bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of metabolic effects of del Nido cardioplegia, blood cardioplegia, and St. Thomas cardioplegia solutions in adult patients undergoing isolated minimally invasive aortic valve replacement surgery
Authors: LAFÇI Ayşe , GOKCİNAR Derya , BUDAK Ali Baran , DAG Osman , McCusker Kevin , GÜNAYDİN Serdar
Published: November 2018

Aim: Cardiac arrest during cardiopulmonary bypass (CPBP) is achieved using cardioplegia solutions for myocardial protection. There are limited data about the systemic biochemical effects of cardioplegia solutions. This study aimed to compare the biochemical effects of del Nido cardioplegia, blood cardioplegia, and St. Thomas cardioplegia solutions.Material and Methods: This retrospective study included patients that underwent isolated Aortic valve replacement between 1 August 2017 and 31 July 2018. The medical records of patients reviewed after ethical approval of the protocol. Patients were divided into 3 groups according to the cardioplegia solution used during surgery, as follows: the del Nido cardioplegia group (dNC group); the blood cardioplegia group (BC group); the St. Thomas cardioplegia group (STC group). Perioperative clinical outcomes and laboratory findings were compared between groups. Results: The study included 26 patients that underwent minimally invasive aortic valve replacement. Fewer patients in the dNC group required inotropic agents than in the other 2 groups, but the difference was not significant (P = 0.844). There wasn’t a significant difference between the groups in the change in the troponin t level from the preoperative to postoperative period (P = 0.148). The difference in the arterial glucose and insulin levels was similar in all 3 groups (P = 0.372 and P = 0.258, respectively). Thyroid, liver, and renal function were also similar in all 3 groups. Conclusion: dNC solution is a safe alternative to BC and STC solutions during isolated minimally invasive aortic valve replacement surgery, in terms of myocardial protection and biochemical parameters.
Intergenerational Caregivers of Parents With End-Stage Heart Failure
Authors: Alonso Windy Williams , Kitko Lisa A. , Hupcey Judith E.
Published: November 2018

Purpose:The purpose of this study was to longitudinally explore the experiences of young adult, adult, and older adult intergenerational caregivers caring for a parent with end-stage heart failure (HF).Design:This study was a secondary analysis of qualitative data collected during a longitudinal study that sought to determine the palliative care needs of individuals with end-stage HF and their family caregivers.Methods:Longitudinal interviews from 23 young adult, adult, and older adult children who were caring for a parent with end-stage HF were selected for thematic analysis. Researchers individually analyzed the interviews and then, as a group, came to a consensus about themes.Findings:Five major themes were identified: caregiver resources, role management, caregiver–parent relationships, filial responsibility, andpersonal benefits and challenges.Conclusions:These intergenerational caregivers struggled to balance their busy lives and caregiving roles. However, most felt supported by other family members or external resources. Longitudinal findings support a need for improved employer-based support for intergenerational caregivers and special attention to young carers in research and practice. Recognition of and advocacy for intergenerational caregivers providing care for a chronically ill parent is needed.
Educação infantil e currículo: Uma Análise da proposta da rede municipal de Curitiba/PR
Authors: Ens Romilda Teodora , Nagel Jaqueline Salanek de Oliveira , Bueno Édina Dayane de Lara
Published: November 2018

O presente artigo apresenta uma reflexão acerca do documento “Educação Infantil: Caderno I – princípios e fundamentos” da Rede Municipal de Ensino de Curitiba (RMEC), que norteia o currículo da Educação Infantil no município. A pesquisa buscou verificar a relação entre o documento da RMEC com a versão final da Base Nacional Curricular Comum (BNCC) e as Diretrizes Curriculares para a Educação Infantil (DCNEI) no que diz respeito ao currículo e ao processo de avaliação, bem como analisar como são sugeridas essas práticas na RMEC. O suporte da análise crítica do discurso de Fairclough (2001. 2012) e “Decifrar textos para compreender a política: subsídios teórico-metodológicos para análise de documentos” de Shiroma, Campos e Garcia (2005) subsidiaram esta pesquisa documental, possibilitando inferir que o documento que contempla a proposta de Educação Infantil para a Rede Municipal de Ensino de Curitiba assegura as especificidades para essa modalidade de ensino. A construção do documento que norteia a RMEC foi coletiva, expondo a concepção de currículo e avaliação na Educação Infantil defendida, além de propor a organização e estruturação para que se efetive um trabalho nas escolas e centro de educação infantil desse município.
Well-Collision-Avoidance Management and Principles
Authors: Sawaryn S. J. , Wilson H.. , Allen W. T. , Clark P. J. , Mitchell I.. , Codling J.. , Sentance A.. , Poedjono B.. , Lowdon R.. , Bang J.. , Nyrnes E..
Published: November 2018

The well-collision-avoidance management and principles presented in this paper are a culmination of the work and consensus of industry experts from both operators and service companies in the SPE Wellbore Positioning Technical Section (WPTS). This is not a new subject, but current guidance is disparate, company-specific, and occasionally contradictory. As a result, the guidance can be difficult to understand and implement. A further aim is to drive the standardization of the well-collision-avoidance rules, process, and nomenclature throughout the industry. Standardization improves efficiency and reduces implementation errors.

