Brazil's natural grasslands under attack Overbeck, Gerhard E; Toma, Tiago S P; da Silveira-Filho, Ricardo R ...
Science (American Association for the Advancement of Science),
2024-Apr-12, 2024-04-12, 20240412, Letnik:
384, Številka:
6692
Journal Article
Regardless the increasingly incorporation of composite materials on vehicle components, high pressure die casting still remains one of the most useful manufacturing techniques to obtain automotive ...parts with a complex shape in a cost effective way. It is well known that automotive industry requires high production cadence as well as high products quality. Thus, systematic approaches are permanently being done leading to optimize all the production and management aspects.
The aluminum alloys commonly used in automotive parts such as fuel pumps bodies, throttle bodies, EGR valves, support brackets and so on usually contain Silicon which presents high abrasively. The aluminum flow at high temperature and high speed into the mold induces severe wear, sometimes due to a combination of abrasion and erosion effects.
In this study, two molds with typical severe wear problems were selected and the wear mechanisms involved were deeply studied. After that, a careful selection of the best coating for this purpose was done and some of the most critical parts of the mold were coated in order to test possible effective advantages of the coating application, analyzing the wear resistance behavior and wear mechanisms involved. In parallel, tribological tests were also carried out in order to study if a correlation between laboratory and industrial tests can be drawn. Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy were intensively used to characterize the coatings and the wear mechanisms observed. Laboratory tribological tests have involved ball scattering and block-on-ring tests, trying to impose low and medium loads on the contact, respectively. Promising results were obtained allowing conclude that certain coatings present a better behavior than other ones in this field of application.
•High-pressure die casting molds require high maintenance due to its hard work.•Coatings have been already applied in this kind of tool subjected to high temperature.•Two different TiAlN were tested in order to overcome molds cavity wear.•Ti40Al60N showed better performance than Ti50Al50N in laboratory tests.•Industrial tests confirmed the best performance of Ti40Al60N used in core pins of molds.
Previous studies have shown that repetitive transcranial magnetic stimulation (rTMS) to the dorsolateral prefrontal cortex may serve as a potential treatment for cocaine use disorder (CUD), which ...remains a public health problem that is refractory to treatment. The goal of this pilot study was to investigate the effect of rTMS on cocaine self-administration in the laboratory. In the self-administration sessions, CUD participants chose between cocaine and an alternative reinforcer (money) in order to directly measure cocaine-seeking behavior. The rTMS was delivered with the H7 coil, which provides stimulation to the medial prefrontal cortex (mPFC) and anterior cingulate cortex (ACC). These brain regions were targeted based on previous imaging studies demonstrating alterations in their activation and connectivity in CUD.
Volunteers with CUD were admitted to an inpatient unit for the entire study and assigned to one of three rTMS groups: high frequency (10 Hz), low frequency (1 Hz), and sham. Six participants were included in each group and the rTMS was delivered on weekdays for 3 weeks. The cocaine self-administration sessions were performed at three time points: at baseline (pre-TMS, session 1), after 4 days of rTMS (session 2), and after 13 days of rTMS (session 3). During each self-administration session, the outcome measure was the number of choices for cocaine.
The results showed a significant group by time effect (
= 0.02), where the choices for cocaine decreased between sessions 2 and 3 in the high frequency group. There was no effect of rTMS on cocaine self-administration in the low frequency or sham groups.
Taken in the context of the existing literature, these results contribute to the data showing that high frequency rTMS to the prefrontal cortex may serve as a potential treatment for CUD.
Bovine pericardium (BP) has been used as a biomaterial for several decades in many medical applications particularly due to its mechanical properties and the high collagen content. In the acellular ...form it favors faster tissue repair, providing a three-dimensional support for cellular and vascular events observed during tissue repair and due, to a low elastin content, may favor its use as a breast implant cover, resulting in a low possibility of contracture of the biomaterial, preventing the appearance of irregularities during the reconstruction process. Thus, the aim of this study was to evaluate, histomorphologically, the behavior of acellularized bovine pericardium (ABP) as a mammary implant cover in rats. For this purpose, 16 animals were divided into two groups, with eight animals at each biological point: 7 and 15 days after surgery. Of the 16 animals, 32 specimens were obtained: 16 in the experimental group (EG) and 16 in the control group (CG). Throughout this study, none of the studied groups had postoperative complications. Results: The histomorphological results showed, in the two biological points, both in the EG and in the CG, chronic inflammatory infiltrate, leukocyte fibrin exudate, formation of granulation tissue and deposition of collagen fibers, more evident in the EG, regressive along the biological points. At 15 days, the implanted ABP showed initial biointegration with the fibrous capsule and surrounding tissues of the recipient bed. Conclusion: These results indicate that the due to the observed favorable tissue response ABP may be of potential use as a breast implant cover.
