A new optical trapping design to transport gold nanoparticles using a PANDA ring resonator system is proposed. Intense optical fields in the form of dark solitons controlled by Gaussian pulses are used to trap and transport nanoscopic volumes of matter to the desired destination via an optical waveguide. Theoretically, the gradient and scattering forces are responsible for this trapping phenomenon, where in practice such systems can be fabricated and a thin-film device formed on the specific artificial medical materials, for instance, an artificial bone. The dynamic behavior of the tweezers can be tuned by controlling the optical pulse input power and parameters of the ring resonator system. Different trap sizes can be generated to trap different gold nanoparticles sizes, which is useful for gold nanoparticle therapy. In this paper, we have shown the utility of gold nanoparticle trapping and delivery for therapy, which may be useful for cosmetic therapy and related applications.
gold nanoparticle trapping; particle trapping; therapy; transport
A novel nanomicro syringe system was proposed for drug storage and delivery using a PANDA ring resonator and atomic buffer. A PANDA ring is a modified optical add/drop filter, named after the well known Chinese bear. In principle, the molecule/drug is trapped by the force generated by different combinations of gradient fields and scattering photons within the PANDA ring. A nanomicro needle system can be formed by optical vortices in the liquid core waveguide which can be embedded on a chip, and can be used for long-term treatment. By using intense optical vortices, the required genes/molecules can be trapped and transported dynamically to the intended destinations via the nanomicro syringe, which is available for drug delivery to target tissues, in particular tumors. The advantage of the proposed system is that by confining the treatment area, the effect can be decreased. The use of different optical vortices for therapeutic efficiency is also discussed.
nanomicro syringe; nanomicro needle; molecular therapy; therapeutic efficiency; cancer
De Quervain disease is a mechanical tenosynovitis due to inadequacy volume between abductor pollicis longus, extensor pollicis brevis and their tunnel. Treatment methods include immobilization, steroid injections, and operation. For the first time Fritz De Quervain described surgical treatment of this disease. Since then, various ways of treatment have been reported. The purpose of this study is to compare the clinical outcomes of a longitudinal incision with a transverse incision in De Quervain disease.
This was a randomized controlled clinical trial conducted in three hospitals in Iran, Yazd from March 2003 to September 2008. One hundred-twenty patients with De Quervain disease who did not respond to conservative treatment were operated with two different incisions. The patients were followed for three months to compare the surgical outcomes.
During a three month follow-up, a significant difference was shown between the two methods (p=0.03). Results of surgical treatment with longitudinal incision were excellent (only 5 hypertrophic scars), but there were 13 postoperative complaints with transverse incision.
According to our findings, longitudinal incision in surgical treatment of De Quervain disease is better than transverse incision.
De Quervian disease; Longitudinal incision; Transverse incision; Surgical treatment
We propose a novel drug delivery system (DDS) by using a PANDA ring resonator to form, transmit and receive the microscopic volume by controlling some suitable ring parameters. The optical vortices (gradient optical field/well) can be generated and used to form the trapping tool in the same way as the optical tweezers. The microscopic volume (drug) can be trapped and moved (transported) dynamically within the wavelength router or network. In principle, the trapping force is formed by the combination between the gradient field and scattering photons, which has been reviewed. The advantage of the proposed system is that a transmitter and receiver can be formed within the same system, which is called transceiver, in which the use of such a system for microscopic volume (drug volume) trapping and transportation (delivery) can be realized.
(140.7010) Laser trapping; (350.4855) Optical tweezers or optical manipulation; (080.4865) Optical vortices; (140.4780) Optical resonators; (190.4360) Nonlinear optics, devices
Obesity, in the past was perceived to be the problem of the rich, but recent studies have reported that the problem of obesity is a worldwide problem and rural population is no less affected. Self-perceived health and weight appropriateness is an important component of weight-loss and eating behaviors and may be mediated by local, social and cultural patterning. In addition to the quality of life assessment, it should therefore be an important focal point for the design and implementation of clinical and public health policies.
