitigation, and high tortuosity was developed for future application in tectonically complex fields.
Multidisciplinary Data Gathering to Characterize Hydraulic Fracture Performance and Evaluate Well Spacing in the Bakken
Authors: Lorwongngam Apiwat Ohm , Cipolla Craig , Gradl Christian , Gil Cidoncha Jose , Davis Bruce
Published: January 2019

To effectively drain hydrocarbon from unconventional plays, operators have been optimizing their drilling spacing unit (DSU) well spacing for many years. This paper presents a continuous improvement of Bakken well spacing using trial pads with smaller spacing and multidisciplinary data gathering to understand the most effective spacing between wells.

The operator's standard well spacing between Middle Bakken (MB) wells in the East Nesson (EN) area [Alger Field] ranges from 500 to 700 ft. To understand the optimum spacing between wells in this area, the operator trialed well spacing of 500 ft between like formations. The spacing between Middle Bakken and Three Forks wells was 250 ft. Data gathered during the spacing trial included microseismic, microseismic depletion delineation (MDD), radioactive (RA) tracers, chemical tracers, image logs, pressure measurements during completion/flowback/early-time production, and diagnostic fracture injection tests (DFITs). The data was used to calibrate advanced hydraulic fracture models and guide next-generation reservoir simulation history matching to characterize multiwell production behavior.

The MDD in the parent well provided data to "map" drainage patterns, showing that drainage was limited to the MB formation. However, microseismic showed that hydraulic fracture height extended from the Three Forks second bench (TF2) up through the Three Forks first bench (TF1), Middle Bakken, and into the overlying Lodgepole (LP)—connecting the entire Bakken petroleum system. The microseismic also showed asymmetric fracture growth toward the parent well in the DSU, but the asymmetry diminished as completions progressed away from the parent well. In addition to the MB-TF connectivity indicated from the microseismic, RA tracers pumped from a TF2 well were detected in a Middle Bakken well. The implied transport of proppant from a lower TF completion to the MB increases the likelihood of production communication between formations. Chemical tracers (oil and water) pumped during hydraulic fracturing operations were found from one end of the pad to another (over 2,500 ft) regardless of formation; another confirmation of hydraulic communication between Middle Bakken and Three Forks wells.

The hydraulic fracture model was calibrated using microseismic data and used for subsequent reservoir simulation history matching. The workflow consisted of modeling the parent well hydraulic fractures and history matching production, performing geomechanical modeling to determine the effects of parent well depletion on 3D stress state for hydraulic fracture modeling of the infill wells, and production history matching of the entire pad. The modeling showed significant fracture-to-fracture communication and well-to-well interference. The operator quickly used these learnings to optimize well spacing across the area to maximize DSU value.
Utilization of Far Field Diverters to Mitigate Parent and Infill Well Fracture Interaction in Shale Formations
Authors: Zhang Junjing , Cramer David D. , McEwen Jamie , White Matt , Bjornen Kevin
Published: January 2019

Hydraulic fracturing treatments in shale infill wells are often impacted by existing parent well depletion and asymmetrical fracture growth. These phenomena can result in excessive load water production, deposition of proppant and deformation of casing in the parent well, and unbalanced stimulation of infill wells. This study determines the effectiveness of particulate materials for mitigating the above negative outcomes by bridging near the extremities of dominant fracture wings, i.e., far field diverting agents.

Fracture propagation was modeled to characterize the width profile at fracture extremities in a depleted stress environment. A slotted-disk device was used to evaluate and optimize particulate blends for bridging slots representative of width near the fracture tip. Rheological tests replicating the downhole environment were used to formulate a system for transporting the diverting materials. Statistical analysis of 511 fracture hits at 30 parent wells was performed on key treatment indicators by the category of diverter type and post-hit parent well condition. Production trends of the influenced wells were compared to area-specific type curves and offset wells without diverter trials.

Based on the simulation and testing results, two types of high-graded far field diverter systems were field tested in a shale play: dissolvable, extremely fine particulate mixed with 100 mesh sand, and mixtures of nominal 325 mesh silica flour and 100 mesh sand. Proppant dust collected at the fracturing site was also evaluated for replacing commercial silica flour. High-graded blends of the above diverting systems demonstrated superior frac-hit and productivity metrics as compared to the base case of not applying far field diverters. The silica flour and 100 mesh sand mixture performed on par with the significantly more expensive blend of dissolvable fine particulate and 100 mesh sand. Guar borate crosslinked gel was an effective carrying fluid for transporting diverting materials to the fracture extremities.

