Wear mechanisms description in nanoscale by SEM/TEM of multilayer Zr/ZrN coatings in dependence on phases ratio.

As a result of loading with an external force during the wear process, coating deforms uniformly. After a certain limit load is exceeded, coating deformation is localised through the formation of the so-called shear bands. It has been showed experimentally the process of shear bands formation. The microstructural characterisation before and after the mechanical tests was performed using scanning and transmission electron microscopy (SEM and TEM) on cross-sections of the samples. The analysis indicated that in the case of multilayer coatings where the ratio of the metallic to the ceramic phase is 1:1, the shear bands are formed at an angle of 45°. With a greater proportion of the ceramic phase to metallic (ratio 1:2), the shear band changed the shear angle from ∼45° to ∼90°. Mechanical in situ tests were carried out in the chambers of SEM and TEM. The scratch tests in the SEM were done with the simultaneous observation of the phenomena occurring on the surface of the tested materials showed that at a scratch force of 0.04 N, the additional outer a-C:H layer was damaged, which was shown in the form of a fault in the force-displacement diagram, and in the form of splits visible in the SEM image. However, the application of this additional layer had a positive effect on the wear mechanism of the entire coating structure. The test also indicated that in the case of coatings with phases ratio 1:2 and 1:4 (metallic to ceramic), the characteristics of the brittle material were demonstrated, unlike the coating with a 1:1 phase ratio, where plastic properties predominated. However, for the 1:2 phase ratio coating, the chip was more ductile than for the chip formed when testing a 1:4 phase ratio coating. For in situ mechanical testing in the TEM, a straining holder was used. The test showed that the shear band angle for a 1:1 ratio coating has changed from 45° to 90° due to the different direction of force interaction.

Wear mechanisms of the biotribological nanocomposite a-C : H coatings implanted by metallic nanoparticles.

Recently, to reduce the residual stress and increase the mechanical properties of a-C:H coatings, metallic nanoparticles have been implanted into their structure. In the present work, to improve the properties of the coating, metallic nanoparticles, including Cu, Nb, Ta, Zr, AgPt and Ag, were inserted into the a-C:H structure. The applied biological and mechanical analysis allowed the optimal biotribological parameters to be indicated for the potential application as protective coatings for metallic medical tools. Wear mechanisms operating at the small length of the designed biotribological coating, such as a-C:H implanted by Zr nanoparticles, were studied by means of transmission electron microscopy (TEM). The TEM analysis confirmed very good coating adhesion to the metallic substrate.

Microstructure characterization of advanced protective Cr/CrN+a-C:H/a-C:H:Cr multilayer coatings on carbon fibre composite (CFC).

Studies of advanced protective chromium-based coatings on the carbon fibre composite (CFC) were performed. Multidisciplinary examinations were carried out comprising: microstructure transmission electron microscopy (TEM, HREM) studies, micromechanical analysis and wear resistance. Coatings were prepared using a magnetron sputtering technique with application of high-purity chromium and carbon (graphite) targets deposited on the CFC substrate. Selection of the CFC for surface modification in respect to irregularities on the surface making the CFC surface more smooth was performed. Deposited coatings consisted of two parts. The inner part was responsible for the residual stress compensation and cracking initiation as well as resistance at elevated temperatures occurring namely during surgical tools sterilization process. The outer part was responsible for wear resistance properties and biocompatibility. Experimental studies revealed that irregularities on the substrate surface had a negative influence on the crystallites growth direction. Chromium implanted into the a-C:H structure reacted with carbon forming the cubic nanocrystal chromium carbides of the Cr23 C6 type. The cracking was initiated at the coating/substrate interface and the energy of brittle cracking was reduced because of the plastic deformation at each Cr interlayer interface. The wear mechanism and cracking process was described in micro- and nanoscale by means of transmission electron microscope studies. Examined materials of coated CFC type would find applications in advanced surgical tools.

Cannabis use and first-episode psychosis: relationship with manic and psychotic symptoms, and with age at presentation.