The consequences of an unplanned intersection with an existing well can range from financial loss to a catastrophic blowout and loss of life. The process of well-collision avoidance involves rules that determine the allowable well separation, the management of the associated directional planning and surveying activities, and assurance and verification. The adoption of a specific minimum-allowable separation rule, no matter how conservative, does not ensure an acceptably low probability of collision. Many other factors contribute, such as the level of compliance by office and rig personnel with collision-avoidance procedures, and the completeness and correctness of the directional database. All these factors are connected.

The material is split into eight sections, each dealing with a critical element in the collision-avoidance process. Examples are presented to highlight a good-implementation practice. This aligned approach will dispel some of the current confusion in the industry concerning well-collision avoidance; will improve efficiency when planning and executing wells; and will build industry focus on the associated collision risks when drilling. The WPTS is also supporting the current development of API RP 78 (not yet issued).

This is the first of two papers. The second paper (Sawaryn et al. 2018) covers the minimum-allowable separation rule and its application, assurance, and verification.
Impact of Anisotropic Stresses on the Slotted Liners Performance in Steam Assisted Gravity Drainage Process
Authors: Wang Chenxi , Pang Yu , Montero Jesus , Haftani Mohammad , Fattahpour Vahidoddin , Mahmoudi Mahdi , Nouri Alireza
Published: November 2018

Thermal stimulation techniques are widely used to exploit Western Canadian heavy oil assets. These techniques rely on injection of steam into the formation, inducing complex geomechanical stresses in the reservoir and surrounding strata during the life cycle of the project. In SAGD wells, the collapsed oil sand around the liner undergoes a stress buildup which causes gradual sand compaction. The stress buildup is influenced by several factors such as the in-situ stresses, reservoir poroelastic and thermal expansion, and reservoir shear dilation. However, the impact of stress level and anisotropy around the liner is not properly accounted for in previous research on slotted liner design. This paper investigates the effect of anisotropic stress buildup around slotted liners on their sanding and plugging performance under multiphase flow conditions.

A Scaled Completion Testing (SCT) facility was utilized to emulate multi-axial stress and multiphase flow conditions near the sand control liner. Brine, oil, and gas were used as flowing fluids. Sand-pack samples were prepared using commercial sands by matching the particle size, shape and, composition of the McMurray Formation oil sands. A constant lateral stress and several axial stresses were applied to simulate the stress conditions around the liner. The three-phase flow condition was used to evaluate the role of the steam breakthrough on the liner performance.

Experimental results indicate the critical role of stress conditions around the liner on its sanding and plugging responses. Results show gradual sand-pack compaction with the gradual increase of the axial stress. Higher axial stresses result in a smaller amount of produced sand, which can be attributed to the stronger inter-particle frictional resistance, hence, stronger and more stable sand bridges behind the slots. The higher compaction results in a lower porosity and permeability, hence, altering the plugging and sanding response of the liner. Also, higher retained permeabilities are found for stronger anisotropic stress conditions. Besides, it is found that the three-phase flow condition could cause a stronger fines migration and production, compared to single-phase flow.

The results of this study indicate that the stress and multiphase flow effects are crucial factors in the evaluation of slotted liner performance. The findings from the innovative experimental studies provide insights into the practicability of evaluating slotted liner performance with the consideration of sophisticated field conditions and optimizing the selection of the slotted liner aperture for the entire well lifespan.
Addressing Thermal Loading Uncertainties for Liner Design
Authors: Chartier Mark A. , Miller Samantha M. , Kaiser Trent M.
Published: November 2018

Liners in the unconsolidated sand reservoirs common to SAGD applications are subjected to a unique combination of loads that arise due to re-established formation stresses combined with large temperature changes. Temperature changes that occur following frictional constraint of the liner induce axial strain that can yield the liner, which reduces its capacity to resist ovalisation under non-uniform re-established formation stresses. These types of liner deformations are undesirable because they can restrict wellbore access, compromise other liner functions (e.g., sand or inflow control) or, in the worst case, drive a complete collapse failure.

The magnitude, non-uniformity, and evolution of re-established formation stresses present in SAGD wells remains highly uncertain. Consequently, many of the liner designs deployed in early wells relied on approximations of the re-established formation stresses, for example, from experimental testing and analytical approximations provided by van den Hoek et. al. (2000b).

Industry experience with liners deployed in thermal applications has been mixed. Some projects have indicated very low rates of liner failures. Conversely, other projects in the same formations, or in formations with similar characteristics, have experienced higher failure rates with measured liner ovalisations that suggest re-established formation stress (REFS) distributions can be more severe than previously assumed.