Statistical analysis of fracture hit events shows that the application of far field diverters did not reduce the magnitude of pressure buildups during fracture hits; however, it significantly increases the post-hit pressure falloff rate at the parent wells. Based on the area-specific type curves, pumping far field diverters increased the P50 EUR by about 6% compared with the base cases of not applying diverters. For all the wells impacted by far field diverters, the infill wells saw larger benefits with an increment of P50 EUR by about 7% compared with the parent wells.
Investigation of Non-Ideal Diagnostic Fracture Injection Tests Behavior in Unconventional Reservoirs
Authors: Mohamed Mohamed Ibrahim , Salah Mohamed , Coskuner Yakup , Ibrahim Mazher , Pieprzica Chester , Ozkan Erdal
Published: January 2019

Diagnostic fracture injection test (DFIT) has become a valuable tool to quantify reservoir properties and hydraulic fracture characteristics. The pressure decline response of DFIT test reflects the process of fracture closure and the flow capacity of the reservoir. Previous literature provided simplifying assumptions to analysis the DFIT. However, operating companies often face challenges in the DFIT data interpretation due to several complex factors that result in non-ideal DFIT behavior and inconsistent results that lead to significant incorrect estimation of reservoir properties and fracturing parameters, including interaction with natural fractures, heterogeneous rock properties, variable storage, etc.

The objective of this paper is to investigate the non-ideal DFIT behavior and factors that affect DFIT data and interpretations. The paper explained the flow regimes observed before closure and after closure during DFIT under complex reservoir conditions of natural fracture activation and fracture tip extension for reliable estimation of reservoir properties and fracture characteristic from actual field DFIT data. The overall fall-off period is analyzed using pressure transient analysis diagnostic plots and leak-off modeling. The transient pressure during the fall-off period is highly affected by the residual leak-off and continuing after flow that could disturb formation flow regimes during the test, affecting the ability to get correct pore pressure or formation permeability.

The paper explains the various mechanisms affecting the pressure transient behavior during DFIT and adapts the wellbore and leak-off process to be able to observe reservoir response and get more realistic fracture characteristics and reservoir properties.
Real Time Analysis of Formation Face Pressures in Acid Fracturing Treatments
Authors: Pandey Vibhas J. , Burton Robert C. , Capps Kay
Published: January 2019

Objective

Knowledge of fracture entry pressures or the formation face pressures during Acid Fracturing treatments can help in evaluating the effectiveness of the stimulation treatment in dynamic mode and can also enable and improve real-time decisions during the execution of treatment. In this paper, details of the methods and tools employed to generate formation face pressures in real-time mode with the help of live bottomhole pressure data, is discussed in detail.

Methods, Procedures, Process

The majority of the horizontal wells considered for this study were drilled and completed in the North Sea with permanent bottomhole pressure gauges that enabled constant monitoring of well pressures. The tool in discussion uses the combination of treatment data such as surface pressure, fluid density, injection rates, type of fluid, wellbore description, gauge depth, and wellbore deviation, along with bottomhole pressures to generate formation face pressures just outside the casing at active perforation depth. The tool carries out the calculations as the treatment is being pumped thus providing a dynamic array of several important parameters and can also evaluate the treatment after it has been executed.

Results, Observations, Conclusions

Acid fracturing treatments combine the basic principles of hydraulic fracturing and acid reaction kinetics to stimulate acid soluble formations. It is customary to start the treatment with a high viscosity pad to generate a fracture geometry and follow it up with acid to react with the walls of the fracture and etch it differentially. The non-uniform etching action of the acid creates an uneven surface on fracture walls that provides the requisite fracture conductivity which is key to enhancing the well performance. The effectiveness of a treatment schedule can be ascertained by determining and analyzing the pressure behavior during the injection process. Several acid fracture treatments were analyzed using the tool and led to important conclusions related to fracture propagation modes, acid exposure times and effectiveness of given acid types. The results had a direct influence on modification of treatment designs and pump schedules to optimize treatment outcomes.

Novel Ideas

The knowledge of formation face pressures is critical to the success of hydraulic fracturing treatments, especially in multi-stage and multiple perforation cluster type horizontal well completions. The tool developed in the study helps generate information that predicts pressures at fracture entry in real-time mode.
Understanding Frac Fluid Distribution of an Individual Frac Stage from Chemical Tracer Flowback Data
Authors: Tian Wei , Darnley Alex , Mohle Teddy , Johns Kyle , Dempsey Chris
Published: January 2019

A data set is presented which involves pumping multiple, unique chemical tracers into a single ‘Wolfcamp B’ fracture stage. The goal of this tracer test is to shed light on the flowback characteristics of individually tagged fluid & sand segments by adding another layer of granularity to a typical tracer flowback report. The added intra-stage level detail can provide insights into fracture behavior when stimulating shale reservoirs by looking at individual fluid segment tracer recoveries. This data set could aid in the interpretation of:

Identifying fluid segments placed outside of the P-SRV (Propped Stimulated Reservoir Volume) Fracture Complexity

A total of 12 water phase tracers and 12 oil phase tracers were injected sequentially from "Pad" to "Flush". After pumping the pad stage, unique tracers were used to tag the "Proppant Laden Fluid" from the 0.2 ppa 100 mesh sand stage to the 2 ppa 40/70 mesh sand stage, before going to flush. The flush volume was not traced. Upon flowback, produced fluids were analyzed for the concentration of each tracer within the produced fluid samples. The first goal was to determine whether any traced fluid would be placed within "unpropped" SRV. The second goal was to determine the order of load fluid returns, to verify the "first-in, last-out" phenomenon, and to ascertain any degree of fluid mixing, which could be an indication of increased fracture complexity.

