Specialized ESP Layouts for the Operation of Deep Wells Confined to the Category of Hard-to-Recover Reserves

The article is devoted to the selection of a specialized configuration of submersible equipment to minimize downhole pressure in order to intensify the flow of fluid to the wells of Gazpromneft-Orenburg. The depth of the wells and the design features of the well do not allow sufficient depth of the pumping equipment (top of the perforation interval 3800-4200 m). In addition, the operation of the fund is complicated by abnormally low reservoir pressures (60-120 at), low filtration-capacity properties and high linear pressures of single-standing wells (20-30 at). To increase the productivity of wells, the ESP layout was used with a two-way engine, two submersible pumps and a shank. The layout is chosen in such a way as to reduce the density of the liquid column under the pump due to the circulation of the liquid by the lower pump. A special feature of the design was the selection of the length and the limit of the descent of the shank, the ratio of performance and pressure of the upper and lower pumps and a number of pre-connected devices as part of the layout. Pilot tests were conducted at three wells of the Gazpromneft-Orenburg field. After the installation and commissioning work in the process of bringing the wells to the established mode, the features of the ESP that differ from the standard operation, leading to an increase in the period of stable well production, were revealed. According to the results of the tests, an increase in the oil flow rate of an average of 16 tons per day was obtained. The study of the characteristics of a complete installation directly on the test wells allowed us to determine the technical capabilities of the equipment, the volume-flow characteristics of the fluid under the pump and PVT. The aspects of natural separation and free gas content at the inlet of both pumps are studied, which is also a boundary condition for well intensification. The tests allowed us to assess the technological limit of the layout with two ESP in the conditions of the Gazpromneft-Orenburg field. In contrast to other options for the operation of hard-to-recover wells, the proposed layout has a number of advantages, such as a minimum increase in the cost of construction, simplicity of construction, which ensures high operating time of equipment and low specific energy consumption. Based on the results of testing the pilot installations, a decision was made to replicate this approach in the Company.

Large-scale genomic analysis of antimicrobial resistance in the zoonotic pathogen Streptococcus suis

Background Antimicrobial resistance (AMR) is among the gravest threats to human health and food security worldwide. The use of antimicrobials in livestock production can lead to emergence of AMR, which can have direct effects on humans through spread of zoonotic disease. Pigs pose a particular risk as they are a source of zoonotic diseases and receive more antimicrobials than most other livestock. Here we use a large-scale genomic approach to characterise AMR in Streptococcus suis, a commensal found in most pigs, but which can also cause serious disease in both pigs and humans. Results We obtained replicated measures of Minimum Inhibitory Concentration (MIC) for 16 antibiotics, across a panel of 678 isolates, from the major pig-producing regions of the world. For several drugs, there was no natural separation into ‘resistant’ and ‘susceptible’, highlighting the need to treat MIC as a quantitative trait. We found differences in MICs between countries, consistent with their patterns of antimicrobial usage. AMR levels were high even for drugs not used to treat S. suis, with many multidrug-resistant isolates. Similar levels of resistance were found in pigs and humans from regions associated with zoonotic transmission. We next used whole genome sequences for each isolate to identify 43 candidate resistance determinants, 22 of which were novel in S. suis. The presence of these determinants explained most of the variation in MIC. But there were also interesting complications, including epistatic interactions, where known resistance alleles had no effect in some genetic backgrounds. Beta-lactam resistance involved many core genome variants of small effect, appearing in a characteristic order. Conclusions We present a large dataset allowing the analysis of the multiple contributing factors to AMR in S. suis. The high levels of AMR in S. suis that we observe are reflected by antibiotic usage patterns but our results confirm the potential for genomic data to aid in the fight against AMR.

Physicochemical characteristics and mineral status of honey from different agro-climatic zones of Himachal Pradesh, India

PurposeThe purpose of this study is to assess the quality of honey from different agro-climatic zones of Himachal Pradesh in terms of physicochemical characteristics and mineral status.Design/methodology/approachThree honey-producing locations were selected within each agro-climatic zone, honey sampled from four separate apiaries within each location and analyzed for physicochemical characteristics and mineral status using standard methodologies. The data were analyzed using one-way analysis of variance with one-way classification, after appropriate transformation through online OP-STAT software and MS Excel. The correlation coefficient (r) was also calculated. Principal component analysis was done using XL-STAT software.FindingsThe honey of Zone 4 had highest fructose (36.62%), F:G ratio (1.55), acidity (46.07 meq/kg), vitamin C (25.04 mg/100 g) and diastase (19.22 DN), whereas the pollen density (76,666.67 pollen grains per 10 g), pH (5.94), sucrose (6.94%), hydroxy methyl furfuraldehyde (70.20 mg/kg), amino acid (103.83 mg/100 g), phenols (77.39 mg/100 g), Ca (81.04 mg/kg) and K (354.17 mg/kg) were highest for Zone 2. Highest electrical conductivity (0.24 mS/cm), moisture (16.50 %), glucose (34.20%) and P content (62.93 mg/kg) were recorded for Zone 1. Correlation studies indicated a significant positive correlation between pH and EC; EC and moisture; colour and pollen density. Examining the graphical distribution of the honey samples, a natural separation between honeys of four different agro-climatic zones was obtained.Originality/valueThe impact of geographical/agro-climatic variations in physicochemical characteristics of honey has not been worked out under the present scenario in Himachal Pradesh.

