237 research outputs found
The Effects of the Use of Plyometric Exercises with and without the Ball in the Development of Explosive Strength in Volleyball
Volleyball primarily focuses on technical and tactical training with a ball. However, there is growing interest in integrating fitness training into volleyball practice, particularly to enhance explosive strength through plyometric methods, but there is a lack of a direct scientific comparison between training with and without the ball. This study aimed to compare the effects of two training protocols on volleyball players. One protocol combined plyometric exercises with technical gestures (wall drills) using the ball, while the other protocol excluded the ball during plyometric exercises. Twenty male volleyball players (aged 18.6 ± 0.3 years, height 189.8 ± 2.2 cm, weight 79.4 ± 1.6 kg) were divided into experimental (with ball) and control (without ball) groups. The analysis of the results highlights significant improvements in both the squat jumps (SJs) and the countermovement jumps with arm swing (CMJas) for both groups. While there were no significant differences between the groups for SJ, significant differences emerged in CMJas, indicating varied training effects. Specifically, the interaction effect was significant (p = 0.004), demonstrating a meaningful distinction in performance improvements between the two groups. The effect size of the interaction is moderate (ηp2 = 0.37, 95% CI: 0; 0.91). These results suggest that incorporating a ball into plyometric training can be beneficial for developing explosive strength in a different way, thereby improving performance due to the motivational stimulus provided. However, given the specificity of the sample and the training protocols used, further studies are needed to confirm these results and evaluate their applicability to a larger sample of volleyball players
Fatal Hepatocellular Carcinoma in a Patient with Occult Hepatitis B Virus Infection following the Administration of R-CHOP for Diffuse Large B-Cell Lymphoma
Occult hepatitis B (OBI) is caused by a persistent low-level replication of HBV. Like overt HBV infection, OBI can be associated with the integration of HBV sequences into the host genome and has a substantial clinical relevance for patients who are severely immunosuppressed for long durations. We present the case of a patient with a diffuse large B-cell non-Hodgkin lymphoma and OBI who developed a hepatocellular carcinoma with a fulminant clinical course following the administration of rituximab plus CHOP
Thyroid function, autoimmunity and nodules in hematological malignancies
Objective Hematological malignancies encompass a large spectrum of disease entities whose treatment by chemo/radiotherapy could lead to thyroid complications. To the best of our knowledge, no study has simultaneously addressed thyroid function, autoimmunity and nodularity. Therefore, we decided to conduct one.Materials and methods We evaluated 82 Caucasian patients (36 women and 46 men), who were treated at our Oncology division for hematological malignancies (multiple myeloma, chronic myeloid leukemia, chronic lymphatic leukemia, non-Hodgkin lymphoma and polycythemia vera) and compared them with a control group of 104 patients. Patients who had received or were receiving external head/neck radiotherapy were excluded. All oncological patients and control individuals underwent thyroid ultrasonography and thyroid function and autoimmunity tests.Results A lower prevalence of enlarged thyroid and nodules were found in patients with respect to controls. The rate of thyroid nodules was the highest in multiple myeloma and polycythemia vera, and the lowest in chronic lymphatic leukemia. Non-Hodgkin lymphoma patients had the smallest thyroid nodules while men with multiple myeloma the biggest ones. No patient had hypothyroidism, while 5.6% of patients had subclinical hyperthyroidism. In contrast, within the control group the rates of hypothyroidism and hyperthyroidism, overt and subclinical, were 3.8%, 20.2%, 0% and 0% respectively. Moreover, the overall rate of thyroid autoantibody positiveness in patients was significantly lower than controls.Conclusion In our experience, we found a significantly lower prevalence of thyroid abnormalities in hematologic patients who underwent chemotherapy, but not radiotherapy, with respect to controls. Arch Endocrinol Metab. 2015;59(3):236-4
Anchoring the Yield Curve Using Survey Expectations
The dynamic behavior of the term structure of interest rates is difficult to replicate with models, and even models with a proven track record of empirical performance have underperformed since the early 2000s. On the other hand, survey expectations are accurate predictors of yields, but only for very short maturities. We argue that this is partly due to the ability of survey participants to incorporate information about the current state of the economy as well as forward-looking information such as that contained in monetary policy announcements. We show how the informational advantage of survey expectations about short yields can be exploited to improve the accuracy of yield curve forecasts given by a base model. We do so by employing a flexible projection method that anchors the model forecasts to the survey expectations in segments of the yield curve where the informational advantage exists and transmits the superior forecasting ability to all remaining yields. The method implicitly incorporates into yield curve forecasts any information that survey participants have access to, without the need to explicitly model it. We document that anchoring delivers large and significant gains in forecast accuracy for the whole yield curve, with improvements of up to 52% over the years 2000-2012 relative to the class of models that are widely adopted by financial and policy institutions for forecasting the term structure of interest rates
Efficacy of treatment with glycosaminoglycans on experimental collagen-induced arthritis in rats