BACKGROUND: Cannabis use has been reported to be associated with an earlier onset of symptoms in patients with first-episode psychosis, and a worse outcome in those who continue to take cannabis. In general, studies have concentrated on symptoms of psychosis rather than mania. In this study, using a longitudinal design in a large naturalistic cohort of patients with first-episode psychosis, we investigated the relationship between cannabis use, age of presentation to services, daily functioning, and positive, negative and manic symptoms. METHOD: Clinical data on 502 patients with first-episode psychosis were collected using the MiData audit database from seven London-based Early Intervention in psychosis teams. Individuals were assessed at two time points--at entry to the service and after 1 year. On each occasion, the Positive and Negative Syndrome Scale, Young Mania Rating Scale and Global Assessment of Functioning Scale disability subscale were rated. At both time points, the use of cannabis and other drugs of abuse in the 6 months preceding each assessment was recorded. RESULTS: Level of cannabis use was associated with a younger age at presentation, and manic symptoms and conceptual disorganization, but not with delusions, hallucinations, negative symptoms or daily functioning. Cannabis users who reduced or stopped their use following contact with services had the greatest improvement in symptoms at 1 year compared with continued users and non-users. Continued users remained more symptomatic than non-users at follow-up. CONCLUSIONS: Effective interventions for reducing cannabis use may yield significant health benefits for patients with first-episode psychosis.

Arthroplasty Rates Not Increasing in Young Patients With Rheumatoid Arthritis: A National Database Review, 2005 Versus 2014.

BACKGROUND: For 20 years, authors have predicted an expansion in total knee arthroplasty (TKA) and total hip arthroplasty (THA) utilization. Over this same period, the introduction of biological disease-modifying antirheumatic drugs has dramatically altered the treatment of rheumatoid arthritis (RA) with hopes of preventing articular damage and obviating the need for prosthetic replacement. The goal of our investigation was to evaluate TKA and THA utilization in young patients with RA (<65 years) in 2005 vs 2014 compared to patients with osteoarthritis (OA). METHODS: Using relevant International Classification of Disease Ninth Revision (ICD-9) and Current Procedural Terminology codes, the Truven MarketScan Database (over 46 million enrollees) was queried to determine THA and TKA incidence rates for RA and OA patients aged <65 years during the final decade of ICD-9 use. Patients with potentially confounding ICD-9 codes were excluded to limit coding variation. Statistical analysis consisted of student t-tests, Pearson's chi-square tests, and Breslow-Day tests. RESULTS: For patients with OA, TKAs increased substantially from 0.07% in 2005 to 0.1% in 2014 (+42.9% change, P < .001). Similarly for patients with OA, THAs increased from 0.04% to 0.06% over the same time period (+66.0% change, P < .001). For young patients with RA, the rate of TKA remained relatively stable-1.06% in 2005 to 1.04% in 2014 (-1.7% change, P = .65)-as did THA-0.44% to 0.48% (+9.0% change, P = .14). CONCLUSIONS: Dramatic increases in THA and TKA rates for OA patients aged <65 years were indeed observed from 2005 to 2014. This trend, however, was not seen in the RA population where TKA and THA rates remained unchanged.

Incidence and risk factors of reoperation in patients with adjacent segment disease: A meta-analysis.

STUDY DESIGN: This was a systematic review of the literature and meta-analysis. OBJECTIVE: The objective of this study was to evaluate the current literature regarding the risk factors contributing to reoperation due to adjacent segment disease (ASD). SUMMARY OF BACKGROUND DATA: ASD is a broad term referring to a variety of complications which might require reoperation. Revision spine surgery is known to be associated with poor clinical outcomes and high rate of complications. Unplanned reoperation has been suggested as a quality marker for the hospitals. MATERIALS AND METHODS: An electronic search was conducted using PubMed. A total of 2467 articles were reviewed. Of these, 55 studies met our inclusion criteria and included an aggregate of 1940 patients. Data were collected pertaining to risk factors including age, sex, fusion length, lumbar lordosis, body mass index, pelvic incidence, sacral slope, pelvis tilt, initial pathology, type of fusion procedure, floating versus sacral or pelvic fusion, presence of preoperative facet or disc degeneration at the junctional segment, and sagittal orientation of the facets at the junctional segment. Analysis of the data was performed using Comprehensive Meta-Analysis software (Biostat, Inc.). RESULTS: The overall pooled incidence rate of reoperation due to ASD from all included studies was 0.08 (confidence interval: 0.065-0.098). Meta-regression analysis demonstrated no significant interaction between age and reoperation rate (P = 0.48). A comparison of the event rates between males and females demonstrated no significant difference between male and female reoperation rates (P = 0.58). There was a significantly higher rate of ASD in patients with longer fusion constructs (P = 0.0001). CONCLUSIONS: We found that 8% of patients in our included studies required reoperation due to ASD. Our analysis also revealed that longer fusion constructs correlated with a higher rate of subsequent revision surgery. Therefore, the surgeon should limit the number of fusion levels if possible to reduce the risk of future reoperation due to ASD. LEVEL OF EVIDENCE: IV.

