Effective optimization using sample persistence: A case study on quantum annealers and various Monte Carlo optimization methods

We present and apply a general-purpose, multistart algorithm for improving the performance of low-energy samplers used for solving optimization problems. The algorithm iteratively fixes the value of a large portion of the variables to values that have a high probability of being optimal. The resulting problems are smaller and less connected, and samplers tend to give better low-energy samples for these problems. The algorithm is trivially parallelizable since each start in the multistart algorithm is independent, and could be applied to any heuristic solver that can be run multiple times to give a sample. We present results for several classes of hard problems solved using simulated annealing, path-integral quantum Monte Carlo, parallel tempering with isoenergetic cluster moves, and a quantum annealer, and show that the success metrics and the scaling are improved substantially. When combined with this algorithm, the quantum annealer's scaling was substantially improved for native Chimera graph problems. In addition, with this algorithm the scaling of the time to solution of the quantum annealer is comparable to the Hamze-de Freitas-Selby algorithm on the weak-strong cluster problems introduced by Boixo et al. Parallel tempering with isoenergetic cluster moves was able to consistently solve three-dimensional spin glass problems with 8000 variables when combined with our method, whereas without our method it could not solve any.

Correlation of occurrence of infection in burn patients

The study of burn flora is helpful in determining current antibiotic susceptibilities and locating development of multidrug resistant bacterial strains among the unit's usual flora. In this study, we aimed to determine the bacteriological pattern of blood, urine and sputum infections and their correlation with burn wound infections. We used data from our burn registry program. All data on demographics, burn wounds and burn wound infection, bacteria isolated, sensitivity to different antibiotics, burn wound culture, sputum culture, urine culture and catheter tip culture were recorded. We had 1721 hospitalized burn patients. Mean age was 26.3+/-20.25 years old. Mean hospital stay was 14.41 days (range 0-64 days). Mean (SD) TBSA was 16.48 (20.67) years. Mortality rate was 5.9%. Burn wound infection was present in 38.54%. The most frequent species was Staphylococcus spp. (55.1%), followed by Pseudomonas (14.29%), Enterococcus (12.24%), E. coli (4%), Klebsiella and Proteus (both 2%). Urine culture was positive in 27.9%, sputum culture was positive in 1.14%, catheter tip culture was positive in 12.3% and blood culture was positive in 7.6% of the cases. There were correlations between positive wound culture and blood and urine culture, most of them with one bacteria species. The most frequent disseminated bacteria was Pseudomonas aeruginosa and the most sensitive antibiotic was Amikacin. More than 39.2% of our positive culture patients had 3 or more positive cultures, and 36.5% had similar culture results for one bacteria, which was a sign of disseminated infection.

LA50 in burn injuries

Burn injuries put a huge financial burden on patients and healthcare systems. They are the 8th leading cause of mortality and the 13th most common cause of morbidity in our country. We used data from our Burn Registry Program to evaluate risk factors for mortality and lethal area fifty percent (LA50) in all burn patients admitted over two years. We used multiple logistic regressions to identify risk factors for mortality. LA50 is a reliable aggregate index for hospital care quality and a good measure for comparing results, also with those of other countries. 28,690 burn patients sought medical attention in the Emergency Department, and 1721 of them were admitted. Male to female ratio was 1,75:1. 514 patients were under 15 years old. Median age was 25 (range: 3 months - 93 years). Overall, probability of death was 8.4%. LA50 was 62.31% (CI 95%: 56.57-70.02) for patients aged 15 and over and 72.52% (CI 95%: 61.01-100) for those under 15. In the final model, we found that Adjusted OR was significant for age, female sex, TBSA and inhalation injury (P < 0.05). LA50 values showed that children tolerate more extensive burns. Female sex, burn size, age and inhalation injury were the main risk factors for death. Authorities should pay special attention to these variables, especially in prevention programs, to reduce mortality and improve patient outcome. Children have better outcome than adults given equal burn size. Suicide rates are higher for women than men in our country.

