Iris Publishers-Open access Journal of Cardiology Research & Reports | How to Combat the Pandemic of Cardiovascular Disease? Vegetable Alpha-Linolenic Acid or Omega-3 “Fish Oil” EPA & DHA

 

Authored by Dr.Dr.Ir. Vincent van Ginneken*

Abstract

There are currently two main directions with regard to nutritional supplements with PUFAs. The first research school recommends enriching the diet with the essential fatty acid (EFA) obtained from vegetable sources, the C18 lipid omega-3 molecule α-linolenic acid and then via the elongase/ desaturase activity naturally in omega-3 Eicosapentaenoic acid (EPA) and omega-3 Docosahexaenoic acid (DHA). The second research school says that the diet should be immediately enriched with EPA and DHA, obtained directly from fish oil. Here we want to investigate the controversies about the possible use of these FAs as preventive / curative instruments against the development of CVDs to combat the current pandemic of heart disease through nutritional intervention. We calculated from the [product] / [precursor] ration in the Cholesteryl (ChE) fraction the enzymatic activity of elongase/desaturase activity of the heart muscle of a juvenile high-fat-induced C57bl6 mouse model, which model we previously used in CVD studies. The main conclusion is that the omega-3 route from α- linolenic acid to EPA and DHA does not exist enzymatically in the heart and that the best strategy for preventing CVDs is direct diet enrichment with EPA and DHA. Because CVDs are currently the number one cause of death in the US and the WHO predicts that especially in the coming decades developing countries will be affected by this pandemic of CVDs. Research should focus on the underlying mechanism of omega-3 PUFA protection.

Keywords: Cardiovascular diseases; Heart; Metabolic syndrome; LC-MS; Lipidomics; Essential fatty acid (EFA); α-linolenic acid; Elongase/ desaturase activity; Eicosapentaenoic acid (EPA); Docosahexaenoic acid (DHA); Fish oil; C57bl6 mouse model

Introduction

Very recently, in the Lancet of October 7, 2019 [1], the WHO published projections about the pandemic of cardiovascular disease (CVDs) that currently plague the world population, resulting in 2030 with 22.2 million deaths a year [2]. In the past three decades, numerous epidemiological and observational studies have been published on the prevention of CVD and the benefits of diet enrichment with polyunsaturated fatty acids (PUFAs) [3]. There are currently two main directions with regard to nutritional supplements with PUFAs. The first research school recommends enriching the diet with the essential fatty acid (EFA) obtained from vegetable sources, the C18 lipid omega-3 molecule α-linolenic acid and then via the elongase/desaturase activity naturally in omega-3 Eicosapentaenoic acid (EPA) and omega-3 Docosahexaenoic acid (DHA) [4]. The second research school says that the diet should be immediately enriched with EPA and DHA, obtained directly from fish oil [5]. Here we want to investigate the controversies about the possible use of these FAs as preventive / curative instruments against the development of CVDs to combat the current pandemic of heart disease through nutritional intervention. We calculated from the [product] / [precursor] ration in the Cholesteryl (ChE) fraction the enzymatic activity of elongase/desaturase activity of the heart muscle of a juvenile high-fat-induced C57bl6 mouse model, which model we previously used in CVD studies [6,7]. The main conclusion is that the omega-3 route from α-linolenic acid to EPA and DHA does not exist enzymatically in the heart and that the best strategy for preventing CVDs is direct diet enrichment with EPA and DHA. Because CVDs are currently the number 1 cause of death in the US [8] and the WHO predicts that especially in the coming decades developing countries will be affected by this pandemic of CVDs [1]. Research should focus on the underlying mechanism of omega-3 PUFA protection.

Epidemiology Versus Lipidomics Enzymatic Conversion

Currently, more than 1/3 of the world’s population is obese (Body Mass Index, BMI> 30) [9]. As a result, cardiovascular disease and stroke are currently the largest killer in the US. Every year more than 2 million Americans suffer from a heart attack or stroke and more than 800,000 die. CVDs are the leading cause of death in the United States and the biggest cause of lower life expectancy among black African Americans [10]. The confluence of many westernizing factors has led to a worldwide increase in fat consumption in the US, which is partly due to an increased consumption of fast food. Total added fat intake increased from 57 to 66 pounds / person from 1980 to 1997 [11]. Thus, there is a close link between obesity morbidity and fat consumption as shown in (Figure 1) for the US.

