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Ammonia (NH 3) represents a carbon-free hydrogen carrier that can be used as a zero-emission fuel in the maritime and heavy transport sector with hydrogen fuel cells. To use ammonia as feedstock, the hydrogen must be recovered through NH 3 decomposition into H 2 and N 2. Ammonia decomposition by a membrane-enhanced reactor would inherently produce high-purity H 2 through the membrane avoiding the need for a costly hydrogen separation/purification unit. Pd-based membrane reactors can obtain full ammonia decomposition and show significantly higher conversion than conventional reactors. However, the H 2 permeability is found to be inhibited in the presence of NH 3. A further fundamental understanding of the long-term stability and performance of the Pd-based membranes under exposure to NH 3 is therefore required. In the current work, the adsorbate-adsorbate interactions during co-adsorption, the influence the presence of NH 3 has on the hydrogen dissociation kinetics, and surface segregation effects in the presence of NH 3 and/or hydrogen on the surface of Pd and Pd 3 Ag are investigated in detail using density functional theory calculations. We find that both the hydrogen surface coverage and dissociation kinetics are hindered by the presence of NH 3 on the surface, and possible segregation of Ag towards the surface in the presence of NH 3 , which could explain the reduced hydrogen permeation in NH 3. [Display omitted] • Hydrogen and NH3 co-adsorption on Pd–Ag membranes has been investigated using density functional theory calculations. • Adsorbate-adsorbate interactions and segregation effects in the presence of NH 3 are assessed. • Both the hydrogen surface coverage and dissociation kinetics are hindered by the presence of NH 3. • The results work can be used to explain the reduced permeation performance in presence of NH 3. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.addbeh.2008.12.014 Byline: Natacha M. De Genna, Marie D. Cornelius, John E. Donovan Keywords: Pregnancy in adolescence; Smoking; Marijuana smoking; Hostility; Adolescents; Alcohol use Abstract: Teenage mothers may not 'mature out' of substance use during young adulthood, and this non-normative trajectory of use may contribute to negative outcomes for teenage mothers and their offspring. Pregnant teenagers (age range=12-18 years; 68% Black) were recruited from a prenatal clinic and interviewed about their substance use, and subsequently re-interviewed six and ten years later (n =292). Consistent with the literature, early tobacco and marijuana use were risk factors for young adult use. Other substance use, peer adolescent use and mental health indicators were more important than race and socioeconomic status (SES) in determining which teenage mothers would use tobacco, engage in binge drinking, and use marijuana as young adults. However, race and SES were significant predictors of quitting tobacco use and marijuana use by the 10-year follow-up. Depression was associated with both persistent tobacco use and marijuana use in teenage mothers. These results illustrate the long-term consequences of teenage childbearing and identify modifiable risk factors for later health risks that should be addressed among younger mothers. Author Affiliation: University of Pittsburgh and Western Psychiatric Institute and Clinic (WPIC), Program in Epidemiology Suite 138 -- Webster Hall, University of Pittsburgh School of Medicine, 4415 Fifth Avenue, Pittsburgh, PA 15213, USA

Research into the clinical factors distinguishing adolescents with heavy smoking from those with light smoking is presented. The strong link between substance-use disorders and heavy smoking among adolescents was confirmed.

The efficacy of fluoxetine persists for treating the depressive symptoms and the excessive drinking of patients with comorbid major depressive disorder and alcohol dependence. This research involved a one-year naturalistic follow-up of 31 patients who had previously participated in a three-month double-blind, placebo-controlled study of fluoxetine in depressed alcoholics. It appears that a prolonged course of up to 12 months of continuation pharmacotherapy is generally appropriate for depressed alcoholics.

