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Concrete structures are susceptible to cracking, which can compromise their integrity and durability. Repairing them with ordinary Portland cement (OPC) paste causes shrinkage cracks to appear in the repaired surface. Alkali-activated binders offer a promising solution for repairing such cracks. This study aims to develop an alkali-activated paste (AAP) and investigate its effectiveness in repairing concrete cracks. AAPs, featuring varying percentages (0.5%, 0.75%, 1%, 1.25%, 1.5%, and 1.75%) of polyethylene (PE) fibers, are found to exhibit characteristics such as strain hardening, multiple plane cracking in tension and flexure tests, and stress-strain softening in compression tests. AAP without PE fibers experienced catastrophic failure in tension and flexure, preventing the determination of its stress-strain relationship. Notably, AAPs with 1.25% PE fibers demonstrated the highest tensile and flexural strength, exceeding that of 0.5% PE fiber reinforced AAP by 100% in tension and 70% in flexure. While 1% PE fibers resulted in the highest compressive strength, surpassing AAP without fibers by 17%. To evaluate the repair performance of AAP, OPC cubes were cast with pre-formed cracks. These cracks were induced by placing steel plates during casting and were designed to be full and half-length with widths of 1.5 mm and 3 mm. AAP both with and without PE fibers led to a substantial improvement in compressive strength, reducing the initial strength loss of 30%-50% before repair to a diminished range of 2%-20% post-repair. The impact of PE fiber content on the compressive strength of repaired OPC cube is marginal, providing more flexibility in using AAP with any fiber percentage while still achieving effective concrete crack repair. Considering economic and environmental factors, along with observed mechanical enhancements, AAPs show promising potential for widespread use in concrete repair and related applications, contributing valuable insights to the field of sustainable construction materials.
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Álcalis , Materiales de Construcción , Ensayo de Materiales , Polietileno , Polietileno/química , Álcalis/química , Fuerza Compresiva , Resistencia a la Tracción , Estrés MecánicoRESUMEN
Serine proteases are important enzymes widely used in commercial products and industry. Recently, we identified a new serine protease from the desert bacterium Bacillus subtilis ZMS-2 that showed enhanced activity in the presence of Zn2+, Ag+, or H2O2. However, the molecular basis underlying this interesting property is unknown. Here, we report comparative studies between the ZMS-2 protease and its homolog, subtilisin E (SubE), from B. subtilis ATCC 6051. In the absence of Zn2+, Ag+, or H2O2, both enzymes showed the same level of proteolytic activity, but in the presence of Zn2+, Ag+, or H2O2, ZMS-2 displayed increased activity by 22%, 8%, and 14%, whereas SubE showed decreased activity by 16%, 12%, and 9%, respectively. In silico studies showed that both proteins have almost identical amino acid sequences and folding structures, except for two amino acids located in the protruding loops of the proteins. ZMS-2 contains Ser236 and Ser268, whereas SubE contains Thr236 and Thr268. Replacing Ser236 or Ser268 in ZMS-2 with threonine resulted in variants whose activities were not enhanced by Zn2+ or Ag+. However, this single mutation did not affect the enhancement by H2O2. This finding may be used as a basis for engineering better proteases for industrial uses.
