This paper consists of two folds. At first, we deal with the stability analysis of a linear system of delay differential equations. It is shown that the direct and cluster treatment methods are not applicable if there are some purely imaginary roots of the characteristic equation with multiplicity greater than one. To overcome the above difficulty, the system is decomposed into several subsystems. For the decomposition of a system, an invertible transformation is required to convert the matrices of the system into a block triangular (diagonal) form Simultaneously. To achieve this goal, a necessary and sufficient condition is established. The second part concerns the stabilization of a linear system of delay differential equations using the delayed feedback method and design a controller for generating the desired response. More precisely, the unstable poles of the linear system of delay differential equations are moved to the left-half of the complex plane by the delayed feedback method. It is shown that the performance of the linear system of delay differential equations can be improved by applying the delayed feedback method.

Let V be a finite-dimensional right vector space over a division ring D and let C be a collection of linear transformations on V. In case of vector spaces over fields some authors have derived conditions on C which imply its triangularizability. Here, we will generalize some of these results to the case of vector spaces over division rings. We let C be a left artinian ring of linear transformations and prove a block triangularization theorem for C. The theorem is then used to extend two well-known results in the theory of triangularization.  

Determination of the ultimate pit limit is one of the most important design in open pit mining. In the present methods, the final pit is determined based on the maximization of undiscounted profit. For this purpose, various mathematical, heuristic and meta-heuristic algorithms have been developed. Among these methods the most used one is the Lerchs-Grossman (LG) algorithm. It has been mentioned that it is better to design the ultimate pit based on the maximization of the net present value. In other words, the optimal arrangement of blocks and the final pit outline must be determined Simultaneously. For that reason, in this paper the binary and nonlinear mathematical model of this problem and some suggestions for its linearization have been presented. In addition, in order to reduce the number of decision variables the concepts of the earliest and the latest possible time for extracting a block have been defined. In the following, with the use of downward cone and positional weight and the earliest extraction time of ore blocks, two heuristic algorithms have been developed for Simultaneous determination of the final pit and blocks extraction sequence. At the end the results of these algorithms have been compared with the LG algorithm. The results show that these algorithms are capable to produce good result.

Strength measurement of rock requires testing that must be carried out on test specimens with particular sizes in order to fulfill testing standards or suggested methods. Often, the coring process breaks up the weaker core pieces, and they are too small to be used in either index tests or conventional strength tests such as point load index (Is) and Brazilian tensile strength (BTS). One of the index tests to indirectly determine the rock strength is the block punch index (BPI) test, which requires flat disc specimens without special treatment. This study aimed to evaluate the applicability of the BPI test for predicting the uniaxial compressive strength (UCS), BTS and IS of the sandstones by empirical equations. Also, we have compared the performance of the BPI and IS for predicting the UCS and BTS. It was experimentally shown that BPI is a reliable method for predicting the UCS, BTS and Is of the sandstones under study. Moreover, the results indicate that BPI could be utilized with same importance as Is for predicting the UCS, while predicting the BTS by Is appears to be more reliable than BPI.

Introduction: After caesarean, mothers need to take care of their babies as soon as possible, and pain relief in them leads to more comfort and faster recovery and it reduces hospitalization time and complications such as pulmonary thromboembolism as well as treatment costs.Objective: Determining the effect of TAP block by injection of Bupivacaine 0.25% after caesarean section on post operative pain.Materials and Methods: This study was performed on seventy six women that underwent elective caesarean section. Then, the women were randomly divided into two groups. Six women were excluded from the study which was a double-blind clinical trial. In the case group: 20cc of Bupivacaine 0.25% was injected between transverse abdominal muscle fascia and internal oblique muscle fascia, and in control group the same amount of normal saline was used. Pain intensity was measured by VAS score at 2, 4, 6, 12, 24, 48 hours after surgery. In both groups, if the patient needed pain relief, diclofenac suppository was used and its dose was recorded. Some complications such as nausea, vomiting and dizziness were recorded too, data were analyzed by SPSS (21) software, P value less than 0.05 was considered statistically significant.Results: VAS score at 2, 4, 6 hours after surgery in case group was significantly lower than that in the control group. (P=0.0001, P=0.0001, P=0.039), respectively. The mean number of administered diclofenac in bupivacaine group was lower than that in placebo group (P=0.0001). The mean and standard deviation of pain free period in bupivacaine group was 13.77±2.41 and in placebo group was 5.94± 1.27. Survival rate of analgesia was 14.3% in bupivacaine group and 2.9% in placebo group. This difference was statistically significant (P= 0.001).Conclusion: Transverse abdominal plane block with Bupivacaine 0.25% can reduce post caesarean pain without any side effects, such as dizziness, nausea and vomiting, and any effect on the time of ambulation. It can also reduce use of analgesics.