To compare the prevalence of physical morbidities between older aged patients with bipolar disorder (OABD) and non-psychiatric comparisons (NC), and to analyze sex differences in prevalence.
OABD was ...defined as bipolar disorder among adults aged ≥50 years. Outcomes analyzed were the prevalence of diseases affecting the cardiovascular, respiratory, gastrointestinal, genitourinary, renal, musculoskeletal, and endocrine systems. The analysis used cross-sectional data of OABD participants (n = 878; mean age 60.9 ± 8.0 years, n = 496 (56%) women) from the collaborative Global Aging & Geriatric Experiments in Bipolar Disorder (GAGE-BD) dataset and NC participants recruited at the same sites (n = 355; mean age 64.4 ± 9.7 years, n = 215 (61%) women).
After controlling for sex, age, education, and smoking history, the OABD group had more cardiovascular (odds ratio 95% confidence interval: 2.12 1.38–3.30), renal (5.97 1.31–43.16), musculoskeletal (2.09 1.30–3.43) and endocrine (1.90 1.20–3.05) diseases than NC. Women with OABD had more gastrointestinal (1.56 0.99–2.49), genitourinary (1.72 1.02–2.92), musculoskeletal (2.64 1.66–4.37) and endocrine (1.71 1.08–2.73) comorbidities than men with OABD, when age, education, smoking history, and study site were controlled.
This replication GAGE-BD study confirms previous findings indicating that OABD present more physical morbidities than matched comparison participants, and that this health burden is significantly greater among women.
Nickel hydroxide nanoparticles with enhanced electrocatalytic activity and stability in the alpha phase were prepared by incorporation of 20 atom% of Ce(III) ions, that were shown to be oxidized to ...the catalytic active Ce(IV) species in the mixed hydroxide/oxide nanomaterial. Alpha-NiCe is constituted by smaller nanoparticles as compared with pure nickel hydroxide and can interact with prednisone, a widely prescribed medicine that is controlled by the International Anti-Doping Agency because of its use as anabolic agent. This compound is more or less easily hydroxilated by oxygen and then oxidized to the respective keto species, that was shown to be oxidized further by the modified electrodes upon loss of the alkyl side chain. Thus, a sensitive prednisone sensor was demonstrated exploring the electrocatalytic oxidation reaction instead of the reduction of prednisone to prednisolone, as previously reported in the literature. Sensitivity as high as 3.9×10−2Amol−1L/cm2 and limit of detection as low as 8.4×10−9molL−1 were achieved using flow injection analyses.
Sublingual buprenorphine-naloxone and extended-release injection naltrexone are effective treatments, with distinct mechanisms, for opioid use disorder. The authors examined whether patients' ...demographic and clinical characteristics were associated with better response to one medication or the other.
In a multisite 24-week randomized comparative-effectiveness trial of assignment to buprenorphine-naloxone (N=287) compared with extended-release naltrexone (N=283) comprising inpatients planning to initiate medication treatment for opioid use disorder, 50 demographic and clinical characteristics were examined as moderators of the effect of medication assignment on relapse to regular opioid use and failure to initiate medication. Moderator-by-medication interactions were estimated using logistic regression with correction for multiple testing.
In the intent-to-treat sample, patients who reported being homeless had a lower relapse rate if they were assigned to receive extended-release naltrexone (51.6%) compared with buprenorphine-naloxone (70.4%) (odds ratio=0.45, 95% CI=0.22, 0.90); patients who were not homeless had a higher relapse rate if they were assigned to extended-release naltrexone (70.9%) compared with buprenorphine-naloxone (53.1%) (odds ratio=2.15, 95% CI=1.44, 3.21). In the subsample of patients who initiated medication, the interaction was not significant, with a similar pattern of lower relapse with extended-release naltrexone (41.4%) compared with buprenorphine (68.6%) among homeless patients (odds ratio=0.32, 95% CI=0.15, 0.68) but less difference among those not homeless (extended-release naltrexone, 57.2%; buprenorphine, 52.0%; odds ratio=1.24, 95% CI=0.80, 1.90). For failure to initiate medication, moderators were stated preference for medication (failure was less likely if the patient was assigned to the medication preferred), parole and probation status (fewer failures with extended-release naltrexone for those on parole or probation), and presence of pain and timing of randomization (more failure with extended-release naltrexone for patients endorsing moderate to severe pain and randomized early while still undergoing medically managed withdrawal).
