Minimum spanning trees made easier via multi-objective optimization

Many real-world problems are multi-objective optimization problems and evolutionary algorithms are quite successful on such problems. Since the task is to compute or approximate the Pareto front, multi-objective optimization problems are considered as more difficult than single-objective problems. One should not forget that the fitness vector with respect to more than one objective contains more information that in principle can direct the search of evolutionary algorithms. Therefore, it is possible that a single-objective problem can be solved more efficiently via a generalized multi-objective model of the problem. That this is indeed the case is proved by investigating the computation of minimum spanning trees.This work was supported by the Deutsche Forschungsgemeinschaft (DFG) as part of the Collaborative Research Center Computational Intelligence (SFB 531) and by the German-Israeli Foundation (GIF) in the project Robustness Aspects of Algorithms.     

A Profile of Psychologists' Views of Critical Risk Factors for Completed Suicide in Older Adults.

The ability to accurately and reliably predict whether an older adult will commit suicide has eluded clinicians and researchers. A random national sample of psychologists who work with older adults was surveyed regarding their perception of 36 risk factors for completed suicide and indirect self-destructive behavior in older adults. This study produced a profile of psychologists' assessment and treatment practices when working with suicidal older adults. Determining what psychologists consider to be the most salient risk factors for completed suicide is important in identifying a minimum standard that clinicians should follow when assessing older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Introduction to the special series: HIV infection among drug abusers.

Drug users are particularly at risk for contracting the human immunodeficiency virus and serve as a major mechanism for spreading the virus to other sectors of the population. As a result drug abuse treatment and potential behavioral change strategies are primary public health issues. The purpose of this article is to review the contributions included in this special edition, which represent an effort to describe the most current thinking in the field with a blend of theoretical, review, and empirical articles. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Telephone booster sessions for optimizing smoking cessation for patients in rehabilitation centers.

Smokers with smoking-related diseases who are hospitalized in rehabilitation centers should be offered smoking cessation. This is the first study evaluating whether telephone booster sessions after intensive inpatient treatment are an effective strategy. The present study was conducted in 13 rehabilitation centers for somatic disorders as a prospective multicenter study with a randomized treatment-control group design. We compared abstinence rates after hospital discharge from treatment that included a group smoking cessation program with (treatment group) and without telephone booster sessions (control group). Data from 290 smokers were analyzed. After 6 and 12 months the treatment group achieved abstinence rates twice as high as those of the control group. Men profited more from telephone booster sessions than did women. Results indicated that telephone booster sessions were highly effective (even) after an inherently intensive group program during a hospital stay. Further research should focus on the special needs of women receiving telephone counseling.     

A detailed analysis of ambipolar diffusion in nanostructured metal oxide films

In this paper a transport equation is derived which describes the behaviour of the nanostructured metal oxide films in a photoelectrochemical cell. It is shown that a detailed analysis of the charge compensation mechanism necessarily leads to a transport equation with characteristics similar to but logically distinct from the pure diffusion equation. The studied phenomenon was named ambipolar diffusion in the early 1950s. It takes into account the fact that the diffusion processes of ions and electrons occur at different speeds. A weak electric field therefore couples the processes together to preserve charge neutrality. The electric field in turn affects the transport resulting in a deviation from purely diffusive behaviour. However, this has not been widely recognised in the literature for nanostructured semiconductor films until very recently. In this paper a detailed analysis is presented. It is based on the assumption that the current density is solenoidal. It is shown that application of the ambipolar diffusion model to a photoelectrochemical cell based on a nanostructured metal oxide film leads to an additional term in the transport equation, rather than only a new diffusion coefficient as in earlier work. It is also shown that the boundary conditions interact closely with the equation to form a transport model.     