We recently conducted a study to systematically identify the cause of cardiovascular disease (CVD) related to the high-fat diet (HFD) in a juvenile insulin resistant (IR) C57bl6 mouse model [7] according to a system biology [12] Lipidomics-based approach [13]. We have used LC-MS techniques to determine the 7 most important lipid classes: the lyso-phosphatidylcholines (LPC), phosphatidylcholines (PC), Sphingomyelins (SPM), Diacylglycerols (DG), phosphatidylethanolamines (PE), Triacylglycerols (TG) and Cholesteryl -esters (ChE) as previously performed [6,7]. The HFD had an extremely high TG content of 633.4% increase based on lard (P <0.0001***). Effects of the high-fat diet can be seen on the heart muscle, where the TG level increased by 278% (P≤ 0.029*) compared to the control chow diet, resulting in lipo-toxicity related to hypoxic disorders. So, our main conclusion in that recent study was that lipo-toxicity due to excessive TGs accumulation, resulting in hypoxic disorders, was the leading cause of CVD [7]. From various studies there are indications that increasing the amount of polyunsaturated fatty acids (PUFAs) that we eat can lower our cholesterol levels in the blood and give us less chance of cardiovascular disease, especially if PUFAs are eaten instead of saturated fats, e.g. fats from animal dairy sources such as meat and cheese [14,15]. From such epidemiological studies, hard statements such as: “Replacing 5% of energy intake from dairy fat with equivalent energy intake from polyunsaturated fatty acids (PUFA) has been linked to a 24% lower risk of cardiovascular disease (CVD)”, have been made [16].

But it is our perception, interpretation, and major disadvantage of such epidemiological studies - based primarily on systematic review and meta-analysis of prospective cohort studies - that there are many confusing factors that can ‘fail’ the outcomes and conclusions of such a study. Secondly, PUFAs is a large hub of fatty acids (FAs) (Figure 2), starting with the two essential fatty acids (EFAs) LA and ALA which then end up with a complex enzyme conversion pattern in the elongase-desaturase array important ‘fish oils’ EPA and DHA. LA and ALA are of vegetable origin, while EPA and DHA are obtained from fish oil or fish capsules. The most evidence for the benefits of PUFAs is obtained from Eicosapentaenoic acid (C20: 5, ω-3; EPA) and Docosahexaenoic acid (C22: 6, ω-3; DHA), the ‘fish oil’ such as fat with long chain acids (FAs) in this family. However, there is some epidemiological support for an advantage of the EFA α-linolenic acid (C18: 3, ω-3; ALA), the plant-based precursor of EPA for CVDs [17]. The American Heart Association (AHA) has currently approved the use of ω-3 PUFAs in a dose of approximately 1 g / day of combined DHA and EPA, either in the form of fatty fish or fish oil supplements (in capsules or liquid form) in patients with documented coronary artery disease (CHD) [5]. In the past three decades, numerous epidemiological and observational studies have been published on the benefits of CVDs from omega-3 PUFAs, to mention a few studies: [18-20]. Because cardiovascular diseases and strokes are number 1, it is important to have clear guidelines at the population level with regard to supplementing the diet with PUFAs.

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Iris Publishers-Open access Journal of Cardiology Research & Reports | Comparative Analysis of His Bundle Versus Septal Versus Right Ventricuar Apical Pacing- A Short Term Follow up Study

 

Authored by Sudeb Mukherjee*

Abstract

Introduction: His Bundle Pacing (HBP) is devoid of consequences of remodelling induced by Right Ventricular Apical Pacing (RVAP). Septal pacing has also been studied in several studies. Complications of heart failure, chamber dilatation and QRS prolongation are not seen in HBP and less in septal pacing. This study was done to evaluate outcomes of HBP versus Septal pacing versus RVAP in those patients requiring pacing.

Methods:

Total 100 patients with atrio ventricular block with syncope who required pacing were included in this study. 50 patients underwent RVAP, 38 patients septal pacing and 12 patients underwent His bundle pacing. Detail echocardiogram-based parameters were obtained before and post pacing 6 months. All data collected appropriately and analysed accordingly using SPSS software by 1-way ANOVA with the use of the Holm-Sidak method for pairwise multiple comparisons or by the χ2 test, as appropriate. The statistical test of main treatment effect was an adjusted F test with Kenward-Roger type adjustment of denominator degrees of freedom.

Results: HBP was associated with improvements in Left Ventricular Ejection Fraction (LVEF) and other chamber dimension which was statistically significant. Septal pacing was found to be better (not statistically significant although numerically better) compared to RVAP group which showed deterioration of LVEF, chamber dimension and QRS duration.

Conclusion: HBP was found to be more physiological than septal and RVAP group although technically challenging and required expertise.

