Three-point iterative algorithm in the absence of the derivative for solving nonlinear equations and their basins of attraction

In this paper, we suggested and analyzed a new higher-order iterative algorithm for solving nonlinear equation $$g(x)=0$$ g ( x ) = 0 , $$g:{\mathbb {R}}\longrightarrow {\mathbb {R}}$$ g : R ⟶ R , which is free from derivative by using the approximate version of the first derivative, and we studied the basins of attraction for the proposed iterative algorithm to find complex roots of complex functions $$g:{\mathbb {C}}\longrightarrow {\mathbb {C}}$$ g : C ⟶ C . To show the effectiveness of the proposed algorithm for the real and the complex domains, the numerical results for the considered examples are given and graphically clarified. The basins of attraction of the existing methods and our algorithm are offered and compared to clarify their performance. The proposed algorithm satisfied the condition such that $$|x_{m}-\alpha |<1.0 \times 10^{-15}$$ | x m - α | < 1.0 × 10 - 15 , as well as the maximum number of iterations is less than or equal to 3, so the proposed algorithm can be applied to efficiently solve numerous type non-linear equations.

Comparative analysis on different software piracy prevention techniques

Numerous type of software piracy known today, have several prevention techniques which has been established against them. Although, different software piracy techniques have been established, but the choice of which one should be the best to develop any software is the challenge for most software developers. Consequently, example of the types of piracy in software development can be categorise as follows: cracks and serials, softlifting and hard disk loading, internet piracy and software forging, mischaneling, reverse engineering, and tampering. We have several types of prevention techniques which aimed to resolved piracy in software development, although the methods have been wrecked. In this work a critical analysis has been carryout on different software piracy techniques and a simple model software was designed using the best technique to validate the results of the analysis.

Short Communication: The bioinformatics perspective of Foeniculum vulgare fruit's bioactive compounds as natural anti-hyperglycemic against alpha-glucosidase

Rohman F, Putra WE. 2021. Short Communication: The bioinformatics perspective of Foeniculum vulgare fruit's bioactive compounds as natural anti-hyperglycemic against alpha-glucosidase. Biodiversitas 22: 79-84. The management in controlling the blood glucose level is crucially necessary to be promoted. Many reports showed the harmful effect of glucose toxicity, most of them are the cluster of metabolic disorder. Nowadays, natural products are getting much attention on health issues. The uses of medicinal plants for drug materials are dramatically increasing. In our previous study about local medicinal plants identification, we found that Tengger Tribe in Indonesia uses numerous type of species, including Foeniculum vulgare which was widely found and occupied as traditional medicine by Tengger Tribe in the area of Taman Nasional Bromo Tengger Semeru, East Java, Indonesia. According to their local belief, F. vulgare has been used to ameliorate several types of diseases. Thus, in this present study, we aimed to virtually evaluate the bioactive compounds of F. vulgare for anti-hyperglycemic against the alpha-glucosidase. We performed computational prediction of ligands-protein interaction by molecular docking approaches. The 2D structure of ligands and 3D structure of target protein were retrieved via the database. The natural compound's structure was then evaluated by the Lipinski rule of five to indicate whether it can be categorized as drug-like or not. Moreover, according to our simulation, F. vulgare fruit's bioactive compounds including sterol, anethole, and fenchone might have therapeutic effect to reduce the hyperglycemia incidence by inhibiting the alpha-glucosidase activity. Compared to miglitol, an alpha-glucosidase inhibitor, Sterol have the most significant binding affinity against the alpha-glucosidase. Therefore, these findings suggest that sterol, anethole, and fenchone might be potential new candidates for alpha-glucosidase inhibitors.