The present study was carried out to assess the self-perception of weight appropriateness as well as the quality of life of overweight and obese individual among the rural population particularly among housewives. A total of 421 respondents participated in the study which consisted of 36.6% in the overweight and 63.4% in the obese categories.
the analysis of the survey revealed that self-perception regarding obesity among respondents show common similarities, particularly in self reporting on health, dietary habit and also the concept of beauty and a beautiful body. Character and behavior are highly regarded in evaluating a person’s self-worth in society. The results on the quality of life using the ORWELL 97 instrument show that the quality of life of respondents was moderate. Most of the respondents were aware of their body weight and indicated an intention to lose weight but also reported themselves as healthy or very healthy.
The results of the survey indicated that perception on obesity did not differed very much between respondents, in fact there existed a lot of similarities in their perception about health, quality of life, personal health and self-satisfaction with own body. However, their quality of life was within the normal or moderate level based on the ORWELL 97 assessment. Even though most of the respondents were aware of their body weight and indicated an intention to lose weight they also reported themselves as healthy or very healthy, suggesting that public health messages intended for rural housewives need to be more tailored to health-related consequences of fatness.
Overweight; Obesity; Quality of life; Self-perception; Rural housewives
The generation of vascular progenitors (VP) from human induced pluripotent stem cells (hiPSC) has great potential for treating vascular disorders such as ischemic retinopathies. However, long-term in vivo engraftment of hiPSC-derived VP into retina has not yet been reported. This goal may be limited by the low differentiation yield, greater senescence, and poor proliferation of hiPSC-derived vascular cells. To evaluate the potential of hiPSC for treating ischemic retinopathies, we generated VP from a repertoire of viral-integrated and non-integrated fibroblast and cord blood (CB)-derived hiPSC lines, and tested their capacity for homing and engrafting into murine retina in an ischemia-reperfusion (I/R) model.
Methods and Results
VP from human embryonic stem cells (hESC) and hiPSC were generated with an optimized hemato-vascular differentiation system. FACS-purification of human embryoid body (hEB) cells differentially expressing endothelial/pericytic markers identified a CD31+ CD146+ VP population with high vascular potency. Episomal CB-iPSC generated these VP with higher efficiencies than fibroblast-iPSC. Moreover, in contrast to fibroblast-iPSC-VP, CB-iPSC-VP maintained expression signatures more comparable to hESC-VP, expressed higher levels of immature vascular markers, demonstrated less culture senescence and sensitivity to DNA damage, and possessed fewer transmitted reprogramming errors. Luciferase transgene-marked VP from hESC, CB-iPSC, and fibroblast-iPSC were injected systemically or directly into the vitreous of retinal I/R-injured adult NOD-SCID mice. Only hESC- and CB-iPSC-derived VP reliably homed and engrafted into injured retinal capillaries, with incorporation into damaged vessels for up to 45 days.
VP generated from CB-iPSC possessed augmented capacity to home, integrate into, and repair damaged retinal vasculature.
Human induced pluripotent cells; embryonic stem cells; progenitor; endothelial differentiation; vasculature; retinopathy; ischemia-reperfusion; transplantation
Low temperature during germination and early seedling growth is one of the most significant limiting factors in the productivity of plants. Tomato seedling germination is sensitive to chilling stress. Gamma-aminobutyric acid (GABA), as a non-protein amino acid, involved in various stress tolerances in plants. In this study, 5-day old tomato seedlings were exposed to chilling stress (2 ± 0.05 °C for 48 h) and then the effects of 0, 100, 250, 500 and 750 μmolL−1 concentrations of GABA on electrolyte leakage, proline and malondialdehyde (MDA) content were investigated. The resultS showed that the antioxidant enzyme activity, electrolyte leakage, MDA and proline content were significantly reduced by GABA treatments. However under chilling stress seedlings treated with GABA exhibited significantly higher sugar and proline contents as compared to un-treated seedlings. These results suggest that GABA treatment protects tomato seedlings from chilling stress by enhancing some antioxidant enzymes activity and reducing MDA content which results in maintaining membrane integrity.
