Rubber-like materials exhibit a particular stress–strain behaviour known as hyperelasticity. Several models are available in the literature for these materials, based on the definition of a ...particular expression of the specific potential deformation energy. Among these, Mooney–Rivlin and Ogden models are the most used. In both cases, at least uniaxial and biaxial stretching tests are required to fit the model and extract material parameters. In this work, an experimental rig was set up to carry out equi-biaxial tests: the classic bulge test method has been coupled with optical devices allowing measurement in real time of the stress and elongation levels of the specimen. Uniaxial stretching tests were performed by means of a standard tensile machine and a video extensometer. Quasi-static experimental results were used to calibrate hyperelastic models. Finally, a planar tension test was carried out to validate the material models fitted from uniaxial and equi-biaxial data. FEM simulations of the test procedures give a useful comparison between numerical and experimental data.
Decolourisation of the recalcitrant dye Remazol Brilliant Blue R (RBBR) by the fungus basidiomycete
Pleurotus ostreatus was investigated.
P. ostreatus is able to decolourise RBBR on agar plate. When ...grow in liquid media supplemented with veratryl alcohol, the fungus completely decolourises RBBR in 3 days. In these conditions,
P. ostreatus produces among other enzymes, laccases, veratryl alcohol oxidase and dye-decolourising peroxidase but only laccases seem to be responsible of RBBR transformation. Two purified laccases (POXC and POXA3) were found able to degrade RBBR in vitro, in the absence of any redox mediators. These laccases differ significantly in their efficiency of decolourisation of the tested dye, as suggested by comparison of their catalytic efficiency (
k
cat/
K
m values) towards RBBR. Furthermore, using a mixture of both POXC and POXA3 a remarkable improvement in the reaction rate and in the final level of dye decolourisation was observed. The extent of RBBR decolourisation by laccase mixture also depends on incubation temperature and enzyme concentration. The dye is decolorised by laccase isoenzymes most efficiently under acidic conditions. Treatment of RBBR with the laccase mixture reduced its toxicity by 95%.
Cognitive dysfunction affects 40–65% of multiple sclerosis (MS) patients and can occur in the early stages of the disease. This study aimed to explore cognitive functions by means of the Italian ...version of the minimal assessment of cognitive function in MS (MACFIMS) in relapsing-remitting MS (RRMS) patients with very mild clinical disability to identify the primarily involved cognitive functions. Ninety-two consecutive RRMS patients with Expanded Disability Status Scale (EDSS) scores ≤ 2.5 and forty-two healthy controls (HC) were investigated. Our results show that 51.1% of MS patients have cognitive dysfunction compared to HC. An impairment of verbal and visual memory, working memory, and executive functions was found in the RRMS group. After subgrouping RRMS by EDSS, group 1 (EDSS ≤ 1.5) showed involvement of verbal memory and executive functions; moreover, group 2 (2 ≤ EDSS ≤ 2.5) patients were also impaired in information processing speed and visual memory. Our results show that utilizing a comprehensive neuropsychological assessment, approximately half of MS patients with very mild physical disability exhibit cognitive impairment with a primary involvement of prefrontal cognitive functions. Detecting impairment of executive functions at an early clinical stage of disease could be useful to promptly enroll MS patients in targeted rehabilitation.
Our main aim was to investigate the short-term thera-peutic effects, safety/tolerability of natural compound, composed of melatonin (1,5 mg) and cannabis extracts (2.5 mg CBD) in patients with sleep ...disorders.
In this spontaneous, anecdotal, retrospective, "compas-sionate-use," observational, open-label study, 20 patients (age 43-96 years) were appealed to our "Second Opinion Medical Consulting Net-work" (Modena, Italy), because of a variable pattern of sleep disorders and anxiety and were instructed to take sublingually the compound (20 drops) overnight for 3 months of treatment. Tolerability and adverse effects were assessed monthly during the treatment period through direct contact (email or telephone) or visit if required.
PSQUI and HAM-A scores evidenced reduction in mood alterations, including anxiety, panic, paranoia, depression (P < 0.03), in pain (P < 0.02) and good general health perceptions.
These data suggest that the formula CBD-melatonin could be competitive with the classic hypnotic synthetic drugs, the antioxidant activity of melatonin offers a further benefit to the brain network, restoring the biological clock functions, while CBD, redu-cing chronic pain perception, helps to complete the neuromuscular relaxation and to relieve anxiety fulfilling a very balanced sensation of wellbeing during the sleep.