γ-Secretase Modulatory Proteins: The Guiding Hand Behind the Running Scissors

Described as the “proteasome of the membrane” or the “scissors in the membrane,” γ-secretase has notoriously complicated biology, and even after decades of research, the full extent of its regulatory mechanism remains unclear. γ-Secretase is an intramembrane aspartyl protease complex composed of four obligatory subunits: Nicastrin (NCT), Presenilin (PS), Presenilin Enhancer-2 (Pen-2), and Anterior pharynx-defective-1 (Aph-1). γ-Secretase cleaves numerous type 1 transmembrane substrates, with no apparent homology, and plays major roles in broad biological pathways such as development, neurogenesis, and cancer. Notch and the amyloid precursor protein (APP) and are undoubtedly the best-studied γ-secretase substrates because of their role in cancer and Alzheimer’s disease (AD) and therefore became the focus of increasing studies as an attractive therapeutic target. The regulation of γ-secretase is intricate and involves the function of multiple cellular entities. Recently, γ-secretase modulatory proteins (GSMPs), which are non-essential subunits and yet modulate γ-secretase activity and specificity, have emerged as an important component in guiding γ-secretase. GSMPs are responsive to cellular and environmental changes and therefore, provide another layer of regulation of γ-secretase. This type of enzymatic regulation allows for a rapid and fine-tuning of γ-secretase activity when appropriate signals appear enabling a temporal level of regulation. In this review article, we discuss the latest developments on GSMPs and implications on the development of effective therapeutics for γ-secretase-associated diseases such as AD and cancer.

Antimicrobial and Transconjugants Characteristics of Sul3 Positive Escherichia Coli Isolated from Animals in Nanning, Guangxi Province

Background: Sulfonamides is the second most popular antibiotic in many countries, which leads to the widespread emergence of sulfonamides resistance. Sul3 is a late sulfanilamide resistance gene, whose research is relatively little. Result: 46 sul3 positive E. coli strains were separated. A total of 12 ST types were observed, and 1 of those was previously unknown type. The ST350 is the most numerous type. All isolates were multidrug-resistant E. coli, with high antimicrobial rates to penicillin, ceftriaxone sodium, streptomycin, tetracycline, ciprofloxacin, gatifloxacin and chloramphenicol (100%, 73.9%, 82.6%, 100%, 80.4%, 71.7% and 97.8%), and with at least 3 resistance genes in addition to sul3. The plasmids transfered from 3 sul3-positive isolates to C600, the most of which brought 7 antibiotic resistance and increased resistance genes to C600. The transferred sul3 gene and the plasmid that carries it could be stably inherited in the recipient bacteria for at least 20 days. Those plasmids had no effect on the growth of the recipient bacteria, but it would greatly reduce (at least 60 time) the in vitro competitiveness of the strains. Conclusions: In Nanning, these sul3-positive Escherichia coli have strong antimicrobial resistance, and the plasmid carrying sul3 has the ability to transfer multiple resistance genes, so long-term monitoring is necessary. Since the transferred plasmid will greatly reduce the in vitro competitiveness of the strain, we can consider limiting the spread of antimicrobial in this respect.

PE5–PPE4–EspG3 heterotrimer structure from mycobacterial ESX-3 secretion system gives insight into cognate substrate recognition by ESX systems

Mycobacterium tuberculosis has evolved numerous type VII secretion (ESX) systems to secrete multiple factors important for both growth and virulence across their cell envelope. ESX-1, ESX-3, and ESX-5 systems have been shown to each secrete a distinct set of substrates, including PE and PPE families of proteins, named for conserved Pro-Glu and Pro-Pro-Glu motifs in their N termini. Proper secretion of the PE–PPE proteins requires the presence of EspG, with each system encoding its own unique copy. There is no cross-talk between any of the ESX systems, and how each EspG recognizes its subset of PE–PPE proteins is currently unknown. The only current structural characterization of PE–PPE–EspG heterotrimers is from the ESX-5 system. Here we present the crystal structure of the PE5mt–PPE4mt–EspG3mm heterotrimer from the ESX-3 system. Our heterotrimer reveals that EspG3mm interacts exclusively with PPE4mt in a similar manner to EspG5, shielding the hydrophobic tip of PPE4mt from solvent. The C-terminal helical domain of EspG3mm is dynamic, alternating between “open” and “closed” forms, and this movement is likely functionally relevant in the unloading of PE–PPE heterodimers at the secretion machinery. In contrast to the previously solved ESX-5 heterotrimers, the PE–PPE heterodimer of our ESX-3 heterotrimer is interacting with its chaperone at a drastically different angle and presents different faces of the PPE protein to the chaperone. We conclude that the PPE–EspG interface from each ESX system has a unique shape complementarity that allows each EspG to discriminate among noncognate PE–PPE pairs.

