Enhancing Friction Pendulum Isolation Systems Using Passive and Semi-Active Dampers

Friction pendulum systems (FPSs) are a common solution for isolating civil engineering structures under ground movements. The result is a base-isolated structure in which the base exhibits low shear stiffness in such a way that the input energy of the earthquake is concentrated and dissipated into it, leaving the superstructure free of damage. As a consequence, large displacements of the FPS may be demanded depending on the earthquake intensity and the fundamental period of the FPS. To accommodate these displacements, large-size isolators with high friction coefficients are usually required. However, the FPS will then exhibit poor re-centering capacity and the risk of future shocks will increase due to previous residual displacements, especially for low-intensity earthquakes. An alternative solution is to include a semi-active damper to the FPS, keeping the friction coefficient low and achieving both, limited base displacement under high-intensity earthquakes and good re-centering capacity under low-intensity ones. Thus, this work presents a design methodology for base isolators formed by an FPS with a damper added. The design methodology is applied to an FPS with a passive damper and to an FPS with a semi-active damper. Two ON-OFF control strategies are studied: (i) a fairly simple phase control, and (ii), a mechanical energy-predictive based algorithm. The advantages of semi-active FPSs with low friction coefficients with respect to FPS with high friction coefficients are demonstrated. The results with the designed semi-active FPS are compared with the single FPS and the FPS with a passive damper. Finally, the use of semi-active FPS allows us to enhance the FPS performance as the isolator size can be reduced while keeping the capacity to cope with low and high-intensity earthquakes without residual displacements.

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Selective Ablation of Cancer Cells with Low Intensity Pulsed Ultrasound

10.1101/779124 ◽

2019 ◽

Author(s):

David R. Mittelstein ◽

Jian Ye ◽

Erika F. Schibber ◽

Ankita Roychoudhury ◽

Leyre Troyas Martinez ◽

...

Keyword(s):

Cancer Cells ◽

High Intensity ◽

Focused Ultrasound ◽

Mechanical Energy ◽

Pulsed Ultrasound ◽

High Intensity Ultrasound ◽

Low Intensity Pulsed Ultrasound ◽

Low Intensity ◽

Specific Frequency ◽

Acoustic Standing Waves

ABSTRACTUltrasound can be focused into deep tissues with millimeter precision to perform non-invasive ablative therapy for diseases such as cancer. In most cases, this ablation uses high intensity ultrasound to deposit non-selective thermal or mechanical energy at the ultrasound focus, damaging both healthy bystander tissue and cancer cells. Here we describe an alternative low intensity pulsed ultrasound approach that leverages the distinct mechanical properties of neoplastic cells to achieve inherent cancer selectivity. We show that when applied at a specific frequency and pulse duration, focused ultrasound selectively disrupts a panel of breast, colon, and leukemia cancer cell models in suspension without significantly damaging healthy immune or red blood cells. Mechanistic experiments reveal that the formation of acoustic standing waves and the emergence of cell-seeded cavitation lead to cytoskeletal disruption, expression of apoptotic markers, and cell death. The inherent selectivity of this low intensity pulsed ultrasound approach offers a potentially safer and thus more broadly applicable alternative to non-selective high intensity ultrasound ablation.

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Inhibition rather than Enhancement of Hemostatic System Activation during Initiation of Oral Anticoagulant Treatment

Thrombosis and Haemostasis ◽

10.1055/s-0038-1656034 ◽

1997 ◽

Vol 77 (04) ◽

pp. 685-689 ◽

Cited By ~ 11

Author(s):

Paul A Kyrle ◽

Johannes Brockmeier ◽

Ansgar Weltermann ◽

Sabine Eichinger ◽

Wolfgang Speiser ◽

...