[Display omitted] • CO oxidation over Pd 75% Ag 25% (100) studied by NAP-XPS. • Reversed hysteresis in CO 2 formation during heating and cooling ramps observed. • Hysteresis behaviour depends on exposure, heating rate, maximum temperature, and sample history. • Dynamic changes in Pd/Ag surface composition during cycling to 450 °C or 600 °C observed. • Relatively facile kinetics of segregation that proceeds even at ambient temperature. The dynamic changes in composition in the near-surface region of a Pd 75% Ag 25% (100) single crystal were monitored using near-ambient pressure x-ray photoelectron spectroscopy (NAP-XPS) during CO oxidation under oxygen rich conditions at a total pressure of 1.1 mbar. Six CO oxidation temperature cycles were investigated at different heating rates and maximum temperatures of 450 °C or 600 °C. It was found that the history of the bimetallic sample plays an important role, as the CO 2 formation profile varies depending on initial conditions, and previous heating rates and maximum temperatures. In terms of CO coverage effects, normal, reversed and no hysteresis behaviour were all observed. In agreement with previous modelling predictions, the NAP-XPS data confirm a dynamic segregation behaviour upon heating/cooling where the amount of Pd in the surface region decreases with increasing temperature. Nevertheless, the Pd 3d 5/2 core level relative area assessment is not fully capable of capturing all the surface dynamics inferred from the temperature dependent CO 2 formation profiles, due to the probing depth. While residing at ambient temperature in the reaction mixture, however, there is a build-up of adsorbed CO at the surface showing that CO induces segregation of Pd to the topmost surface layer under these conditions. In total, this suggests that the segregation is kinetically relatively facile during temperature cycling, and that adsorbate coverage is the main controlling factor for the surface termination. [ABSTRACT FROM AUTHOR]

• IORT for glioblastoma is delivered after excision, and is followed by adjuvant treatment with external beam radiotherapy with or without chemotherapy. • Complications are few but may include radiation necrosis, infection, hematoma, perilesional edema, and wound dehiscence. • IORT resulted in improved local control and comparable overall survival rates with the Stupp protocol. • The overall effect of IORT on GBM treatment is still inconclusive due to the small number of patients and heterogeneous reporting of data. Despite multimodality treatment, the prognosis of glioblastoma (GBM) has remained poor. Intraoperative radiation therapy (IORT) offers additional local control by directly applying a radiation source to the resection margin, where most recurrences occur. We performed a systematic review on the oncologic outcomes and toxicities of IORT for GBM in the era of modern external beam radiation therapy (EBRT) and chemotherapy with temozolamide. Four studies representing 123 patients were included. Majority (81%) were newly diagnosed, and gross total resection was reported in 13–80% of cases. IORT modalities included electrons from a linear accelerator (LINAC) and photons from a 50-kV x-ray device. Median doses were from 12.5 to 20 Gy for electron-based studies and 10–25 Gy for photon-based studies. Adjuvant treatment consisted of 46–60 Gy post-operative EBRT in electron-based studies and the Stupp protocol in photon-based studies. Complications included radiation necrosis (2.8–33%), infection, hematoma, perilesional edema, and wound dehiscence. Median time to local recurrence was 9.9–16 months and the reported overall progression-free survival was 11.2–12.2 months. Median overall survival was 13–14.2 months for the electron-based studies and 13.8–18 months for the photon-based studies. IORT resulted in improved local control and comparable overall survival rates with the Stupp protocol. Although photon-based IORT had better results than electron IORT, this may be due to improvements in other forms of adjuvant treatment rather than the IORT modality itself. The overall effect of IORT on GBM treatment is still inconclusive due to the small number of patients and heterogeneous reporting of data. [ABSTRACT FROM AUTHOR]

