*2.1. Ethics Statement*

All subjects gave their informed consent for inclusion before they participated in this study. This study was approved by the Ethics Committee of the Instituto Nacional de Perinatologia (INPer) Isidro Espinosa de los Reyes in Mexico City (Register<PHONE_NUMBER>-10107-01-16) and San Judas Tadeo Hospital in Mexico City.


**Embryo Implantation and Placental Development**

Editor

**Luisa Campagnolo**

MDPI ' Basel ' Beijing ' Wuhan ' Barcelona ' Belgrade ' Manchester ' Tokyo ' Cluj ' Tianjin

*Editor* Luisa Campagnolo Biomedicine and Prevention Tor Vergata Rome Italy

*Editorial Office* MDPI St. Alban-Anlage 66 4052 Basel, Switzerland

This is a reprint of articles from the Special Issue published online in the open access journal *International Journal of Molecular Sciences* (ISSN 1422-0067) (available at: www.mdpi.com/journal/ ijms/special issues/Embryo Implantation).

For citation purposes, cite each article independently as indicated on the article page online and as indicated below:

LastName, A.A.; LastName, B.B.; LastName, C.C. Article Title. *Journal Name* **Year**, *Volume Number*, Page Range.

**ISBN 978-3-0365-5854-7 (Hbk) ISBN 978-3-0365-5853-0 (PDF)**

© 2022 by the authors. Articles in this book are Open Access and distributed under the Creative Commons Attribution (CC BY) license, which allows users to download, copy and build upon published articles, as long as the author and publisher are properly credited, which ensures maximum dissemination and a wider impact of our publications.

The book as a whole is distributed by MDPI under the terms and conditions of the Creative Commons license CC BY-NC-ND.


**1. Introduction**

A pandemic presents a special kind of health crisis that requires "collective responsibility" together with changes in communication techniques ([1], p. 515). Previous research has confirmed that communication during a health crisis is crucial [2] in order to create awareness for the existence of a health threat [3, 4]. Hence, health risk messages disseminated during the crisis should be both instructing and adjusting, informing the public of which precautionary measures to take to reduce physical harm and the virus from spreading, while also providing individuals with guidance as to how to deal with the psychological threats of the crisis [5].

In the event of a pandemic, the government becomes a key actor in managing the (health) crisis [6, 7]. Conditioned by high degrees of trust, messages distributed on part of the government can drive the general population to comply with its recommended actions [8–11]. This is the case, since health messages for which the government is the identified source are perceived as both credible and relevant [7, 12], for individuals are convinced that the government can control the crisis [13]. This is

in line with previous research, which suggests that controllability and responsibility for the health threat influence the public's risk perceptions and, consequently, responses to these risks [14].

The primary aim of this chapter is to present some guidelines for effective health risk message design, drawing input from established crisis communication literature in general and some recent studies on COVID-19 risk communication in particular. To this end, recommendations regarding message presentation and design will be presented, before limitations and directions for future research are addressed.


*Article* **Influence of Axial Depth of Cut and Tool Position on Surface Quality and Chatter Appearance in Locally Supported Thin Floor Milling**

**Mikel Casuso 1,\*, Antonio Rubio-Mateos 1, Fernando Veiga 1 and Aitzol Lamikiz 2**

**Abstract:** Thin floor machining is a challenging and demanding issue, due to vibrations that create poor surface quality. Several technologies have been developed to overcome this problem. Ad hoc fixtures for a given part geometry lead to meeting quality tolerances, but since they lack flexibility, they are expensive and not suitable for low manufacturing batches. On the contrary, flexible fixtures consisting of vacuum cups adaptable to a diversity of part geometries may not totally avoid vibrations, which greatly limits its use. The present study analyses the feasibility of thin floor milling in terms of vibration and roughness, in the cases where milling is conducted without back support, a usual situation when flexible fixtures are employed, so as to define the conditions for a stable milling in them and thus avoid the use of ad hoc fixtures. For that purpose, the change of modal parameters due to material removal and its influence on chatter appearance have been studied, by means of stability lobe diagrams and Fourier Transform analysis. Additionally, the relationship between surface roughness and chatter frequency, tooth passing frequency, and spindle frequency have been studied. Ploughing effect has also been observed during milling, and the factors that lead to the appearance of this undesirable effect have been analyzed, in order to avoid it. It has been proven that finish milling of thin floors without support in the axial direction of the mill can meet aeronautic tolerances and requirements, providing that proper cutting conditions and machining zones are selected.