PE5-PPE4-EspG3 trimer structure from mycobacterial ESX-3 secretion system gives insight into cognate substrate recognition by ESX systems

ABSTRACTMycobacterium tuberculosis (Mtb) has evolved numerous type VII secretion (ESX) systems to secrete multiple factors important for both growth and virulence across their cell envelope. Three such systems; ESX-1, ESX-3, and ESX-5; have been shown to each secrete a unique set of substrates. A large class of these substrates secreted by these three systems are the PE and PPE families of proteins. Proper secretion of the PE-PPE proteins requires the presence of EspG, with each system encoding its own unique copy. There is no cross-talk between any of the ESX systems and how each EspG is recognizing its subset of PE-PPE proteins is currently unknown. The only current structural characterization of PE-PPE-EspG trimers is from the ESX-5 system. Here we present the crystal structure of the PE5mt-PPE4mt-EspG3mm trimer, from the ESX-3 system. Our trimer reveals that EspG3mm interacts exclusively with PPE4mt in a similar manner to EspG5, shielding the hydrophobic tip of PPE4mt from solvent. The C-terminal helical domain of EspG3mm is dynamic, alternating between an ‘open’ and ‘closed’ form, and this movement is likely functionally relevant in the unloading of PE-PPE heterodimers at the secretion machinery. In contrast to the previously solved ESX-5 trimers, the PE-PPE heterodimer of our ESX-3 trimer is interacting with it’s chaperone at a drastically different angle, and presents different faces of the PPE protein to the chaperone. We conclude that the PPE-EspG interface from each ESX system has a unique shape complementarity that allows each EspG to discriminate amongst non-cognate PE-PPE pairs.

An "achtformige" bronze lamp from Ptuj/Poetovio

This research highlights an open-shape copper-alloy lamp to be used with tallow (type Loeschcke XXV), recently discovered at Poetovio, among a huge number of standard imported Roman oil lamps. This form, together with its clay counterpart (type Loeschcke XI), are typical of the northern Roman limes provinces, where they were produced and used almost exclusively. Finding such a lamp so far south merits note, hence the discussion of the distribution of known parallels, made of different metals, as well as a brief consideration of a very eclectic clay variant, which is marginal almost everywhere except at Trier, where it constitutes by far the most numerous type of Roman lamps found in situ.

Verrucous antral gastritis in relation to Helicobacter pylori infection, nutrition, and gastric atrophy

Background There have been few studies in the English literature regarding verrucous gastritis (VG). The present study investigated the clinical and endoscopic features of verrucous antral gastritis, especially focusing on Helicobacter pylori infection, nutrition, and gastric atrophy. Methods We performed a retrospective study of patients who underwent routine endoscopy with indigo carmine chromoendoscopy and a comparative study was conducted between VG-positive and VG-negative groups. VG was subdivided into classical and numerous types based on the number and distribution of verrucous lesions. Demographic, clinical, and endoscopic data including body mass index (BMI), serum albumin and cholesterol, gastric atrophy, reflux oesophagitis, Barrett’s oesophagus, and H. pylori status were collected. Univariate and multivariable analyses were performed to identify factors associated with VG. Results We analysed the data of 621 patients undergoing routine endoscopy and found that VG (n = 352) was significantly associated with increased BMI (1.12 [1.05–1.18], P &lt; 0.01), reflux esophagitis (1.96 [1.10–3.28], P &lt; 0.01), and H. pylori negativity with or without a history of eradication (9.94 [6.00–16.47] and 6.12 [3.51–10.68], P &lt; 0.001, respectively). Numerous-type (n = 163) VG was associated with both closed- and open-type gastric atrophy (9.9 [4.04–21.37] and 8.10 [3.41–19.24], P &lt; 0.001, respectively). There were no statistical differences between groups regarding age, sex, total cholesterol, albumin, and bile-colored gastric juice. Conclusions Verrucous antral gastritis was related to increased BMI, reflux esophagitis, and H. pylori negativity. Numerous-type verrucous lesions were associated with gastric atrophy. These indicate that VG may be a physiological phenomenon due to high gastric acidity, mechanical overload, and vulnerability of background mucosa.