Sigma Partitioning: Complexity and Random Graphs

A $\textit{sigma partitioning}$ of a graph $G$ is a partition of the vertices into sets $P_1, \ldots, P_k$ such that for every two adjacent vertices $u$ and $v$ there is an index $i$ such that $u$ and $v$ have different numbers of neighbors in $P_i$. The $\textit{ sigma number}$ of a graph $G$, denoted by $\sigma(G)$, is the minimum number $k$ such that $G$ has a sigma partitioning $P_1, \ldots, P_k$. Also, a $\textit{ lucky labeling}$ of a graph $G$ is a function $\ell :V(G) \rightarrow \mathbb{N}$, such that for every two adjacent vertices $v$ and $u$ of $G$, $\sum_{w \sim v}\ell(w)\neq \sum_{w \sim u}\ell(w)$ ($x \sim y$ means that $x$ and $y$ are adjacent). The $\textit{ lucky number}$ of $G$, denoted by $\eta(G)$, is the minimum number $k$ such that $G$ has a lucky labeling $\ell :V(G) \rightarrow \mathbb{N}_k$. It was conjectured in [Inform. Process. Lett., 112(4):109--112, 2012] that it is $\mathbf{NP}$-complete to decide whether $\eta(G)=2$ for a given 3-regular graph $G$. In this work, we prove this conjecture. Among other results, we give an upper bound of five for the sigma number of a uniformly random graph

Bioinformatics analysis of analgesic-antitumor like peptide from Iranian scorpion Mesobuthus eupeus

زمینه و هدف: در سال های اخیر مطالعات متعددی بر روی سموم حیوانات و حشرات برای یافتن مولکول هایی با خواص دارویی انجام شده است. سموم عقرب دارای مولکول های کوچکی با خواص زیستی و دارویی مختلف می باشند. یکی از این توکسین ها پپتید آنتی تومور- ضددرد (AGAP) است که در درمان سرطان و تسکین درد موثر می باشد. در این مطالعه تحقیقی به تعیین توالی و بررسی های بیوانفورماتیکی ژن کدکننده ی پپتید شبه AGAP از عقرب زرد ایرانی پرداخته شد. روش بررسی: در این مطالعه تجربی، نمونه های عقرب زرد ایرانی Mesobuthus eupeus جمع آوری و پس از استخراج DNA با پرایمرهای اختصاصی نواحی حفاظت شده، تکثیر ژن کدکننده ی پپتید سمی مشابه AGAP انجام شد و(MeI AGAP) Mesobuthus eupeus Iranian AGAP نام گرفت. سپس توالی ژن شبه AGAP جهت بررسی های قرابتی با کمک نرم افزار CLC main workbench 5 با توالی های سموم مشابه از گونه های دیگر عقرب مقایسه شد؛ همچنین توالی اینترون، عناصر تنظیمی، جایگاه های پیرایش و موقعیت آدنین نقطه ی شاخه ساز این توکسین با توالی های مشابه مورد بررسی قرار گرفت. یافته ها: توالی ژنی MeI AGAP درحدود 507 نوکلئوتید دارد. توالی ژنی این توکسین کوتاه تر از توالی ژنی توکسین BmK AGAP به دست آمده از عقرب Buthus martensii می باشد که علت آن حذف بزرگی در توالی اینترونی آن است. توالی کدکننده ی پپتید بالغ در این توکسین تشابه 93 با توکسین BmK AGAP دارد. مطالعه ی توالی ژنی توکسین MeI AGAP از عقرب ایرانی مزوبوتوس اوپئوس تاکنون انجام نشده و گزارش توالی آن برای نخستین بار، در این مطالعه صورت گرفت. نتیجه گیری: بررسی همولوژی این توکسین با توکسین های دیگر از عقرب های مختلف، تفاوت های متعددی نشان داد که می تواند خاص گونه ی ایرانی باشد؛ همچنین تشابه زیاد با توکسین BmK AGAP، MeI AGAP را به­عنوان دارویی برای درمان سرطان و تسکین درد مطرح می کند

Identification of Appropriate Probe Site in Maxillary Anterior Teeth for Electric Pulp Testing

Objectives This study aimed to find the appropriate probe site for electric pulp testing (EPT) in maxillary anterior teeth. Methods Forty patients with available panoramic radiographs referred to the Endodontics Department were studied. In each patient, three intact teeth, including central incisor, lateral incisor, and canine, were selected from one quadrant of the maxillary arch. The incisal third, middle third, and cervical third of the buccal surface of the teeth were assessed. The respective teeth were isolated with rubber dam without a clamp. EPT was conducted starting with the lowest intensity, which gradually increased until the patient reported a sense of tingling, stinging, or heat. This process was repeated for all respective teeth at the three areas. Data were analyzed by the Friedman test (P<0.05), ANOVA (P<0.001), and Man-Whitney test (P>0.05). Results The middle third of all three maxillary anterior teeth was an appropriate site for EPT. The lateral incisor had the lowest threshold response in all three areas compared with other teeth. No significant difference was observed between male and female patients (P>0.05). Conclusion Within the limitations of this study, it may be concluded that the middle third of the buccal surface of maxillary anterior teeth is an optimal electrode placement site