Taking any
p
>
1
, we consider the asymptotically
p
-linear problem
-
div
(
a
(
x
,
u
,
∇
u
)
)
+
A
t
(
x
,
u
,
∇
u
)
=
λ
∞
|
u
|
p
-
2
u
+
g
∞
(
x
,
u
)
in
Ω
,
u
=
0
on
∂
Ω
,
where
Ω
is a bounded ...domain in
R
N
,
N
≥
2
,
A
(
x
,
t
,
ξ
)
is a real function on
Ω
×
R
×
R
N
which grows with power
p
with respect to
ξ
and has partial derivatives
A
t
(
x
,
t
,
ξ
)
=
∂
A
∂
t
(
x
,
t
,
ξ
)
,
a
(
x
,
t
,
ξ
)
=
∇
ξ
A
(
x
,
t
,
ξ
)
. If
A
(
x
,
t
,
ξ
)
→
A
∞
(
x
,
t
)
and
g
∞
(
x
,
t
)
|
t
|
p
-
1
→
0
as
|
t
|
→
+
∞
, suitable assumptions, variational methods and either the cohomological index theory or its related pseudo-index one, allow us to prove the existence of multiple nontrivial bounded solutions in the
non-resonant case
, i.e. if
λ
∞
is not an eigenvalue of the operator associated to
∇
ξ
A
∞
(
x
,
ξ
)
. In particular, while in
14
the model problem
A
(
x
,
t
,
ξ
)
=
A
(
x
,
t
)
|
ξ
|
p
with
p
>
N
is studied, here our goal is twofold: extending such results not only to a more general family of functions
A
(
x
,
t
,
ξ
)
, but also to the more difficult case
1
<
p
≤
N
.
Background
Androgenetic alopecia (AGA) is a prevalent genetic condition that can affect both male and female, and is considered the most frequent form of hair loss. Traditional scales and methods of ...classifying AGA are basically qualitative.
Objective
This work aims to propose a quantitative scale to classify AGA in order to assist hair transplantation surgery.
Methods
Based on whole hairless and thinning areas that needs to receive follicular units in a hair transplantation procedure, basic equations to support the scale are proposed. Additionally, the study involves simulations that apply the classification system and compare its results with those of qualitative methods.
Results
The PRECISE scale utilizes a range of 0–10, using 30 cm
2
as the measured standard of a bald area. For hair transplantation, 1500 follicular units (FU) are recommended for each score in the PRECISE scale. Technological and manual methods to measure the hairless and thinning areas are presented and discussed. This new quantitative classification, combined with different and complementary methods of measurement of hairless and thinning areas endorse the understanding of the clinical condition by the patient and the planning of a surgery procedure.
Conclusion
The developed PRECISE scale brings a different way of classifying Androgenetic alopecia (AGA), through an essentially quantitative evaluation. It can be used to elaborate the best strategy for the hair transplantation surgery and to improve the outcomes.
Level of Evidence V
This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based medicine ratings, please refer to the Table of Contents or the online Instructions to Authors
www.springer.com/00266
.
Appropriate knowledge of viscoelastic properties of polymers and elastomers is of fundamental importance for a correct modelization and analysis of structures where such materials are present, ...especially when dealing with dynamic and vibration problems. In this paper experimental results of a series of compression and tension tests on specimens of styrene-butadiene rubber and polypropylene plastic are presented; tests consist of creep and relaxation tests, as well as cyclic loading at different frequencies. Experimental data are then used to calibrate some linear viscoelastic models; besides the classical approach based on a combination in series or parallel of standard mechanical elements as springs and dashpots, particular emphasis is given to the application of models whose constitutive equations are based on differential equations of fractional order (Fractional Derivative Model). The two approaches are compared analyzing their capability to reproduce all the experimental data for given materials; also, the main computational issues related with these models are addressed, and the advantage of using a limited number of parameters is demonstrated.
In this paper we look for weak solutions of the quasilinear elliptic model problem −div(A(x,u)∇u)+12At(x,u)|∇u|2=g(x,u)+h(x)in Ω,u=0on ∂Ω,where Ω⊂RN is a bounded domain, N≥2, the real terms A(x,t), ...At(x,t)=∂A∂t(x,t) and g(x,t) are Carathéodory functions on Ω×R and h:Ω→R is a given measurable map.
We prove that, even if At(x,t)≢0, under suitable assumptions infinitely many solutions exist in spite of the lack of symmetry. A suitable supercritical growth is allowed for the nonlinear term g(x,t).
We use a variant of the variational perturbation techniques introduced by Rabinowitz in Rabinowitz (1982) but by means of a weak version of the Cerami–Palais–Smale condition.
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