1,164 research outputs found
Ante el octavo centenario del nacimiento de N. P. Santo Domingo de Guzmán (1170-1970) : breves anotaciones de crítica histórica
Habitability: CAMELOT 4
During 1988 to 1989 the NASA/USRA Advanced Design Program sponsored research and design efforts aimed at developing habitability criteria and at defining a habitability concept as a useful tool in understanding and evaluating dwellings for prolonged stays in extraterrestrial space. The Circulating Auto sufficient Mars-Earth Luxurious Orbital Transport (CAMELOT) was studied as a case in which the students would try to enhance the quality of life of the inhabitants by applying architectural design methodology. The study proposed 14 habitability criteria considered necessary to fulfill the defined habitability concept, which is that state of equilibrium that results from the interaction between components of the Individual Architecture Mission Complex, which allows a person to sustain physiological homeostatis, adequate performance, and acceptable social relationships. Architecture, design development, refinements and revisions to improve the quality of life, new insights on artificial gravity, form and constitution problems, and the final design concept are covered
An overview of the ciao multiparadigm language and program development environment and its design philosophy
We describe some of the novel aspects and motivations behind
the design and implementation of the Ciao multiparadigm programming system. An important aspect of Ciao is that it provides the programmer with a large number of useful features from different programming paradigms and styles, and that the use of each of these features can be turned on and off at will for each program module. Thus, a given module may be using e.g. higher order functions and constraints, while another module may be using objects, predicates, and concurrency. Furthermore, the language is designed to be extensible in a simple and modular way. Another important aspect of Ciao is its programming environment, which provides a powerful preprocessor (with an associated assertion language) capable of statically finding non-trivial bugs, verifying that programs comply with specifications, and performing many types of program optimizations. Such optimizations produce code that is highly competitive with other dynamic languages or, when the highest levéis of optimization are used, even that of static languages, all while retaining the interactive development environment of a dynamic language. The environment also includes a powerful auto-documenter. The paper provides an informal overview of the language and program development environment. It aims at illustrating the design philosophy rather than at being exhaustive, which would be impossible in the format of a paper, pointing instead to the existing literature on the system
New aspects and strategies for methane mitigation from ruminants.
The growing demand for sustainable animal production is compelling researchers to explore the potential approaches to reduce emissions of greenhouse gases from livestock that are mainly produced by enteric fermentation. Some potential solutions, for instance, the use of chemical inhibitors to reduce methanogenesis, are not feasible in routine use due to their toxicity to ruminants, inhibition of efficient rumen function or other transitory effects. Strategies, such as use of plant secondary metabolites and dietary manipulations have emerged to reduce the methane emission, but these still require extensive research before these can be recommended and deployed in the livestock industry sector. Furthermore, immunization vaccines for methanogens and phages are also under investigation for mitigation of enteric methanogenesis. The increasing knowledge of methanogenic diversity in rumen, DNA sequencing technologies and bioinformatics have paved the way for chemogenomic strategies by targeting methane producers. Chemogenomics will help in finding target enzymes and proteins, which will further assist in the screening of natural as well chemical inhibitors. The construction of a methanogenic gene catalogue through these approaches is an attainable objective. This will lead to understand the microbiome function, its relation with the host and feeds, and therefore, will form the basis of practically viable and eco-friendly methane mitigation approaches, while improving the ruminant productivity
Frequency-modulated electromagnetic neural stimulation (FREMS) as a treatment for symptomatic diabetic neuropathy: results from a double-blind, randomised, multicentre, long-term, placebo-controlled clinical trial
AIMS/HYPOTHESIS: The aim was to evaluate the efficacy and safety of
transcutaneous frequency-modulated electromagnetic neural stimulation (frequency
rhythmic electrical modulation system, FREMS) as a treatment for symptomatic
peripheral neuropathy in patients with diabetes mellitus.
METHODS: This was a double-blind, randomised, multicentre, parallel-group study
of three series, each of ten treatment sessions of FREMS or placebo administered
within 3 weeks, 3 months apart, with an overall follow-up of about 51 weeks. The
primary endpoint was the change in nerve conduction velocity (NCV) of deep
peroneal, tibial and sural nerves. Secondary endpoints included the effects of
treatment on pain, tactile, thermal and vibration sensations. Patients eligible
to participate were aged 18-75 years with diabetes for ≥ 1 year, HbA(1c) <11.0%
(97 mmol/mol), with symptomatic diabetic polyneuropathy at the lower extremities
(i.e. abnormal amplitude, latency or NCV of either tibial, deep peroneal or sural
nerve, but with an evocable potential and measurable NCV of the sural nerve), a
Michigan Diabetes Neuropathy Score ≥ 7 and on a stable dose of medications for
diabetic neuropathy in the month prior to enrolment. Data were collected in an
outpatient setting. Participants were allocated to the FREMS or placebo arm (1:1
ratio) according to a sequence generated by a computer random number generator,
without block or stratification factors. Investigators digitised patients' date
of birth and site number into an interactive voice recording system to obtain the
assigned treatment. Participants, investigators conducting the trial, or people
assessing the outcomes were blinded to group assignment.