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Bacillus subtilis , Proteínas Bacterianas , Peróxido de Hidrógeno , Zinc , Peróxido de Hidrógeno/química , Bacillus subtilis/enzimología , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Zinc/química , Zinc/metabolismo , Serina Proteasas/metabolismo , Serina Proteasas/química , Serina Proteasas/genética , Plata/química , Secuencia de AminoácidosRESUMEN
Microbial alkaline proteases are dominating the global enzyme market with a share of over 65% due to their multifarious catalytic potentials. Hence, production of proteases with novel properties of commercial significance is highly desirable to meet the global enzyme demand. Here, we report the purification, characterization, and pilot-scale application of a serine protease from the desert soil bacterium Bacillus subtilis ZMS-2 with novel properties as dehairing agent in leather processing. The enzyme was purified 16.5-fold with a specific activity of 1543.5 U mg-1 and recovery percentage of 33.6% using ammonium sulfate precipitation, ion exchange, and gel filtration chromatography. The purified enzyme was characterized as a metal ion-, surfactant-, and denaturant-compatible alkaline serine protease having a molecular weight of 36.1 kDa with an optimum activity at pH 8.5 and 60 °C. The catalytic activity of the enzyme was enhanced by Zn+2 (204%), Ag+ (110%), H2O2 (123%), Triton X-100 (110%), iso-octane (109%), chloroform (110%), ethanol (105%), ethyl acetate (110%), and acetonitrile (128%). During pilot-scale applications, the optimum condition was found to be a combination of enzyme (1.5%, 460 U mL-1), sodium sulfide (2%), and calcium hydroxide (lime) (3%). Under this condition, the time required for complete dehairing was 90 min. Chemoenzymatically processed skins exhibited better physical properties than chemically processed skin, including tensile strength (16.35 ± 6.68 N/mm), ball burst (452.88 ± 6.06 N/mm), percent elongation (38.85 ± 1.06 N), tear strength (50.16 ± 4.42 N/mm), and softness (6.5 mm). Electron microscopy analysis of the treated skin showed complete removal of hairs with roots, confirming the keratin specificity of the enzyme. Moreover, the enzyme-assisted dehairing process reduced chemical oxygen demand (COD), biochemical oxygen demand (BOD), total dissolved solids (TDS), and total suspended solids (TSS) by 68, 77, 34, and 39%, respectively. Thus, the alkaline serine protease from B. subtilis ZMS-2 is a potential dehairing agent for the eco-friendly processing of animal skins on industrial scales.
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Left bundle branch area pacing (LBBAP) is an emerging technique in cardiac resynchronization therapy that shows promise in improving ventricular synchrony and clinical outcomes in patients with heart failure. However, the potential risk of coronary artery complications with LBBAP necessitates careful attention and management. This literature review explores the mechanisms, acute coronary events, and clinical implications associated with coronary artery complications in LBBAP. The mechanism of coronary injury with LBBAP involves mechanical trauma, altered coronary blood flow dynamics, and endothelial damage. Acute coronary events such as myocardial ischemia, acute coronary syndromes, and coronary artery dissection can occur during or after LBBAP, leading to significant clinical implications including the need for prompt intervention and potential impact on long-term outcomes. To avoid coronary injury and acute coronary syndrome with LBBAP, specific care strategies are recommended. These include thorough pre-procedural evaluation, expert operator technique, optimization of hemodynamics and ventricular synchrony, close monitoring for ischemic events, collaboration with cardiology specialists, and long-term follow-up. The clinical implications of coronary artery complications with LBBAP necessitate careful patient selection, informed decision-making, and a multidisciplinary approach. Future directions in this field include advancements in procedural techniques, technological innovations, risk stratification strategies, enhanced imaging modalities, research on mechanisms and prevention, and collaboration among stakeholders. By implementing these strategies and focusing on future advancements, healthcare providers can minimize the risk of coronary artery complications with LBBAP and optimize patient outcomes in cardiac resynchronization therapy.
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The enhancement of Robustness (R) has gained significant importance in Scale-Free Networks (SFNs) over the past few years. SFNs are resilient to Random Attacks (RAs). However, these networks are prone to Malicious Attacks (MAs). This study aims to construct a robust network against MAs. An Intelligent Rewiring (INTR) mechanism is proposed to optimize the network R against MAs. In this mechanism, edge rewiring is performed between the high and low degree nodes to make a robust network. The Closeness Centrality (CC) measure is utilized to determine the central nodes in the network. Based on the measure, MAs are performed on nodes to damage the network. Therefore, the connections of the neighboring nodes in the network are greatly affected by removing the central nodes. To analyze the network connectivity against the removal of nodes, the performance of CC is found to be more efficient in terms of computational time as compared to Betweenness Centrality (BC) and Eigenvector Centrality (EC). In addition, the Recalculated High Degree based Link Attacks (RHDLA) and the High Degree based Link Attacks (HDLA) are performed to affect the network connectivity. Using the local information of SFN, these attacks damage the vital portion of the network. The INTR outperforms Simulated Annealing (SA) and ROSE in terms of R by 17.8% and 10.7%, respectively. During the rewiring mechanism, the distribution of nodes' degrees remains constant.
