Artificial Port Research Articles

Liver Function Following Carbon-Di-Oxide Pneumoperitoneum in Laparoscopic Cholecystectomy

Background: Laparoscopic surgery is performed by the insufflation of gas like carbon di oxide (CO2) into the peritoneal cavity by artificial port which is called creating pneumoperitoneum. The CO2 pneumoperitoneum causes changes in the splanchnic microcirculation and can affect liver physiology. Although laparoscopic cholecystectomy offered many advantages over laparotomy, new concerns arose regarding the effects of CO2 pneumoperitoneum on liver function. Knowledge of the effects of CO2 pneumoperitoneum on liver function can help minimize complications while profiting from the benefits of LC without concerns about its safety. It was noticed in many studies that following laparoscopic cholecystectomy (LC), liver function parameters were disturbed. Aims: To observe any alteration in liver function by carbon dioxide pneumoperitoneum in laparoscopic cholecystectomy. Methods: Ninety-four patients with cholelithiasis having normal liver function enrolled in this study. Test obtained preoperatively including serum bilirubin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) then 24 &72 hour post operatively to compare and proceed. Statistical analyses of the results were obtained by using window-based computer software devised with Statistical Packages for Social Sciences (SPSS22). Results: The findings showed that mean duration of pneumoperitoneum was 43.8±9.1minutes. The mean serum bilirubin pre-operatively was 0.75±0.21 (mg/dL), post-operative 24 hours value was 0.77±0.23 (mg/dL) and post-operative 72 hours value was 0.73±0.18 (mg/dL). No significant difference was observed in pre-operative and postoperative values. The mean serum ALT preoperatively was 33.81±7.83 (IU/L), post-operative 24 hours value was 52.51±25.9 (IU/L) and postoperative 72 hours value was 46.3±21.33 (IU/L). The mean serum AST pre-operatively was 33.84±6.83 (IU/L), post-operative 24 hours value was 48.94±19.23 (IU/L) and post-operative 72 hours value was 44.36±15.7 (IU/L). The mean serum alkaline phosphatase pre-operatively was 72.57±25.95 (IU/L), post-operative 24 hours value was 88.26±41.69 (IU/L) and post-operative 72 hours value was 85.32±38.85 (IU/L). There were significant increase of post-operative 24 hours and 72 hours value of liver enzymes when compared to preoperatively. Conclusion: There was significant increase in, AST, ALT, ALP post-operative 24 hours and 72 hours after doing laparoscopic cholecystectomy when compared to preoperatively. There may be a transient elevation of hepatic enzymes after LC and the major causative factor seemed to be CO2 pneumoperitoneum.

Non-linear periodic long waves based on Boussinesq equation for shallow water waves: A coupled FEM modeling

A coupled mathematical model is developed based on the non-linear Boussinesq equation (BE) for shallow water waves to investigate the influence of the periodic non – linear long waves inside the irregular domain. A coupled numerical model based on the solution of the BE in a bounded region with the incorporation of the effects of viscous dissipation, dispersion, convective non-linearities, and variable bathymetry is obtained by using Galerkin Finite Element Method (GFEM), and an analytical approach based on Fourier-Bessel series solution for the scattered waves in unbounded region. The current coupled numerical model is validated by comparing the simulation results with existing studies. Moreover, the accuracy of the current scheme is also examined using convergence analysis for the rectangular domain. The present numerical model is applied on T and TT–shaped harbors to investigate the role of geometry to induce the amplification. In addition, the current approach implemented on the realistic Paradip port, Odisha, India, and Pohang New Harbor (PNH), South Korea at six record stations for practical implication. Therefore, the present numerical model can be utilized to construct/redesign an artificial port in the coastal region including variable bathymetry considering the effect of partial reflection, dissipation, and convective non – linearities.

Experimental Instructional Design of Code Slicing and Data Verification by Artificial Interruption

Students run code directly without any modification when doing programming experiments. They do not care about the process and do not understand the results. It has always been the pain of the electronic information experiment teaching mentioned by. This article, combines the previous teaching experience, proposes an artificial serial port interruption in the code. The result data returned by the interrupt upload to computer or mobile phone, combined with the experimental principle to allow students to explore the relationship between input and output, so that students can fully participate in the modification of code parameters, and verify the intermediate results. Students connect to the WIFI hotspot configured in the experiment box through their mobile phones, and lunch the online commissioning APP serial port configuration interface to complete the basic serial port settings. The slave MCU needs to download the firmware code compiled in C language in advance. The code contains the serial port output function to calibrate the running position of the code and upload the specified operation results. This article briefly describes the hardware functional chart and the functional flowchart of the interrupt code; focusing on the interface design and interrupt implementation method of online commissioning APP, as well as the test environment setup and specific test results with serial port tools.