The results illustrate the average tracer concentration and arrival time of each traced fluid segment, which was then used to characterize the fracture stage. All tracers were detected in the produced fluid samples, indicating that no traced segment was placed outside of the propped fracture network. The results also indicate that significant tracer mixing occured within the fracture network, a potential indicator of fracture complexity. All individually traced segments flowed back simultaneously, albeit at varying tracer concentrations. The residence time calculation for each tracer showed that frac fluid injected into the later proppant segments generally flowed back faster than the earlier segments. No obvious piston-like displacement of frac fluid was observed from the tracer data.
The Role of Microemulsion and Shut-in on Well Performance: From Field Scale to Laboratory Scale
Authors: Soleiman Asl Taregh , Habibi Ali , Ezulike Obinna Daniel , Eghbalvala Maryam , Dehghanpour Hassan
Published: January 2019

We analyzed flowback and post-flowback production data from a horizontal well in the Montney Formation, which was fractured with water containing a microemulsion additive. This well was shut-in for 7 months after 5 months of post-flowback production. Oil and gas rates were significantly increased after the shut-in (700% increase), suggesting a reduction in matrix-fracture damage. We performed imbibition oil-recovery tests to evaluate the imbibition of the ME solution into the oil-saturated core plugs. The results show that the microemulsion solution can spontaneously imbibe into the oil-saturated core plugs leading to the final oil recovery factor of 24% of the original oil in place, compared with the tap water case with only 2% oil recovery factor. Combined analyses of the field and laboratory results suggest that imbibition of the fracturing water containing the ME solution during the extended shut-in period leads to 1) reduction of water blockage near the fracture face and 2) counter-current production of oil. These two effects can explain the enhanced production rate of oil and gas after the shut-in period.
Proppant Transport and Behavior in Horizontal Wellbores Using Low Viscosity Fluids
Authors: Ahmad Faraj A. , Miskimins Jennifer L.
Published: January 2019

One of the most significant components of hydraulic fracturing modeling is the prediction of proppant transport in both the wellbore and fractures, as the resulting conductivity has a great impact on post treatment production. In multistage horizontal well treatments, the distribution of proppant between multiple perforation clusters has a substantial impact on treatment behaviors and results. If the proppant is not evenly distributed between the perforation clusters, the perforated intervals will not be equally stimulated. Only a few studies evaluating proppant transport in horizontal wellbores are found in the literature. This paper aims to investigate the parameters that have a large influence on the proppant settling in the wellbore and distribution of the proppants between perforation clusters, as well as providing insight into post-treatment flowback behaviors.

The approach to this work uses a model of a horizontal wellbore with three perforation clusters at shot densities of 4 SPF with 90-degree phasing. Fresh water was used as a carrier fluid to transport the proppant in the horizontal pipe. Two different types of proppants, sand and ultra-light-weight ceramic, of varying mesh sizes were used. Two design parameters, injection rate and proppant concentration, have been varied throughout the experimental tests.

The results from this work demonstrate that proppant settling velocity in the wellbore is different for each type of proppant. These differences are mainly due to the changes in the proppant concentration as well as the changes in the size and shape of proppant particles. The uneven proppant distribution between perforation clusters was mostly observed in cases where the density of proppnat was relatively high and at low flow rates. However, at high flow rates, the toe cluster received the largest amount of proppant. This occurs because the high flow rates near the first and second clusters prevent the proppant particles from turning into the perforation tunnels. The ultra-light weight ceramic shows the most even distribution between the perforation clusters since the density difference between the carrier fluid and the proppant particle is relatively low. The most significant finding is that the low viscosity fluid (fresh water) is not an effective transport system for larger particles with relatively high densities.

The results obtained from this study can be used to improve the understanding of good practices of fracture stimulation flushing, as well as proppant distribution/deposition throughout the horizontal pipe during the fracture stimulation treatment and during flowback processes.
Nanotechnology for water purification: electrospun nanofibrous membrane in water and wastewater treatment
Authors: Tlili I. , Alkanhal Tawfeeq Abdullah
Published: January 2019

The need for beneficial innovations in filtration expertise has lead to little consideration of cutting-edge materials, such as nanofiber membranes for water distillation. The presence of organic matter and traces of organics accumulation in wastewater poses a major problem and current technologies such as coagulation/flocculation and chlorine technology are unable to yield satisfying results. The extra volume of sludge generated by these technologies needs further processing and disposal. Nanotechnology has outstanding potential for filtration applications due to its capability to create precise structural controlled materials for such requirements. Electrospun nanofibrous membranes (ENMs) are cutting edge membrane technology that offer substantial high flux and high rejection rates compared to conventional membranes. ENMs present a revolution in water and sewage purification by offering a lightweight, cost-effective, and lower energy consumption process compared with conventional membranes. ENMs possess high porosity, generally approximately 80%, while conventional membranes have 5–35% porosity. Nano-engineered membranes have great potential in water treatment due to their exotic properties. In this connection, electrospinning membranes are emerging as a versatile technique with promising features for water treatment. This work highlights the application of ENM in wastewater treatment and surface modification of nanomembranes in order to address fouling issues and wastewater treatment from Tabuk Sewage Treatment Plant, Saudi Arabia.
Perception welfare assessment of water reuse in competitive categories
Authors: Zabala José A. , Dolores de Miguel Mª , Martínez-Paz José M. , Alcon Francisco
Published: January 2019

