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Indirect Rapid Molds for Prototype Lost-Foam Pattern Production 506
Lost-foam (also known as Expendable Pattern Casting, EPC) is an ever-growing metalmcasting technique, capable of producing complex metal components without parting lines. Mold preparation for lost-foam casting is typically accurate, but expensive and slow. The goal of this research was to develop a new approach for producing rapid lost-foam molds. With this new approach, patterns generated by SFF technology are used to form indirect composite lost-foam molds. Ultimately, our objective is to produce these molds quickly, accurately, and inexpensively. This new approach to lost-foam mold-making will be explained as well as the
results of one trial.Mechanical Engineerin
A dual output polarimeter devoted to the study of the Cosmic Microwave Background
We have developed a correlation radiometer at 33 GHz devoted to the search
for residual polarization of the Cosmic Microwave Background (CMB). The two
instruments`s outputs are linear combination of two Stokes Parameters (Q and U
or U and V). The instrument is therefore directly sensitive to the polarized
component of the radiation (respectively linear and circular). The radiometer
has a beam-width oif 7 or 14 deg, but it can be coupled to a telescope
increasing the resolution. The expected CMB polarization is at most a part per
milion. The polarimeter has been designed to be sensitive to this faint signal,
and it has been optimized to improve its long term stability, observing from
the ground. In this contribution the performances of the instrument are
presented, together with the preliminary test and observations.Comment: 12 pages, 6 figures, in print on the Proc. SPIE Conf. - August 200
The main critical issues of the gym environment in an Italian city
BACKGROUND: The lack of a consistent national regulation regarding gym facilities, combined with the growth and transformation of the world of fitness, has led to an uncontrolled situation, where, especially in metropolitan areas, low cost gyms are continuously popping up, often not respecting the structural and hygienic requirements. AIM OF THE STUDY: Objective of this study is to evaluate the results of a monitoring programme about the gym environment, to highlight the main critical issues. METHODS: In 2018 a randomized sample of 90 gyms was inspected in Milan, using a checklist with three sections of inquiry and the resulting data were analysed through a series of multivariate regression models. RESULTS: As per the various aspects analysed, many outcomes with low scores concerned franchised gyms, which have shown to be unsatisfactory in many respects; in addition, the lack of L. pneumophila risk containment procedures has been observed in the facilities without a swimming pool, compared to those with it. CONCLUSIONS: The study results offer a clear picture of the gym environment, identifying many inadequacies for different hygienic and safety aspects; therefore, it has been possible to understand which issues need particular attention in order normalize the situation, which should be checked by future investigative steps
Correlation between CD117+ myeloma plasma cells and hematopoietic progenitor cells in different categories of patients
Background: Multiple myeloma (MM) is a neoplastic disorder of plasma cells interesting mainly the elderly. MM remains an incurable disease, mostly because of the strong interplay between clonal plasma cells (cPCs) and bone marrow (BM) microenvironment. Multiparameter flow cytometry (MFC) allows the simultaneous study of the cPC immunophenotype and alterations involving other cells in BM, but rarely these data are interpreted as connected. One exception to this habit are previous studies about relationship between CD117 cPC positivity and hematopoietic progenitor cell (HPC) distribution in newly diagnosed patients. Thus we were interested in verifying the distribution of BM CD34+ HPCs in healthy controls, and monoclonal gammopathy of undetermined significance (MGUS) patients and various categories of responding/relapsing MM subjects divided according to CD117 positivity. Results: Our data completely agree with precedent reports as regards untreated patients. In the group with progression of disease, CD117- patients exhibited a lower CD34 + CD19-/CD34 + CD19+ ratio vs CD117+ subjects. Among CD117- cases, newly diagnosed patients exhibited differences in distribution of HPCs vs responding myeloma subjects and patients with progressive disease. These differences reached statistical significance comparing CD117- newly diagnosed with CD117- responding cases, as reflected by CD34 + CD19-/CD34 + CD19+ ratio. In turn, no differences emerged comparing CD117+ treated and untreated patients. Conclusions: We demonstrate that administration of treatment and depth of reached response/presence of relapse imply a distinct regulation in distribution of CD34+ HPC subsets in CD117- and CD117+ patients. These differences become evident comparing untreated and treated CD117- patients, but they are impossible to detect in CD117+ cases