Keyword(s):

High Intensity ◽

Oral Anticoagulant ◽

Protein C ◽

Venous Blood ◽

Rapid Decline ◽

Oral Anticoagulant Treatment ◽

Shed Blood ◽

Low Intensity ◽

Hemostatic System ◽

System Activation

SummaryCoumarin-induced skin necrosis is believed to be due to a transient hypercoagulable state resulting from a more rapid decline of the protein C activity relative to that of coagulation factors (F) II, IX and X during initiation of oral anticoagulant therapy. We studied hemostatic system activation during early oral anticoagulant treatment with a technique that investigates coagulation activation in the microcirculation.We determined in 10 healthy volunteers the concentrations of prothrombin fragment F1+2 (f1.2) and thrombin-antithrombin complex (TAT) in blood emerging from an injury of the microvasculature (bleeding time incision) before and after initiation of both high-inten- sity and low-intensity coumarin therapy. In addition, f1.2, TAT, activated F VII (F Vila) and the activities of FII, F VII, F X and protein C were measured in venous blood.A rapid decline of F VII and protein C was observed in venous blood with activities at 24 h of 7 ± 1% and 43 ± 2%, respectively, during the high-intensity regimen. A 20 to 30% reduction of f1.2 and TAT was seen in venous blood at 72 h with no major difference between the high- and the low-intensity regimen. F Vila levels were substantially affected by anticoagulation with a >90% reduction at 48 h during the high-intensity regimen. Following high-intensity coumarin, a >50% decrease in the fl.2 and TAT levels was found in shed blood at 48 h suggesting substantial inhibition of thrombin generation during early oral anticoagulation. An increase in the f1.2 and TAT levels was seen neither in shed blood nor in venous blood.Our data do not support the concept of a transient imbalance between generation and inhibition of thrombin as the underlying pathomechanism of coumarin-induced skin nekrosis.

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Pulsed high intensity laser versus low intensity laser on healing of full thickness wound in diabetic rats (histological and immunohistochemical study)

International Journal of Pharma and Bio Sciences ◽

10.22376/ijpbs.2017.8.2.b874-888 ◽

2017 ◽

Vol 8 (2) ◽

Cited By ~ 2

Author(s):

HESHAMGALAL MAHRAN ◽

EMAN MOHAMED FARUK ◽

NASER A. ELSAWY ◽

WARDAHABDULLAH MOHAMMED ALASMARI ◽

ABDULLAH GLILRADA ALKUSHI

Keyword(s):

High Intensity ◽

Immunohistochemical Study ◽

Diabetic Rats ◽

Full Thickness ◽

Low Intensity ◽

High Intensity Laser ◽

Intensity Laser ◽

Full Thickness Wound

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Contralateral training effects of low-intensity blood-flow restricted and high-intensity unilateral resistance training

European Journal of Applied Physiology ◽

10.1007/s00421-021-04708-2 ◽

2021 ◽

Author(s):

Goncalo V. Mendonca ◽

Carolina Vila-Chã ◽

Carolina Teodósio ◽

André D. Goncalves ◽

Sandro R. Freitas ◽

...

Keyword(s):

Blood Flow ◽

Resistance Training ◽

High Intensity ◽

Training Effects ◽

Low Intensity

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Comparison of two different models of rehabilitation programs following total knee replacement operations

Egyptian Rheumatology and Rehabilitation ◽

10.1186/s43166-020-00034-1 ◽

2020 ◽

Vol 47 (1) ◽

Author(s):

Rabab S. Zaghlol ◽

Sahar S. Khalil ◽

Ahmed M. Attia ◽

Ghada A. Dawa

Keyword(s):

Total Knee Replacement ◽

Knee Replacement ◽

High Intensity ◽

Rating Scale ◽

Rehabilitation Program ◽

Low Intensity ◽

Rehabilitation Programs ◽

Patient Reported ◽

Total Knee ◽

Functional Gain

Abstract Background Total knee replacement operation (TKR) is the treatment of choice in severe knee osteoarthritis (OA). Rehabilitation post-TKR is still not well studied. The aim of this study was to compare between the high-intensity (HI) rehabilitation program and the low-intensity (LI) rehabilitation program following TKR. Results At 1 month following the TKR operations, significant improvements were found in the first group compared to the second group in all the measured parameters except for the knee range of motion (ROM). At 3 and 12 months follow-up periods, there were statistically significant differences between both groups in all the evaluated parameters except for the numeric pain rating scale and the knee ROM. Conclusions Both high-intensity and low-intensity rehabilitation programs are effective; however, HI program had superior functional gain and patient-reported outcomes compared to the LI program. Moreover, HI group has a long-term functional gain.