Trauma patients may present with nonsurvivable injuries, which could be resuscitated for future organ transplantation. Trauma surgeons face an ethical dilemma of deciding whether, when, and how to resuscitate a patient who will not directly benefit from it. As there are no established guidelines to follow, we aimed to describe resuscitation practices for organ transplantation; we hypothesized that resuscitation practices vary regionally. Over a 3-month period, we surveyed trauma surgeons practicing in Levels I and II trauma centers within a single state using an instrument to measure resuscitation attitudes and practices for organ preservation. Descriptive statistics were calculated for practice patterns. The survey response rate was 51% (31/60). Many (81%) had experience with resuscitations where the primary goal was to preserve potential for organ transplantation. Many (90%) said they encountered this dilemma at least monthly. All respondents were willing to intubate; most were willing to start vasopressors (94%) and to transfuse blood (84%) (range, 1 unit to >10 units). Of respondents, 29% would resuscitate for ≥24 hours, and 6% would perform a resuscitative thoracotomy. Respect for patients' dying process and future organ quality were the factors most frequently considered very important or important when deciding to stop or forgo resuscitation, followed closely by concerns about excessive resource use. Trauma surgeons' regional resuscitation practices vary widely for this patient population. This variation implies a lack of professional consensus regarding initiation and extent of resuscitations in this setting. These data suggest this is a common clinical challenge, which would benefit from further study to determine national variability, areas of equipoise, and features amenable to practice guidelines. [ABSTRACT FROM AUTHOR]

A study aimed to determine whether depressed alcoholics who are cocaine users would exhibit a higher rate of suicidal behaviour than depressed alcoholics who are not cocaine users. Suicidal ideation was found to be more prevalent in alcoholics who used cocaine. The results show that cocaine use is linked to an increased rate of suicidal behaviour in depressed alcoholics.

Abstract Introduction An acidic environment has been recognized to increase catabolic activities and inhibit osteoblastic deposition, and also exhibited in the pathogenesis of various bone diseases. The aim of the study was to investigate the role of systemic and local pH alteration in the pathogenesis of medication-related osteonecrosis of the jaw (MRONJ). Material and methods Initially, MRONJ was induced in 54 Sprague-Dawley rats via subcutaneous bisphosphonate injections, once a week for 8 weeks. A week prior to bisphosphonate termination, surgical intervention was performed and rats were divided into 3 groups—alkalotic, acidic and control group, wherein each received NaHCO 3 , NH 4 Cl and normal saline, respectively for 8 weeks. Upon sacrifice, blood was sent for arterial blood pH analysis and their mandibles were subjected to histomorphometric and μCT analyses. ONJ was histologically defined as necrotic bone persisting for eight weeks after surgical intervention. Results Each intervention exemplified its expected outcome wherein each group exhibited a borderline alkalotic (7.43 ± 0.05) and acidic state (7.27 ± 37), respectively (P < 0.05). Acidic group showed a higher occurrence of MRONJ (95%) compared to that of alkalotic group (60%) and control (76.9%). Histomorphometric and microstructural evaluation revealed that acidic group presented deteriorated bone architectures with significantly higher necrotic bone fraction, clusters of empty lacunae, N.Oc/B.Pm and lower B.Ar./T.Ar, BV/TV, Tb.Th (P < 0.05). Alkalotic group showed possible protective effects against ONJ versus acidic group, however these trends were not statistically significant. Conclusions An acidic milieu aggravated ONJ development in an animal model. Further investigations are needed to elucidate the exact role of acid-base balance in MRONJ pathogenesis and possible benefits of alkali supplementation for the prevention. Highlights • Acidic environment has been recognized to increase catabolic activities and be associated with the pathogenesis of various bone diseases. • The aim of the study was to investigate the role of systemic and local pH alteration in the pathogenesis of MRONJ. • Acidic group showed a higher occurrence of MRONJ and deteriorated bone architectures compared to those of alkalotic group and control. • Alkalotic group showed protective effects against ONJ and however these were not evident compared to those of acidic group versus control. • Acidic milieu aggravated MRONJ in animal model and further studies are needed to elucidate benefits of alkali supplementation for prevention. [ABSTRACT FROM AUTHOR]