Physiological responses to pedaling on a water stationary bike at different immersion heights
Only a few studies[1-4] have investigated oxygen consumption (V’O2) and heart rate (HR) responses to pedaling on a stationary bike in water (WSB), while literature is still lacking on the effects elicited by variations in immersion depth. 14 subjects (8 M, 6 F, age 30±6y, weight 67±14kg, BMI 22.8±2.3kg/m2, fat mass 21,4±3%) performed 2 testing sessions and 2 exercise sessions: i) dry-land incremental exercise test (cycle-ergometer) to age-predicted maximum HR (HR); ii) underwater (hip-height) incremental exercise test (on a WSB) to exhaustion; iii/iv) two 2-stage (18-minutes each) underwater pedaling exercises on a WSB (Aqquatix S.r.l., Italy) at 2 different immersion heights (armpit/hip). Breath-by-breath V’O2 and beat-by-beat HR were recorded continuously throughout dry-land sessions. The intensities of the exercise sessions were 45%-55% (stage#1) and 70%-80% (stage#2) of the underwater V’O2 peak (a metronome was set at the V’O2 peak pedaling rate). A repeated-measures (2 exercise intensities) 2-way (armpit/hip heights) ANOVA was performed on each variable and the Bonferroni test was used for post-hoc comparisons. Compared to the hip-height condition, pedaling immersed at the armpit level elicited significantly lower V’O2 and HR (significant solely at high-intensity for HR) responses, either exercising at high (25.5±4.6 vs. 29.1±4.8 mL∙kg-1∙min-1; 127±14 vs. 140±19 beats∙min-1) or low (17.9±3.6 vs. 20.1±3.6 mL∙kg-1∙min-1; 105±16 vs. 110±15 beats∙min-1) intensity. While peak V’O2 didn’t differ significantly between dry-land and underwater tests (36.2±5.4 vs. 38.8±5.8 mL∙kg-1∙min-1), mean HRs at both intensities and both water heights were significantly lower when expressed as percentage of the HR resulting from the underwater test to exhaustion, rather than applying the 220-age prediction equation.Universidad de Málaga. Campus de Excelencia Internacional AndalucÃa Tech
effectiveness of aquatic therapy in post-surgery rehabilitation of the rotator cuff
Introduction: rotator cuff injuries very often require surgical repair and subsequent rehabilitation. The aim of this study was to compare the effectiveness of a traditional and an aquatic post-surgery rehabilitation program of the rotator cuff in 20 adult (60±5y) patients. Methods:patients were randomly assigned to a traditional (TR; n=10) and to an aquatic (WR; n=10) rehabilitation group. Both programs started 15 days after the surgery, lasted 3 months (3 times-a-week), and consisted in passive mobilization followed by strengthening exercises. The only WR group underwent to an adjunctive aquatic mobilization program. Before (pre-intervention) and after (post-intervention) the programs, patients underwent the following assessments: shoulder range of motion (ROM), in both flexion and extra rotation positions; pain perception (visual analogue scale); simple shoulder test.
Results: pre vs. post-intervention results were compared in each group by means of a dependent-samples t-Test on each variables. An independent-samples t-Test was used to analyze pre-intervention differences between TR and WR groups; since no significant differences were found, the same test was used to analyze post-intervention differences. Pre- vs post-intervention results showed significant improvements in all variables in both groups (p 0,005)
Discussion: although the water-based program did not result more effective than the traditional program at the end of the three months, the aquatic rehabilitation seemed to improve shoulder ROM faster than the traditional one and to be better tolerated by the patients. It’s authors’ opinion that both evidences may increase the adherence to the program during the rest of the rehabilitation programUniversidad de Málaga. Campus de Excelencia Internacional AndalucÃa Tech
Immunological characteristics of non-intensive care hospitalized COVID-19 patients: A preliminary report
Abstract: The outbreak of coronavirus disease 2019 (COVID-19) is posing a threat to global health.