Financial burden of burn injuries in iran: a report from the burn registry program

Understanding the cost of burn treatment is very important for patients, their families, governmental authorities and insurance companies. It alleviates patient and familial stress, provides a framework for better use of resources, and facilitates better performance between burn centers. Hospital burn costs can provide a basis for authorities to budget for acute burn treatment, for further management of chronic complications, and for planning prevention and public educational programs in Iran. To identify costs we used data from our burn registry program. Over the two-year assessment period, we treated roughly 28,700 burn patients, 1,721 of whom were admitted, with a mortality rate of 5.9%. The male to female ratio was 1.7:1 (63% male; 37% female). Flame burns were most frequent (49.8%) followed by scalds (35.7%). Mean hospital stay was 14.41 days (range 0-64 days). Mean TBSA was 17.39%. Skin grafts were carried out in 65.4% of the patients, with a mean of 5.2 surgeries per patient. The total cost of all patient admissions over the two years was US$ 4,835,000. The maximum treatment cost for one patient was US$ 91,000. The mean cost per patient was US$ 2,810 (29,500,000 Rials). The mean cost for each percent of burn was US$ 162. The mean cost for a one-day stay in hospital was US$ 195. The mean cost of each operation was US$ 540. Patients who contracted infections endured longer hospital stays, meaning increased costs of US$ 195 per day. With comparable outcome and results, the cost of burn treatment in Iran is cheaper than in the US and Europe.

Epidemiology of outpatient burns in Iran: an update

Burn injury remains a serious and devastating issue faced by developing countries. It is also true, however, that the developed world still tackles many of the challenges caused by burns. In order to reduce this problem through preventive programs, the characteristics of this type of injury must be studied and well documented in each setting. Our study aims to show the epidemiology, demographic distribution and clinical outcomes of burns patients referred to Motahari Burn Hospital, the burn care center that receives the most referrals in Iran. This cross-sectional study, from March 2009 to March 2010, included 6,910 patients with burn injuries who were managed as outpatients. The patient demographics along with the characteristics of the burn injuries and their outcomes were recorded for each case and then evaluated. A total of 6,910 burn patients with a mean ± SD age of 30.20 ± 19.11 years presented to our Emergency Department and were treated as outpatients. Of these, 2,900 were female (41.97%) and 4,010 were male (58.03%). Most of the patients were in the 25-35 year age group, with a prevalence of 1,148 (28.6% of total) males and 716 females (24.7% of total), followed by those aged <15-years-old. Most patients had been burned accidentally. An increase in the instance of self-immolation was identified with an increase in the TBSA burned. Mean follow-up was 30+/-5 months. The results revealed that burns were most likely to occur during housekeeping. Other high risk groups identified were males, those aged from 25 to 35 years-old, and those with lower socio-economic status.

The burn registry program in Iran - First report

Burn injury is still a major problem in Iran, resulting in many reports which are usually dispersed, uncoordinated and probably unreliable. We created a burn registry comprised of a data entry program with 222 variables for each admitted burn patient. This program was established in August 2010 at the Iran University of Medical Sciences, Motahari Burn Hospital. We had 14,277 burn patients from August 2010 to August 2011, 877 of whom were admitted to the hospital. Of the patients, 65.9% were male and 34.1% were female. The age was 28.85 years (SD = 19.77). The most prevalent cause of burn was flame 78.5% (pipe propane gas 57.2; kerosene 19.9%). The mean total body surface area (TBSA) involvement was 23%. A total of 77.8% of patients were discharged with partial recovery, while mortality was 8.9%. The mean hospital stay was 14.63 days (SD =11.07). The program is designed to help understand the scope of burn injury in Iran, providing information on patients, etiology, and course of treatment. It also highlights differences between various parts of the country in terms of the causes and frequency of burn injuries. Moreover, the burn registry provides a basis for further research and surveys for treatment and preventive programs. Our results showed that, although Emergency Medical Services (EMS) staff are highly capable and well-trained, their coverage seems to be less than 50% and needs to be increased. Marriage status was shown to have no influence on the occurrence of burns, and among our patients, 57.0 % were poorly educated.