Modeling of shallow water waves with variable bathymetry in an irregular domain by using hybrid finite element method

An efficient numerical model is constructed with the combination of analytical and Hybrid Finite Element Method (HFEM) based on mild slope equation for shallow water waves to analyze the wave induced oscillation in an irregular geometrical domain. The domain of interest is divided in two regions as bounded and unbounded region. The solution of the mild slope equation is obtained in the bounded region with the consideration of variable bathymetry and partially reflected boundary using Hybrid element method. Further, an analytical approach is utilized in an unbounded region based on Fourier bessel series solution of scattered waves. Hybrid mesh elements is considered for bounded region to enhance the numerical accuracy. The numerical validation is conducted by the comparison of simulation results with analytical approximations and convergence analysis for the rectangular domain is also obtained. The amplification factor is obtained for T-shaped and TT-shaped domain to analyze the resonance modes. Finally, the current numerical model is applied on a realistic Pohang New Harbor (PNH) under the resonance conditions. Thus, the current numerical model can be utilized efficiently for redesigning and constructing artificial ports or harbors in the coastal regions with variable bathymetries.

Analysis of sedimentation at the fishing harbor entrance: case study of El-Burullus, Egypt

Sedimentation in artificial ports and harbors is a common issue throughout the world. Based on an assessment of the coastal fishing harbors in Egypt, the El-Burullus fishing harbor has been found to suffer severely from siltation. Sediment deposits are concentrated at the harbor entrance, which threatens navigation through this area. Although the harbor authority has constructed a perpendicular extension on the main breakwater to mitigate these siltation issues, fishing boats are still suffering from the siltation at the harbor entrance. Dredging is required every year to maintain continuity of navigation through the harbor; the cost of dredging is a critical element which impacts the economic feasibility of the harbor. Therefore, the need to investigate new solutions for the siltation issue is critical. In this study, a two-dimensional calibrated and validated model using the Coastal Modeling System package is used to understand the coastal processes within the study area. It is also used to investigate the effects of the proposed breakwater extension on the siltation at the harbor outlet. Field data such as hydrographic surveys, waves, tides, and lake outlet discharge data were collected and included in the model. The results obtained for the current breakwater conditions confirmed the claims of the fishermen that the sedimentation problem still occurs at the entrance. Thus, five possible solutions to mitigate the problem were proposed and simulated considering the following parameters: sediment deposition rate to the west of the main breakwater, the erosion rate in front of the seawall in the eastern part of the harbor, and the morphological changes within the El-Burullus lake outlet. According to the simulation results, reducing the length of the upper edge of the middle jetty by 90 m improves the stability of the harbor entrance. Alternatively, replacing the perpendicular extension by an inclined extension of 60 m in length and shortening the middle jetty by 60 m reduces the accretion and erosion rates around the harbor which promotes the long-term stability for the coastal area in addition to favorable conditions to the El-Burullus harbor entrance.

Approach to the Construction of Green Port in Tianjin Port

Transportation is one of the main sources of carbon emission, and it is also an important area for reducing greenhouse gas emission and alleviating climate change. Tianjin port is the largest artificial port in China, and it is also an important port in China. The construction of green port can effectively control the energy consumption and pollutant discharge of the port. From five aspects of improving management ways, strengthening propaganda and training, clean energy utilization, technological transformation and environmental protection, this paper puts forward relevant measures for Tianjin port to build green ports, so as to effectively guide Tianjin port to carry out the construction of green ports.

Rome’s urban history inferred from Pb-contaminated waters trapped in its ancient harbor basins

Heavy metals from urban runoff preserved in sedimentary deposits record long-term economic and industrial development via the expansion and contraction of a city's infrastructure. Lead concentrations and isotopic compositions measured in the sediments of the harbor of Ostia-Rome's first harbor-show that lead pipes used in the water supply networks of Rome and Ostia were the only source of radiogenic Pb, which, in geologically young central Italy, is the hallmark of urban pollution. High-resolution geochemical, isotopic, and 14C analyses of a sedimentary core from Ostia harbor have allowed us to date the commissioning of Rome's lead pipe water distribution system to around the second century BC, considerably later than Rome's first aqueduct built in the late fourth century BC. Even more significantly, the isotopic record of Pb pollution proves to be an unparalleled proxy for tracking the urban development of ancient Rome over more than a millennium, providing a semiquantitative record of the water system's initial expansion, its later neglect, probably during the civil wars of the first century BC, and its peaking in extent during the relative stability of the early high Imperial period. This core record fills the gap in the system's history before the appearance of more detailed literary and inscriptional evidence from the late first century BC onward. It also preserves evidence of the changes in the dynamics of the Tiber River that accompanied the construction of Rome's artificial port, Portus, during the first and second centuries AD.

Principle and basic property of the sequential flow pump.