Tomato seedling; Gamma-aminobutyric acid; Chilling stress; Antioxidant enzyme
Plasma fibronectin (pFn) has long been suspected to be involved in hemostasis; however, direct evidence has been lacking. Here, we demonstrated that pFn is vital to control bleeding in fibrinogen-deficient mice and in WT mice given anticoagulants. At the site of vessel injury, pFn was rapidly deposited and initiated hemostasis, even before platelet accumulation, which is considered the first wave of hemostasis. This pFn deposition was independent of fibrinogen, von Willebrand factor, β3 integrin, and platelets. Confocal and scanning electron microscopy revealed pFn integration into fibrin, which increased fibrin fiber diameter and enhanced the mechanical strength of clots, as determined by thromboelastography. Interestingly, pFn promoted platelet aggregation when linked with fibrin but inhibited this process when fibrin was absent. Therefore, pFn may gradually switch from supporting hemostasis to inhibiting thrombosis and vessel occlusion following the fibrin gradient that decreases farther from the injured endothelium. Our data indicate that pFn is a supportive factor in hemostasis, which is vital under both genetic and therapeutic conditions of coagulation deficiency. By interacting with fibrin and platelet β3 integrin, pFn plays a self-limiting regulatory role in thrombosis, suggesting pFn transfusion may be a potential therapy for bleeding disorders, particularly in association with anticoagulant therapy.
The aim of this study was to evaluate the cytotoxic effects of fiber reinforced composite bonded retainers in comparison with flexible spiral wires (FSWs) under high and low cariogenic-simulated environments using human oral fibroblasts.
Materials and Methods:
Four types of bonded retainers were evaluated: (1) reinforced with glass fibers: Interlig (Angelus), (2) reinforced with polyethylene fibers: Connect (Kerr), (3) reinforced with quartz fibers: Quartz Splint UD (RTD), and (4) FSW. Twenty specimens of each sample group were prepared with the same surface area and halved. Next, half of them were placed in a high cariogenic environment 60 min in 10% lactic acid 3 times a day and remained in Fusayama Meyer artificial saliva for the rest of the day) and the other half were placed in a low cariogenic environment 20 min in 10% lactic acid 3 times a day and remained in Fusayama Meyer artificial saliva for the rest of the day) for 1, 7 and 30 days. Cell viability was assessed by MTT assay. Data were analyzed using SPSS software (α =0.05).
During the 1st month, cytotoxicity reduced gradually. In the low cariogenic-simulated environment, the cytotoxicity of all of the groups were reported to be mild at day 30 and the difference between them was significant (P = 0.016). In the same period in the high cariogenic-simulated environment, the cytotoxicity of Connect and Quartz Splint was mild, and they had lower cytotoxicity than the other groups. Meanwhile, Interlig had moderate (52%) and FSW had severe cytotoxicity (22%) and the difference between the groups was also significant (P = 0.000).
FSW retainers are not recommended in those at high-risk for dental caries. However, in those at low-risk, there is no difference from the standpoint of cytotoxicity.
Cell viability; cytotoxicity; fiber reinforced composite; retainer
Radio-protectors are agents that protect human cells and tissues from undesirable effects
of ionizing radiation by mainly scavenging radiation-induced free radicals. Although
chemical radio-protectors diminish these deleterious side effects they induce a number
of unwanted effects on humans such as blood pressure modifications, vomiting, nausea,
and both local and generalized cutaneous reactions. These disadvantages have led to
emphasis on the use of some botanical radio-protectants as alternatives. This review has
collected and organized studies on a plant-derived radio-protector, lycopene. Lycopene
protects normal tissues and cells by scavenging free radicals. Therefore, treatment of
cells with lycopene prior to exposure to an oxidative stress, oxidative molecules or ionizing
radiation may be an effective approach in diminishing undesirable effects of radiation
byproducts. Studies have designated lycopene to be an effective radio-protector with
negligible side effects.
Antioxidant; Carotenoid; Free Radical; Lycopene; Radioprotectant
Background: The aim of this study was to evaluate the electromyographic
(EMG) activity of the two leg muscles (Tibialis anterior [TA] and Soleus [SOL]) during
ascending and descending stairs with different heights (10 cm, 15.5 cm and 18 cm).
Methods: Eighteen female university students aged between 20 and 36 yr
participated in the study. Data were collected using a ME6000 Biomonitor EMG System
(revision MT-M6T16-0) and surface electrodes.