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Current study was undertaken to carry out the genome-wide analysis of a multipotent isolate from desert soil which was previously identified as Bacillus tequilensis based on 16S rDNA analysis. This study also aims to characterize the serine protease and its biocatalytic potentials implying a combination of empirical and in-silico approaches. Next generation sequencing and short read de novo assembly generated the 4,235,084 bp draft genome of Bacillus sp. ZMS-2. Genome sequence analysis by digital DNA:DNA hybridization (dDDH) and average nucleotide identity classified the isolate as Bacillus subtilis ZMS-2 (Bioproject ID: PRJNA691551). Genome annotation revealed 10 antibiotic resistance genes, 8 antibiotic/antifungal gene clusters and 25 genes encoding proteases including subtilisin E, an extracellular alkaline protease. This extracellular protease (ZMS-2 protease) was produced using a statistically optimized medium, purified partially and characterized as alkaline serine protease. The partially purified ZMS-2 protease (780 U/mL) showed a 21 mm zone of casein hydrolysis and dehaired goat skin by pulling out hair with roots. These catalytic potentials of ZMS-2 protease were further confirmed using scanning electron microscopy of casein beads and dehaired skin. The study concludes B. subtilis ZMS-2 as a potent producer of a protease with promising potentials of commercial importance.
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Bacillus subtilis , Péptido Hidrolasas , Bacillus subtilis/genética , Concentración de Iones de Hidrógeno , Serina Endopeptidasas/genética , SubtilisinasRESUMEN
Marine organisms are rich sources of enzymes and their inhibitors having enormous therapeutic potential. Among different proteolytic enzymes, serine proteases, which can be obtained from various marine organisms show a potential to biomedical application as thrombolytic agents. Although this type of proteases plays a crucial role in almost all biological processes, their uncontrolled activity often leads to several diseases. Accordingly, the actions of these types of proteases are regulated by serine protease inhibitors (SPIs). Marine SPIs control complement activation and various other physiological functions, such as inflammation, immune function, fibrinolysis, blood clotting, and cancer metastasis. This review highlights the potential use of serine proteases and their inhibitors as the new wave of promising drugs.
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Organismos Acuáticos/metabolismo , Serina Proteasas/metabolismo , Inhibidores de Serina Proteinasa/farmacología , Animales , Coagulación Sanguínea/efectos de los fármacos , Fibrinólisis/efectos de los fármacos , Humanos , Inflamación/tratamiento farmacológico , Inflamación/metabolismoRESUMEN
PURPOSE: Degenerative mitral stenosis (DMS) is an increasingly recognized cause of mitral stenosis. The goal of this study was to compare echocardiographic differences between DMS and rheumatic mitral stenosis (RMS), identify echocardiographic variables reflective of DMS severity, and propose a dimensionless mitral stenosis index (DMSI) for assessment of DMS severity. METHODS: This is a single-center, retrospective cohort study. We included patients with at least mild MS and a mean transmitral pressure gradient (TMPG) ≥4 mm Hg. Mitral valve area by the continuity equation (MVACEQ ) was used as an independent reference. The DMSI was calculated as follows: DMSI = VTILVOT / VTIMV. All-cause mortality data were collected retrospectively. RESULTS: A total of 64 patients with DMS and 24 patients with RMS were identified. MVACEQ was larger in patients with DMS (1.43 ± 0.4 cm2 ) than RMS (0.9 ± 0.3 cm2 ) by ~0.5 cm2 (P = <.001), and mean TMPG was lower in the DMS group (6.0 ± 2 vs 7.9 ± 3 mm Hg, P = .003). A DMSI of ≤0.50 and ≤0.351 was associated with MVACEQ ≤1.5 and MVACEQ ≤1.0 cm2 (P < .001), respectively. With the progression of DMS from severe to very severe, there was a significant drop in DMSI. There was a nonsignificant trend toward worse survival in patients with MVACEQ ≤1.0 cm2 and DMSI ≤0.35, suggesting severe stenosis severity. CONCLUSION: Our results show that TMPG correlates poorly with MVA in patients with DMS. Proposed DMSI may serve as a simple echocardiographic indicator of hemodynamically significant DMS.