Objective: To develop quality indicators (QIs) reflecting the minimum acceptable standard of rehabilitation care before and after elective total hip arthroplasty (THA) and total knee arthroplasty (TKA) for osteoarthritis (OA).Methods: Informed by high quality evidence and using a modified RAND-UCLA Delphi approach, an 18-member Canadian panel of clinicians, researchers and patients considered 81 proposed QIs (40 for THA, 42 for TKA) addressing rehabilitation before and after elective THA and TKA. Panelists rated QIs for their importance and validity on a 9-point Likert scale through two rounds of online rating interspersed with a moderated and anonymous online discussion forum. Those QIs with median ratings of ≥7 for importance and validity with no disagreement based on the inter-percentile range adjusted for symmetry were included in the final sets.Results: Fifteen panelists from seven provinces and varied practice settings completed the Delphi process. Of the 81 plus one additional QIs (total of 82), 67 (82%) were rated as both important and valid (31 for THA, 36 for TKA). For THA, 14 pre-op, six acute and eight post-acute QIs were accepted. For TKA, 16 pre-op, 10 acute and eight post-acute indicators were accepted. Two of three 'across-continuum' QIs were rated appropriate for both procedures.Conclusion: This work represents the first QIs with which to measure, report and benchmark quality of care in patients receiving rehabilitation before and after THA/TKA surgery. The QIs will be further tested for reliability and feasibility before being widely disseminated in clinical settings and used to assess care gaps. [ABSTRACT FROM AUTHOR]

ONC201/TIC10 is a first-in-class small molecule inducer of TRAIL that causes early activation of the integrated stress response. Its promising safety profile and broad-spectrum efficacy in vitro have been confirmed in Phase I/II trials in several advanced malignancies. Binding and reporter assays have shown that ONC201 is a selective antagonist of the dopamine D2-like receptors, specifically, DRD2 and DRD3. We hypothesized that ONC201's interaction with DRD2 plays a role in ONC201's anticancer effects. Using cBioportal and quantitative reversetranscription polymerase chain reaction analyses, we confirmed that DRD2 is expressed in different cancer cell types in a cell type-specific manner. On the other hand, DRD3 was generally not detectable. Overexpressing DRD2 in cells with low DRD2 levels increased ONC201-induced PARP cleavage, which was preceded and correlated with an increase in ONC201-induced CHOP mRNA expression. On the other hand, knocking out DRD2 using CRISPR/Cas9 in three cancer cell lines was not sufficient to abrogate ONC201's anticancer effects. Although ONC201's anticancer activity was not dependent on DRD2 expression in the cancer cell types tested, we assessed the cytotoxic potential of DRD2 blockade. Transient DRD2 knockdown in HCT116 cells activated the integrated stress response and reduced cell number. Pharmacological antagonism of DRD2 significantly reduced cell viability. Thus, we demonstrate in this study that disrupting dopamine receptor expression and activity can have cytotoxic effects that may at least be in part due to the activation of the integrated stress response. On the other hand, ONC201's anticancer activity goes beyond its ability to antagonize DRD2, potentially due to ONC201's ability to activate other pathways that are independent of DRD2. Nevertheless, blocking the dopamine D1-like receptor DRD5 via siRNA or the use of a pharmacological antagonist promoted ONC201-induced anticancer activity. [ABSTRACT FROM AUTHOR]

Background A hyperosmolar irrigation solution has been reported to be safe and have potential benefits for use during shoulder arthroscopy in an animal model study. In this study, the clinical effects of a hyperosmolar solution were compared with a standard isotonic solution when used for shoulder arthroscopy. Methods A prospective, double-blind, randomized controlled trial was performed to compare isotonic (273 mOsm/L) and hyperosmolar (593 mOsm/L) irrigation solutions used for arthroscopic rotator cuff repair. Primary outcomes focused on the amount of periarticular fluid retention based on net weight gain, change in shoulder girth, and pain. All patients were tracked through standard postsurgical follow-up to ensure no additional complications arose. Patients were contacted at 1 year to assess American Shoulder and Elbow Surgeon score, visual analog scale pain score, and the Single Assessment Numeric Evaluation shoulder scores Results Fifty patients (n = 25/group) were enrolled and completed the study. No statistically significant differences were noted between cohorts in demographics or surgical variables. The hyperosmolar group experienced significantly less mean weight gain (1.6 ± 0.82 kg vs. 2.25 ± 0.77 kg; P  = .005), significantly less change in shoulder girth ( P  < .05), and a significantly lower immediate postoperative visual analog scale pain score ( P  = .036). At 1 year postoperatively, the differences between groups for American Shoulder and Elbow Surgeons, visual analog scale pain, and Single Assessment Numeric Evaluation were not significant ( P  > .2). Conclusion A hyperosmolar irrigation solution provides a safe and effective way to decrease periarticular fluid retention associated with arthroscopic rotator cuff surgery without any adverse long-term effects. Use of a hyperosmolar irrigation solution for shoulder arthroscopy has potential clinical benefits to surgeons and patients. [ABSTRACT FROM AUTHOR]