**Keywords:** finish milling; chatter; part quality; AA2024 floor milling


**2. Precipitating factors in CAPS**

Infections

Postpartum or recent fetal loss

Minor surgical procedures or surgery

Other: malignancy, medication, anticoagulation withdrawal, and SLE exacerbation.

Although the pathogenesis of CAPS continues to be insufficiently understood, antiphospholipid (aPL) antibodies (Ab) belong to the immunoglobulin (Ig) family and are directed against phospholipid-binding plasma proteins such as Beta2 Glycoprotein1 (B2- GP1), prothrombin, annexin V, PS, PC, etc.

As a consequence of initial damage, anionic phospholipids would be exposed on the cell surface B2-GP1. If there are circulating anti-B2-GP1 Ab, they will bind to this complex, inducing cell activation with the release of tissue factor (TF), adhesion molecules, IL-8, C3b, C5a, among others, such as the activation of leukocytes and platelets. This increases their adhesion to the vascular endothelium, promoting microthrombosis and promoting the release of proteases and free radicals. Multiple vascular occlusion triggers necrosis tissue with excessive release of cytokines. A present marker is ferritin, which is elevated in 71% of CAPS patients and according to a recent study could play a role in the pathogenesis of APS and as a follow-up marker in CAPS [6, 7].

Kitchen postulates that vascular occlusion triggers additional thrombosis ("thrombotic storm"), which leads to increased thrombin and decreased fibrinolysis. As her son proposes the theory of "molecular mimic-cry" (molecular imitation), where on one hand the anti-B2-GP1 Ab when bound to the B2-GP1 of *COVID-19 and Catastrophic Antiphospholipid Syndrome DOI: http://dx.doi.org/10.5772/intechopen.99896*

the endothelial cell generate a procoagulant state and on the other hand, certain viruses and bacteria that have an amino acid sequence similar to that of B2-GP1. This therefore favors the synthesis of more Ab. Furthermore, B2-GP1 could activate the immune response through interaction with a membrane receptor TLRs (tolllike) and from this a series of signals are generated, which increase the production of proinflammatory cytokines (TNF, IL-1B, IL-6, IL.8) and FT, PAI-1, PAF, etc. leading to multi-organ failure [8].


**1. Introduction**

Alginate is derived from the cell wall and intercellular substance of brown seaweed, accounting for approximately 22–44% (*w*/*w*) of seaweed biomass [1]. It is a kind of linear, water-soluble, and acidic polysaccharide composed of one or both of *β*-D-mannuronic acid (M) and its C-5 epimer *α*-L-guluronic acid (G) [2]. The M and G subunits form polyguluronic acid (poly-*α*-L-guluronate, polyG), polymannuronic acid (poly-*β*-D-mannuronate, polyM), and mixed random polymer (polyGM) in three types of block structures by α/β-1,4 glycosidic bonds [3]. Alginate is widely used in the field of food and pharmaceutical industry owing to its high viscosity and gelling properties. Further, it has attracted attention as a promising marine biomass for the production of biofuels and chemicals in biorefinery applications [4].