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Estenosis de la Válvula Mitral , Ecocardiografía , Humanos , Válvula Mitral/diagnóstico por imagen , Estenosis de la Válvula Mitral/diagnóstico por imagen , Estudios Retrospectivos , Índice de Severidad de la EnfermedadRESUMEN
Emerging resistance to existing antimicrobial agents is one of the growing concerns and a serious problem for public health globally. Currently available antimicrobial agents are potent and effective but surfacing resistance to these drugs has not been ruled out so far. Therefore, it is utmost important to explore new bioactive compounds from natural sources to meet future needs. The present study was designed to produce, optimize, characterize and evaluate antimicrobial, fibrinolytic and anti-coagulant potential of a new alkaline protease. Proteolytic strain from desert soils of Tharparkar, Pakistan was subjected to 16S rDNA sequencing and identified as Bacillus tequilensis ZMS-2(Genbank Accession No. MK101013). During submerged fermentation at 37ºC, maximum enzyme production (454 U/ml) was observed with 24h old inoculum. The best incubation time was 72h (544 U/ml), optimum inoculum size and pH was 10% at pH 8 with 494 and 506 U/ml, respectively. The best carbon source was starch (571 U/ml), while ideal substrate was wheat bran (536 U/ml). Optimal temperature and pH for proteolytic activity was 60ºC (420 U/ml) and 8 (332 U/ml). Alkaline protease showed antibacterial activity against Staphylococcus aureus (27mm), Bacillus licheniformis (20mm), Klebsiella pneumoniae (17mm) and Escherichia coli (15mm). The strain B. tequilensis ZMS-2 also exhibited anticoagulant, fibrinolytic and dehairing potential suggesting application of its protease in various industries.
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Antiinfecciosos/farmacología , Anticoagulantes/farmacología , Bacillus/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/farmacología , Endopeptidasas/metabolismo , Endopeptidasas/farmacología , Fibrinolíticos/farmacología , Medios de Cultivo/metabolismo , Fermentación/fisiología , Concentración de Iones de Hidrógeno , Pakistán , TemperaturaAsunto(s)
Dolor en el Pecho/terapia , Puente de Arteria Coronaria/efectos adversos , Dolor Postoperatorio/terapia , Analgésicos/uso terapéutico , Disección Aórtica/complicaciones , Dolor en el Pecho/etiología , Dolor Crónico/terapia , Enfermedad de la Arteria Coronaria/complicaciones , Electrocardiografía , Humanos , Anamnesis/métodos , Dolor Postoperatorio/etiología , Examen Físico/métodos , Recurrencia , Derivación y Consulta , Fumar/efectos adversos , Esternotomía/efectos adversos , Infección de la Herida Quirúrgica/complicacionesRESUMEN
This paper presents cooperative routing scheme to improve data reliability. The proposed protocol achieves its objective, however, at the cost of surplus energy consumption. Thus sink mobility is introduced to minimize the energy consumption cost of nodes as it directly collects data from the network nodes at minimized communication distance. We also present delay and energy optimized versions of our proposed RE-AEDG to further enhance its performance. Simulation results prove the effectiveness of our proposed RE-AEDG in terms of the selected performance matrics.
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Due to the recent development in the field of Wireless Sensor Networks (WSNs), the Wireless Body Area Networks (WBANs) have become a major area of interest for the developers and researchers. Human body exhibits postural mobility due to which distance variation occurs and the status of connections amongst sensors change time to time. One of the major requirements of WBAN is to prolong the network lifetime without compromising on other performance measures, i.e., delay, throughput and bandwidth efficiency. Node prioritization is one of the possible solutions to obtain optimum performance in WBAN. IEEE 802.15.6 CSMA/CA standard splits the nodes with different user priorities based on Contention Window (CW) size. Smaller CW size is assigned to higher priority nodes. This standard helps to reduce delay, however, it is not energy efficient. In this paper, we propose a hybrid node prioritization scheme based on IEEE 802.15.6 CSMA/CA to reduce energy consumption and maximize network lifetime. In this scheme, optimum performance is achieved by node prioritization based on CW size as well as power in respective user priority. Our proposed scheme reduces the average back off time for channel access due to CW based prioritization. Additionally, power based prioritization for a respective user priority helps to minimize required number of retransmissions. Furthermore, we also compare our scheme with IEEE 802.15.6 CSMA/CA standard (CW assisted node prioritization) and power assisted node prioritization under postural mobility in WBAN. Mathematical expressions are derived to determine the accurate analytical model for throughput, delay, bandwidth efficiency, energy consumption and life time for each node prioritization scheme. With the intention of analytical model validation, we have performed the simulations in OMNET++/MIXIM framework. Analytical and simulation results show that our proposed hybrid node prioritization scheme outperforms other node prioritization schemes in terms of average network delay, average throughput, average bandwidth efficiency and network lifetime.