This paper describes how REFS impacts long-term integrity of thermal liners in unconsolidated sand reservoirs and how uncertainty in those stresses can be the difference between success and failure. The sensitivity of thermal liner structural performance of several common liner systems to re-established formation stresses is examined. The results align with field experience and highlight the importance of developing a strong understanding of the downhole loading environment to ensure liner designs promote long-term integrity and sustained production. The paper recommends several activities that will enable industry to more rigorously determine re-established formation stress and proposes refinements to the design and selection basis for liners deployed in thermal wells to manage the risk of deformations that result from thermal loading.
Visualization of Fines Migration in the Flow Entering Apertures through the Near-Wellbore Porous Media
Authors: Ansari Shadi , Yusuf Yishak , Kinsale Lisa , Sabbagh Reza , Nobes David S.
Published: November 2018

Various slotted liners geometries are used to control the sand production in SAGD operations. The geometry of a slot (shape and size) not only affect sand production but it may also influence fine deposition and scaling at the slot entrance. Failure of SAGD wells due to the deposition of particles is an important issue that needs to be investigated at the pore scale. This study provides a fundamental understanding of fines transport and the plugging potential at the entrance of the slots on slotted liners. Three slot profiles including straight shape, keystone shape and seamed (rolled top) shape are examined experimentally in relation to the preceding conditions of pore spaces in porous media. The potential of slot plugging is also studied from the fluid flow motion perspective. This task is achieved by visualization of the flow passing through the near well bore region of different slot geometries using an optical technique, namely, particle image velocimetry. Motion of small particles (D = 20μm) in the oil flow are captured before entering the slot, at the entrance and after leaving the slot entrance. The changes in the streamlines and velocities are analyzed to estimate the potential plugging locations. The results highlights how changing the entrance geometry of the slots may increase the deposition potential in and around a slot. The flow of the oil within the near wellbore porous media have also indicated that depending on the locations of the porous media within the flow structure, different deposition pattern may take place. Based on the result of this study it can be concluded that among the slots, keystone has the highest potential for the particle build up within and at the entrance of the slot.
Post Yield Strain Fatigue Experiments to Validate Low Cycle Methodology for Tubular and Connections
Authors: Krishna Shree , Milligan Ryan , George Ken , Krishnamurthy Ravi M. , Powers Jim , Krener III John
Published: November 2018

Post yield design methodology using Ductile Failure Damage Indicator (DFDI) for well tubulars was proposed and has been used for tubulars and connections life assessment. The tubular design assessment model incorporates a connection strain localization factor (SLF) to assess the fatigue life of the tubulars. Critical strain, a material-dependent parameter essential for DFDI, is obtained using the uniaxial stress-strain tests (i.e., strained to failure uniaxial tests). Understanding the impact of accumulated cyclic damage on critical strain is essential to the post-yield design approach. This paper aims to validate and evolve the low cycle methodology by 1) quantifying the effect of accumulating cyclic plastic strain on the critical strain through a series of post-yield axial and thermal strain fatigue experiments, and 2) applying the post-yield design approach to assess tubulars and connections.

Low cycle fatigue experiments demonstrating the critical strain measurement and its dependency on the thermal and axial-strain cycles will be discussed in the paper. Critical strain (K55 and L80) from monotonic tests is compared to critical strain obtained from cyclically preconditioned samples. Effect of cyclic plasticity on critical strain is established quantitatively. Coupons are also subjected to the post-yield axial and thermal cycles to failure and compared to critical strain-based DFDI design predictions. Since connections are known to be the weakest link in the casing system, the impact of connection thread-forms on the strain localization factor is demonstrated using a series of finite element models and the experimental material responses. Axial strain-controlled loading would be applied on the tubulars and connections to estimate the damage using the DFDI approach. A systematic approach to delineate the dependency of critical strain on cyclic straining validates the effectiveness of DFDI in thermal well design. Further, the quantification of SLF for integrating connection into thermal well design provides a complete solution.
SAGD Production Casing Failure Diagnosis and Repair
Authors: Plaxton Bill , Pehlke Trent , Baxter Dennis , Crockett Matt , Kaiser Trent
Published: November 2018

The operator experienced an unusual casing failure at a producing SAGD (steam assisted gravity drainage) oil well in summer of 2017. The subject well in the Firebag SAGD field of NE Alberta, Canada had operated successfully for over 11 years. Once the problem was identified, the well was shut in to determine the nature of the failure and options for repair and recovery so it could be returned to operation as soon as possible.

Tasks included identifying and isolating the failure, establishing the cause and nature of the failure, and determining viable repair options. Logging diagnostics to measure/image the failure were performed, which included new ultra-sonic logging imaging technology, high-resolution multi-finger caliper logging, a downhole camera run and conventional eddy flux casing inspection log. Historical log data was also reviewed to assess whether the failure evolved over time, or if the mechanism was acute. Once the nature of the failure was established, the optimal repair method was chosen, planned and carried out.

Sophisticated analysis of multi-finger caliper log data, camera images and new technology in the form of an ultrasonic imaging tool for the casing were utilized and are presented. A discussion of potential root cause mechanisms for thermal wells is provided, including a variety of failure modes that could be ruled out. Confidence in the failure mode specific to this well was increased by considering information acquired from multiple diagnostic tools. The nature of the connection failure determined from this process is outlined, along the rationale behind the repair method selected to remediate the well.
Increase Exposed Bitumen Reserves by Optimizing Wellbore Placement in Oil Sands with Extra-Deep Azimuthal Resistivity LWD Service
Authors: Vetsak Aleksandr , Jablonski Bryce
Published: November 2018