Keywords: His Bundle Pacing (HBP); Septal pacing; Right Ventricular Apical Pacing RVAP); Left Ventricular Ejection Fraction (LVEF)

Introduction

The cardiac conduction system is a collection of nodes and specialised conduction cells that initiate and co-ordinate contraction of the heart muscle. It consists of sinoatrial (SA) node, atrioventricular (AV) node, atrioventricular bundle (bundle of His) amd purkinje fibres. The sequence of electrical events during one full contraction of the heart muscle starts from SA node spreads across the atria to the AV node, into the bundle of His, down the interventricular septum and via the Purkinje fibres spread along the ventricles, causing them to contract. This rapid conduction allows coordinated ventricular contraction (ventricular systole) and blood is moved from the right and left ventricles to the pulmonary artery and aorta respectively [1-3]. Since the era of Hippocrates (460-375BC) physicians were aware of syncope. Innovative works by different scientists at different times enriched the history of pacemakers gradually. It started from McWilliam [4] to Lidwell (who developed first external pacemaker) [5] to Hyman’s device (used DC current through a bipolar needle electrode) and finally to Zoll [6] who modernized the concept of pacing radically. Over the time through the hand of Earl E. Bakken the first battery-operated wearable pacemaker came into availability later that year for the treatment of heart bloc [7-9]. Microprocessor-driven pacemakers appeared in around 1990. These became very complex devices capable of detecting and storing events utilising several algorithms. The rate-response pattern also adjusted itself automatically to the patient’s activity level.

From the first human implantation the right ventricular (RV) apical pacing has saved millions of lives, but within one decade it was proved to be non-physiological as several deleterious hemodynamic effects were noted during follow up [10]. Chronic RVAP causes left ventricular dilatation and reduction of left ventricular ejection fraction [11]. During RVAP the conduction of the electrical wave front propagates through the myocardium, rather than through the His-Purkinje conduction system as a result the electrical wave form propagates more slowly and induces heterogeneity in electrical activation of myocardium comparable to left bundle branch block [12]. Left ventricular diminished dp/dt changes (pressure changes) has also been found with chronic RVAP [13]. Decrease in contractile sate of LV myocardium leading to LV systolic dysfunction has also been noted in several studies. Subcellular anatomical changes have also been demonstrated in several previous studies that includes various histopathologic abnormalities in paced patients. Histopathological alterations in biopsy samples following pacing include myofiber variation, fibrosis, fat deposition, sclerosis, and mitochondrial morphological changes [14]. Unfavourable effects of right ventricular (RV) pacing include ventricular remodelling, dilation, elevated diastolic filling pressure, increased functional mitral regurgitation, myocardial perfusion defects, and reduced LV ejection fraction. Of all ventricular sites, the RV apex seems to be the most hemodynamically unfavourable [15]. Right ventricular apical pacing (RVAP) has been shown to increase morbidity and mortality in patients receiving a high percentage of cumulative pacing [16]. All these factors lead to search for alternative pacing site. Various alternative pacing sites has been explored that includes Right Ventricular Outflow Tract pacing, Septal Pacing, Biventricular Pacing, Atrial Pacing, Dual Pacing and His Bundle pacing.

Septal pacing

The idea of septal pacing is based on the fact that the septal region of the RVOT and mid RV are the first zones of the ventricle to depolarise, suggesting that pacing from these areas on the right side of the septum would achieve as normal a contraction pattern as possible.

Evolution of his bundle pacing

The term ‘physiological’ was used in Canadian Trial of Physiological pacing (CTOPP) to reflect the terminology at the time of development of the trial [17]. However atrial pacing was considered physiological at that time. Later it was thought that pacing the atrium and ventricle sequentially may solve the problem of unsynchronised contraction and prevent atrial bradycardia but the ventricular activation sequence is clearly not physiological. Studies using biventricular pacing have suggested improvement in patients of left bundle branch block. The dual chamber and VVI implantable defibrillator (DAVID study) randomised patients receiving implantable defibrillators (ICD) either to backup pacing at the rate of 40 bpm or to DDDR pacing at the at the rate of 70 per minutes. The composite end point of death or hospitalisation with heart failure was greater in the group receiving DDDR pacing than in the back up pacing group [18]. There was a very similar benefit with regard to reduction of atrial fibrillation and a significant but weak benefit with regard to hospitalisation for heart failure. Two probable solutions to this problem are: first involves manipulation of pacing modes and timing cycle operation among patients with reliable atrio-ventricular conduction to minimise unnecessary ventricular pacing and preserve normal ventricular conduction and the second involves pacing at alternative ventricular site to attenuate the adverse effects imposed by ventricular desynchronization when ventricular pacing can’t be avoided.