Alginate oligosaccharide (AOS) is an oligomer of alginate, which has the characteristics of low relative molecular weight, good solubility, high safety, and high stability. It is

**Citation:** Huang, H.; Li, S.; Bao, S.; Mo, K.; Sun, D.; Hu, Y. Expression and Characterization of a Cold-Adapted Alginate Lyase with Exo/Endo-Type Activity from a Novel Marine Bacterium *Alteromonas portus* HB161718T. *Mar. Drugs* **2021**, *19*, 155. https://doi.org/10.3390/ md19030155

Academic Editor: Irina M. Yermak

Received: 20 February 2021 Accepted: 12 March 2021 Published: 17 March 2021

**Publisher's Note:** MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

**Copyright:** © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

reported that AOS has potential applications in agricultural, health product, and medical industries, since it exhibits significant pharmacological, physiological, and biological activities, including antioxidant, immunomodulation, antibacterial, antitumor, anticoagulation, and plant growth-promoting activities [5–7].

Alginate lyase is adopted to catalytically degrade alginate into AOS by *β*-elimination under relatively mild and controllable conditions. According to the substrate specificity, alginate lyases can be classified into three groups: polyM-specific lyase (EC <IP_ADDRESS>), polyGspecific lyases (EC <IP_ADDRESS>), and polyMG-specific lyases (EC 4.2.2) that can degrade polyG, polyM, and polyMG blocks of alginate, respectively [8]. Alginate lyases can be classified into endo- and exo-lytic fashions, according to the mode of degradation of alginate. Endolytic enzymes can cleave the glycosidic bonds inside the alginate with unsaturated oligosaccharides as the main products, while exotype ones can degrade oligomeric alginates and alginate polymers into monomers [9,10]. Furthermore, on the basis of their amino acid sequence similarities, the enzymes are generally grouped into seven polysaccharide lyases (PL) families in the Carbohydrate-Active Enzymes (CAZy) database—that is, PL-5, -6, -7, -14, -15, -17, and -18 [11,12]. Alginate lyases from the PL7 family have been widely studied, e.g., NitAly from *Nitratiruptor* sp. SB155-2 [13], lyA from *Isoptericola halotolerans* NJ-05 [14], Aly1281 from *Pseudoalteromonas carrageenovora* ASY5 [15], and MtAl138 from *Microbulbifer thermotolerans* DAU221 [16]. Alginate lyases are widely derived from marine algae; mollusks; and microorganisms (including bacteria, fungi, and viruses), among which marine bacteria are the most common resources. Many kinds of alginate lyase-secreting bacteria have been reported from marine bacteria, such as *Pseudoalteromona*, *Alteromonas*, *Microbulbifer*, *Zobellia*, *Vibrio*, and *Bacillus* [9,17–19].

In our previous study, a novel alginate lyase-producing strain, *Alteromonas portus*, was obtained from marine sand sample and taxonomically studied [17]. In this work, a gene *alg2951*, encoding alginate lyase Alg2951, was studied for a cloning, expression, and degradation product analysis. The results showed that Alg2951 was a cold-adapted PL7 alginate lyase with significant preference toward polyG. Moreover, Alg2951 was shown to be a NaCl- and KCl-activated enzyme with exolytic and endolytic activity, which released 4- deoxy-L-erythro-5-hexoseulose uronic acid (DEH) and trisaccharide from sodium alginate. In addition, the antioxidant capacity of the obtained AOS was investigated.


**2. Search strategy and selection criteria**

A literature search was performed up to April 2016 using the MEDLINE database, PubMed and Google Scholar search services with the following key words and word combinations: dementia, Alzheimer's disease, ageing, vision, eye, physiopathology, visual pathway, visual psychophysical test, optical coherence tomography, glaucoma.

After filtering by author criteria, English or Spanish language, and the condition that they all addressed dementia and vision as the main theme, 325 articles were included after a full text review. All the abstracts were then carefully divided into subcategories covering topics including ageing and vision, visual pathway, physiopathology, visual psychophysical test, Alzheimer's and glaucoma.

This review covers systematic reviews, original articles and letters to the editor. We did not contact other authors for further articles inclusion.