Burn wound healing with injection of adipose-derived stem cells: a mouse model study

Stem cells have shown promise with regard to the healing process of burn wounds. However, donor sites for these cells are still under investigation. The aim of this study is to review the efficacy of adipose tissue-derived stem cells (ADSCs) in accelerating wound healing of third degree burns in a mouse model. To this end, forty healthy male inbred Balb/c mice were selected and set up as an experimental model for third degree burn wounds. They were randomly divided into 3 equally sized groups: the ADSCs group, the mechanically prepared adipose tissue group, and the control group. The wounds were examined daily until the mice were sacrificed for tissue sampling in the 3(rd) week. Our results showed that wound surface area and eschar thickness were smaller in the ADSCs group throughout the study period, although there was no significant difference between the groups for decreasing values of wound area characteristics. In terms of wound healing parameters, lymphocyte and macrophage cell counts were larger in the ADSCs group compared to the other groups. Fibroplasia, collagen synthesis and remodeling were more aberrant in this group. However, there was no statistically significant difference in either of these observed differences (p>0.05). Although enzymatically prepared ADSCs seem a potential treatment in wound healing, our study of a mouse model burn wound revealed no significant improvement in using this option.

Silver and zinc oxide nanostructures loaded on activated carbon as new adsorbents for removal of methylene green

In this study, the removal of methylene green (MG) from aqueous solution based on two new adsorbents including silver nanoparticles and zinc oxide nanorods loaded on activated carbon (Ag-NP-AC and ZnO-NR-AC, respectively) has been carried out. The dependency of removal process to variables such as contact time, pH, amount of adsorbents, and initial MG concentration were examined and optimized. It was found that the maximum MG removal percentage was achieved at pH = 7.0 following stirring at 400 r min−1 for 7 and 6 min for Ag-NP-AC and ZnO-NR-AC, respectively. Equilibrium data were well fitted with the Langmuir model having maximum adsorption capacity of 166.7 and 200 mg g−1 for Ag-NP-AC and ZnO-NR-AC, respectively. Thermodynamic parameters of MG adsorption on Ag-NP-AC such as enthalpy and entropy changes, activation energy, sticking probability, and Gibbs free energy changes show the spontaneous and endothermic nature of the removal process. Among different conventional kinetic models, the pseudo second-order kinetics in addition to particle diffusion mechanism is the best and efficient model for the prediction and explanation of experimental data of MG adsorption onto both adsorbents.

Augmenting the expression of NKp44 molecule and the natural killer activity in peripheral blood mononuclear cells from patients with malignant colorectal carcinoma

OBJECTIVE

NKp44 and NKG2D are of the main NK activating receptors involved in recognition and killing of tumors. Here we studied the stimulatory effects of PHA and/or K562 cell line on induction of NKp44 and NKG2D expression and the NK activity of PBMCs from patients with colorectal carcinoma (CRC).

MATERIALS AND METHODS

Peripheral blood samples were collected from 10 patients with CRC. The peripheral blood mononuclear cells (PBMCs) from each patient received a single stimulation with PHA or double stimulation with PHA and irradiated K562 cell line (iK562). The expression of CD56, NKG2D and NKp44 were detected by flowcytometry. The NK activity of PBMCs against a colorectal carcinoma cell line named as SW742 was determined with 51Cr-release assay.

RESULTS

Double stimulation of PBMCs with PHA+iK562 significantly augmented the number CD56(+) cells compared to PHA alone and non-stimulated PBMCs (P<0.000, P<0.0000; respectively). A single stimulation of PBMCs with PHA resulted in an enhancement in NKG2D and NKp44 expression from 16.6±3.3% (for non-stimulated PBMCs) to 42±5.6% and 48.1±3.8% respectively (p<0.05). Double stimulation of PBMCs augmented the NKp44 expression significantly in comparison with single stimulation with PHA (73.6±12%, p<0.05). Double stimulation of PBMCs significantly enhanced the NK activity against SW742 target cells compared to single stimulation with PHA (p<0.05).

DISCUSSION AND CONCLUSION

Our results demonstrated that the mitogen and iK562 exposure to PBMCs can significantly improve NK activity which is co-related to the higher expression of NKp44 and NKG2D. These data may help to improve cancer immunotherapy protocols.