This paper describes a novel approach in drilling production wells while implementing real-time mapping of the Bitumen-Water Contact (BWC) with extra-deep azimuthal resistivity (EDAR) logging while drilling (LWD) service, thereby resulting in an increase of exploited bitumen reserves by optimizing wellbore placement. Within the Athabasca Bitumen Reservoir, the EDAR LWD service confidently mapped the BWC within a range of 2-22 meters below the entire producer wellbore. It also provided an earlier warning of an approaching low resistivity boundary, which allowed the operator to optimize the wellbore placement using real-time proactive steering decisions. In contrast to the existing azimuthal resistivity tools, which have the limited depth of investigation, this approach significantly mitigated the risks of intersecting or giving an incomplete picture of BWC surface. The real-time interpretation of extra-deep azimuthal resistivity data provided better understanding of the lateral distribution of the McMurray Formation along the horizontal wellbore, lithologically varying from clean sand facies to mud-filled channel facies and inclined heterolithic stratification (IHS) facies. The fluid heterogeneity of the reservoir included partial reservoir charging, irregular BWC and lean zones, which compounded lithology complexity within the reservoir. In one of the case studies, 50 percent increase was achieved in actual exploited bitumen reserves in comparison to the projected exploited reserves if drilled per the planned trajectory.

This new LWD approach was proven effective while drilling horizontal appraisal and producing wells in unconsolidated formations with high reservoir heterogeneity, it offered an opportunity to better understand the bitumen reservoir and ultimately led to increased production performance of Oil Sands projects.
Experimental Assessment of Wire-Wrapped Screens Performance in SAGD Production Wells
Authors: Montero Pallares Jesus David , Wang Chenxi , Haftani Mohammad , Pang Yu , Mahmoudi Mahdi , Fattahpour Vahidoddin , Nouri Alireza
Published: November 2018

This study presents an evaluation of Wire-Wrapped Screens (WWS) performance for SAGD production wells based on Pre-packed Sand Retention Testing (SRT). The impacts of features such as flow rates, water cut, steam-breakthrough events and fluid properties on flow performance and sand production are analyzed. The aim is to obtain a better understanding of WWS performance under several SAGD operational conditions for typical sand classes in the McMurray Formation in Western Canada.

The study employs a large pre-packed SRT to assess the performance of WWS with different aperture sizes and standard wire geometries. The testing plan includes sand samples with two representative particle size distributions (PSD's) and fines contents. Testing procedures were designed to capture typical field flow rates, water cut, and steam-breakthrough scenarios. The amount of sand production and pressure drop across the zone of the screen and adjacent sand were measured and used to assess the screen performance. Furthermore, fines production was measured to evaluate plugging tendencies and flow impairment during production.

The experimental results and data analysis show that aperture selection of WWS is dominated by their sand retention ability rather than the flow performance. The relatively high open flow area (OFA) makes WWS less prone to plugging. There is an increase in flow impairment after finalizing the injection scheme (oil+water+gas); however, it is controlled over the acceptable margins even with a narrow aperture. Further, a comparison of initial and final turbidity measurements showed that fines mobilization and production during single-phase brine flow was higher than in two-phase brine-oil flow at the same liquid flow rate. Excessive produced sand was observed for wider slots during the multi-phase (brine, oil, and gas) flow when gas was present, highlighting the impact of the breakthrough of wet steam on sand control performance. Flow impairment and pressure drop evolution were strongly related to the mobilization and accumulation of fines particles in the area close to the screen coupon; it is critical to allow the discharge of fines to maintain a high-retained permeability. Results also signify the importance of adopting adequate flow rates and production scenarios in the testing since variable water cuts and GORs showed to impact both sanding and flow performances.

This research incorporates both single-phase and multiphase flow testing to improve design criteria for wire-wrapped screens and provide an insight into their performance in thermal recovery projects. An improved post-mortem analysis includes fines production measurements to correlate these to the retained permeability caused by the pore plugging, which has hardly been evaluated in previous studies.
Peripartum Cardiomyopathy: A Case Report
Authors: Basaran Ozlem Ece , Guvendag guven Emine Seda , Guven Suleyman
Published: November 2018

Peripartum cardiomyopathy is one of the potentially life-threatening complications of pregnancy. It is characterized by symptoms of heart failure in the last months of gestation or within five months after birth. The objective of this case report was to report a case of peripartum cardiomyopathy. A 20-years-old (G1P0) pregnant woman was referred for further evaluation of heart failure in pregnancy. The patient’s family and medical histories were both unremarkable. She had a 36 weeks and 2 days dichorionic diamniotic twin pregnancy. Emergency cesarean section was performed under spinal anesthesia. During the early postoperative period, the patient complaint of respiratory distress and the diagnosis of peripartum cardiomyopathy was confirmed with physical examination, laboratory and echocardiography findings. She was transferred to the cardiac intensive care unit and received supplemental oxygen, noninvasive ventilation and intravenous infusion of lidocaine. She well tailored the medical therapy and she and her babies were discharged uneventfully after 10 days of delivery.The clinicians should keep in mind the diagnosis of peripartum cardiomyopathy in young woman with twin pregnancy in third trimester who presents with symptoms of heart failure even after delivery. Emergent cardiologic evaluation and intervention must be done for this rare and potentially morbid and mortal condition.Keywords: Ejection fraction, Peripartum cardiomyopathy, Pregnancy
A case report of simultaneous mini-invasive treatment of a patient with kidney tumor and tumor thrombus in inferior vena cava
Authors: Mosoyan M. , Chernyavskiy M. , Chernov A. , Mamsurov M. , Chuykova I.
Published: November 2018