Α 10-gigawatt attosecond source for non-linear XUV optics and XUV-pump-XUV-probe studies.

The quantum mechanical motion of electrons and nuclei in systems spatially confined to the molecular dimensions occurs on the sub-femtosecond to the femtosecond timescales respectively. Consequently, the study of ultrafast electronic and, in specific cases, nuclear dynamics requires the availability of light pulses with attosecond (asec) duration and of sufficient intensity to induce two-photon processes, essential for probing the intrinsic system dynamics. The majority of atoms, molecules and solids absorb in the extreme-ultraviolet (XUV) spectral region, in which the synthesis of the required attosecond pulses is feasible. Therefore, the XUV spectral region optimally serves the study of such ultrafast phenomena. Here, we present a detailed review of the first 10-GW class XUV attosecond source based on laser driven high harmonic generation in rare gases. The pulse energy of this source largely exceeds other laser driven attosecond sources and is comparable to the pulse energy of femtosecond Free-Electron-Laser (FEL) XUV sources. The measured pulse duration in the attosecond pulse train is 650 ± 80 asec. The uniqueness of the combined high intensity and short pulse duration of the source is evidenced in non-linear XUV-optics experiments. It further advances the implementation of XUV-pump-XUV-probe experiments and enables the investigation of strong field effects in the XUV spectral region.

Psychological responses after abortion.

A review of methodologically sound studies of the psychological responses of U.S. women after they obtained legal, nonrestrictive abortions indicates that distress is generally greatest before the abortion and that the incidence of severe negative responses is low. Factors associated with increased risk of negative response are consistent with those reported in research on other stressful life events.

The Effect of Patient Weight and Provider Training and Experience on Dosing of Rocuronium.

Introduction. Maintenance dosing of neuromuscular blocking agents is complex and varies with patient, procedure, and clinical situation. With this in mind, we sought to identify factors impacting the maintenance dosing of neuromuscular blockers as a step toward identifying best practice with respect to minimizing residual neuromuscular blockade. Methods. Cases utilizing rocuronium from July 1, 2010, to June 30, 2014, at the sponsoring institution were analyzed. Using a mixed model to account for repeated measures, patients were analyzed by dose and weight category as defined by the World Health Organization (eight categories ranging from very severely underweight to very severely obese) as well as by the administering provider's level of experience. Results. The study included 12,671 patients with a mean age of 49.7 (SD 16.7). Increasing weight category and higher levels of provider experience were associated with higher doses for rocuronium. There were no differences in initial dose or in frequency of maintenance dosing by weight category after controlling for case length. Discussion. The two dosing patterns identified, higher doses for overweight patients and higher doses administered by experienced providers, are modifiable factors that could enhance patient safety.

Use of Whole Genome Sequencing and Patient Interviews To Link a Case of Sporadic Listeriosis to Consumption of Prepackaged Lettuce.

We report on a case of listeriosis in a patient who probably consumed a prepackaged romaine lettuce-containing product recalled for Listeria monocytogenes contamination. Although definitive epidemiological information demonstrating exposure to the specific recalled product was lacking, the patient reported consumption of a prepackaged romaine lettuce-containing product of either the recalled brand or a different brand. A multinational investigation found that patient and food isolates from the recalled product were indistinguishable by pulsed-field gel electrophoresis and were highly related by whole genome sequencing, differing by four alleles by whole genome multilocus sequence typing and by five high-quality single nucleotide polymorphisms, suggesting a common source. To our knowledge, this is the first time prepackaged lettuce has been identified as a likely source for listeriosis. This investigation highlights the power of whole genome sequencing, as well as the continued need for timely and thorough epidemiological exposure data to identify sources of foodborne infections.