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Concentration of roselle (Hibiscus sabdariffa L) and sucrose in beverages: Effects on physicochemical characteristics and acceptance

Food Science and Technology International ◽

10.1177/1082013220973796 ◽

2020 ◽

pp. 108201322097379

Author(s):

Jahir Antonio Barajas-Ramírez ◽

Ana Luisa Gutiérrez-Salomón ◽

Sonia Guadalupe Sáyago-Ayerdi

Keyword(s):

Antioxidant Activity ◽

Phenolic Compounds ◽

High Intensity ◽

Physicochemical Characteristics ◽

Hibiscus Sabdariffa ◽

Color Parameters ◽

Low Intensity ◽

Red Color

The calyces of roselle ( Hibiscus sabdariffa L.) are used to make a refreshing drink with high content of anthocyanins and other phenolic compounds, although the process for obtaining the beverage is not standardized. In this research it was determined physicochemical characteristics, total soluble polyphenols content, antioxidant activity and acceptance for beverages prepared by decoction at four concentrations of calyces in water (1.0, 2.5, 5.0 and 10.0%) and two concentrations of sucrose (11 and 16%). Color parameters in beverages permitted to describe them as red, which turned darker as the content of hibiscus increased. Total soluble polyphenols content and antioxidant activity were directly correlated with content of calyces in beverages and inversely correlated with pH, which means that beverages with higher content of calyces could be perceived as more acidic and more intense in characteristics associated with hibiscus presence, such as acid, astringent and the presence of intense dark red color, although the higher concentration of sucrose might have contributed to mask slightly the sourness and astringency. Acceptance for hibiscus beverages allowed to observe two segments of consumers, high-intensity and low-intensity likers but both confluence in overall liking values for beverages prepared with 2.5% calyces and 16% sucrose.

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Competences Required for the Delivery of High and Low-Intensity Cognitive Behavioural Interventions for Chronic Fatigue, Chronic Fatigue Syndrome/ME and Irritable Bowel Syndrome

Behavioural and Cognitive Psychotherapy ◽

10.1017/s1352465814000290 ◽

2014 ◽

Vol 42 (6) ◽

pp. 760-764 ◽

Cited By ~ 5

Author(s):

Katharine A. Rimes ◽

Janet Wingrove ◽

Rona Moss-Morris ◽

Trudie Chalder

Keyword(s):

Irritable Bowel Syndrome ◽

Chronic Fatigue Syndrome ◽

High Intensity ◽

Chronic Fatigue ◽

Behavioural Interventions ◽

Low Intensity ◽

Fatigue Syndrome ◽

Cognitive Behavioural ◽

Irritable Bowel ◽

Cognitive Behavioural Interventions

Background: Cognitive behavioural interventions are effective in the treatment of chronic fatigue, chronic fatigue syndrome (sometimes known as ME or CFS/ME) and irritable bowel syndrome (IBS). Such interventions are increasingly being provided not only in specialist settings but in primary care settings such as Improving Access to Psychological Therapies (IAPT) services. There are no existing competences for the delivery of “low-intensity” or “high-intensity” cognitive behavioural interventions for these conditions. Aims: To develop “high-intensity” and “low-intensity” competences for cognitive behavioural interventions for chronic fatigue, CFS/ME and IBS. Method: The initial draft drew on a variety of sources including treatment manuals and other information from randomized controlled trials. Therapists with experience in providing cognitive behavioural interventions for CF, CFS/ME and IBS in research and clinical settings were consulted on the initial draft competences and their suggestions for minor amendments were incorporated into the final versions. Results: Feedback from experienced therapists was positive. Therapists providing low intensity interventions reported that the competences were also helpful in highlighting training needs. Conclusions: These sets of competences should facilitate the training and supervision of therapists providing cognitive behavioural interventions for chronic fatigue, CFS/ME and IBS. The competences are available online (see table of contents for this issue: http://journals.cambridge.org/jid_BCP) or on request from the first author.