Nowadays, there is a tendency in surgery to use more minimally invasive surgical procedures to decrease the risk of intra- and postoperative complications and to reach a faster rehabilitation period. We report a case of successful simultaneous minimally invasive treatment of a patient with kidney tumor. According to ultrasound examination data, the patient had a tumor in the right kidney. A computed tomography scan of the abdomen verified the tumor and detected a thrombus in the inferior vena cava lumen. Embolization of the right renal artery was performed as the first stage in the hybrid operating room. Right-side nephrectomy and thrombectomy from inferior vena cava, as the second stage, were done by using a robotic surgical system. The feature of this case is that embolization and nephrectomy were simultaneously performed during one surgical procedure. On the 10th day, the patient was discharged from the hospital without any signs of deterioration and complications. Thus, the unique work of two surgical teams proficient in mini-invasive technologies allowed to eliminate tumors and tumor thrombi in a single procedure and to reduce the bleeding, in-hospital stay, and rehabilitation period. This method will help more patients with kidney tumors in the future.
Received 28 June 2018. Revised 3 August 2018. Accepted 6 August 2018.
Informed consent: The patient’s informed consent to use his records for medical purposes is obtained.
Funding: The study did not have sponsorship.
Conflict of interest: The authors declare no conflict of interest.
Perspectives of Plant Natural Products in Inhibition of Cancer Invasion and Metastasis by Regulating Multiple Signaling Pathways
Authors: Sarwar Md. Shahid , Zhang Hong-Jie , Tsang Siu Wai
Published: November 2018

Background:

Metastasis is often derived from increased invasion and migration of tumor
cells, and is the most frequent cause of cancer-associated death. Either the prophylactic or therapeutic
treatment of metastatic cancer remains very challenging today by virtue of the complex histopathology
and genetic or epigenetic variations. Medicinal scientists had discovered many potential anti-invasive
and anti-metastatic compounds from plant materials. However, data on currently available plant-based
compounds inhibiting cancer invasion and metastasis is relatively scanty and no published article has
been found with updated information in this unique and important aspect.

Methods:

We obtained relevant information from a structured search of 327 peer-reviewed articles,
including both research- and review-based papers, related to the use of plant materials in cancer treatments,
particularly for the suppression of invasion and metastasis.

Results:

We have categorized the plant-based products with anti-invasive or anti-metastatic properties
into alkaloids, flavonoids, terpenes, quinones, phenolics, xanthone and sulfur-containing compounds,
and complemented with their chemical structures, sources of isolation and biological targets in the present
review article.

Conclusion:

We aim to provide readers a convenient way in reviewing the potential anti-invasive and
anti-metastatic plant-based products with links to different mechanistic pathways, and to inspire researchers
with updated information for the development of new anticancer remedies.
Cancer Treatment by Using Traditional Chinese Medicine: Probing Active Compounds in Anti-multidrug Resistance During Drug Therapy
Authors: Lou Jian-Shu , Yao Ping , Tsim Karl W.K.
Published: November 2018

The main challenge of cancer treatment is multidrug resistance during chemotherapy.
Cancer cell can evade cell death during every round of orthodox chemotherapy
drugs, consequently being resistant after several rounds of standard drug treatment. One
of the regimens to address this multidrug resistance problem is by drug combination.
However, synthetic drugs always have problems of strong side effects and toxicity. Natural
compounds deriving from traditional Chinese medicine are known to have low toxicity
and genuine promising effects in reversing multidrug resistance, either induced by orthodox
chemotherapeutic or targeted therapy drugs. Numerous mechanisms including suppression
of drug efflux, detoxifying systems, DNA repair systems, and anti-apoptosis
pathways were responsible for such process. A range of natural compounds functioned on
the suppression of apoptosis are widely reported, which include flavonoids, terpenoids,
alkaloids, quinones, xanthones, saponins and polysaccharides. Here, this review summarized
comprehensive data from in vitro and in vivo studies to elucidate the functional roles
of natural compounds in reversing multidrug resistance during cancer therapy.
Current Trends in Protein Engineering: Updates and Progress
Authors: Sinha Rajeshwari , Shukla Pratyoosh
Published: November 2018

Proteins are one of the most important and resourceful biomolecules that find applications
in health, industry, medicine, research, and biotechnology. Given its tremendous relevance, protein
engineering has emerged as significant biotechnological intervention in this area. Strategic utilization
of protein engineering methods and approaches has enabled better enzymatic properties, better stability,
increased catalytic activity and most importantly, interesting and wide range applicability of proteins.
In fact, the commercialization of engineered proteins have manifested in economically beneficial
and viable solutions for industry and healthcare sector. Protein engineering has also evolved to become
a powerful tool contributing significantly to the developments in both synthetic biology and metabolic
engineering. The present review revisits the current trends in protein engineering approaches such as
rational design, directed evolution, de novo design, computational approaches etc. and encompasses
the recent progresses made in this field over the last few years. The review also throws light on advanced
or futuristic protein engineering aspects, which are being explored for design and development
of novel proteins with improved properties or advanced applications.
Sucrose Acetate Isobutyrate as an In situ Forming Implant for Sustained Release of Local Anesthetics
Authors: Li Hanmei , Xu Yuling , Tong Yuna , Dan Yin , Zhou Tingting , He Jiameng , Liu Shan , Zhu Yuxuan
Published: November 2018

Objective:

In this study, an injectable Sucrose Acetate Isobutyrate (SAIB) drug delivery system (SADS) was designed and fabricated for the sustained release of Ropivacaine (RP) to prolong the duration of local anesthesia.