This disease has different clinical manifestations and different outcomes. The immune response
to the novel 2019 coronavirus is complex and involves both innate and adaptive immunity. In
this context, cell-mediated immunity plays a vital role in effective immunity against SARS-CoV-2.
Significant differences have been observed when comparing severe and non-severe patients. Since
these immunological characteristics have not been fully elucidated, we aimed to use cluster analysis
to investigate the immune cell patterns in patients with COVID-19 who required hospitalization but
not intensive care. We identified four clusters of different immunological patterns, the worst being
characterized by total lymphocytes, T helper lymphocytes CD4+
(CD4+
), T cytotoxic lymphocytes
CD8+
(CD8+
) and natural killer (NK) cells below the normal range, together with natural killer
lymphocyte granzyme < 50% (NK granzyme+
) and antibody-secreting plasma cells (ASCs) equal to 0
with fatal outcomes. In the worst group, 50% of patients died in the intensive care unit. Moreover,
a negative trend was found among four groups regarding total lymphocytes, CD4+
, CD8+ and B
lymphocytes (p < 0.001, p < 0.005, p < 0.000, p < 0.044, respectively). This detailed analysis of immune
changes may have prognostic value. It may provide a new perspective for identifying subsets of
COVID-19 patients and selecting novel prospective treatment strategies. Notwithstanding these
results, this is a preliminary report with a small sample size, and our data may not be generalizable.
Further cohort studies with larger samples are necessary to quantify the prognostic value’s weight,
according to immunological changes in COVID-19 patients, for predicting prognoses and realizing
improvements in clinical conditions
BEHAVIOUR OF Aeromonas hydrophila IN SALTED SWORDFISH SAMPLES
A challenge test for Aeromonas hydrophila in salted swordfish samples was carried out. Particularly, 24 samples (250g) were experimentally contaminated, salted and stored at two different temperature regimes (fluctuating – F group - and non fluctuating – NF group – regime). The count of A. hydrophila, Enterobacteria and Lactic acid bacteria (LAB) as well as the determination of pH and aw were performed at 0, 19 43, 163, 187, 230, 320 and 368 hours whereas the temperature was monitored continuously by using 6 data-loggers. In both group, the mean concentrations of A. hydrophila did not exceed Log 3 cfu/g and decreased below the mean value of Log 1 cfu/g after 368 hours. However in the F group the A. hydrophila growth was slower and the decrease appeared slightly higher than NF group and this suggests the temperature fluctuations induces a more pronounced behaviour variability of A. hydrophila under stressing conditions
TRIS I: Absolute Measurements of the Sky Brightness Temperature at 0.6, 0.82 and 2.5 GHz
At frequencies close to 1 GHz the sky diffuse radiation is a superposition of
radiation of Galactic origin, the 3 K Relic or Cosmic Microwave Background
Radiation, and the signal produced by unresolved extragalactic sources. Because
of their different origin and space distribution the relative importance of the
three components varies with frequency and depends on the direction of
observation. With the aim of disentangling the components we built TRIS, a
system of three radiometers, and studied the temperature of the sky at , and GHz using geometrically scaled antennas
with identical beams (HPBW = ). Observations
included drift scans along a circle at constant declination
which provided the dependence of the sky signal on the
Right Ascension, and absolute measurement of the sky temperature at selected
points along the same scan circle. TRIS was installed at Campo Imperatore (lat.
= N, long.= , elevation = 2000 m a.s.l.) in
Central Italy, close to the Gran Sasso Laboratory.Comment: Accepted for publication in The Astrophysical Journa
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