Results: The EMG activity of the SOL muscle was significantly higher than
the TA muscle activity (P = 0.001). Besides, the muscle activity level of the SOL muscle
was significantly higher when ascending compared to descending condi-tion (P = 0.001). The
stair height had no significant effect of the EMG activity of the two muscles.
Conclusion: These findings highlight that the two muscles are not equally
affected by the stair height during ascending and descending condition. The results also
indicate that there is no preference between different stair heights in terms of muscular
Stair height; Stair gait; Electromyographic
Purpose: It is estimated that one third of the world’s population were infected with M. tuberculosis, but only 10% of them have developed in to disease form. This subject refers to differences in host immune system activity against the tuberculosis. Vitamin D and its receptor (VDR) are important factors in the host innate immune system against the tuberculosis. In the present study VDR gene polymorphisms and its relationship with plasma vitamin D levels in susceptibility to tuberculosis have been investigated.
Methods: The subjects were 84 patients with tuberculosis and 90 healthy controls. Vitamin D levels were measured in all study participants. DNA was isolated from the blood leukocytes of all groups and amplified by polymerase chain reaction (PCR). Then restriction fragment length polymorphism (RFLP) was performed on each PCR products to study the VDR gene polymorphisms. The statistical analyses were conducted using SPSS.
Results: There was no statistically significant relationship between polymorphisms of FokI, BsmI, ApaI and TaqI in VDR gene and susceptibility to tuberculosis. Vitamin D deficiency and susceptibility to tuberculosis were closely related (95% CI -0.08 – 4.7, P = 0.059). Also the relationship between plasma vitamin D levels and frequency of FokI-ff gene polymorphism was significant in all study participants (P = 0.045).
Conclusion: When the genotype frequencies of VDR gene polymorphisms were analyzed with respect to plasma vitamin D levels, a significant association was seen. As an enhancement in plasma vitamin D levels in individuals (with FokI-ff genotype and low levels of vitamin D) may protect them against active tuberculosis.
Tuberculosis; Polymorphism; Genetics; 25-hydroxyvitamin D
One of the key parameters in Fluidized Bed reactors is the control of biofilm thickness and configuration. The effect of upflow velocity on performance and biofilm characteristics of an Anaerobic Fluidized Bed Reactor was studied in treating Currant wastewater at various loading rates. The reactor used this study was made of a plexiglass column being 60 mm diameter, 140 cm height, and a volume of 3.95 L. The results demonstrated that the AFBR system is capable of handling an exceptionally high organic loading rate. At organic loading rates of 9.4 to 24.2 (kg COD m−3) at steady state, reactor performances with upflow velocities of 0.5, 0.75 and 1 (m min−1) were 89.3- 63.4, 96.9 – 79.6 and 95 – 73.4 percent, respectively. The average biomass concentration per unit volume of the AFBR (as gVSSatt L−1 expended bed) decreased with the increase of upflow velocity in the range of 0.5–1 m min−1 at all applied organic loading rates. The total biomass in the reactor increased with increases in the organic loading rate. The peak biomass concentration per unit volume (as gVSSatt L−1 expended bed) was observed at the bottom part of the reactor, then it droped off slowly towards the top. The biofilm thickness increased from the bottom to the top of the reactor representing a stratification of the media in the AFBR. The bed porosity increased from the bottom to the top of the reactor.
Biofilm characteristics; Biomass concentration; Anaerobic Fluidized Bed Reactor; Currant wastewater; Upflow velocity
Cardiovascular disease linked to atherosclerosis is the leading cause of death worldwide. Atherosclerosis is mainly linked to dysfunction in vascular endothelial cells and subendothelial accumulation of oxidized forms of LDL. In the present study, we investigated the role of myeloperoxidase oxidized LDL (Mox-LDL) in endothelial cell dysfunction. We studied the effect of proinflammatory Mox-LDL treatment on endothelial cell motility, a parameter essential for normal vascular processes such as angiogenesis and blood vessel repair. This is particularly important in the context of an atheroma plaque, where vascular wall integrity is affected and interference with its repair could contribute to progression of the disease. We investigated in vitro the effect of Mox-LDL on endothelial cells angiogenic properties and we also studied the signalling pathways that could be affected by analysing Mox-LDL effect on the expression of angiogenesis-related genes. We report that Mox-LDL inhibits endothelial cell motility and tubulogenesis through an increase in miR-22 and heme oxygenase 1 expression. Our in vitro data indicate that Mox-LDL interferes with parameters associated with angiogenesis. They suggest that high LDL levels in patients would impair their endothelial cell capacity to cope with a damaged endothelium contributing negatively to the progression of the atheroma plaque.