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This paper embeds a bi-fold contribution for Underwater Wireless Sensor Networks (UWSNs); performance analysis of incremental relaying in terms of outage and error probability, and based on the analysis proposition of two new cooperative routing protocols. Subject to the first contribution, a three step procedure is carried out; a system model is presented, the number of available relays are determined, and based on cooperative incremental retransmission methodology, closed-form expressions for outage and error probability are derived. Subject to the second contribution, Adaptive Cooperation in Energy (ACE) efficient depth based routing and Enhanced-ACE (E-ACE) are presented. In the proposed model, feedback mechanism indicates success or failure of data transmission. If direct transmission is successful, there is no need for relaying by cooperative relay nodes. In case of failure, all the available relays retransmit the data one by one till the desired signal quality is achieved at destination. Simulation results show that the ACE and E-ACE significantly improves network performance, i.e., throughput, when compared with other incremental relaying protocols like Cooperative Automatic Repeat reQuest (CARQ). E-ACE and ACE achieve 69% and 63% more throughput respectively as compared to CARQ in hard underwater environment.
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In this study, we analyse incremental cooperative communication for wireless body area networks (WBANs) with different numbers of relays. Energy efficiency (EE) and the packet error rate (PER) are investigated for different schemes. We propose a new cooperative communication scheme with three-stage relaying and compare it to existing schemes. Our proposed scheme provides reliable communication with less PER at the cost of surplus energy consumption. Analytical expressions for the EE of the proposed three-stage cooperative communication scheme are also derived, taking into account the effect of PER. Later on, the proposed three-stage incremental cooperation is implemented in a network layer protocol; enhanced incremental cooperative critical data transmission in emergencies for static WBANs (EInCo-CEStat). Extensive simulations are conducted to validate the proposed scheme. Results of incremental relay-based cooperative communication protocols are compared to two existing cooperative routing protocols: cooperative critical data transmission in emergencies for static WBANs (Co-CEStat) and InCo-CEStat. It is observed from the simulation results that incremental relay-based cooperation is more energy efficient than the existing conventional cooperation protocol, Co-CEStat. The results also reveal that EInCo-CEStat proves to be more reliable with less PER and higher throughput than both of the counterpart protocols. However, InCo-CEStat has less throughput with a greater stability period and network lifetime. Due to the availability of more redundant links, EInCo-CEStat achieves a reduced packet drop rate at the cost of increased energy consumption.
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Most applications of underwater wireless sensor networks (UWSNs) demand reliable data delivery over a longer period in an efficient and timely manner. However, the harsh and unpredictable underwater environment makes routing more challenging as compared to terrestrial WSNs. Most of the existing schemes deploy mobile sensors or a mobile sink (MS) to maximize data gathering. However, the relatively high deployment cost prevents their usage in most applications. Thus, this paper presents an autonomous underwater vehicle (AUV)-aided efficient data-gathering (AEDG) routing protocol for reliable data delivery in UWSNs. To prolong the network lifetime, AEDG employs an AUV for data collection from gateways and uses a shortest path tree (SPT) algorithm while associating sensor nodes with the gateways. The AEDG protocol also limits the number of associated nodes with the gateway nodes to minimize the network energy consumption and to prevent the gateways from overloading. Moreover, gateways are rotated with the passage of time to balance the energy consumption of the network. To prevent data loss, AEDG allows dynamic data collection at the AUV depending on the limited number of member nodes that are associated with each gateway. We also develop a sub-optimal elliptical trajectory of AUV by using a connected dominating set (CDS) to further facilitate network throughput maximization. The performance of the AEDG is validated via simulations, which demonstrate the effectiveness of AEDG in comparison to two existing UWSN routing protocols in terms of the selected performance metrics.