The main purpose of permanent cardiac electrostimulation is to maintain an adequate cardiac rhythm, trying to restore the physiology of the normal excito-conductive physiology of the heart as much as possible. Up until now, importance had been given to two elements that were considered fundamental for physiological pacing: maintenance of the atrioventricular Sequence and the rateresponsive function. If the aim is to mimic physiological activation patterns, the HBP may provide the ideal site. During the last several years there was much work done in the field of DHBP, to extend the indications and to improve the technique. Here in this study the comparative analysis among RVAP, His Bundle Pacing and Septal pacing has been done.

Objective

To find out outcomes of different parameters in 3 different types of pacing, His bundle vs Septal vs RV Apical in selected group of patients. This was a short term follow up study with detail analysis in respect of various parameters mentioned below.

1. To look for ECG QRS duration shortening.

2. To look for Left ventricular Ejection Fraction (LVEF) immediately, after 1 month and after 6 months.

3. To look for Left ventricular Internal Diameter (LVIDD) change at 1 month and at 6 months.

4. To look for Tricuspid Regurgitation (TR) in different group of pacing.

5. To assess biochemical parameters in different groups following pacing.

LV dimensions were measured from the parasternal long-axis M-mode and expressed as Z scores with the use of weight-related normal limits. LV shortening fraction was calculated.

LV volumes were measured from the apical 4- and 2-chamber views with the Simpson biplane method. LV ejection fraction (EF) was calculated and graded as follows: normal

(LV EF ≥55%), subnormal (LV EF <55%), and significantly decreased (LV EF <45%)

Methods

All patients with atrio ventricular block presented/admitted to IPGME&R Hospital in the department of cardiology were included in this study. It was an prospective observational study for total patients of, who were followed for 6 months and all details parameters were documented and analysed accordingly.

Inclusion criterias

For HBP: Only patients who met the following inclusion criteria were considered candidates for permanent HBP:

a) Indication of permanent pacing for AV conduction disturbance or left ventricular resynchronization not possible via the coronary sinus.

b) Potential for elimination of AV block or bundle-branch block by HBP, leading to a narrow QRS complex (120 ms).

c) Maximum hisian capture threshold of 2.5 V/1 ms.

d) 1:1 His-ventricular conduction at a minimum pacing rate of 120 b.p.m.

d) 1:1 His-ventricular conduction at a minimum pacing rate of 120 b.p.m.

B. Potential for elimination of AV block or bundle-branch block (LBBB) by HBP, leading to a narrow QRS complex (120 ms).

For RVAP pacing: For all other patients needed pacing included in this category.

Exclusion criterias

For HBP and Septal Pacing:

1. Complete Heart Block.

2. Wide Complex Tachycardia during any episode before and after admission.

Parameters used

Echocardiographic criterias: 1)Left Ventricular Internal Dimension in Systole and Diastole (LVIDs, LVIDd), 2)Left Ventricular Posterior Wall Thickness (LVPWD), 3)Left Ventricular Ejection Fraction (LVEF), 4) Left Atrial Diameter 5) Right Atrial Diameter 6) Right Ventricular Diameter 7) Tricuspid Regurgitation (TR).

Electrocardiographic criterias: QRS duration, QRS morphology.

Blood investigations: N-Terminal pro Brain Natriuric Peptide.

Study technique: Patients of all ages are going to be included in this study. So, after taking a valid consent from the patients, a detailed history and clinical examination was carried out.

HBP: Procedure HBP was performed using the Medtronic pacing lead delivered through a fixed curve sheath. The delivery sheath was inserted into the right ventricle beyond the tricuspid annulus over a guide wire through left cephalic or axillary vein. Subsequently, the pacing lead was advanced through the sheath such that only the distal electrode /screw is beyond the tip of the catheter. A unipolar electrogram was recorded from the lead tip at again setting of 0.05mV/ mm and displayed on a Medtronic pacing system. The preformed double curve of this catheter points the tip toward the superior AV septum. An HB electrogram was identified by mapping the AV septum. The lead was then screwed in this position by means of 4–5 clockwise rotations. The HB capture threshold was assessed and accepted if found to be 2.5 V at 1.0 ms. If an acceptable HB capture could not be achieved after 5 attempts at lead positioning or a fluoroscopy duration of 30 minutes ,the lead was then placed in the RV mid-septum.

RVAP: RV leads were implanted in a standard fashion at the RV apex . Traditional tined-tip pacing to anchor a lead in the RV apex in those group of patients.