Psychological responses of women after first-trimester abortion.

BACKGROUND: Controversy exists over psychological risks associated with abortion. The objectives of this study were to examine women's emotions, evaluations, and mental health after an abortion, as well as changes over time in these responses and their predictors. METHODS: Women arriving at 1 of 3 sites for an abortion of a first-trimester unintended pregnancy were randomly approached to participate in a longitudinal study with 4 assessments-1 hour before the abortion, and 1 hour, 1 month, and 2 years after the abortion. Eight hundred eighty-two (85%) of 1043 eligible women approached agreed; 442 (50%) of 882 were followed for 2 years. Preabortion and postabortion depression and self-esteem, postabortion emotions, decision satisfaction, perceived harm and benefit, and posttraumatic stress disorder were assessed. Demographic variables and prior mental health were examined as predictors of postabortion psychological responses. RESULTS: Two years postabortion, 301 (72%) of 418 women were satisfied with their decision; 306 (69%) of 441 said they would have the abortion again; 315 (72%) of 440 reported more benefit than harm from their abortion; and 308 (80%) of 386 were not depressed. Six (1%) of 442 reported posttraumatic stress disorder. Depression decreased and self-esteem increased from preabortion to postabortion, but negative emotions increased and decision satisfaction decreased over time. Prepregnancy history of depression was a risk factor for depression, lower self-esteem, and more negative abortion-specific outcomes 2 years postabortion. Younger age and having more children preabortion also predicted more negative abortion evaluations. CONCLUSIONS: Most women do not experience psychological problems or regret their abortion 2 years postabortion, but some do. Those who do tend to be women with a prior history of depression.

APOE epsilon4 genotype is associated with an earlier onset of chronic temporal lobe epilepsy.

The authors analyzed the association between APOE epsilon4 genotype and clinical and MRI findings in 43 refractory temporal lobe epilepsy patients. The distribution of the alleles were normal. Ten patients (23%) had an APOE epsilon 4 allele and had an earlier onset of habitual seizures (with epsilon4 5 +/- 5 years; without epsilon4 15 +/- 10 years). Quantitative MRI findings were not influenced by the APOE epsilon4 genotype. APOE epsilon4 may shorten the latency between an initial injury and seizure onset.

Prophylactic use of tetracycline for first trimester abortions.

Because the efficacy of prophylactic antibiotic therapy has yet to be established and because numerous variables often hamper studies of such therapy, the results of prophylactic antibiotic therapy were studied in a homogeneous gynecologic population. The patients were 4000 women undergoing first trimester abortions. The surgical procedure, the gynecologists' skill, and the hospital environment were relatively uniform, as was the patient age range. Two groups of 1000 patients each received tetracycline; the other 2000 patients served as controls. The complications associated with abortion were then analyzed in those receiving tetracycline and in the 2000 controls. Complications were less frequent among patients receiving tetracycline. This finding supports the argument of those who favor the prophylactic use of antibiotics in the management of various high-risk surgical problems.

PIP: An evaluative study of the prophylactic use of tetracycline in 1st-trimester abortions is presented. 2 groups of 1000 patients received 1.5 gm of tetracycline hydrochloride, orally, 2-3 hours before the abortion procedure, followed by 500 mg every 6 hours for 4 days. 2 groups of 1000 patients served as controls. The patient population and operative conditions were relatively uniform. The total complication rates for the antibiotic groups were 3.4% and 2.9%, and 9.1% and 8.8% for the controls. 118 of the control group patients experienced major complications compared with 45 patients in the antibiotic group. The results tend to support the arguments for the use of antibiotics in managing high-risk surgical procedures.

Self-blame, self-efficacy, and adjustment to abortion.