Among patients with opioid use disorder admitted to inpatient treatment, homelessness, parole and probation status, medication preference, and factors likely to influence tolerability of medication initiation may be important in matching patients to buprenorphine or extended-release naltrexone.
Opioid use disorder continues to be a significant problem in the United States and worldwide. Three medications-methadone, buprenorphine, and extended-release injectable naltrexone,- are efficacious ...for treating opioid use disorder (OUD). However, the utility of these medications is limited, in part due to poor rates of retention in treatment. In addition, minimum recovery milestones and other factors that influence when and whether individuals can safely discontinue medications are unknown. The National Drug Abuse Treatment Clinical Trials Network (CTN) study "Optimizing Retention, Duration, and Discontinuation Strategies for Opioid Use Disorder Pharmacotherapy" (RDD; CTN-0100) will be among the largest clinical trials on treatment of OUD yet conducted, consisting of two phases, the Retention phase, and the Duration-Discontinuation phase. The Retention phase, open to patients initiating treatment, will test different doses and formulations of buprenorphine (standard dose sublingual, high dose sublingual, or extended-release injection), and a digital therapeutic app delivering contingency management and cognitive behavioral counseling on the primary outcome of retention in treatment. The Discontinuation phase, open to patients in stable remission from OUD and choosing to discontinue medication (including participants from the Retention phase or from the population of patients treated at the clinical site, referred by an outside prescriber or self-referred) will study different tapering strategies for buprenorphine (sublingual taper vs taper with injection buprenorphine), and a digital therapeutic app which provides resources to promote recovery, on the primary outcome of relapse-free discontinuation of medication. This paper describes how the RDD trial derives from two decades of research in the CTN. Initial trials (CTN-0001; CTN-0002; CTN-0003) focused on opioid detoxification, showing buprenorphine-naloxone was effective for detoxification, but that acute detoxification did not appear to be an effective treatment strategy. Trials on comparative effectiveness of medications for opioid use disorder (MOUD) (CTN-0027; CTN-0030; and CTN-0051) highlighted the problem of dropout from treatment and few trials defined retention on MOUD as the primary outcome. Long-term follow-up studies on those patient samples demonstrated the importance of long-term continuation of medication for many patients to sustain remission. Overall, these trials highlight the potential of a stable research infrastructure such as CTN to advance treatment effectiveness through a programmatic succession of large clinical trials.
The present study sought to evaluate the secondary wastewater from dairy industry as a culture medium for
Monoraphidium contortum
, in bench-scale tubular photobioreactor, aiming at tertiary ...wastewater treatment and microalgae biomass production. Since the used secondary wastewater contained residual phosphorus (
P
) but negligible residual nitrogen (
N
), we also evaluated the nitrogen supplementation, following Redfield ratio (
N
:
P
= 16:1) and the same
N
:
P
proportion of Bold Medium (
N
:
P
= 1.71:1). These cultures were compared to secondary wastewater without
N
and Bold Medium (control). Secondary wastewater without
N
addition provided lower values of maximum biomass concentration, indicating the importance of this supplementation. The nitrogen supplementation following Bold Medium represented the best protocol, since biomass productivity was higher than that in control culture, but with lower nitrogen addition (in comparison with the supplementation following Redfield proportion). The biomass of
M. contortum
showed to be an excellent candidate for oil production, which could be employed as feedstock for biodiesel, for example.
The aim of this study was to analyze the biological behavior and osteogenic potential of magnesium (Mg) substituted hydroxyapatite (HA) microspheres, implanted in a critical bone defect, considering ...that this ion is of great clinical interest, since it is closely associated with homeostasis and bone mineralization. For the purpose of this study, 30 rats were used to compose three experimental groups: GI - bone defect filled with HA microspheres; GII - bone defect filled with HA microspheres replaced with Mg; GIII - empty bone defect; evaluated at biological points of 15 and 45 days. The histological results, at 15 days, showed, in all the groups, a discrete chronic inflammatory infiltrate; biomaterials intact and surrounded by connective tissue; and bone neoformation restricted to the borders. At 45 days, in the GI and GII groups, an inflammatory response of discrete granulomatous chronic type was observed, and in the GIII there was a scarce presence of mononuclear inflammatory cells; in GI and GII, the microspheres were seen to be either intact or fragmented, surrounded by fibrous connective tissue rich in blood vessels; and discrete bone neoformation near the edges and surrounding some microspheres. In GIII, the mineralization was limited to the borders and the remaining area was filled by fibrous connective tissue. It was concluded that the biomaterials were biocompatible and osteoconductive, and the percentage of Mg used as replacement ion in the HA did not favor a greater bone neoformation in relation to the HA without the metal.
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