Septum: Septal pacing was done by the methods as described by Mond et, al. Under fluoroscopic imaging in the right anterior oblique view of 30 degrees, the RV was divided into 3 zones as follows: (1) an upper zone (one-third from the top of the RV) between the pulmonary artery bulge and the roof of the tricuspid valve; (2) a middle zone; and (3) a lower zone (one-third from the bottom of the RV). Then, the ventricular lead was anchored in the middle zone of the RV. After fixation of the ventricular lead, the left anterior oblique view of 45 degrees was used to confirm that the lead was successfully placed on the RV septum and not the free wall. Surface and device electrocardiography, and echocardiograpic examination studies were done by be performed at 24 hours after pacemaker implantation using a Vivid 7 Dimension ultrasound machine (GE Healthcare) with an M4S probe and again at 6 months. Echocardiographic parameters were recorded immediately after 1 months and after imlantaton and again at 6 months.

Analysis of data

All data collected appropriately and analysed accordingly. SPSS software latest version was used for demographic as well as objective analysis. ANOVA was done and analysed properly. Continuous data are presented as raw means (SDs). Differences in demographic and informative variables between pacing sites were evaluated by 1-way ANOVA with the use of the Holm-Sidak method for pairwise multiple comparisons or by the χ2 test, as appropriate. The continuous outcome variables characterizing LV function and synchrony were analysed with the use of a linear mixed model approach. Each model included the set of clinically informative additive covariates in addition to the main factor tested. The continuous covariates included age at implantation pacing duration, and QRS duration. The statistical test of main treatment effect was an adjusted F test with Kenward-Roger type adjustment of denominator degrees of freedom.

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Iris Publishers-Open access Journal of Biomedical Engineering & Biotechnology | Biotechnology and Bioengineering Tools in COVID-19 Diagnostics - CRISPR and Beyond

 

Authored by Rwik Sen*

Mini Review

Advances in bioengineering and biotechnology are an urgent need of the hour because of the ongoing pandemic of COVID-19. Coronavirus disease 2019 or COVID-19 is caused by SARS-CoV-2 which is a strain of a coronavirus called SARS-CoV or Severe Acute Respiratory Syndrome Corona Virus. Globally, COVID-19 has claimed lives 1,575,810 and infected 69,239,671 people. In this direction, biotechnological and bioengineering endeavors have shown several promising results to control the pandemic, which are discussed in this mini review.

Worldwide governments are aiming for COVID-19 testing to available on a large-scale. COVID-19 diagnostics include detection based on antibodies and nucleic acids, which are the most prevalent forms of COVID-19 testing. Nucleic acid-based tests involve sample collection from nasopharyngeal, oropharyngeal, or respiratory regions are collected and subjected to RT-PCR (Reverse Transcriptase PCR) [1]. In this process, SARS-CoV-2 RNA is converted to cDNA (complementary DNA), then primers specific to 3 loci of the viral cDNA are used for amplification [2]. The loci are ORF1ab which is the open reading frame of viral RDRP or RNA-Dependent RNA Polymerase, envelope protein or E gene, and nucleocapsid or N gene (Verma 2020). Either a singleplex or a multiplex format of RT-PCR is used.

A frequent problem reported in COVID-19 testing is falsenegatives, hence complementation of RT-PCR with CT scans is recommended for efficient diagnosis of SARS-CoV-2 infection [3,4]. An improved and efficient version of RT-PCR testing of COVID-19 is the targeting of RdRp/helicase (Hel), spike (S), and nucleocapsid (N) genes of SARS-CoV-2 [5].

In antibody-based testing of COVID-19, immunoglobulins IgG, IgM, and IgA are probed by ELISA (Enzyme-Linked ImmunoSorbent Assay). These immunoglobulins are produced by the body as a defense response to viral entry and detected after different number of days following COVID-19 infection [2]. In addition to diagnostics, several groups have generated panels of antibodies against spike or S protein of SARS-CoV-2 which binds to human receptor ACE2 [6]. The antibodies neutralize S protein, hence preventing viral infection.

Another biotechnological advancement of COVID-19 testing is done by CRISPR-based methods where SARS-CoV-2 DNA Endonuclease-Targeted CRISPR Trans Reporter (DETECTR) uses CRISPR-Cas12 to detect COVID-19 [7]. Another COVID-19 detection process based on CRISPR uses recombinase-mediated polymerase pre-amplification of DNA or RNA which is a specific high-sensitivity enzymatic reporter unlocking (SHERLOCK) [8]. More methods based on CRISPR are developed to overcome the disadvantages of existing CRISPR-based tools for COVID-19 diagnosis.

In addition to the methods discussed above, there are other processes for COVID-19 diagnostics. Overall, a combination of biotechnological and bioengineering advances has led to the development of diagnostic and therapeutic interventions for COVID-19. Further research is needed to make them available to populations globally in a rapid, efficient, and inexpensive way to combat the pandemic.