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Service Use, Drop-Out Rate and Clinical Outcomes: A Comparison Between High and Low Intensity Treatments in an IAPT Service

Behavioural and Cognitive Psychotherapy ◽

10.1017/s1352465813000544 ◽

2014 ◽

Vol 42 (6) ◽

pp. 747-759 ◽

Cited By ~ 16

Author(s):

Stella W. Y. Chan ◽

Malcolm Adams

Keyword(s):

Clinical Outcomes ◽

High Intensity ◽

Recovery Rate ◽

Service Use ◽

Evaluation Study ◽

Drop Out ◽

Stepped Care ◽

Depression And Anxiety ◽

Low Intensity ◽

Drop Out Rate

Background: The IAPT services provide high and low intensity psychological treatments for adults suffering from depression and anxiety disorders using a stepped care model. The latest national evaluation study reported an average recovery rate of 42%. However, this figure varied widely between services, with better outcomes associated with higher “step-up” rates between low and high intensity treatments. Aims: This study aimed to compare the two intensity groups in an IAPT service in Suffolk. Method: This study adopted a between groups design. A sample of 100 service users was randomly selected from the data collected from an IAPT service in Suffolk between May 2008 and February 2011. The treatment outcomes, drop-out rate, and other characteristics were compared between those who received high and low intensity treatments. Results: The high intensity group received, on average, more sessions and contact time. They received more CBT sessions and less guided self-help. There were no group differences in terms of the drop-out and appointment cancellation rates. Analyses on clinical outcomes suggested no group difference but demonstrated an overall recovery rate of 52.6% and significant reduction in both depression and anxiety symptoms. Conclusions: Despite methodological limitations, this study concludes that the service as a whole achieved above-average clinical outcomes. Further research building upon the current study in unpacking the relative strengths and weaknesses for the high and low intensity treatments would be beneficial for service delivery.

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Therapist Characteristics and their Effect on Training Outcomes: What Counts?

Behavioural and Cognitive Psychotherapy ◽

10.1017/s1352465814000642 ◽

2015 ◽

Vol 43 (3) ◽

pp. 374-380 ◽

Cited By ~ 2

Author(s):

Amanda Branson ◽

Roz Shafran

Keyword(s):

High Intensity ◽

Clinical Performance ◽

Clinical Skill ◽

Individual Characteristics ◽

Therapist Characteristics ◽

Training Outcomes ◽

Low Intensity ◽

Cognitive Behavioural ◽

The Impact ◽

And Training

Background:Evidence exists for a relationship between individual characteristics and both job and training performance; however relationships may not be generalizable. Little is known about the impact of therapist characteristics on performance in postgraduate therapist training programmes.Aims:The aim of this study was to investigate associations between the grades of trainee Low-Intensity and High-Intensity cognitive behavioural therapists and individual characteristics.Method:Trainee Low-Intensity (n= 81) and High-Intensity (n= 59) therapists completed measures of personality and cognitive ability; demographic and course grade data for participants were collected.Results:Degree classification emerged as the only variable to be significantly associated with performance across assessments and courses. Higher undergraduate degree classifications were associated with superior academic and clinical performance. Agreeableness was the only dimension of personality to be associated (positively) with clinical skill. Age was weakly and negatively associated with performance.Conclusions:Relationships between individual characteristics and training outcomes are complex and may be context specific. These results could have important implications for the selection and development of therapists for Low or High-Intensity cognitive behavioural therapy (CBT) training.

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