Three-dimensional (3D) topological insulator (TI) has been conjectured as an emerging material to replace copper (Cu) as an interconnect material because of the suppression of elastic scattering from doping and charge impurities for carrier transport on TI surface. We, therefore via full real-space simulation, examine the feasibility of using thin 3D-TI (Bi2Se3) wire for the local electrical interconnects in the presence of edge roughness, vacancies, acoustic phonons and charge impurities across temperature and Fermi-level by simulating quantum transport through Non-Equilibrium Green Function algorithm. We found that because of the scattering induced by the acoustic phonons, the mobility reduces considerably at the room temperature which complemented with the low density of states near Dirac-point does not position Bi2Se3 3D-TI as a promising material to replace Cu for local interconnects. Properties required in suitable TI material for this application have also been discussed.
Urease belongs to a family of highly conserved urea-hydrolyzing enzymes. A common feature of these enzymes is the presence of two Lewis acid nickel ions and reactive cysteine residue in the active sites. In the current study we examined a series of biscoumarins 1–10 for their mechanisms of inhibition with the nickel containing active sites of Jack bean and Bacillus pasteurii ureases. All these compounds competitively inhibited Jack bean urease through interaction with the nickel metallocentre, as deduced from Michaelis-Menten kinetics, UV-visible absorbance spectroscopic, and molecular docking simulation studies. Some of the compounds behaved differently in case of Bacillus pasteurii urease. We conducted the enzyme kinetics, UV-visible spectroscopy, and molecular docking results in terms of the known protein structure of the enzyme. We also evaluated possible molecular interpretations for the site of biscoumarins binding and found that phenyl ring is the major active pharmacophore. The excellent in vitro potency and selectivity profile of the several compounds described combined with their nontoxicity against the human cells and plants suggest that these compounds may represent a viable lead series for the treatment of urease associated problems.
The prevalence of multidisciplinary teams (MDT) for the delivery of cancer care is increasing globally. Evidence exists of benefits to patients and healthcare professionals. However, MDT working is time and resource intensive. This study aims to explore members’ views on existing practices of urology MDT working, and to identify potential interventions for improving the efficiency and productivity of the MDT meeting.
Members of urology MDTs across the UK were purposively recruited to participate in an online survey. Survey items included questions about the utility and efficiency of MDT meetings, and strategies for improving the efficiency of MDT meetings: treating cases by protocol, prioritising cases, and splitting the MDT into subspeciality meetings.
173 MDT members participated (Oncologists n = 77, Cancer Nurses n = 54, Urologists n = 30, other specialities n = 12). 68% of respondents reported that attending the MDT meeting improves efficiency in care through improved clinical decisions, planning investigations, helping when discussing plans with patients, speciality referrals, documentation/patient records. Participants agreed that some cases including low risk, non-muscle invasive bladder cancer and localised, low-grade prostate cancer could be managed by pre-agreed pathways, without full MDT review. There was a consensus that cases at the MDT meeting could be prioritised by complexity, tumour type, or the availability of MDT members. Splitting the MDT meeting was unpopular: potential disadvantages included loss of efficiency, loss of team approach, unavailability of members and increased administrative work.
Key urology MDT members find the MDT meeting useful. Improvements in efficiency and effectiveness may be possible by prioritising cases or managing some low-risk cases according to previously agreed protocols. Further research is needed to test the effectiveness of such strategies on MDT meetings, cancer care pathways and patient outcomes in clinical practice.