The supply of reclaimed water to ecosystems increases their ecosystem service flows, which is directly translated into terms of social welfare. This study explores the factors that determine the different perceptions of the welfare impact of supplying reclaimed water to different, and competitive, ecosystems in the Segura River Basin (southern Spain): specifically, an agroecosystem (agricultural irrigation) and a river (higher river flow). The results of a contingent valuation exercise with the population of the Murcia Region show four different groups of respondents, depending on their willingness to pay (WTP) preferences. The factors that identify differences among welfare impacts are the age, the gender, the education level, the monthly income, the nearness of the household to the river, and, above all, the degree of satisfaction with funding of water reclamation. This study broadens our knowledge of individuals' heterogeneous preferences in water reuse options, which is crucial for policy makers in the development of socially accepted and sustainable water resource management strategies.
Calibration and field application of a molecularly imprinted membrane-passive sampler for the sampling of indicator polychlorinated biphenyls in selected aquatic environments of South Africa
Authors: Mkhize Dennis S. , Quinn Laura P. , Nyoni Hlengilizwe , Mamba Bhekie B. , Msagati Titus A. M.
Published: January 2019

A passive sampling device, based on molecularly imprinted membranes (MIM), was fabricated and optimised for sampling polychlorinated biphenyls (PCBs) in aquatic ecosystems. The newly-developed passive sampler was subjected to in-situ calibration studies to determine PCB sampling rates under various conditions of water turbulence and temperature. This was carried out by exposing the passive samplers to water spiked with PCBs in a continuous-flow exposure setup. The samplers were preloaded with known concentrations of performance reference compounds (PRCs) prior to exposure. Sampling rates of seven indicator PCBs' congeners (PCBs 28, 52, 101, 118, 138, 153 and 180) ranged between 15.3 and 95.6 L/d for the different environmental conditions investigated. To determine the field suitability, the samplers were preloaded with PRCs and deployed for 10 days at the Roodeplaat and Hartbeespoort Dams, in South Africa. Water samples were taken at the end of the deployment period to compare the spot-and-grab samples to the developed samplers. PCBs 28, 101 and 138 were detected in the samplers deployed at Hartbeespoort Dam. The samplers deployed at the Roodeplaat Dam had quantifiable amounts of PCBs 28, 52, 101, 138 and 180 (0.047–0.828 ng mL−1 d−1). The sampler enhanced the detectability of PCB 52 and PCB 180, which were not detected in water samples. The field suitability trials indicated that the developed sampler could successfully be used for PCB monitoring. The sampler enhanced the detection of PCBs that would otherwise be too low to detect in samples collected through the traditional spot-and-grab sampling technique.
Diversidad e interculturalidad: La escuela indígena en contextos de migración
Authors: Velasco Ortiz Laura , Rentería Daniela
Published: January 2019

El objetivo del artículo es describir y analizar la diversidad cultural en escuelas indígenas y los retos de la interculturalidad frente a la discriminación étnico-racial. Metodológicamente, el artículo se basa en una encuesta sobre diversidad cultural a una muestra de 14 escuelas y en 21 grupos focales, con alumnado y docentes de las 70 escuelas del sistema de educación indígena en Baja California. Los hallazgos señalan una diversidad cultural escolar alimentada por los mismos elementos que surgen como objetos de discriminación étnico-racial  y migrante como base de la construcción inferiorizada de la categoría indígena —migrante y nativo—, en torno a la práctica de alguna lengua indígena, el color de la piel y su ancestralidad. Algunas limitaciones del artículo provienen de su atención a la población del alumnado y aunque considera la interacción docente, no analiza la diversidad de ese actor en el espacio escolar.
Accelerated Wound Healing Induced by a Novel Amphibian Peptide (OA-FF10)
Authors: Liu Naixin , Li Zhe , Meng Buliang , Bian Wenxin , Li Xiaojie , Wang Siyuan , Cao Xiaoqing , Song Yongli , Yang Meifeng , Wang Ying , Tang Jing , Yang Xinwang
Published: January 2019

Background:

Despite the continued development of modern medicine, chronic wounds
are still a critical issue in clinical treatment, placing a great physiological, psychological, and financial
burden on patients. Researchers have investigated many methods to solve this problem, with
bioactive peptides gaining increasing attention due to their considerable advantages and diverse
functions, as well as low cost, simple storage, and easy transportation.

Methods:

In this research, a novel peptide (named OA-FF10) was identified from the skin secretions
of the odorous frog species Odorrana andersonii. The sequence of mature OA-FF10 was
“FFTTSCRSGC”, which was produced by the post-translational processing of a 61-residue prepropeptide.