Effect of progressive systemic sclerosis on antral myoelectrical activity and gastric emptying

In patients with progressive systemic sclerosis (PSS) suffering from chronic dyspepsia the stomach may be affected by this disease. The objective of this study was to investigate both antral myoelectrical activity and gastric emptying in PSS patients. Electrogastrography (EGG) was performed in 17 PSS patients (16 female, one male, median age 58 years, range 32-74 years) with chronic dyspepsia. After an overnight fast during one hour in the fasting and one hour in the fed state after ingestion of a liquid-solid test meal (370 kcal; liquid phase labeled with 0.5 mCi 99mTc-colloid) antral electrical activity was measured by one pair of electrodes sonographically placed on the skin overlying the gastric antrum. Several EGG parameters including dominant frequency (DF), percentages of DF in the normal range (2-4 cycles per minute [cpm]), bradygastria (< 2 cpm) and tachygastria (4-10 cpm), dominant frequency instability coefficient (DFIC), and postprandial to preprandial power ratio (PR) were calculated. The data were correlated to results obtained in 20 age- and gender-matched healthy subjects. In addition, the data were compared to gastric retention of the radionuclide at 60 min measured by simultaneous scintigraphy. The PSS patients did not reveal electrical disturbances. They even exhibited a significant postprandial decrease in DFIC, bradygastria, and tachygastria (ns) compared to healthy subjects. Over 50% of the PSS patients showed a delayed gastric emptying. However, EGG did not correlate to radioscintigraphy significantly. Our results reflect an absent relationship between antral myoelectrical activity in EGG and gastric emptying. Therefore, electrogastrography is unsuitable to assess gastric involvement in PSS.     

Cure of Helicobacter pylori infection: role of duration of treatment with omeprazole and amoxicillin

A case of ankylosing spondylitis with pronounced osteolysis of the 12th thoracic vertebral body as part of posttraumatic pseudoarthrosis is described. The appearance of posttraumatic osteolysis simulates a malignant lesion, and it is important to consider the diagnosis in cases of osteolytic lesions of unknown origin.     

The T Cell Repertoires from Nickel Sensitized Joint Implant Failure Patients

Nickel (Ni²⁺) is one of the most common allergens, affecting around 10–15% of the general population. As the demand for orthopedic implant surgery rises, the number of surgical revisions due to joint implant failure also increases. There is evidence that some patients develop joint failure due to an immune response to a component of the implant, and we have found that Ni²⁺ is an especially important cause. Hence, understanding the mechanisms by which Ni²⁺ allergy induces joint implant failure becomes a critical research question. The structural basis of Ni²⁺ activation of pathogenic T cells is still not clear. The purpose of this study was to characterize Ni²⁺-reactive T cell repertoires derived from the peripheral blood of joint failure patients due to Ni²⁺ sensitization using single-cell sequencing techniques. We stimulated the proliferation of Ni²⁺ -reactive T cells from two implant failure patients in vitro, and sorted them for single-cell VDJ sequencing (10× genomics). We identified 2650 productive V-J spanning pairs. Both TCR α chains and β chains were enriched. TRBV18 usage is the highest in the P7 CD4+ population (18.1%), and TRBV5-1 usage is the highest in the P7 CD8+ population (12.1%). TRBV19 and TRBV20-1 segments are present in a high percentage of both P7 and P9 sequenced T cells. Remarkably, the alpha and beta chain combination of TRAV41-TRBV18 accounts for 13.5% of the CD4+ population of P7 patient. Compared to current Ni specific T cell repertoire studies of contact dermatitis, the Vα and Vβ usages of these joint implant failure patients were different. This could be due to the different availability of self-peptides in these two different tissues. However, TRBV19 (Vβ17) was among frequently used TCR β chains, which are common in previous reports. This implies that some pathogenic T cells could be similar in Ni²⁺ hypersensitivities in skin and joints. The alignment of the TCR CDR3β sequences showed a conserved glutamic acid (Glu) that could potentially interact with Ni²⁺. The study of these Ni²⁺ specific TCRs may shed light on the molecular mechanism of T cell activation by low molecular weight chemical haptens.