Urology; Multidisciplinary; Team; Decision-making; Efficacy; Efficiency
Band-alignment induced current modulation in Bi2Se3 three-dimensional topological insulator slab has been investigated by quantum transport simulations for three different device designs, one for purely lateral transport and other two with vertical transport. Non-Equilibrium Green Function formalism has been deployed to understand the transport mechanism in band-alignment devices to appraise the possibility of a 3D-TI based resonant device. A resonance condition is observed when the Dirac-points (bands) are aligned. This results in the maximum current at resonance for the design with only lateral transport. However, current ratio between resonant and non-resonant condition is found to be relatively small and strong temperature dependence is also noticed. The other two designs with vertical transport have degraded transfer characteristics, although from state-of-art literature they are expected to manifest nearly an ideal resonance peak. The physical insights for these observations have been posited along with the suggestions for attaining close to an ideal operation for the first design, which we also suggest for the pursuit in the future for spintronic oscillators and analog multipliers based on band-alignment induced resonance.
Les anévrysmes de l'artère hépatique sont rares et pourvoyeurs de complications graves. La pancréatite est reste une mode de révélation inhabituel. À travers une observation d'un anévrysme de l'artère hépatique propre et les auteurs font une mise au point sur les anévrysmes de l'artère hépatique, les auteurs discutent le rôle de la chirurgie et le rétablissement du flux hépatique artériel dans le traitement de ces lésions vasculaires.
Anévrysme; artère hépatique; chirurgie; embolisation; aneurysm; hepatic artery; surgery; embolization
Pulmonary metastasectomy for sarcoma is a widely accepted practice. Nevertheless, no previous studies has been reported the outcomes following metastasectomy compared with chemotherapy for patients with resectable and isolated pulmonary metastases. Our aim is to compare these modalities for the subset of patients with resectable metastases. Furthermore, the outcomes for patients with unresectable lung metastases are reported.
Sarcoma patients with isolated lung metastases were identified and their computed axial tomography scans were reviewed by a thoracic surgeons' committee. Patients were divided into three groups: A: patients with resectable metastases treated with metastasectomy (n = 29), B: patients with resectable metastases who received systemic therapy (n = 17) and C: patients with unresectable metastases (n = 25). Survival outcomes were plotted and compared through log-rank test for osteosarcoma and non-osteosarcoma patients.
Seventy-one patients (32 with osteosarcoma and 39 with non-osteosarcoma) were eligible. Progression-free survival (PFS) was superior in patients who belonged to Group A compared with Groups B and C (8.0, 4.3 and 2.2 months, respectively, P = 0.0002). Furthermore, overall survival (OS) was superior in patients who belonged to Group A compared with Groups B and C (39.6, 20.0 and 7.8 months, respectively, P < 0.0001). A subanalysis for osteosarcoma patients showed superior PFS and OS for Group A vs B (median PFS 21.6 and 3.65 months, respectively, P = 0.011 and median OS 34.0 and 12.4 months, respectively, P = 0.0044). For non-osteosarcoma patients, there were no such significant survival differences between Groups A and B. Overall, patients who belonged to Group A had significantly lower mean percentage of their follow-up time spent admitted at hospital, and a trend towards lower requirements for home oxygen therapy.
Pulmonary metastasectomy is associated with improved survival of osteosarcoma patients with resectable lung metastases. For non-osteosarcoma patients, the survival benefit of metastasectomy over chemotherapy is uncertain and warrants further evaluation. Patients with unresectable metastases have poor prognosis.
Sarcoma; Lung; Metastasis; Metastasectomy
Obese subjects are at risk of multiple comorbidities including stroke and coronary heart disease (CHD), which is partly due to disturbances in the hemostatic system.
The aims of the present study were to determine the effects of a weight-loss program on fibrinogen and fibrinolytic markers.
Materials and Methods:
Twenty-eight obese subjects were involved in a weight-loss program consisted of exercise and nutritional education for 12-weeks duration. Physical parameters were documented and blood specimen was tested at pre and post-intervention for fibrinogen, tissue plasminogen activator (t-PA), plasminogen activator inhibitor-1 (PAI-1), and thrombin activatable fibrinolysis inhibitor (TAFI). Paired t-test was used for statistical analysis.
There was a significant decline in the levels of t-PA, PAI-I, TAFI and fibrinogen following the weight-loss program (P < 0.01 for each). A significant positive correlation between tPA levels and body weight, body mass index (BMI), waist circumference, and fat-free mass were found. There was also a significant correlation betwen BMI and other blood parameters.