Results:

Similar to most frog peptides, OA-FF10 showed an intramolecular disulfide bridge at the
C-terminus. OA-FF10 demonstrated no antibacterial, antioxidant, hemolytic, or acute toxic activity,
but promoted wound healing and proliferation of human keratinocytes (HaCaT) both time- and
dose-dependently. Furthermore, while OA-FF10 had no effect on wound healing of Human Skin
Fibroblasts (HSF), it did accelerate healing in a full-thickness skin-wound mouse model.

Conclusion:

Our research revealed the strong wound-healing activity of OA-FF10 in vivo and in
vitro, thus providing a new candidate for the development of novel wound-healing drugs.
The Underlying Regulated Mechanisms of Adipose Differentiation and Apoptosis of Breast Cells after Weaning
Authors: Gao Weihang , Gao Zhao , Pu Shuqi , Dong Yanbin , Xu Xiaowen , Yang Xingping , Zhang Yuan , Fang Kui , Li Jie , Yu Weijian , Sun Nannan , Hu Ling , Xu Qin , Cheng Zhibin , Gao Yong
Published: January 2019

Numerous experimental studies have demonstrated that a series of remodeling processes occurred in the adipose tissue during the weaning, such as differentiation. Fibroblasts in the breast at weaning stage could re-differentiate into mature adipocytes. Many transcriptional factors were involved in these processes, especially the PPARγ, C/EBP, and SREBP1. There is cell apoptosis participating in the breast tissue degeneration and secretory epithelial cells loss during weaning. In addition, hormones, especially the estrogen and pituitary hormone, play a vital role in the whole reproductive processes. In this review, we mainly focus on the underlying regulated mechanisms of differentiation of adipose tissue and apoptosis of breast cell to provide a specific insight into the physiological changes during weaning.
Intrauterine Growth Restriction Alters the Genome-Wide DNA Methylation Profiles in Small Intestine, Liver and Longissimus Dorsi Muscle of Newborn Piglets
Authors: Tao Shiyu , Zhou Tianjiao , Saelao Perot , Wang Ying , Zhu Yuhua , Li Tiantian , Zhou Huaijun , Wang Junjun
Published: January 2019

Intrauterine growth restriction (IUGR) remains a major problem in swine production since the associated low birth weight leads to high rates of pre-weaning morbidity and mortality, and permanent retardation of growth and development. The underlying regulatory mechanisms from the aspects of epigenetic modification has received widespread attention. Studies explore the changes in genome wide methylation in small intestine (SI), liver and longissimus dorsi muscle (LDM) between IUGR and normal birth weight (NBW) newborn piglets using a methylated DNA immunoprecipitation-sequencing (MeDIP-Seq) approach. The data demonstrated that methylated peaks were prominently distributed in distal intergenic regions and the quantities of peaks in IUGR piglets were more than that of NBW piglets. IUGR piglets had relatively high methylated level in promoters, introns and coding exons in all the three tissues. Through KEGG pathway analysis of differentially methylated genes found that 33, 54 and 5 differentially methylated genes in small intestine, liver and longissimus dorsi muscle between NBW and IUGR piglets, respectively, which are related to development and differentiation, carbohydrate and energy metabolism, lipid metabolism, protein turnover, immune response, detoxification, oxidative stress and apoptosis pathway. The objective of this review is to assess the impact of differentially methylation status on developmental delay, metabolic disorders and immune deficiency of IUGR piglets.
Tight Junction Proteins in the Weaned Piglet Intestine: Roles and Regulation
Authors: Wang Jing , Ji Haifeng
Published: January 2019

The intestinal epithelial barrier plays a crucial role in the health and growth of weaned piglets. Proper epithelial function mainly depends on tight junctions (TJs), which act as both ion channels and a barrier against noxious molecules. TJs are multiprotein complexes consisting of transmembrane and membrane-associated proteins. Because the intestine in piglets is immature and incomplete, its structure and function are easily impaired by various stresses, infections, and food-related factors. Certain nutrients have been demonstrated to participate in intestinal TJ regulation. Probiotics, amino acids, fibers, oligosaccharide, and certain micronutrients can enhance barrier integrity and counteract infections through elevated TJ protein expression and distribution. In this review, the distribution and classification of intestinal TJs is described, the factors influencing TJs after weaning are summarized, and the regulation of weaning piglet intestinal TJs by nutrients is discussed.
Advance in Tissue Differentiation and its Regulatory Mechanisms by Master Proteins of Nervous System during Weaning
Authors: Ma Wenyu , Tang Chengfang , Hu Huiling , Zhang Fenglian , Wang Xuanying , Wu Xiaoting , Zhang Wenjian , Wang Xiaoxia , Ma Huazhi , Li Zhihao , Dong Yanbin , Yang Zehong , Feng Shixiu , Tian Liping , Gao Yong
Published: January 2019