Endoscopic extraperitoneal access to the prostate in the presence of cystostomy fistula: methodology and first results

Introduction. The advantages of extraperitoneal laparoscopic access to the prostate are well known - this is an opportunity to avoid the negative effects of pneumoperitoneum and the natural separation of the abdominal cavity from the surgical field. One of the drawbacks is the need to create an artifical cavity. Presence of a cystostomy fistula can significantly complicate the formation of the preperitoneal cavity. The aim of this research is to analyze our experience in creating extraperitoneoscopic access to the prostate gland in patients with cystostomy fistula. Materials and methods. From 2015 to 2019, we operated on 153 patients using extraperitoneal access to the prostate gland. Of these, 13 had a cystostomy fistula at the time of the surgery. The formation of the space was carried out according to the original technique without spacemaker balloon. After isolation of the fistulous passage, the latter intersected with suturing on the bladder side with 8-shaped (2–0 vicril). Results. In all cases, we were able to form a working space sufficient for surgical intervention. In 10 (76,93%) cases, access was created without opening the abdominal cavity, in 3 cases (23,07%) the abdominal cavity was unintentionally opened. There were no complications associated with the creation of a pre-abdominal space. Discussion. Extraperitoneal access to the prostate reduces the likelihood of damage to the abdominal organs, reduces the angle of inclination of the patient in the Trendelenburg position, does not require the creation of a pneumoperitoneum, with its adverse effect on the cardiovascular system, and also preserves the natural barriers between the surgical area and the abdominal cavity. The presence of a cystostomy in a patient is not an obstacle to this surgical access, the technical feasibility and safety of which was demonstrated in our study. Conclusion. Thus, extraperitoneal access to the prostate gland in the presence of a cystostomy fistula can be safely created in most cases.

Electrostatics and domains in ferroelectric superlattices

The electrostatics arising in ferroelectric/dielectric two-dimensional heterostructures and superlattices is revisited within a Kittel model in order to define and complete a clear paradigmatic reference for domain formation. The screening of the depolarizing field in isolated ferroelectric or polar thin films via the formation of 180° domains is well understood, where the width of the domains w grows as the square-root of the film thickness d , following Kittel’s Law for thick enough films ( w ≪ d ). For thinner films, a minimum is reached for w before diverging to a monodomain. Although this behaviour is known to be qualitatively unaltered when the dielectric environment of the film is modified, we consider the quantitative changes in that behaviour induced on the ferroelectric film by different dielectric settings: as deposited on a dielectric substrate, sandwiched between dielectrics, and in a superlattice of alternating ferroelectric/dielectric films. The model assumes infinitely thin domain walls, and therefore is not expected to be reliable for film thickness in the nanometre scale. The polarization field P(r) does vary in space, deviating from ± P S , following the depolarizing field in linear response, but the model does not include a polarization-gradient term as would appear in a Ginzburg–Landau free energy. The model is, however, worth characterizing, both as paradigmatic reference, and as applicable to not-so-thin films. The correct renormalization of parameters is obtained for the thick-film square-root behaviour in the mentioned settings, and the sub-Kittel regime is fully characterized. New results are presented alongside well-known ones for a comprehensive description. Among the former, a natural separation between strong and weak ferroelectric coupling in superlattices is found, which depends exclusively on the dielectric anisotropy of the ferroelectric layer.

Arquitecturas para el juego en Central Park: aventuras contra la apatía

Children's play architectures propose new uses for urban public space. The intervention of the New York architect Richard Dattner with his "Adventure playground" (1967) in Central Park creates a children's play environment from formal anarchy in which children can imagine their own ways of playing. The proposal of elemental architectures that encourage children to be adventurous was opposed to the apathy inherited from the conservative institutionalized design. Structures linked by a slightly winding concrete wall define living and playing spaces by creating a natural separation of the children's and the adult's environment. The concatenation of iconic forms of children’s plays aims to choreograph the child's personal learning experiences. Dattner's project is the architectural expression of a bold play program. It represents the rebellious attitude of young architects of advanced ideology. It symbolizes the radical change in thinking about the design of the public playground. It considers the need to involve the community in the project phase and is a contribution to the artistic avant-garde movements that vindicated the specific object of minimal expression.

Vector-acoustic full-waveform inversion: Taking advantage of wavefield separation and dealiasing

Vector-acoustic full-waveform inversion (VAFWI) directly inverts vector-acoustic (VA) data, which consist of pressure and particle displacement components, at the cost of conventional acoustic full-waveform inversion (FWI). VA data contain information about the direction of arrival of the recorded seismic waves. In VAFWI, this directional information is taken into account by introducing an appropriate data weighting. With this weighting, in the geometry of a marine seismic experiment, the VAFWI adjoint calculation approximates inverse wavefield extrapolation, resulting in the natural separation of up- and downgoing recorded waves. If the free-surface effects are modeled during the inversion, the wave separation leads to (1) suppression of surface-related artifacts, (2) constructive interference of receiver ghosts with their primaries leading to preservation of the low-frequency content in the adjoint fields, and (3) compensation for insufficient spatial wavefield sampling on the receiver side. The horizontal displacement component helps interpolate the missing data. Synthetic examples demonstrate that for undersampled data, VAFWI consistently recovers the subsurface properties with higher resolution and fewer artifacts than conventional FWI.

Posterior transcallosal intervenous-interforniceal approach to a periaqueductal tumor

Described by Dandy in 1921, the posterior interhemispheric transcallosal approach provides an operative corridor to the pineal region, posterior third ventricle, and upper midbrain. Intervenous-interforniceal and paravenous-interforniceal variants have been utilized for midline and paramidline pathology, respectively. The intervenous-interforniceal variant capitalizes on the natural separation of the internal cerebral veins, which are found medial to the forniceal crura at this level, to provide a safe corridor to the tumor while minimizing the risk of injury to the fornices. Here, the authors describe a posterior interhemispheric transcallosal approach using the intervenous-interforniceal variant for resection of a periaqueductal pilocytic astrocytoma.The video can be found here: https://youtu.be/mtQKEXEveTg.