Structure of vomeronasal organ (Jacobson organ) in male Camelus Domesticus Var. dromedaris persica

The vomeronasal organ (VNO) is a tubular structure in the roof of nasal cavity. The important role of this organ is olfaction of sexual odour. In this study, position, anatomical structure and histology of VNO in Iranian camels (camelus domesticus var. dromedaris persica) were determined. Fourteen healthy male camel heads were collected from an industrial slaughterhouse in Tehran, Iran, for anatomical and histological studies (seven each). The length of VNO and width of dental pad and the number and width of palatine crests were measured. For anatomical studies, the mandible was removed, and maxilla and nasal cavity was cut longitudinally and transversely. For histological studies, the mandible was removed, and first 0.5 cm of initial part of VNO was cut. Then, nasal cavity was cut in some segments with 2 cm thickness. The width of VNO was 3.85 ± 0.31 cm and 1.57 ± 0.18 cm in front and distal parts, respectively. The length of VNO was 15.61 ± 0.59 cm. In histological examinations, VNO was surrounded by J-shape hyaline cartilage. The lining epithelium of lateral wall of VNO was originated from respiratory epithelium, while it had an olfactory epithelium origin in the medial wall. Lamina propria and tunica submucosa were a cavernous connective tissue with seromucous gland with abundant of serous secretory units. The lumen of VNO opens into nasal cavity. The presence of olfactory epithelium found in our study indicates an important role for VNO in pheromone perception and beginning of sexual behaviour.

Epidemiology of paediatric burns in Iran

We surveyed the epidemiology of the patients in a tertiary burn care centre (the Motahari Burn Hospital) in Tehran in the 4-yr period 2005-2009. Scalding was the major cause of burn injury for patients under the age of 6, while there were many more flame and electrical burns in late childhood. Males were mainly affected (male to female ratio, 1.7:1). Most burns occurred in the summer, probably due to older children's increased outdoor activities during school vacations. Most of the injuries took place in the kitchen. Age was directly related to the higher total body surface area and mortality rate. Explosion of propane gas at home had a high incidence. Length of hospital stay increased in relation to the burn surface area. Infants were found to be at greatest risk for burn injuries, while older children were at higher risk for severe burns. Before arriving at the hospital, 22 patients had received traditional therapy in the home which was not effective and caused some problems. Pre-hospital care by emergency medicine service personnel was complete and effective. 374 patients had positive results for wound culture (42.9%). The most frequent bacteria found in burn wound cultures was coagulase-negative Staphylococcus (66.8%). Blood culture was positive in 12% of the patients with positive burn wound culture and the most frequent bacteria in blood culture was Pseudomonas aeruginosa. The overall mortality rate was 10.6%. Treatment and prevention programmes should target high risk groups. Important criteria include older age, flame burn, presence of inhalation injury, total body surface area burned above 40%, and sepsis.

Human Bone Marrow-derived Mesenchymal Stem Cell: A Source for Cell-Based Therapy

BACKGROUND

The ability of mesenchymal stem cells (MSCs) to differentiate into many cell types, and modulate immune responses, makes them an attractive therapeutic tool for cell transplantation and tissue engineering.

OBJECTIVE

This project was designed for isolation, culture, and characterization of human marrow-derived MSCs based on the immunophenotypic markers and the differentiation potential.

METHODS

Bone marrow of healthy donors was aspirated from the iliac crest. Mononuclear cells were layered over the Ficoll-Paque density-gradient and plated in tissue cultures dish. The adherent cells expanded rapidly and maintained with periodic passages until a relatively homogeneous population was established. The identification of adherent cells and the immune-surface markers was performed by flow cytometric analysis at the third passage. The in vitro differentiation of MSCs into osteoblast and adipocytes was also achieved.

RESULTS

The MSCs were CD11b (CR3), CD45, CD34, CD31 (PCAM-1), CD40, CD80 (B7-1), and HLA-class II negative because antigen expression was less than 5%, while they showed a high expression of CD90, and CD73. The differentiation of osteoblasts, is determined by deposition of a mineralized extracellular matrix in the culture plates that can be detected with Alizarin Red. Adipocytes were easily identified by their morphology and staining with Oil Red.