Weaning is a critical period for the growth and development of mammals, in which various physiological and biochemical indicators of the body have undergone great changes. The development, differentiation, and maturation of the nervous system are regulated by many proteins. Changes in related proteins affect the physiological functions of the nervous system. However, the regulation of selfrenewal and differentiation of the nervous system at this stage is still poorly understood. The mechanism of differentiation and regulation of the major proteins in the nervous system during this special period of weaning remains to be investigated. Therefore, this paper aims to summarize the alteration of the nervous system during weaning and provide the basis for subsequent research.
Differentiation and Proliferation of Intestinal Stem Cells and its Underlying Regulated Mechanisms during Weaning
Authors: Chen Xi , Yang Zehong , Hu Huiling , Duan Wentao , Wang Aiping , Dong Yanbin , Gao Weihang , Deng Song , Cheng Bo , Li Jiali , Sun Nannan , Cheng Zhibin , Guo Wenfeng , Li Yanwu , Gao Yong
Published: January 2019

Weaning is a stressful event associated with gastrointestinal disorders and increased disease
susceptibility. Many studies have reported the changes that happened in the gut of various mammals such
as pigs and rats after weaning. These findings suggest that the development of intestinal tract mainly is
affected at the time of weaning through interfering in the differentiation and proliferation of intestinal
stem cells. Weaning stress stimulates the rapid differentiation and proliferation of intestinal stem cells in
order to adjust to changes caused by weaning, which are mainly manifested as deeper crypt depth and
decreased intestine villus height. However, the accelerated cellular process may lead to an increase in
the proportion of immature intestinal epithelial cells and goblet cells, which affect intestinal permeability
and reduce the gut-barrier function against toxins and pathogens. This review briefly describes the effects
coforticotrophin-releasing factor (CRF), epidermal growth factor (EGF) and polyamines on the differentiation
and proliferation of intestinal stem cells after weaning and discusses its possible underlying regulatory
mechanisms. Firstly, weaning stress activates CRF to binds its receptors, which induces proinflammatory
responses and promote rapid differentiation and proliferation of intestinal stem cells to a
larger fraction of immature intestinal epithelial cells and goblet cells. Secondly, the lack of EGF after
weaning inhibits the expression of goblet cell maturation factors and makes it difficult for goblet cells
and intestinal epithelial cells to mature. Finally, diet and endogenous synthesis lead to excessive polyamines
in the intestine, which promote the proliferation of intestinal stem cells by regulating the expression
of human antigen R (HuR) and other related genes at the time of weaning.
Effects of Dietary L-arginine Supplementation from Conception to Post- Weaning in Piglets
Authors: Che Dongsheng , Adams Seidu , Zhao Bao , Qin Guixin , Jiang Hailong
Published: January 2019

Weaned piglets experience sudden changes in their dietary patterns such as withdrawal from the easily digestible watery milk to a coarse cereal diet with both systemic and intestinal disruptions coupling with the expression of pro-inflammatory proteins which affects the immune system and the concentrations of haptoglobin including both positive and negative acute-phase proteins in the plasma. L-arginine is an important protein amino acid for piglets, but its inadequate synthesis is a nutritional problem for both sows and piglets. Recent studies indicated that dietary supplementation of L-arginine increased feed intake, uterine growth, placental growth and nutrient transport, maternal growth and health, embryonic survival, piglets birth weight, piglet’s growth, and productivity, and decreased stillbirths. L-arginine is essential in several important pathways involved in the growth and development of piglets such as nitric oxide synthesis, energy metabolism, polyamine synthesis, cellular protein production and muscle accretion, and the synthesis of other functional amino acids. However, the underlying molecular mechanism in these key pathways remains largely unresolved. This review was conducted on the general hypothesis that L-arginine increased the growth and survival of post-weaning piglets. We discussed the effects of dietary L-arginine supplementation during gestation, parturition, lactation, weaning, and post-weaning in pigs as each of these stages influences the health and survival of sows and their progenies. Therefore, the aim of this review was to discuss through a logical approach the effects of L-arginine supplementation on piglet’s growth and survival from conception to postweaning.
MicroRNA Determines the Fate of Intestinal Epithelial Cell Differentiation and Regulates Intestinal Diseases
Authors: Ding Sujuan , Liu Gang , Jiang Hongmei , Fang Jun
Published: January 2019

The rapid self-renewal of intestinal epithelial cells enhances intestinal function, promotes the nutritional needs of animals and strengthens intestinal barrier function to resist the invasion of foreign pathogens. MicroRNAs (miRNAs) are a class of short-chain, non-coding RNAs that regulate stem cell proliferation and differentiation by down-regulating hundreds of conserved target genes after transcription via seed pairing to the 3' untranslated regions. Numerous studies have shown that miRNAs can improve intestinal function by participating in the proliferation and differentiation of different cell populations in the intestine. In addition, miRNAs also contribute to disease regulation and therefore not only play a vital role in the gastrointestinal disease management but also act as blood or tissue biomarkers of disease. As changes to the levels of miRNAs can change cell fates, miRNA-mediated gene regulation can be used to update therapeutic strategies and approaches to disease treatment.
Kinase Targets for Mycolic Acid Biosynthesis in Mycobacterium tuberculosis
Authors: Alsayed Shahinda S.R. , Beh Chau C. , Foster Neil R. , Payne Alan D. , Yu Yu , Gunosewoyo Hendra
Published: January 2019