In the emergency care field, early treatment of acute heart or respiratory failure has been a global concern. In severe cases, patients are frequently required to be on an extracorporeal membrane oxygenator (ECMO) life support. To make the ECMO system more compact and portable, we proposed a sequential flow-type centrifugal pump named the sequential flow pump (SFP). In this study, principle and basic properties of this novel blood pump were examined by computational fluid dynamic (CFD) analysis and an experimental model. In the SFP, fluid is given centrifugal force sequentially twice with a single closed impeller. This sequential pressurization mechanism enables high-pressure output without high impeller speed. To realize easy integration of a blood pump with an artificial lung, the inlet and outlet ports are located at lateral side and center of the pump, respectively, which is the reverse configuration of conventional centrifugal pumps. The computational model was composed for CFD analysis and the experimental model was developed for the experiment of the actual pump. For both models, dimension of the impeller and volute was designed to be equal. In the CFD analysis, the SFP could generate higher performance than the single pressurization model with the same rotational speed of the impeller. Basic property of the experimental model was very similar to that of the computational model. The results showed the possibility that the SFP would be more suitable for the compact ECMO system than conventional centrifugal pumps.

The Jetty with Platform: A Distinctive Port Structure from North Africa

A distinctive type of artificial port structure has been found in Africa proconsularis, but not elsewhere in the Mediterranean. This structure is identified here as a ‘jetty with platform’, due to its main components: a straight jetty extending from the shoreline and a large platform attached to the outer end of the jetty. The article considers the chronological, environmental, and technological factors that may be responsible for the construction of this type of jetty, which is found at Acholla, Gigthis, Leptiminus, Ras Segala, and possibly Lepcis Magna.

Africa in the Roman Empire: Connectivity, the Economy, and Artificial Port Structures

The relationship between connectivity and economic activity is a subject of current debate in Mediterranean archaeology, and recent scholarship has shown the significance of this topic for North African studies. This article approaches the issue through a body of evidence that has hitherto been overlooked: artificial port structures, such as jetties, quays, enclosures, and breakwaters. I identify 29 definite, and 16 possible, structures between Cyrenaica and Mauretania Tingitana dating between the fourth century B.C.E. and the sixth century C.E. I demonstrate that the archaeological evidence for these structures is a more reliable source of information than the ancient literary evidence and discuss how the picture drawn from the latter has misled earlier scholars. I argue that wharf length is the best measure of the size of port structures, and I use that concept to outline the role that individual ports and broader regions played in Mediterranean commerce. By relating artificial port structures to the major production centers of exported goods, I enhance the picture of the North African economy both before and during the Roman empire.*

Little tern breeding success in artificial and natural habitats: modelling population growth under uncertain vital rates

AbstractAs a consequence of habitat loss, breeding in man‐made habitats has become increasingly common for many coastal breeding bird species. While artificial sites provide valuable substitutes, they may also be more attractive, and importantly, differ in quality from natural sites. Therefore, information on habitat specific breeding success and their potential for supporting stable populations are needed. We compared little tern (Sternula albifrons) breeding success (nest and hatching success) between natural habitat (sandy beaches) and artificial port habitat at Bothnian Bay, Finland from 2006 to 2011. We further reviewed published estimates on pre‐fledging and adult survival for little terns and least terns (Sternula antillarum), and used these ranges to estimate plausible parameter spaces for population growth rates given our estimates of breeding success. Nest success was among the highest reported for little terns in the artificial habitat (82 %) while being lower in the natural habitat (58 %). This difference may have resulted from differences in colony sizes and levels of disturbance. Hatching success did not differ significantly, but the percentage of successful nests containing unhatched eggs was twice as high in the natural habitat. The parameter spaces for population growth rates indicated that the artificial habitat has good potential to sustain stable populations (66 % positive growth rate) while for the natural habitat this potential was lower (37 % positive growth rate). While our results suggest that artificial habitats can be very productive breeding sites for habitat deprived tern populations, management should concentrate on improving both habitats with emphasis on natural sites.

Frequency Notched UWB Planar Monopole Antenna Optimization Using a Finite Element Method-Based Approach

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> The objective of this work is the design and optimization of an ultrawideband (UWB) planar monopole antenna with frequency-notched behavior intended to get rid of the 5–6 GHz frequency band for WLAN compatibility purposes. An optimized profile UWB planar monopole designed by means of a Simulated Annealing algorithm and full three-dimensional finite element method, detailed in a companion paper, was considered as the design starting point. In order to design the band-notched rejection no full finite element analysis is carried out on each profile modification as is usual. The procedure is based on a genetic algorithm and a multipurpose admittance matrix approach instead. Artificial ports are allowed in the computational domain and an admittance-type matrix comes up. As a result, a multiport network describes the electromagnetics within the analysis domain. Circuit manipulations of this network efficiently outperform full-wave analyses for different monopole modifications, thus making it possible to use this strategy in a computer aided-design scheme. </para>

A new iterative diakoptics-based multilevel moments method for planar circuits

This paper combines a multilevel moments method (MMM) scheme with a modified diakoptics (MD) technique and a block Gauss-Seidel (BGS) iterative technique to reduce the solution time of large planar microwave structures. The proposed MMM scheme has two levels. On the lower level, the planar circuit is divided into several subcircuits using two types of artificial ports. At the higher level, general basis functions defined over the complete circuit are generated in an iterative way. The validity and the efficiency of the new technique are validated by several examples, including a large low-pass filter.