Methods:

By mixing SAIB, RP, and N-methyl-2-pyrrolidone, the SADS was prepared in a sol state with low viscosity before injection. After subcutaneous injection, the pre-gel solution underwent gelation in situ to form a drug-released depot.

Result:

The in vitro release profiles and in vivo pharmacokinetic analysis indicated that RP-SADS had suitable controlled release properties. Particularly, the RP-SADS significantly reduced the initial burst release after subcutaneous injection in rats.

Conclusion:

In a pharmacodynamic analysis of rats, the duration of nerve blockade was prolonged by over 3-fold for the RP-SADS formulation compared to RP solution. Additionally, RP-SADS showed good biocompatibility in vitro and in vivo. Thus, the SADS-based depot technology is a safe drug delivery strategy for the sustained release of local anesthetics with long-term analgesia effects.
On the Mechanisms of Action of the Low Molecular Weight Fraction of Commercial Human Serum Albumin in Osteoarthritis
Authors: Bar-Or David , Thomas Gregory , Rael Leonard T. , Frederick Elizabeth , Hausburg Melissa , Bar-Or Raphael , Brody Edward
Published: November 2018

:

The low molecular weight fraction of commercial human serum albumin (LMWF5A)
has been shown to successfully relieve pain and inflammation in severe osteoarthritis of the knee
(OAK). LMWF5A contains at least three active components that could account for these antiinflammatory
and analgesic effects.

:

We summarize in vitro experiments in bone marrow–derived mesenchymal stem cells, monocytic
cell lines, chondrocytes, peripheral blood mononuclear cells, fibroblast-like synoviocytes, and endothelial
cells on the biochemistry of anti-inflammatory changes induced by LMWF5A. We then
look at four of the major pathways that cut across cell-type considerations to examine which biochemical
reactions are affected by mTOR, COX-2, CD36, and AhR pathways. All three components
show anti-inflammatory activities in at least some of the cell types.

:

The in vitro experiments show that the effects of LMWF5A in chondrocytes and bone marrow–
derived stem cells in particular, coupled with recent data from previous clinical trials of single and
multiple injections of LMWF5A into OAK patients demonstrated improvements in pain, function,
and Patient Global Assessment (PGA), as well as high responder rates that could be attributed to
the multiple mechanism of action (MOA) pathways are summarized here. In vitro and in vivo data
are highly suggestive of LMWF5A being a disease-modifying drug for OAK.
Synthesis and In Vitro Evaluation of Tetrahydroquinoline Derivatives as Antiproliferative Compounds of Breast Cancer via Targeting the GPER
Authors: Zacarías-Lara Oscar J. , Méndez-Luna David , Martínez-Ruíz Gustavo , García-Sanchéz José R. , Fragoso-Vázquez Manuel J. , Bello Martiniano , Becerra-Martínez Elvia , García-Vázquez Juan B. , Correa-Basurto José
Published: November 2018

Background:

Some reports have demonstrated the role of the G Protein-coupled Estrogen
Receptor (GPER) in growth and proliferation of breast cancer cells.

Objective:

In an effort to develop new therapeutic strategies against breast cancer, we employed an in
silico study to explore the binding modes of tetrahydroquinoline 2 and 4 to be compared with the reported
ligands G1 and G1PABA.

Methods:

This study aimed to design and filter ligands by in silico studies determining their Lipinski's
rule, toxicity and binding properties with GPER to achieve experimental assays as anti-proliferative
compounds of breast cancer cell lines.

Results:

In silico studies suggest as promissory two tetrahydroquinoline 2 and 4 which contain a carboxyl
group instead of the acetyl group (as is needed for G1 synthesis), which add low (2) and high
hindrance (4) chemical moieties to explore the polar, hydrophobic and hindrance effects. Docking and
molecular dynamics simulations of the target compounds were performed with GPER to explore their
binding mode and free energy values. In addition, the target small molecules were synthesized and assayed
in vitro using breast cancer cells (MCF-7 and MDA-MB-231). Experimental assays showed that
compound 2 decreased cell proliferation, showing IC50 values of 50µM and 25µM after 72h of treatment
of MCF-7 and MDA-MB-231 cell lines, respectively. Importantly, compound 2 showed a similar
inhibitory effect on proliferation as G1 compound in MDA-MB-231 cells, suggesting that both ligands
reach the GPER-binding site in a similar way, as was demonstrated through in silico studies.