Reduced fibrinogen, fibrinolytic, and physical parameters were demonstrated in obese subjects following the weight reduction program. These findings suggest the possible beneficial effects of this program on the hemostatic burden particularly on the fibrinolytic biomarkers.
Exercise; Fibrinogen; Obese; Plasminogen activator; Plasminogen activator inhibitor-1; Thrombin activatable fibrinolysis inhibitor
Wireless mesh networking is a promising technology that can support numerous multimedia applications. Multimedia applications have stringent quality of service (QoS) requirements, i.e., bandwidth, delay, jitter, and packet loss ratio. Enabling such QoS-demanding applications over wireless mesh networks (WMNs) require QoS provisioning routing protocols that lead to the network resource underutilization problem. Moreover, random topology deployment leads to have some unused network resources. Therefore, resource optimization is one of the most critical design issues in multi-hop, multi-radio WMNs enabled with multimedia applications. Resource optimization has been studied extensively in the literature for wireless Ad Hoc and sensor networks, but existing studies have not considered resource underutilization issues caused by QoS provisioning routing and random topology deployment. Finding a QoS-provisioned path in wireless mesh networks is an NP complete problem. In this paper, we propose a novel Integer Linear Programming (ILP) optimization model to reconstruct the optimal connected mesh backbone topology with a minimum number of links and relay nodes which satisfies the given end-to-end QoS demands for multimedia traffic and identification of extra resources, while maintaining redundancy. We further propose a polynomial time heuristic algorithm called Link and Node Removal Considering Residual Capacity and Traffic Demands (LNR-RCTD). Simulation studies prove that our heuristic algorithm provides near-optimal results and saves about 20% of resources from being wasted by QoS provisioning routing and random topology deployment.
ILP; wireless mesh networks; random topology; QoS provisioning routing; heuristic algorithm
Cardiovascular diseases are among the most important sources of mortality and morbidity, and have a high disease burden. There are some major well-known risk factors, which contribute to the development of these diseases. Occupational stress is caused due to imbalance between job demands and individual’s ability, and it has been implicated as an etiology for cardiovascular diseases.
This study was conducted to evaluate the cardiovascular risk factors and different dimensions of occupational stress in high-ranking government officials, comparing an age and sex-matched group of office workers with them.
Patients and Methods:
We invited 90 high-ranking officials who managed the main governmental offices in a city, and 90 age and sex-matched office workers. The subjects were required to fill the occupational role questionnaire (Osipow) which evaluated their personal and medical history as well as occupational stress. Then, we performed physical examination and laboratory tests to check for cardiovascular risk factors. Finally, the frequency of cardiovascular risk factors and occupational stress of two groups were compared.
High-ranking officials in our study had less work experience in their current jobs and smoked fewer pack-years of cigarette, but they had higher waist and hip circumference, higher triglyceride level, more stress from role overload and responsibility, and higher total stress score. Our group of office workers had more occupational stress because of role ambiguity and insufficiency, but their overall job stress was less than officials.
The officials have higher scores in some dimensions of occupational stress and higher overall stress score. Some cardiovascular risk factors were also more frequent in managers.
Cardiovascular Risk Factor; Burnout, Professional; Managers
Background: Musculoskeletal disorders are among the most prevalent occupational disorders in different jobs such as office work. Some interventions such as ergonomic modifications and workplace exercises are introduced as the methods for alleviating these disorders. In this study we compared the effect of ergonomic modifications and workplace exercises on musculoskeletal pain and discomfort in a group of office workers.
Methods: In an interventional study on office workers, the effect of two interventions was compared. Ergonomic modification consisted of correcting the arrangement of workstation and changing some equipment; workplace exercises included stretching exercises focusing on neck, shoulders, low back, and hand and wrist. Musculoskeletal complaints were assessed and compared before and after 1 month interventions.
Results: The frequency of musculoskeletal complaints was high before the study. Both interventions significantly reduced complaints in a similar manner except for low back pain which was reduced in exercise group more than the other group.
Conclusion: In this study we found a beneficial short-term effect for both ergonomic modifications and stretching work-place exercises on reducing musculoskeletal pain in office workers.
Musculoskeletal diseases; Ergonomic modification; Stretching exercises; Office worker