Purpose: Together with the increase of orthodontic treatment needs the use of functional apparatus has been increased. Furthermore, different studies has been done on skeletal and dental changes after the use of these functional appliances, but few studies discussed soft tissue changes in the field. So, this study was carried out in order to evaluate soft tissue changes following the use of Twin block functional appliance.Methods & Materials: This study was quazi experimental done on 13 patients (7 girls and 6 boys) with 7 years and 7 months to 12 years and 6 months of age. All patients were Cl II Div.I malocclusion, Iranian, Muslim, resident of Tehran and with no previous orthodontic treatment and tooth extraction. The period of treatment with the apparatus varied between 7 to 17 months. The studied angular variables were nasolabial, nasofacial, facial convexity,H angle, mentocervical, nasomental and mentolabial. The liner variables were lower and upper lip to E line, upper and lower lip thickness, prominence and length, upper and lower face height. All variables were compared before and after the use of Twin block and recorded in a questionnaire and were analyzed by T - test. Results: The study showed that nasolabial, nasofacial, Lower lip to E line and Upper lip length decreased slightly with the use of apparatus, while facial convexity, H angle, upper lip prominence, upper lip thickness and upper lip to E line decreased significantly. As well as, mentocervical, upper lip thickness, lower lip prominence and soft tissue lower face height increased slightly and nasomental, mentolabial, soft tissue upper face height and lower lip length increased significantly.Conclusion: Following the treatment with Twin block, the lower face soft tissue moved anteriorly leading to decrease in profile convexity. The upper and lower face soft tissue height increases and their ratio improved. The upper and lower lip thickness reduced, but upper lip length did not change and lower lip length increased after the treatment. The space between upper and lower lip edge to E - line moved to a normal range and labiomental fold became wider.

Statement of the Problem: Alveolar ridge resorption after tooth extraction may interfere with optimal dental implant placement. Purpose: This study aimed to compare the marginal bone loss (MBL) and thickness of the buccal aspect of the augmented site in Simultaneous versus delayed implant placement following lateral ramus horizontal ridge augmentation in the posterior mandible. Materials and Method: This prospective cohort study was conducted on patients who required horizontal bone augmentation of the posterior mandible using lateral ramus au-togenous bone graft. Patients were divided into two groups of Simultaneous implant placement (group 1) and delayed implant placement (group 2). Cone-beam computed tomography (CBCT) images were obtained before augmentation, at the time of implant placement, and 10 months later (6 months after implant loading). MBL and thickness of the buccal aspect were evaluated over time. Results: There were 18 patients in the group 1 and 16 patients in the group 2. Analysis of the CBCT scans demonstrated that the mean MBL was 1. 21±, 0. 35mm in the group 1 and 1. 08±, 0. 19mm in the group 2, with no significant difference between the two groups (p= 0. 19). Thickness of the buccal aspect of the augmented site at the time of implant place-ment was 1. 85±, 0. 20mm in the group 1 and 2. 16±, 0. 29 mm in the group 2, with a signifi-cant difference (p< 0. 001). However, data analysis regarding changes in the buccal plate thickness showed no significant difference between the two groups (p= 0. 36). Conclusion: According to the results of this study, there was no significant difference in M-BL and post-operative changes in the thickness of the buccal aspect of the augmented sites with onlay lateral ramus bone blocks between Simultaneous and delayed implant placement.

Background and Aims: Functional therapy locates the mandible in a more anterior and inferior position. Tongue posture and oropharynx space have a considerable relationship with mandibular posture. The aim of the present study was to determine the changes of tongue posture and oropharynx space following treatment with Twin block appliance in adolescent patients with class II division 1 ma1occlusion. Materials and Methods: Twenty two patients (14 girls mean age: 11. 5, 8 boys mean age: 12. 5 years) who were treated with twin-block appliance were enrolled. Cephalograms were used to assess the linear measurements. Graber pattern and McNamara parameter were used to evaluate the tongue posture and oropharynx space, respectively. Data analysis was performed by paired t-test. Results: The findings of the present study showed a significant increase in anterior position of tongue (P=0. 06). Oropharynx space was increased significantly (P<0. 001). There was a significant correlation between the decrease of ANB and anteroposterior increase of oropharynx space. Conclusion: Twin-block appliance caused considerable forward movement of tongue and significant increase of oropharynx space in the sagittal plan.

Subspace Pursuit (SP) is an efficient algorithm for sparse signal reconstruction. When the interested signal is block sparse, i.e., the nonzero elements occur in clusters, block sparse recovery algorithms are developed. In this paper, a blocked algorithm based on SP, namely block SP (BSP) is presented. Contrary to the previous algorithms such as block Orthogonal Matching Pursuit (BOMP) and mixed l2/l1-norm, our approach presents better recovery performance and requires less time when non-zero elements appear in fixed blocks in a particular hardware in most of the cases. It is demonstrated that our proposed algorithm can precisely reconstruct the blocksparse signals, provided that the sampling matrix satisfies the block restricted isometry property - which is a generalization of the standard RIP widely used in the context of compressed sensingwith a constant parameter. Furthermore, it is experimentally illustrated that the BSP algorithm outperforms other methods such as SP, mixed l2/l1-norm and BOMP. This is more pronounced when the block length is small.

Aim: The purpose of this study was to compare the clinical effectiveness of the mandibular infiltration versus the mandibular block for the operative and surgical treatment of primary molars.Methods & Materials: 80 children aged 6-9 years old who required bilateral identical dental treatment in mandibular primary molars were selected. Subjects received an infiltration on one side of mandible and blockon the other. Bilateral identical procedure was performed on each patients during the same appointment. These procedures included amalgam restoration, pulpotomy, extraction, stainless steel crown. Sign of discomfort included hand and body tension, eye movement indicating pain, verbal complaints and tears. Both techniques were evaluated blindly by a single rater who was not the operator.Result: T test indicated there was no significant difference between block and infiltration for any of the factors evaluated and anesthesia profundity is not as dependent upon bone density Conclusion: Mandibular infiltration can be used versus block in treating mandibular primary molars.