Background:

Mycolic acids (MAs) are the characteristic, integral building blocks for the mycomembrane belonging to the insidious bacterial pathogen Mycobacterium tuberculosis (M.tb). These C60-C90 long α-alkyl-β-hydroxylated fatty acids provide protection to the tubercle bacilli against the outside threats, thus allowing its survival, virulence and resistance to the current antibacterial agents. In the post-genomic era, progress has been made towards understanding the crucial enzymatic machineries involved in the biosynthesis of MAs in M.tb. However, gaps still remain in the exact role of the phosphorylation and dephosphorylation of regulatory mechanisms within these systems. To date, a total of 11 serine-threonine protein kinases (STPKs) are found in M.tb. Most enzymes implicated in the MAs synthesis were found to be phosphorylated in vitro and/or in vivo. For instance, phosphorylation of KasA, KasB, mtFabH, InhA, MabA, and FadD32 downregulated their enzymatic activity, while phosphorylation of VirS increased its enzymatic activity. These observations suggest that the kinases and phosphatases system could play a role in M.tb adaptive responses and survival mechanisms in the human host. As the mycobacterial STPKs do not share a high sequence homology to the human’s, there have been some early drug discovery efforts towards developing potent and selective inhibitors.

Objective:

Recent updates to the kinases and phosphatases involved in the regulation of MAs biosynthesis will be presented in this mini-review, including their known small molecule inhibitors.

Conclusion:

Mycobacterial kinases and phosphatases involved in the MAs regulation may serve as a useful avenue for antitubercular therapy.
Alinhamentos Parafrásticos PE--PB de Construções de Predicados Verbais com o Pronome Clítico lhe
Authors: Rebelo-Arnold Ida , Barreiro Anabela Marques , Quaresma Paulo , Mota Cristina
Published: January 2019

Este artigo apresenta o alinhamento de construções contendo predicados verbais com o clítico lhe nas variedades de Português Europeu (PE) e Português do Brasil (PB), como nas frases Já lhe arrumaram a bagagem --- Sua bagagem está seguramente guardada, onde a próclise do dativo lhe em PE contrasta com o pronome possessivo sua em PB. Selecionámos vários pares contrastivos de paráfrases, tais como pronomes clíticos em próclise e ênclise, pronomes ocorrendo em presença de pronomes relativos e de advérbios de negação, entre outras construções a fim de ilustrar esse fenómeno linguístico. Algumas diferenças correspondem a contrastes reais entre as duas variedades de Português, enquanto que outras representam escolhas puramente estilísticas. As variantes contrastivas foram alinhadas manualmente a fim de estabelecer um conjunto padrão, e a tipologia estabelecida de forma a poder ser futuramente ampliada e disponibilizada ao público. Os alinhamentos dos pares de paráfrases foram executados no corpus e-PACT usando a ferramenta CLUE-Aligner. Esta pesquisa foi desenvolvida no âmbito do projeto eSPERTo.
Asociación Mexicana de Enfermeras Especializadas en Medicina Crítica y Terapia Intensiva. A.M.E.E.M.C.T.I, A.C.
Authors: López Rosales Ma. De los Angeles
Published: January 2019

La Asociación Mexicana de Enfermeras Especializadas en Medicina Crítica y Terapia Intensiva (A.M.E.E.M.C.T.I.A.C.) es una organización gremial de profesionales de Enfermería que ejercen la atención y cuidados especializados para el enfermo grave. Esta Asociación ha contribuido con ahínco en el desarrollo profesional de sus integrantes a las nuevas generaciones de Enfermeras a sumarse a esta agrupación para fortalecer su desarrollo personal y profesional.

El 14 de septiembre de 1977 se obtuvo el permiso de la Secretaría de Relaciones Exteriores para constituir la Asociación, Asociación Mexicana de Enfermeras Especializadas en Medicina Crítica y Terapia Intensiva cuya visión es la promoción del desarrollo profesional de sus agremiados a través de diversas actividades académicas de calidad con profesionales expertos en la atención del paciente grave. Para cumplir con esta visión la Asociación tiene los siguientes objetivos, entre otros: Agrupar a las Enfermeras interesadas que dentro de su especialidad, lleven a cabo de manera preferente o exclusiva, trabajos relacionados con el cuidado intensivo del enfermo en estado grave.

Fomentar y difundir el estudio de la Enfermería en Terapia Intensiva. Organizar congresos, conferencias, mesas redondas, seminarios y otras actividades académicas sobre puntos de interés relativos a la especialidad.