Pulmonary arteriovenous malformations are often included in the differential diagnosis of common clinical presentations, including hypoxemia, hemoptysis, brain abscesses, and paradoxical stroke, as well as affecting 30% to 50% of patients with hereditary hemorrhagic telangiectasia (HHT). Various imaging studies are used in the diagnostic and screening settings, which have been reviewed by the ACR Appropriateness Criteria Vascular Imaging Panel. Pulmonary arteriovenous malformation screening in patients with HHT is commonly performed with transthoracic echocardiographic bubble study, followed by CT for positive cases. Although transthoracic echocardiographic bubble studies and radionuclide perfusion detect right-to-left shunts, they do not provide all of the information needed for treatment planning and may remain positive after embolization. Pulmonary angiography is appropriate for preintervention planning but not as an initial test. MR angiography has a potential role in younger patients with HHT who may require lifelong surveillance, despite lower spatial resolution compared with CT. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every three years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment. [ABSTRACT FROM AUTHOR]

Objective: To determine whether sequential or monophasic media is the more optimal formulation for blastocyst development and sustained implantation rates (SIR) in IVF.Design: Paired randomized controlled trials.Setting: Academic.Patient(s): Infertile couples (N = 192) with female partner ≤42 years old and normal ovarian reserve.Intervention(s): Fertilized zygotes from each patient were randomly divided into two groups: [1] cultured in sequential media and [2] cultured in monophasic medium. Sequential media consisted of Quinn's Advantage Cleavage Medium (SAGE) followed by Blast Assist (Origio). The monophasic medium used was Continuous Single Culture (Irvine Scientific). Paired ETs were accomplished by transferring the best euploid blastocyst from each media group. DNA fingerprinting was used to link outcomes.Main Outcome Measure(s): The primary outcome measure was the proportion of blastocysts suitable for clinical use. Secondary outcome measures included timing of blastulation, aneuploidy rates, and SIR. Sustained implantation rate is defined as the number fetal heart beats at 8-9 weeks of gestation, divided by the number of embryos transferred.Result(s): A total of 192 patients had their 2PN embryos (N = 2,257) randomized to each culture system. Sequential media had higher blastulation rate than monophasic medium (55.2% vs. 46.9%). No differences were found in the day of blastulation or aneuploidy rate. Of the 168 patients who had euploid blastocysts suitable for transfer, 126 completed a paired ET. Among the double ETs, there was no difference in implantation between groups.Conclusion(s): This is the first randomized controlled trial to examine paired euploid transfers of sibling zygotes cultured in sequential versus monophasic media. This study demonstrates that the usable blastocyst rate is greatest after culture in the sequential media tested in comparison with the monophasic formulation selected for study. However, no difference exists in timing of blastulation, aneuploidy, or SIR. Whether these observations are generalizable to other media systems remains to be determined.Clinical Trial Registration Number: NCT01917240. [ABSTRACT FROM AUTHOR]