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Iris Publishers-Open access Journal of Current Trends in Civil & Structural Engineering | Preparations of LNG Bunkering Facilities in the United States

 

Authored by Pengfei Zhang*

Highlights of this Article

a. LNG as the alternative energy that can substitute crude oils to reduce carbon emissions.

b. Characteristics of LNG that are greener, flexible and cheaper compared to conventional fuels.

c. The market demand of LNG globally and in the United States that concludes the trends of modifications for LNG bunkering facilities in Northern America.

d. Regulations required by United States LNG bunkering facilities to operate the safest and efficient LNG transferring procedures.

Abstract

Following the good news of the Liquefied Natural Gas (LNG) market booming, the United States (US) is preparing its best to be the major and effective LNG supplier. Due to this demand, the LNG market is appealing not only to the US but to Australia as well since the country is also one of the largest LNG producers in the world [1]. According to the US Energy Information Administration (EIA), the demand has been growing globally as natural gas will become the gas of alternative energy. To fulfill this demand, the US economic interest becomes targeted on the Liquefied Natural Gas (LNG) import terminals installation specifically in the country’s northern region. In viewing the growing LNG market, LNG bunkering facilities in Northern America are preparing expenses to modify their terminals in smoothing the LNG transferring process. Thus, this paper explores the preparations of LNG bunkers in Northern America with some LNG facilities that are included to show the preparations of the US in becoming the major exporter of LNG globally.

Keywords: Liquefied natural gas (LNG); Bunkering; Facilities; United states

Introduction

In recent years, the energy demand has been satisfied largely by the consumption of fossil fuels like petroleum, natural gas and coal. These fossil fuels have coated the 87% of US energy demand during the last decade [2]. During the last century, the US has exported natural gas via pipeline to Canada and Mexico. The quantity of natural gas exported has been less than imported. The only LNG export terminal of domestic production that has been operating since 1969 is the Kenai LNG Plant situated in Alaska which still in use for exporting LNG primarily to Japan. By 2000, the US was committed to a consolidation method of supply the natural gas demand by importing LNG. Forecasting reports given in 1999 by the Energy Information Administration (EIA) stated that natural gas imports were progressing to growth from 12.9% to 15.5% from 1997 to 2020 [3]. Based on these reports, five new LNG import terminals were designed, and some other existing facilities went through growth modifications. However, the mass production of natural gas throughout the last decade has changed the economic interests of the American business. The natural gas surplus has been encouraged by the progress on drilling technologies like “fracking”, which have simplified the extraction method of this natural resource. As the result of the fast growth of domestic natural gas production, most of the prevailing import facilities became unproductive. According to the most recent forecast studies performed by the EIA, the US will be positioned in the third position of the largest liquefaction capacity by 2020 after Australia and Qatar [3]. Around 50 permit applications for the development of recent LNG export terminals, or for the modification of existing import terminals are received in January 2015. Four of the applications are approved and some already under construction which is aligned to integrate liquefaction facilities to the already existing import terminals, which are better-known as brownfield projects. Brownfield refers to land within the United States that was used before for an industrial or commercial purpose and potentially contains dangerous waste or pollution in the current times [4].

Methods

The research approach conducted in this thesis will work as a framework to analyse the preparations of LNG bunkering facilities in Northern American. Broadly, this dissertation will focus on three investigation areas where the first area of focus will be the quantitative aspect of LNG market by globally and in the US. While the second area will be using qualitative to see the planned facilities in US LNG bunkering and the regulations required to be followed by the facilities’ operators. Furthermore, quantitative researchers highlight the analysis and measurement of causal relationships between variables, not processes. The derived result of the quantitative analysis will provide an objective conclusion whether the source of natural gas in US may be viable or not in an economic sense. The result of using qualitative analysis is to examine the development planned by US government to expand the growth of US LNG bunkering from its facilities perspectives. In contrast to the investment made by well-known companies as stated in Chapter 4, this research will show some explanations for each project as it describes the procedures and expected productions of LNG. The information was collected from web sources about LNG facilities in Northern America for examples ABS, USCG and EIA. These web sources are the most used sites for the maritime industry in the US that provide important and knowledgeable information. EIA includes both qualitative and quantitative data and is used mainly in both descriptive and explanatory research [5] for the LNG market in the US. While ABS, the website provides qualitative data where it shows the research and projects of LNG bunkering facilities in Northern America. The qualitative data also retrieved from USCG where the web source prepared the regulations for the operators at LNG bunkering facilities. The limitations of this research are the study is only focused on LNG bunkering operations from storage stranded and vehicle fueling perspective but not including other facilities for the development of LNG bunker in Northern America. Moreover, analysis collected only covers infrastructure required of LNG bunker facility in Northern America and does not include any necessary infrastructure of LNG bunker facility in the whole United States.