Conclusion:

A concentration-dependent inhibition of cell proliferation occurred with compound 2 in
the two cell lines regardless of GPER.
Переход между электронной локализацией и антилокализацией, а также проявление фазы Берри в графене на поверхности SiC
Authors: Агринская Н.В. , Лебедев А.А. , Лебедев С.П. , Шахов М.А. , Lahderanta E.
Published: November 2018

AbstractIt is shown that the transport properties of graphitized silicon carbide are controlled by a surface graphene layer heavily doped with electrons. In weak magnetic fields and at low temperatures, a negative magnetoresistance is observed due to weak localization. A crossover in the magnetoresistance from weak localization to weak antilocalization (the latter is the manifestation of the isospin in graphene) is observed for the first time in samples of this kind at elevated temperatures. A pronounced pattern of Shubnikov–de Haas oscillations is observed in strong magnetic fields (up to 30 T). This pattern demonstrated fourfold carrier spectrum degeneracy due to the double spin and double valley degeneracies. Also, the manifestation of the Berry phase is observed. The effective electron mass is estimated to be m * = 0 . 08 m _0, which is characteristic of graphene with a high carrier concentration.
Модуль объемного сжатия крупно- и нанокристаллического сульфида серебра
Authors: Садовников С.И.
Published: November 2018

AbstractThe change in the bulk modulus of coarse-crystalline and nanocrystalline silver sulfides is determined in the temperature range 300–960 K using the experimental data on the temperature dependences of the heat capacity and the thermal expansion coefficients of these materials. The bulk modulus of the nanocrystalline silver sulfide is found to be lower in magnitude than modulus B of the coarse-crystalline silver sulfide in this temperature range.
Расчет модуля Юнга одностенных нанотрубок на основе MoS-=SUB=-2-=/SUB=- с использованием силового поля и гибридного метода теории функционала плотности
Authors: Бандура А.В. , Лукьянов С.И. , Эварестов Р.А. , Куруч Д.Д.
Published: November 2018

AbstractA force field is proposed that reproduces with a high accuracy a large number of properties of the bulk crystal MoS_2 phases, monolayers, and nanotubes. The reproduced values are both the experimental results and the results of quantum chemical calculations. The elaborated interaction potential can be useful primarily for investigation of multiwall MoS_2 nanotubes and their thermodynamic properties, especially, since the potential is able to reproduce the frequencies of the crystal phonon spectrum. In this study the proposed potential is applied to simulate the temperature dependence of a number of properties of the armchair and zigzag nanotubes. The calculations have been performed using molecular mechanics method within the framework of quasi harmonic approximation which is carried out through the estimation of the temperature dependence of the Helmholtz free energy.
Модифицирование структуры многостенных углеродных нанотрубок с использованием непрерывного и импульсного ионных пучков
Authors: Корусенко П.М. , Несов С.Н. , Поворознюк С.Н. , Болотов В.В. , Князев Е.В. , Пушкарев А.И. , Смирнов Д.А.
Published: November 2018

AbstractChanges in the local atomic and electronic structure and the chemical state of the surface of multiwalled carbon nanotubes (MWCNTs) irradiated with continuous and pulsed ion beams are studied using transmission electron microscopy, X-ray photoelectron spectroscopy, and X-ray absorption near-edge spectroscopy. It is demonstrated that changes in the structure and the chemical state of MWCNTs under continuous irradiation with argon ions are attributable to the radiation-induced defect formation. When a pulsed carbon–proton beam is used, thermal effects exert a considerable influence on the structure of carbon nanotubes. The obtained results suggest that continuous and pulsed ion beams are suitable for targeted functionalization of physical and chemical properties of MWCNTs.
Позиционно-чувствительный спектрометрический модуль для регистрации ионизирующего излучения полупроводниковыми стриповыми детекторами
Authors: Тубольцев Ю.В. , Богданов А.А. , Ерёмин И.В. , Ерёмин В.К. , Чичагов Ю.В. , Фомичев А.С. , Аруев Н.Н.
Published: November 2018

AbstractA position-sensitive module for detecting ionizing radiation based on semiconductor strip detectors and a multichannel spectrometric route has been developed and implemented. The dynamic range of the detected charge generated by an ionizing particle in the detector is 5–250 fC. The position-sensitive module is a structurally complete device with the functions of amplifying the spectrometric signal, digitizing, buffering, preprocessing, and transmitting data to a computer.
Оценки вариабельности сердечного ритма методом рекуррентных графиков
Authors: Гиляров В.Л.
Published: November 2018

AbstractThe variability of the heart rate of people depending on their age was analyzed for the first time using numerical characteristics of recurrence plots. The results are comparable with the data obtained by multifractal analysis. It is noted that the method of recurrence plots has a significant advantage since it requires a much smaller number of time counts and, therefore, can be used for rapid diagnostics in extreme situations.
Особенности вольт-амперных характеристик и механизм высокоэффективной генерации электронного пучка в непрерывном открытом разряде
Authors: Бохан П.А. , Гугин П.П. , Закревский Дм.Э.
Published: November 2018

AbstractThe main features of a continuous open discharge used to generate electron beams in medium-pressure gases are discussed. I – V characteristics have been investigated, current and energy efficiencies have been measured, and conditions for obtaining a high (comparable with the anode geometric transparency) energy efficiency of beam generation in helium at a pressure of 10–30 Torr and its mixtures with oxygen have been established. Fundamental differences between the investigated and anomalous discharges have been found. In particular, a Z-shaped I – V characteristic has been obtained and attributed to the modification of the role of main electron emission mechanisms with increasing voltage.
Изготовление и исследование коммутирующих p-n-переходов для каскадных фотопреобразователей
Authors: Левин Р.В. , Маричев А.Е. , Контрош Е.В. , Прасолов Н.Д. , Калиновский В.С. , Пушный Б.В.
Published: November 2018