La Asociación cuenta con 5 filiales en : Tamaulipas, Baja California, Nuevo León Tabasco y Veracruz.
Hacia una perspectiva de género en la evaluación de la calidad de la atención en los servicios de salud reproductiva
Authors: Torres Lagunas María De los Ángeles
Published: January 2019

La necesidad de integrar la perspectiva de género en las políticas y programas gubernamentales de nuestro país, ha sido reconocida a partir de los compromisos acordados en la Conferencia Internacional sobre Población y Desarrollo efectuada en El Cairo (1994) Y de la Cuarta Conferencia Internacional de la Mujer celebrada en Pekín (1995), de las cuales han derivado recomendaciones por parte de Organización Mundial de la Salud (OMS) y de la Organización Panamericana de la Salud (OPS) a los países miembros, para que estos se comprometan a reconocer y corregir las inequidades de género que vulneran el ejercicio del derecho a la salud entre los habitantes de los Estados Miembros, apoyados en tres pilares conceptuales: equidad, género y participación democrática.

En México existen pocas investigaciones que evalúan la calidad de la atención en los servicios de salud sexual y reproductiva desde la perspectiva de género. Por lo tanto, es necesario realizar nuevos estudios con este enfoque e implementar nuevas formas de evaluar la calidad de la atención en estos servicios, que incluyan indicadores construidos desde la perspectiva de género, que consideren metodologías cualitativas, que superen el carácter administrativo y normativa centrado en la estructura y en los resultados y que su orientación no solamente tenga que ver con metas demográficas relativas a la efectividad en el uso de métodos anticonceptivos y en niveles de fecundidad alcanzados. Estrategias evaluativas más humanas que analicen la dimensión social de la calidad desde el ejercicio del derecho a la salud en lo general y de los derechos sexuales y reproductivos en lo particular considerando a la persona como un ser integral.
El Holismo un nuevo paradigma de la ciencia Enfermera
Authors: Rodríguez Jiménez Sofía , Sotomayor Sánchez Sandra
Published: January 2019

El conocimiento de la Enfermería requiere hoy en día, de una clara definición en sus teorías y conceptos que fundamenten la ciencia del cuidado, tanto para la investigación, la formación y la práctica. Este trabajo propone analizar el cuidado holístico como paradigma científico, lo cual tiene gran importancia para la construcción disciplinar y la consolidación de la identidad profesional.

EI holismo se inscribe en el paradigma de la fenomenología critica por las características de las ciencias humanístico sociales, esta consideración permite dar respuesta a nuevas interpretaciones de la realidad, se parte de la consideración de que la persona es un todo integrado, al reconocerle dimensiones psicosociales y culturales, biofisiológicas y espirituales. EI otorgar cuidado holístico en la actualidad, constituye en sí un compromiso ético profesional impostergable que las Enfermeras deberán considerar como parte fundamental para la formación académica y la práctica profesional.

La fenomenología critica como paradigma, privilegia la investigación integral, en donde se valora la comprensión de los lenguajes de las personas, grupos y comunidades, los significados que le asignan a sus experiencias de salud y de vida y para ello es necesario indagar en las creencias y valores de cada grupo social y poder construir el constructo "cuidado humane de la Enfermería". Es meta deseable que las Enfermeras incursionen en la investigación de este fenómeno que logre rescatar los valores que caracterizan la cultura de los colectivos humanos en sus contextos específicos y que les han permitido resolver problemas de salud, y que son relevantes en la fundamentación de la naturaleza del cuidado.
Aprendizajes que promueve el Plan Único de Especialización en Enfermería.
Authors: Piña Jiménez Irma , Balán Gleaves Cristina , Rodríguez Méndez Amelia , Vázquez López Graciela
Published: January 2019

Introducción, identificar los aprendizajes que las alumnas adquieren en su trayecto de formación como enfermeras especialistas, es una manera de reconocer el impacto que tienen los procesos de formación de recursos humanos que se llevan a cabo a través del Plan Único de Especialización en Enfermería (PUEE). Objetivo, Identificar los aprendizajes que se consolidan en los alumnos que transitan por el PUEE, en sus diversas ramas a su egreso. Metodología, estudio descriptivo longitudinal que abarca tres cohortes generacionales de alumnos – 2006, 2007 y 2008- que cursaron alguna especialidad de enfermería dentro del PUEE. Se aplicó un cuestionario de preguntas abiertas, con carácter anónimo en el que se interrogó a los alumnos, sobre los principales conocimientos y habilidades que fueron desarrollados en la especialidad, las bondades y debilidades que estuvieron presentes en las sedes de prácticas y la recomendación del estudio de la especialidad a sus conocidos. Resultados se presentan cuadros que concentran las respuestas de mayor frecuencia, considerando los rubros mencionados. Discusión los resultados muestran en todos los casos puntos de encuentro a los largo de las tres generaciones, respecto a los conocimientos y habilidades que fueron adquiridos. Los aprendizajes señalados se vinculan con los propósitos curriculares del PUEE. Conclusiones. La presencia de aprendizajes específicos que son significativos para alguna cohorte generacional en particular, puede explicarse como aspectos sobre los que los tutores y docentes, así como la sede de prácticas, tuvieron oportunidad de hacer énfasis en la generación en turno.