The causal impact of attributions and coping self-efficacy on adjustment to abortion was examined. Two hundred and eighty-three women were randomly assigned prior to their abortion to 1 of 3 counseling interventions: 1 designed to alter attributions for unwanted pregnancy (ATT-INT), 1 designed to raise coping expectations (EXP-INT), or a control (standard counseling) group. Depression, mood, anticipated consequences, and physical complaints were assessed postabortion. Women in the ATT-INT or EXP-INT group were better adjusted immediately postabortion than women in the control group. The EXP-INT group was also less depressed than the ATT-INT group. Three individual difference factors were also related to better adjustment: high coping self-efficacy, low self-character blame, and low other-blame. Self-efficacy also predicted adjustment 3 weeks postabortion. Implications for theories of adjustment to major life events, therapeutic interventions to assist coping with such events, and public policy on abortion are discussed.

Attributions, expectations, and coping with abortion.

We examined cognitive predictors of coping with a negative life event. Women undergoing first-trimester abortion were, before the procedure, surveyed regarding their attributions for their pregnancy, expectations for coping, the meaningfulness of the pregnancy, and the degree to which the pregnancy was intended. After the abortion and again at a follow-up visit, we assessed affective state, physical complaints, anticipated negative consequences, and depression. As predicted, women who blamed their pregnancy on their character coped less well than low self-character blamers, but contrary to predictions, self-behavior blame was unrelated to coping. Women who had high coping expectations before the abortion coped much better than those with low coping expectations. Women who found their pregnancy highly meaningful, however, coped worse immediately after the abortion than did women who found their pregnancy less meaningful. Intentionality of the pregnancy was related to depression three weeks after the abortion, and women accompanied by their partner to the abortion clinic coped less well immediately after the abortion than women unaccompanied by their partner.

PIP: This paper examines cognitive predictors of coping with a negative life event. Women undergoing 1st-trimester abortion were, before the procedure, surveyed regarding their attributions for their pregnancy, expectations for coping, the meaningfulness of the pregnancy, and the degree to which the pregnancy was intended. After the abortion, and again at a follow-up visit, affective state, physical complaints, anticipated negative consequences, and depression were assessed. As predicted, women who blamed their pregnancy on their character coped less well than low self-character blamers, but contrary to predictions, self-behavior blame was unrelated to coping. Subjects were 247 women who underwent vacuum aspiration at a free-standing, private abortion clinic in a large metropolitan area in New York State. 65% blamed no other person for their pregnancy; 43% blamed no aspect of their character; 34% blamed no aspect of their situation, and 21% blamed no aspect of chance. The items within a given attributional category tended to be blamed in a somewhat mutually exclusive manner. High situation blamers were significantly more depressed than low situation blamers; those who blamed others anticipated more severe negative consequences than did those who did not blame others; and high chance blamers tended to experience a worse affective state than low chance blamers. External blame was generally unrelated to coping in this study. Further research is clearly needed on the consequences of self-blame for coping and depression, with attention to the characteristics of the particular life event being experienced. The beneficial aspects of high coping expectations persisted 3 weeks after the abortion, even when immediate coping espectations were statistically controlled. Self-efficacy expectations are important factors in both the initiation and persistence of coping behaviors. Partner presence or absence at the abortion clinic had a significant impact on immediate coping responses. Surprisinly, women accompanied by their partners were significantly more depressed and reported more physical complaints than did women unaccompained by their partners. Women accompained by their partner were younger and had expected to cope less well with the abortion than those unaccompained by their partners.

Abortion as stigma: cognitive and emotional implications of concealment.

This study examined the stigma of abortion and psychological implications of concealment among 442 women followed for 2 years from the day of their abortion. As predicted, women who felt stigmatized by abortion were more likely to feel a need to keep it a secret from family and friends. Secrecy was related positively to suppressing thoughts of the abortion and negatively to disclosing abortion-related emotions to others. Greater thought suppression was associated with experiencing more intrusive thoughts of the abortion. Both suppression and intrusive thoughts, in turn, were positively related to increases in psychological distress over time. Emotional disclosure moderated the association between intrusive thoughts and distress. Disclosure was associated with decreases in distress among women experiencing intrusive thoughts of their abortion, but was unrelated to distress among women not experiencing intrusive thoughts.