CONCLUSION

MSCs can be isolated and expanded from most healthy donors, providing for a source of cell-based therapy.

Endothelial Nitric Oxide Synthase Gene T-786C Polymorphism in Renal Transplant Recipients

BACKGROUND

Nitric oxide (NO) is a major mediator in vascular biology, regulating regional blood flow. NO and the enzymes required for its production contribute to ischemia-reperfusion injury. The T-786C functional polymorphism in the promoter region substantially reduces promoter activity of the endothelial nitric oxide synthase (eNOS) gene and compromises endothelial NO synthesis.

OBJECTIVE

To examine the association between T-786C (rs 2070744) single nucleotide polymorphism (SNP) in eNOS gene and the development of acute rejection in renal transplant patients.

METHODS

60 renal transplant recipients (30 with episodes of acute rejection (ARs) and 30 without rejection (non-ARs)), between June 2008 and March 2010, were included in this study. The polymorphism was determined by PCR-restriction fragment-length polymorphism analysis.

RESULTS

The distribution of the genotypes were TT/TC/CC 60%, 33.4%, 6.6%, and 43%, 46.7%, 13.3% in ARs and non-ARs, respectively (p=0.28). The frequency of T-allele was 76.7% and 66.3%; and for C-allele was 66.6% and 33.3% in ARs and non-ARs, respectively (p=0.09). There were no significant associations between these polymorphisms and acute and chronic kidney allograft rejection.

CONCLUSION

We could not detect any significant association between polymorphism in T-786C of eNOS gene and the development of acute rejection.

A basic neural traffic noise prediction model for Tehran's roads

We present an artificial neural network model to predict hourly A-weighted equivalent sound pressure levels (L(Aeq,1h)) for roads in Tehran at distances less than 4 m from the nearside carriageway edge. Our model uses the UK Calculation of Road Traffic Noise (CORTN) approach. Data were obtained from 50 sampling locations near five roads in Tehran at nearside carriageway edge distances of less than 4 m. The data were randomly assigned to training, testing, and holdout subsets. Model training was carried out using the training and testing subsets and comprised 60% and 20% of the data, respectively. Model validation was performed using the remaining 20% of data as a holdout subset. We examine the overall model efficiency using non-parametric tests, such as the Wilcoxon matched-pairs signed-rank test for the training step and the Kolmogorov-Smirnov test for two independent samples for the validation step. Our results indicate that a neural network approach can be applied for traffic noise prediction in Tehran in a statistically sound manner. The Wilcoxon matched-pairs signed-ranks test detects no significant difference between the absolute testing set errors of the developed neural network and a calibrated version of the CORTN model.

Effectiveness of integrative and instrumental reminiscence therapies on depression symptoms reduction in institutionalized older adults: an empirical study

OBJECTIVE

Reminiscence therapy is a psychological intervention which is specifically designed to address issues of particular relevance to older adults, such as depression. The latest approach to the research on therapeutic utility of reminiscence is gaining popularity among researchers and practitioners, and has yielded promising results. Specifying different types of reminiscence is a crucial component of the approach. The aim of this study was to examine the therapeutic effectiveness of integrative and instrumental types of reminiscence for the treatment of depression in institutionalized older adults dwelling in a nursing home.

METHOD

The study employed a three-group pre-post-test design with random allocation to instrumental or integrative reminiscence or an active social discussion control condition. Twenty-nine institutionalized older adults (12 men and 17 women) with depressive symptoms varying from mild to severe constituted the sample. The interventions were implemented in a short-form group format.

FINDINGS

Analysis of changes from pre-test to post-test revealed that integrative reminiscence therapy led to statistically significant reduction in symptoms of depression in contrast with the control group. Although instrumental reminiscence therapy also reduced depressive symptoms, this improvement was not statistically significant compared to the control group.

CONCLUSION

This study provides additional support for the effectiveness of integrative reminiscence therapy as an intervention for depressed older adults living in residential care settings. This study also provides support for the hypothesis that certain types of reminiscence produce their own specific effects.