We examined direct and indirect pathways between adverse environmental exposures during gestation and childhood and drinking in mid-adolescence. Mothers and their offspring ( n = 917 mother/child dyads) were followed prospectively from second trimester to a 16-year follow-up assessment. Interim assessments occurred at delivery, 6, 10, and 14 years. Adverse environmental factors included gestational exposures to alcohol, tobacco, and marijuana, exposures to childhood maltreatment and violence, maternal psychological symptoms, parenting practices, economic and home environments, and demographic characteristics of the mother and child. Indirect effects of early child behavioral characteristics including externalizing, internalizing activity, attention, and impulsivity were also examined. Polytomous logistic regression analyses were used to evaluate direct effects of adverse environmental exposures with level of adolescent drinking. Structural equation modeling (SEM) was applied to simultaneously estimate the relation between early adversity variables, childhood characteristics, and drinking level at age 16 while controlling for significant covariates. Level of drinking among the adolescent offspring was directly predicted by prenatal exposure to alcohol, less parental strictness, and exposures to maltreatment and violence during childhood. Whites and offspring with older mothers were more likely to drink at higher levels. There was a significant indirect effect between childhood exposure to violence and adolescent drinking via childhood externalizing behavior problems. All other hypothesized indirect pathways were not significant. Thus most of the early adversity measures directly predicted adolescent drinking and did not operate via childhood behavioral dysregulation characteristics. These results highlight the importance of adverse environmental exposures on pathways to adolescent drinking. [ABSTRACT FROM AUTHOR]

Objective There is a strong association between peripheral arterial disease (PAD) and future cardiovascular events. Therefore, intensive atherosclerotic risk factor reduction is recommended for people with PAD, and early detection is essential. This study assessed whether systematic pedal pulse palpation is an effective screening method for PAD in population-based screening programs. Methods As part of a randomized screening project, The Viborg Vascular Screening trial, 18,681 men (mean age, 69.3 years; range, 65-74 years) participated in a screening program, which included bilateral pulse palpation and ankle-brachial index (ABI) measurement. PAD was defined as ABI ≤0.9 or ≥1.4. Analysis was conducted on sensitivity, specificity, positive predictive value, and negative predictive value for PAD and for the number of pedal pulses. Results PAD was present in 2215 participants (12.1%). The pedal pulse palpation test was set to be positive for having PAD if one or more pulses were missing. Sensitivity was 71.7% and specificity was 72.3%. No palpable pulses were associated with a 50% chance of ABI-verified PAD or with a false finding. Four palpable pulses were associated with 5% false-negative PAD cases. Conclusions Pedal pulse palpation is was shown to be a reliable initial screening tool for PAD in population-based programs but only when four pedal pulses were present. Therefore, ABI measurement should routinely be measured in patients with fewer than four palpable pedal pulses so cardiovascular preventive actions can be initiated if PAD is confirmed. [ABSTRACT FROM AUTHOR]

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The central and eastern Mediterranean is a receptor area for persistent organic pollutants (POPs) emitted in western, central and eastern Europe, particularly during summer. Atmospheric concentrations of PCBs, DDXs, PBDEs, penta- and hexachlorobenzene were measured during a ship-borne survey in the summer of 2010. The concentration of PCBs (sum of 7 congeners) was 3.61 (2.08–7.72) pg m −3 , of which 6.7% was associated with the particulate phase. The mean concentration of DDT isomers and their metabolites, DDE and DDD, was 2.60 (0.46–7.60) pg m −3 (particulate mass fraction θ = 0.097), of penta- and hexachlorobenzene 0.22 (<0.39–2.80) pg m −3 and 6.29 (2.48–24.16) pg m −3 , respectively, and of PBDEs (sum of 8 congeners) 7.31 (2.80–19.89) pg m −3 . The air masses studied had been transported mostly across central Europe, some crossing western Europe. The observed changes of PCB congener patterns along transport routes are in agreement with the perception that the reaction with the OH radical is dominating PCB atmospheric lifetime, and indicate an overestimation of the second order gas-phase reaction rate coefficient of PCB153 with OH by structure-activity relationship. [ABSTRACT FROM AUTHOR]