The response of pre-inflammatory cytokines factors to different exercises (endurance, resistance, concurrent) in overweight men

Applying several energy systems and concurrent performing of various training models have a more effective role in preventing precocious occurrence of many diseases compared to training single energy system. This can be seen in case of physiologic and metabolic adaptations of the human body too. The present study attempted to investigate the effect of endurance, resistance and concurrent (endurance–resistance) training on pre-inflammatory cytokines in overweight men. Accordingly, 43 healthy overweight (BMI = 28.56± 2.67) young (23.7± 3.3 yr) students were volunteered to participate and randomly divided into three experimental (n= 11) and one control (n= 10) groups. The experimental groups performed 3 days/wk endurance, resistance and concurrent training for 8 weeks. Also, prior to and after the training, a blood sample was collected from the subjects in order to measure pre-inflammatory cytokines (IL-1b, IL-6 and TNF-a). Following 8 week training, repeated measure ANOVA results showed a significant difference in IL-1b (P =0.046) and IL-6 (P = 0.009) compared to baseline. However, this was not the case with the TNF-a. Furthermore, between group comparisons showed significant difference in IL-6 (P =0.020) between endurance and resistance groups. Within group comparisons (depended t student test) also showed a significant difference in IL-1b and IL-6 of endurance and concurrent groups compared to baseline. Generally, it can be concluded that endurance and concurrent exercise training in part has a positive effect on pre-inflammatory cytokines

Novel Layered Double Hydroxides-Hydroxyapatite/gelatin Bone Tissue Engineering Scaffolds: Fabrication, Characterization, and in Vivo Study

Developing Porous Biodegradable Scaffolds through Simple Methods is One of the Main Approaches of Bone Tissue Engineering (BTE). in This Work, a Novel BTE Composite Containing Layered Double Hydroxides (LDH), Hydroxyapatite (HA) and Gelatin (GEL) Was Fabricated using Co-Precipitation and Solvent-Casting Methods. Physiochemical Characterizations Showed that the Chemical Composition and Microstructure of the Scaffolds Were Similar to the Natural Spongy Bone. Interconnected Macropores Ranging over 100 to 600 Μm Were Observed for Both Scaffolds While the Porosity of 90 ± 0.12% and 92.11 ± 0.15%, as Well As, Young\u27s Modulus of 19.8 ± 0.41 and 12.5 ± 0.35 GPa Were Reported for LDH/GEL and LDH-HA/GEL Scaffolds, Respectively. the Scaffolds Were Degraded in Deionized Water after a Month. the SEM Images Revealed that between Two Scaffolds, the LDH-HA/GEL with Needle-Like Secondary HA Crystals Showed Better Bioactivity. According to the Alkaline Phosphatase Activity and Alizarin Red Staining Results, LDH-HA/GEL Scaffolds Demonstrated Better Bone-Specific Activities Comparing to LDH/Gel Scaffold as Well as Control Sample (P \u3c 0.05). the Rabbit Adipose Stem Cells (ASCs) Were Extracted and Cultured, Then Seeded on the LDH-HA/GEL Scaffolds after Confluence. Three Groups of Six Adult Rabbits Were Prepared: The Scaffold + ASCs Group, the Empty Scaffold Group and the Control Group. the Critical Defects Were Made on the Left Radius and the Scaffolds with or Without ASCs Were Implanted There While the Control Group Was Left Without Any Treatment. All Animals Were Sacrificed after 12 Weeks. Histomorphometric Results Showed that the Regeneration of Defects Was Accelerated by Scaffold Implantation But ASC-Seeding Significantly Improved the Quality of New Bone Formation (P \u3c 0.05). the Results Confirmed the Good Performance of LDH-HA/GEL Scaffold to Induce Bone Regeneration

Comparison of zeta potential and physiological intracytoplasmic sperm injection in obtaining sperms with a lower DNA fragmentation index: A cross-sectional study

Background: The sperm DNA fragmentation index (DFI) is one of the men’s reproductive health criteria that affects assisted reproductive technique outcomes. Efforts in obtaining high-quality mature sperms seem to be necessary. Advanced sperm selection techniques (including physiological intracytoplasmic sperm injection [PICSI], zeta potential, microfluidic, etc.) have gained popularity in this regard. Objective: The study aimed to compare the efficacy of zeta potential and PICSI sperm selection in obtaining sperms with better DNA integrity. Materials and Methods: In this cross-sectional study, 48 couples were enrolled where the male partner had increased sperm DFI in his ejaculated sample and the female was in normal reproductive health. For each male partner, the semen sample was processed with zeta potential and PICSI techniques, then the sperm DFI of neat semen was compared to zeta and PICSI samples by the sperm chromatin dispersion test. Results: Data showed that both the zeta potential and PICSI technique decreased sperm DFI in comparison with the neat semen sample (p < 0.001 for both). In addition, there was a statistically significant difference in sperm DFI between the PICSI and zeta potential samples (p < 0.01). Conclusion: The current study showed that both zeta potential and PICSI could result in sperm with a lower DFI. However, PICSI seems to be superior to zeta potential in this regard. Key words: PICSI, ZETA potential, Hyaluronic acid, DNA integrity