AbstractSome results of studies on the creation of new junction elements for application in monolithic multijunction InP based photovoltaic cells are presented. A new type of junction elements with a specific ohmic resistance of less than 2 mΩ cm^2 within a range of current densities of up to 700 A/cm^2 is presented as an alternative to tunnel junctions.
Наногетероструктуры AlInGaPAs/GaAs/Si для фотоэлектрических преобразователей, полученные методом импульсного лазерного напыления
Authors: Лунин Л.С. , Лунина М.Л. , Казакова А.Е. , Пащенко А.С. , Алфимова Д.Л. , Арустамян Д.А.
Published: November 2018

AbstractThe pulsed laser deposition method has been used to fabricate AlInGaPAs/GaAs/Si nanoheterostructures for cascaded photoelectric converters operating at wavelengths in the range of 300–1300 nm. The structural and luminescent structures of AlInGaPAs nanofilms on GaAs and GaAs on Si were studied. The spectral characteristics of photocells in an AlInGaPAs/GaAs/Si triple-cascade photoelectric converter were examined.
¿Cómo enseñan psicología los profesores efectivos? Un estudio exploratorio
Authors: Carlos Guzmán José Jesús
Published: November 2018

Diversos estudios muestran que la enseñanza de la psicología se imparte en forma tradicional, por lo que surge la necesidad de buscar nuevos modos de enseñarla. Para ello se entrevistó a profundidad a 15 profesores de la Facultad de Psicología de la UNAM calificados como buenos por sus alumnos. Los entrevistados mostraron gusto por enseñar y por buscar una buena relación interpersonal con los alumnos, además de que fomentan la retroalimentación y muestran gran compromiso y responsabilidad docente. Se analizan las aportaciones de la investigación en el diseño de programas de formación docente y las ventajas de considerar en ella otros elementos aparte de los estrictamente instruccionales.
Trayectorias laborales y movilidad de los biólogos agropecuarios de la Universidad Autónoma de Tlaxcala
Authors: Jiménez Vásquez Mariela Sonia
Published: November 2018

La creación de carreras profesionales híbridas abre horizontes de análisis y nuevas interrogantes de los procesos de desarrollo profesional, así como de las situaciones sociales y laborales que viven los egresados al acceder al mercado de trabajo. El análisis de la movilidad interna y externa a partir de un estudio de trayectorias laborales permitió conocer dos aspectos básicos que enfrentan los egresados de la licenciatura en Biología agropecuaria: las características y condiciones del mercado de trabajo en un contexto de flexibilización y precarización de las condiciones laborales y los efectos de factores de influencia como el capital relacional, el periodo de egreso, los estudios de posgrado y el género en la adscripción de los egresados hacia trayectorias de mayor o menor estabilidad y logros laborales.
Percepciones y supuestos sobre la enseñanza de la ciencia. Las concepciones de los investigadores universitarios
Authors: Alvarado Rodríguez María Eugenia , Flores Camacho Fernando
Published: November 2018

Se presentan resultados de un estudio con investigadores de diversas áreas científicas de la UNAM en relación a sus concepciones sobre la enseñanza de la ciencia en el marco universitario. El texto forma parte de un estudio sobre el origen y desarrollo de las concepciones de ciencia que prevalecen entre los investigadores en ciencias. Se aborda un breve panorama en relación a la investigación educativa en la enseñanza de las ciencias para, posteriormente, presentar las ideas expresadas por diversos investigadores en torno a la enseñanza de la ciencia y del aprendizaje, como son: ideas y perspectivas en formación y actualización docente, desvinculación docencia investigación, infraestructura y problemas de índole económica, y obstáculos para la enseñanza de la ciencia. En el desarrollo del trabajo se muestra el tipo de ideas que tienen los investigadores en torno a la enseñanza de la ciencia y se hace un análisis crítico y comparativo de tales ideas y concepciones. Se muestran los problemas que subyacen a concepciones ingenuas sobre los procesos de enseñanza y aprendizaje y se anotan algunas implicaciones en torno a las dificultades de mejorar la educación científica en la universidad.
Sobre los complejos procesos de exclusión e integración en España
Authors: Beas Miranda Miguel
Published: November 2018

Pese a los avances evidentes que en todos los ámbitos se han producido en España, aún persisten bolsas de pobreza y de exclusión cuya erradicación no puede basarse en soluciones parciales, sino que éstas tienen que ser integrales; la educación cumple un papel relevante en relación a este fenómeno. Hablar de la exclusión es hacerlo sobre un problema fundamental que está en las agendas políticas, sociales y culturales; es por ello que en este artículo se precisará su concepto, se desvelan algunas de sus causas y se analizan sus ámbitos y sus características. Existen ciertas circunstancias, lamentablemente muy arraigadas a una densa tradición histórica, que agravan el problema de la exclusión, como son el género, la edad y los movimientos migratorios; aquí se analiza solamente el riesgo de exclusión que tiene la inmigración en España. Consideramos que las propuestas de integración pasan por el reconocimiento de los otros, de su diversidad, de la igualdad como un derecho inalienable y la participación de las personas directamente implicadas en todos los ámbitos socioculturales.