LNG Characteristics and the Market Analysis

Characteristics of LNG

LNG is a natural gas that has been cooled to the point that it combines to be fluid, which happens at a temperature of approximately -162°C (Celsius) in atmospheric pressure. Natural gas is transformed into liquid form through liquefaction procedure to empower transportation over long distances particularly, where the distribution pipelines are most certainly not viable or different limitations exist. When petroleum gas is changed over to LNG, the volume is diminished by a factor of 610 and it allows transportation and storage in huge volumes [6] (Figure 1).

Natural gas is a blend of different hydrocarbon gas known in scientific names for examples propane, methane, butane and ethane. Based on Figure 1 above, more than 80% of natural gas is shaped by methane which is the main element. To increase as much as the use, natural gas must be extracted. The particles can be separated from the gas via the natural gas processes at the gas partition plants. Each of the particles has a broad variety of uses [7]. With every other particle that exists, LNG has characteristics that make it special. These characteristics also relying on its area or region. The usual characteristics for LNG are:

1. Colorless;

2. Odorless;

3. Non-toxic but can cause asphyxiation in unventilated areas;

4. Non-corrosive cryogenic liquid at atmospheric conditions;

5. The density is in the range of 430-470 kg/m3 (Kilogram per Cubic Meter), depending on its composition;

6. LNG is normally kept at the atmospheric pressure less than 5 PSI gauge and

7. It has a boiling point of -162°C (Source: Mokhatab et al. [18]).

LNG prices

The supply chain and reserve of LNG make the cost competitive [9]. In Europe, the supply of gas by pipeline gives more competitive costs compared with imports by vessels while the LNG supply facilities are ending up more liberalized (IMO 2016). Fuel costs is a factor that can radically influence the LNG prices [10]. Fuel costs is an unstable market, and the difference in prices has a huge effect on profits that are made by bunkering firms. This will decide the payback time for the investments made by the bunkering organizations [11]. Currently, there is no regular international pricing tools for natural gas and as a result, regional gas prices differ globally as shown in Figure 2 below. However, there are tools that are utilized to provide competitive market, regulated and oillinked pricing. Oil-linked pricing connects natural gas in trading to long-term oil prices with the regulated prices established by governments and specific discount. While for the competitive pricing, it provides trading points to be used by consumers and suppliers to decide the value [12] (Figure 2).

Based on Figure 2 above, the utilization of different price mechanisms globally produces problems and conducts to improving international trade to use arbitrage opportunities. This forces on suppliers and customers to adjust their costs with traded markets. Even though there is vulnerability to the future price system that will continue, both World Energy Council (WEC) and USEIA predict that the competitive natural gas market will ultimately control the market [12]. In addition, these organizations also observed that natural gas prices have separated from petroleum fuels which it might not affect the LNG price. Different areas of Europe and Northern America are focusing on progress towards competitive approach. Moreover, it is predicted that Asia also likewise to acquire the similar approach [13].

LNG market in the united states

Based on Figure 3 above, the USEIA estimates that the total US technically retrievable dry natural gas capacity is 2,277tcf (Trillion Cubic Feet). EIA has calculated the integrated progressive US domestic utilization and LNG exports from 2015 to 2040 indicate less than 40 % of this resource. Moreover, EIA has estimated the accessible resource is stable [14]. Industry calculates that the US natural gas resources at the base are usually higher. US has sufficient natural gas to provide each local utilization and LNG exports into longer term without any problems. The ICF International estimated of 4,234tcf which means 85% bigger [3]. Moreover, US also provided natural gas without vulnerable by LNG export quantities are projected into EIA’s Annual Energy Outlook (AEO) 2016 Reference Case Study.

The benefits of the united states lng exports

(Figure 4) Exporting natural gas creates a variety of advantages to the United States. Based on Figure 4 above, it shows that under a several of export situations, most of the growth in LNG exports are supported by increased domestic output instead of reductions in domestic demand. Growing natural gas production supports thousands of extra jobs. An IHS report predicts that for every 1 BCF/D (Billion Cubic Feet per Day) of shale gas production, the economy is supported by some 32,000 total jobs (IHS Report 2013). In addition, LNG exports may contribute the maximum amount as $10 billion to $31 billion per state to the economies of natural gasproducing states [15]. Moreover, non-natural gas producing states also can take the benefits in growing demand for cement, steel, equipment and other product. Generally, varied studies have found that higher levels of LNG exports can provide economic gains for the United States [14]. Exports can give advantages to the US in the manufacturing sector. Expanding in natural gas production brings up in LNG that can be used as organic petrochemical feedstocks. ICF International analysed the effects of LNG exports and found out that NGL volumes will increase between 138,000 and 555,000 BPD (Barrels Per Day) by 2035 [3]. According to ICF, an expanding in LNG supply will provide in preserving the reasonable LNG prices and this edges the domestic manufacturing industries [16]. US LNG exports also provide a reliable and alternative energy supply to the world marketplace, offering international buyers with a better alternative or an option, serving to limit the utilization of energy as a political weapon. Environmentally, US energy-related carbon dioxide emissions in 2015 were 12% below 2005 levels due to high utilization of natural gas by power generators. In addition, exporting LNG can decrease the global greenhouse gas emissions (GHG) [17]. ICF predicts that exported LNG can have GHG emissions in between of 43% to 52% which is much lower than the emissions of traditional oils. Moreover, Energy Department concludes that US’s natural gas used in Asia or Europe has lower life cycle of GHG emissions compared to the power generates by regional coal [14] (Figure 5).