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Redes de Comunicación de Computadores , Modelos Teóricos , Tecnología Inalámbrica , Algoritmos , Océanos y MaresRESUMEN
As players and soldiers preform strenuous exercises and do difficult and tiring duties, they are usually the common victims of muscular fatigue. Keeping this in mind, we propose FAtigue MEasurement (FAME) protocol for soccer players and soldiers using in-vivo sensors for Wireless Body Area Sensor Networks (WBASNs). In FAME, we introduce a composite parameter for fatigue measurement by setting a threshold level for each sensor. Whenever, any sensed data exceeds its threshold level, the players or soldiers are declared to be in a state of fatigue. Moreover, we use a vibration pad for the relaxation of fatigued muscles, and then utilize the vibrational energy by means of vibration detection circuit to recharge the in-vivo sensors. The induction circuit achieves about 68 % link efficiency. Simulation results show better performance of the proposed FAME protocol, in the chosen scenarios, as compared to an existing Wireless Soccer Team Monitoring (WSTM) protocol in terms of the selected metrics.
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Redes de Comunicación de Computadores/instrumentación , Fatiga/diagnóstico , Tecnología de Sensores Remotos/instrumentación , Telemedicina/instrumentación , Tecnología Inalámbrica/instrumentación , Algoritmos , Atletas , Humanos , Personal Militar , Fútbol/fisiologíaRESUMEN
Performance enhancement of Underwater Wireless Sensor Networks (UWSNs) in terms of throughput maximization, energy conservation and Bit Error Rate (BER) minimization is a potential research area. However, limited available bandwidth, high propagation delay, highly dynamic network topology, and high error probability leads to performance degradation in these networks. In this regard, many cooperative communication protocols have been developed that either investigate the physical layer or the Medium Access Control (MAC) layer, however, the network layer is still unexplored. More specifically, cooperative routing has not yet been jointly considered with sink mobility. Therefore, this paper aims to enhance the network reliability and efficiency via dominating set based cooperative routing and sink mobility. The proposed work is validated via simulations which show relatively improved performance of our proposed work in terms the selected performance metrics.
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Appropriate network design is very significant for Underwater Wireless Sensor Networks (UWSNs). Application-oriented UWSNs are planned to achieve certain objectives. Therefore, there is always a demand for efficient data routing schemes, which can fulfill certain requirements of application-oriented UWSNs. These networks can be of any shape, i.e., rectangular, cylindrical or square. In this paper, we propose chain-based routing schemes for application-oriented cylindrical networks and also formulate mathematical models to find a global optimum path for data transmission. In the first scheme, we devise four interconnected chains of sensor nodes to perform data communication. In the second scheme, we propose routing scheme in which two chains of sensor nodes are interconnected, whereas in third scheme single-chain based routing is done in cylindrical networks. After finding local optimum paths in separate chains, we find global optimum paths through their interconnection. Moreover, we develop a computational model for the analysis of end-to-end delay. We compare the performance of the above three proposed schemes with that of Power Efficient Gathering System in Sensor Information Systems (PEGASIS) and Congestion adjusted PEGASIS (C-PEGASIS). Simulation results show that our proposed 4-chain based scheme performs better than the other selected schemes in terms of network lifetime, end-to-end delay, path loss, transmission loss, and packet sending rate.
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Tecnología de Sensores Remotos , Agua , Tecnología Inalámbrica , Algoritmos , Comunicación , Simulación por Computador , Modelos TeóricosRESUMEN
BACKGROUND: Lead erosion is one of the troublesome complications which are very difficult to treat and most of the time leads to device explanation and replacement prematurely. METHODS: From 2005 to 2011, total 415 pacemakers were implanted in our cardiology department at Hayatabad Medical Complex Peshawar. The patients were followed regularly at six month interval or more frequently in case there were complications. At every visit we inspected the wound site, electrocardiography was done and device was analyzed with compatible programmer for the device. If there was soreness at the site of implantation, patient was seen more frequently and if there was erosion of skin, wound was reopened margin refreshed and wound closed. Initially we closed the wound in two layers after reopening but we got repeated erosion with this method and so we buried the leads sub-muscularly as change strategy which again proved unsuccessful. Results: During the six years study about 415 permanent pacemakers were implanted. During this time period, we received: three lead erosion, which were repositioned. There were recurrence in two cases and they were again subjected to procedure with a change strategy; by burying the leads in muscles, which proved unsuccessful. CONCLUSION: Leads erosion can be prevented by carefully burying leads in three layers first in muscle followed by subcutaneous tissue and then closing the wound by suturing the skin during initial implantation.