Mental models of attachment and coping with abortion.

This study explored the relationships between mental models of attachment and adjustment to abortion in 408 women undergoing a 1st-trimester abortion at a large free-standing abortion clinic. As expected, mental models of attachment were related to postabortion distress and positive well-being. These relationships were mediated by feelings of self-efficacy for coping with abortion, perceived support from a woman's male partner, and perceived conflict from this same source. Model of self and model of others interacted only in predicting perceived conflict and positive well-being. Model of self was more strongly related to the mediator and outcome variables than was model of others. The effects of model of self, however, were largely a reflection of the overlap between model of self and self-esteem.

PIP: The relationship between mental models of attachment and adjustment to induced abortion was explored in 408 women undergoing first-trimester pregnancy termination at an abortion clinic in Buffalo, New York (US), in 1993. It was hypothesized that mental models would affect how supportive or conflictive a woman perceived her male partner to be and her self-efficacy in coping with the stress of abortion. It was further postulated that social support, social conflict, and self-efficacy would function as mediators of the associations among mental models and postabortion adjustment. 40% of respondents characterized their attachment style as secure; another 32% described themselves as fearful, 9% as preoccupied, and 19% as dismissing. As expected, women with secure attachment styles perceived higher levels of social support and lower levels of conflict from their male partners than other women and had higher self-esteem. The more positive a woman's model of self, the less distress she reported in the immediate postabortion period. A positive model of self also had a promotive effect on self-efficacy for coping. The effects of model of self were largely a reflection, however, of the overlap between model of self and self-esteem. The combination of self-esteem, the attachment variables, and the mediator variables accounted for 24% of the variance in postabortion distress and 65% of the variance in postabortion positive well-being. Further research is needed to clarify the differential effects of general versus specific mental models of attachment on a wide variety of processes.

The stigma of overweight: affective consequences of attributional ambiguity.

Attributing negative outcomes to prejudice and discrimination may protect the mood and self-esteem of some stigmatized groups. Thus, the overweight may be low in self-esteem because they blame their weight, but not the attitudes of others, for negative outcomes based on their weight. In an experiment, 27 overweight and 31 normal weight college women received either positive or negative social feedback from a male evaluator. Relative to other groups, overweight women who received negative feedback attributed the feedback to their weight but did not blame the evaluator for his reaction. This attributional pattern resulted in more negative mood for these overweight women in comparison with other groups. Dimensions of stigma that may account for differences in the tendency to attribute negative outcomes to prejudice, and implications of these findings for weight loss programs and psychotherapy for the overweight, are discussed.

Gender patterns in social touch: the impact of setting and age.

This study examined the impact of age of participants and the setting in which touch occurred on gender patterns in 799 instances of observed intentional touch. Gender asymmetry, a pattern in which men are more likely to touch women than vice versa, was observed when touch between adults was examined but not when touch involving children was examined. Adult touch interactions occurring in public, nonintimate settings showed gender asymmetry, but adult touch interactions occurring in greeting or leave-taking settings did not. Cross-sex touch was more prevalent among adults, whereas same-sex touch was more prevalent when a child was involved. Implications for theoretical perspectives on gender and touch are discussed.

Overworked and underpaid: on the nature of gender differences in personal entitlement.

This research investigated gender differences in feelings of personal entitlement with respect to monetary payment for work performed. Two experiments were conducted to test the hypothesis that women's internal standards of fair pay for their work are lower than men's and to examine possible causes of this difference. In Experiment 1, men and women were asked to pay themselves in a private situation what they thought was fair pay for a fixed amount of work. Social comparison information was varied. As predicted, women paid themselves less money than men in the absence, but not the presence, of social comparison information. In Experiment 2, men and women were asked to do as much work as they thought was fair for a fixed, prepaid, amount of money. Subjects believed that their work was either monitored or unmonitored. Women worked significantly longer, did more work, and did more correct work than men in both public and private work settings. Furthermore, women, but not men, worked longer when they believed their work was monitored than when they believed it was unmonitored. Possible explanations for these gender differences are discussed.