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Iris Publishers-Open access Journal of Textile Science & Fashion Technology | Textile Science Behind the Mask Homemade with Love Filtered Cloth Mask

Authored by Sally M Di Marco*

Abstract

In order to address the needs of the current Covid-19 Pandemic for a safe face mask that can be worn for everyday wear, published scientific research was culled and utilized in the design and materials for creating the Homemade with Love (HWL) filtered cloth mask [1] (Figure 1). Researchers from the Argonne National Laboratory at the University of Chicago in the United States reported that high thread counts 100 percent plain woven cotton or cotton blends, along with a combination of layering of different fabrics, with electrostatic-based filtration produces a mask that can block “a vast majority of aerosol particles.” The HWL facemask meets the researcher’s findings, and it is compliant with the Center for Disease Control (CDC) guidelines for homemade masks [2].

Anatomy of the Mask

Style and fit

Mirrored after the surgical mask, the pleated design of the HWL mask contributes to the fit, skin comfort, and most importantly allows for adequate amount of airflow. According to the CDC article (2020) entitled, Considerations for Wearing Masks, “wearing a mask does not raise the carbon dioxide (CO2) level in the air you breathe. A cloth mask does not provide an airtight fit across the face. The CO2 completely escapes into the air through and around the sides of the cloth mask when you breathe out or talk. CO2 is small enough to easily pass through any cloth mask material. In contrast, the virus that causes COVID-19 is much larger than CO2, so it cannot pass as easily through a properly designed and properly worn cloth mask.” Additionally, the style of the mask minimizes the build-up of condensation, which can be a source of bacterial growth. The mask molds across the face, is gentle to the skin, and protective. Because it utilizes three layers of fabrics, it can be considered as a form of quilting, creating more padding in the construction process, and protection when worn (Figure 2).

Cutting the mask on the crosswise grain of the fabric, where the give of the fabric is predominant, allows for the mask to slightly stretch and accommodate the contours of the face. The crosswise or weft yarns run perpendicular to the selvage of the fabric. The selvage is the finished edge, on both sides of the fabric, which runs lengthwise and serves to finish off the edges. Adding purchased adjustable earpieces and a nose bridge further contributes to a well-fitting mask that will not slip and covers both the nose and the mouth.

Textile Science Behind the Mask

Public face of the mask

The HWL filtered mask is made exclusively out of quilter’s cotton for the fashion fabric (public side of the mask) and the lining (private side of the mask). Quilters 100 percent cotton is a plain, tightly woven, medium weight textile. It is crisper than standard cotton, absorbent, dries quickly, and holds up in the laundering process. The fabric is available in solid colors or printed after it is woven in a variety of patterns. Due to the nature of the fabric, it will withstand numerous washing cycles in cold and hot temperatures (Figure 3).

The HWL filtered mask is made exclusively out of quilter’s cotton for the fashion fabric (public side of the mask) and the lining (private side of the mask). Quilters 100 percent cotton is a plain, tightly woven, medium weight textile. It is crisper than standard cotton, absorbent, dries quickly, and holds up in the laundering process. The fabric is available in solid colors or printed after it is woven in a variety of patterns. Due to the nature of the fabric, it will withstand numerous washing cycles in cold and hot temperatures (Figure 3).

“quilter’s cotton” with a thread count of 180 or more, and those with especially tight weave and thicker thread such as batiks. A double-layer mask with a simple cotton outer layer and an inner layer of flannel also performed well, Dr. Segal said.” The testing was conducted at the Manufacturing Development Center at the Wake Forest Institute for Regenerative Medicine [3].

Private face of the mask: Lining

The HWL filtered mask is lined with 100 percent quilter’s cotton or a high-grade muslin in white, cream, or black. It is not advisable to line the mask in the fashion fabric if it is printed. To have a heavily dyed print fabric next to the face, especially near the mouth and nose is problematic and may cause allergic reactions in susceptible individuals (Figure 4).

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