To evaluate the antioxidant activity of the glycosaminoglycans hyaluronic acid (HYA) and chondroitin-4-sulphate (C4S), we used a rat model of collagen-induced arthritis (CIA). Arthritis was induced in Lewis rats by multiple intradermal injections of 250 Όl of emulsion containing bovine type II collagen in complete Freund's adjuvant at the base of the tail and into three to five other sites on the back. Rats were challenged again with the same antigen preparation 7 days later. Disease developed about 11 days after the second immunization. The effects of treatment in the rats were monitored by biochemical parameters and by macroscopic and histological evaluations in blood, synovial tissue and articular cartilage. Arthritis produced the following symptoms: severe periarticular erythema, edema and inflammation in the hindpaws; membrane peroxidation in the cartilage of the joints; endogenous antioxidant wasting; high tumour necrosis factor-α (TNF-α) plasma levels; and synovial neutrophil accumulation. Treatment with HYA and C4S, starting at the onset of arthritis for 10 days, limited the erosive action of the disease in the articular joints of knee and paw, reduced lipid peroxidation, restored the endogenous antioxidants reduced glutathione (GSH) and superoxide dismutase, decreased plasma TNF-α levels, and limited synovial neutrophil infiltration. These data confirm that erosive destruction of the joint cartilage in CIA is due at least in part to free radicals released by activated neutrophils and produced by other biochemical pathways. The beneficial effects obtained with the treatment suggest that HYA and C4S could be considered natural endogenous macromolecules to limit erosive damage in CIA or as a useful tool with which to study the involvement of free radicals in rheumatoid arthritis
Secondary Leukemia in a non-Hodgkin's Lymphoma Patient Presenting as Myeloid Sarcoma of the Breast
As defined by the World Health Organization classification of tumors of hematopoietic and lymphoid tissue, myeloid sarcoma (MS) is a tumor mass of myeloblasts or immature myeloid cells that can arise before, concurrent with, or following acute myeloid leukaemia. We describe a case of secondary leukemia presenting itself as MS of the breast in a patient previously treated for a non-Hodgkin's Lymphoma
Optical tracking of deep-space spacecraft in Halo L2 orbits and beyond: the Gaia mission as a pilot case
We tackle the problem of accurate optical tracking of distant man-made
probes, on Halo orbit around the Earth-Sun libration point L2 and beyond, along
interplanetary transfers. The improved performance of on-target tracking,
especially when observing with small-class telescopes is assessed providing a
general estimate of the expected S/N ratio in spacecraft detection. The
on-going Gaia mission is taken as a pilot case for our analysis, reporting on
fresh literature and original optical photometry and astrometric results. The
probe has been located, along its projected nominal path, within 0.13 +/- 0.09
arcsec, or 0.9 +/- 0.6 km. Spacecraft color appears to be red, with (V-R_c) =
1.1 +/- 0.2 and a bolometric correction to the R_c band of (Bol-R_c) = -1.1 +/-
0.2. The apparent magnitude, R_c = 20.8 +/- 0.2, is much fainter than
originally expected. These features lead to suggest a lower limit for the Bond
albedo a = 0.11 +/- 0.05 and confirm that incident Sun light is strongly
reddened by Gaia through its on-board MLI blankets covering the solar shield.
Relying on the Gaia figures, we found that VLT-class telescopes could yet be
able to probe distant spacecraft heading Mars, up to 30 million km away, while
a broader optical coverage of the forthcoming missions to Venus and Mars could
be envisaged, providing to deal with space vehicles of minimum effective area
Aeff >= 10^6 cm^2. In addition to L2 surveys, 2m-class telescopes could also
effectively flank standard radar-ranging techniques in deep-space probe
tracking along Earth's gravity-assist maneuvers for interplanetary missions.Comment: In press for Advances in Space Research (w/ 15 colour figures and 1
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Geo Satellitesâ Manufacturing Markers From Photometric Colors
We present the photometric analysis of 23 GEO satellites, by using more than 1,200 multi-band images acquired in the Johnson-Cousin photometric system (BVRI). The dataset was acquired by three optical telescopes geographically located in different observational sites (in Italy and Mexico). By using an observational strategy based on alternating the V-R-I filter-sequence, we obtained consecutive multi-band images we used to reconstruct satellitesâ color-lightcurves. We calculated the color-indexes of GEO satellites by taking into account the average value of color-lightcurves. We investigated the color-indexes in the color-color planes. Moreover, we studied a possible correlation among colors and satellite manufacturing and peculiar features.
We obtained that some of the considered parameters seem to significantly affect the color indexes
Neural correlates of outcome of cognitive therapy compared to psychodynamic therapy in affective disorders. a meta-analysis
Anxiety and depression disorders are commonly associated with structural and functional changes in the fronto-limbic brain areas. However, it is still unexplored how different psychotherapeutic approaches affect the functional brain. The present meta-analysis aims to compare the neurobiological outcome of the cognitive therapies compared to the psychodynamic therapies in anxiety and depression disorders
Malignant Perivascular Epithelioid Cell Tumor of the Esophagus
Malignant perivascular epithelioid cell tumor (PEComa) is a rare tumor composed of hybrid tumor cells characterized by immunoreactivity for both melanocytic and smooth muscle markers. This paper describes the uncommon esophageal location of an 8âcm PEComa in a 75-year-old Caucasian man who was presented with ingravescent dysphagia. Although PEComas arising within the gastrointestinal tract are exceptional findings, clinicians should not exclude this class of tumors in the diagnostic investigation of a bulky lesion of the esophageal wall
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