*Endothelial Dysfunction in Appendicitis DOI: http://dx.doi.org/10.5772/intechopen.107480*

**Figure 1.** *The anatomy of vermiform appendix and the cecum (left) and its anatomical variations (right) [6].*

appendicular artery was 1 single branch from the ileocolic artery vascularize the whole appendix which then performed networks of smaller arteries perforating into the layers of appendix. The vascularization of the appendix originates from mesenteric blood circulation which is also responsible for other parts of the intestinal circulation. The appendicular artery is one of the most distal parts of the branches from the superior mesenteric circulation. Although it is part of the huge mesenteric circulation, as appendiceal circulation took a little part and branch among the circulation, the regulation of blood flow is less and lower than in other parts of the mesenteric circulation such as in the ileum or ascending colon. However, regulation of the blood flow is commonly maintained by local factors with vasodilator effects induced and attributed by hypoxia or cytokines of inflammation to cause an increase in blood flow to the appendix. Certain osmotic mechanisms, autonomic and neurohumoral, also the intestinal wall activity of peristalsis affect the blood flow in the mesenteric circulation primarily the special circulation to the appendix [6, 8].

Metabolic end products from the tissue in the vermiform appendix were drained away by the venous drainage which anatomically will join the venous blood flow in the ileocolic vein and the superior mesenteric vein. Another non-venous drainage of the appendix occurs by the lymphatic drainage of the cecum and the appendix which passes the lymph nodes in the mesoappendix and ileocolic lymph nodes surrounding the ileocolic artery into a group of superior mesenteric lymph nodes (**Figure 2**) [9].

The vermiform appendix is known as a vestigial organ embryologically and by the evolution of mammals. The main functions of vermiform appendicitis itself remain unknown. Theories stated that in humans the vermiform appendix no longer functions but other theories counters. As histologically it is rich in lymphoid tissue and its vascularization and lymphatics, its function is mostly discussed related to the immunological functions, especially to the gastrointestinal system. As its luminal and noncontinuous structure, the vermiform appendix was also hypothesized to be a reservoir for gut microbiota. This function and structure were suspected to have strong correlations to inflammatory mediators and microbiological mechanisms of the bacteria.

**Figure 2.** *Arterial supply of the vermiform appendix [6].*

This puts the vermiform appendix as an organ with a lot of risks of inflammations and infections its homeostasis was disrupted [10].


**3D Innovations in Personalized Surgery**

Editors

**Joep Kraeima Sebastiaan de Visscher Max Witjes**

MDPI Basel Beijing Wuhan Barcelona Belgrade Manchester Tokyo Cluj Tianjin

*Editors* Joep Kraeima 3D LAB and OMFS Groningen Groningen Netherlands

Sebastiaan de Visscher OMFS Groningen Groningen Netherlands

Max Witjes 3D Lab and OMFS Groningen Groningen Netherlands

*Editorial Office* MDPI St. Alban-Anlage 66 4052 Basel, Switzerland

This is a reprint of articles from the Special Issue published online in the open access journal *Journal of Personalized Medicine* (ISSN 2075-4426) (available at: www.mdpi.com/journal/jpm/ special issues/3D Personalized Surgery).

For citation purposes, cite each article independently as indicated on the article page online and as indicated below:

LastName, A.A.; LastName, B.B.; LastName, C.C. Article Title. *Journal Name* **Year**, *Volume Number*, Page Range.

**ISBN 978-3-0365-6484-5 (Hbk) ISBN 978-3-0365-6483-8 (PDF)**

© 2023 by the authors. Articles in this book are Open Access and distributed under the Creative Commons Attribution (CC BY) license, which allows users to download, copy and build upon published articles, as long as the author and publisher are properly credited, which ensures maximum dissemination and a wider impact of our publications.

The book as a whole is distributed by MDPI under the terms and conditions of the Creative Commons license CC BY-NC-ND.