RESULTS: Patients (n = 110) with symptomatic neuropathy were randomised to FREMS
(n = 54) or placebo (n = 56). In the intention-to-treat population (50 FREMS, 51
placebo), changes in NCV of the three examined nerves were not different between
FREMS and placebo (deep peroneal [means ± SE]: 0.74 ± 0.71 vs 0.06 ± 1.38 m/s;
tibial: 2.08 ± 0.84 vs 0.61 ± 0.43 m/s; and sural: 0.80 ± 1.08 vs -0.91 ± 1.13
m/s; FREMS vs placebo, respectively). FREMS induced a significant reduction in
day and night pain as measured by a visual analogue scale immediately after each
treatment session, although this beneficial effect was no longer measurable 3
months after treatment. Compared with the placebo group, in the FREMS group the
cold sensation threshold was significantly improved, while non-significant
differences were observed in the vibration and warm sensation thresholds. No
relevant side effects were recorded during the study.
CONCLUSIONS/INTERPRETATION: FREMS proved to be a safe treatment for symptomatic
diabetic neuropathy, with immediate, although transient, reduction in pain, and
no effect on NCV.
TRIAL REGISTRATION: ClinicalTrials.gov NCT01628627.
FUNDING: The clinical trial was sponsored by Lorenz Biotech (Medolla, Italy),
lately Lorenz Lifetech (Ozzano dell'Emilia, Italy)
Predicting language diversity with complex network
Evolution and propagation of the world's languages is a complex phenomenon,
driven, to a large extent, by social interactions. Multilingual society can be
seen as a system of interacting agents, where the interaction leads to a
modification of the language spoken by the individuals. Two people can reach
the state of full linguistic compatibility due to the positive interactions,
like transfer of loanwords. But, on the other hand, if they speak entirely
different languages, they will separate from each other. These simple
observations make the network science the most suitable framework to describe
and analyze dynamics of language change. Although many mechanisms have been
explained, we lack a qualitative description of the scaling behavior for
different sizes of a population. Here we address the issue of the language
diversity in societies of different sizes, and we show that local interactions
are crucial to capture characteristics of the empirical data. We propose a
model of social interactions, extending the idea from, that explains the growth
of the language diversity with the size of a population of country or society.
We argue that high clustering and network disintegration are the most important
characteristics of models properly describing empirical data. Furthermore, we
cancel the contradiction between previous models and the Solomon Islands case.
Our results demonstrate the importance of the topology of the network, and the
rewiring mechanism in the process of language change
Performance, carcass and ruminal fermentation characteristics of heifers fed concentrates differing in energy level and cereal type (corn vs. wheat)
A total of 144 beef heifers (218 ± 26.4 kg body weight) were housed in 24 pens (6 animals each) and used in a 168-day feedlot study to evaluate the influence of cereal type and energy level on performance, carcass quality and ruminal fermentation. Four concentrates were formulated according to a 2×2 factorial arrangement of treatments, with two energy levels (1,452 vs. 1,700 kcal net energy/kg) and two main cereals (wheat vs. corn). Concentrate and straw were offered ad libitum. Concentrate intake and body weight were recorded on days 42, 84, 126 and 168. Ruminal fluid was obtained by ruminocentesis from 3 heifers per pen on days 1, 84 and 168; and carcass weight, classification and yield, were determined in the same animals. Heifers fed high-energy diets had lower intake (6.97 vs. 7.29 kg fresh matter/d; p=0.011), and lower concentrate to gain ratio (5.15 vs. 5.66 kg/kg; p=0.002) than those fed low energy concentrates, and tended (p=0.069) to be heavier along the time. Neither carcass yield and classification, nor ruminal pH, volatile fatty acids nor NH3-N concentrations were affected (p>0.050) by energy level. Total volatile fatty acids concentration tended (p=0.070) to be greater in heifers fed corn-based than wheat-based concentrates. No energy level x cereal type interactions were observed. These results indicate that high energy concentrates decreased feed intake and feed conversion but had minor effects on carcass performance. Cereal type had no effects on performance and ruminal fermentation and no interactions between cereal type and energy were detected
Opinion dynamics: models, extensions and external effects
Recently, social phenomena have received a lot of attention not only from
social scientists, but also from physicists, mathematicians and computer
scientists, in the emerging interdisciplinary field of complex system science.
Opinion dynamics is one of the processes studied, since opinions are the
drivers of human behaviour, and play a crucial role in many global challenges
that our complex world and societies are facing: global financial crises,
global pandemics, growth of cities, urbanisation and migration patterns, and
last but not least important, climate change and environmental sustainability
and protection. Opinion formation is a complex process affected by the
interplay of different elements, including the individual predisposition, the
influence of positive and negative peer interaction (social networks playing a
crucial role in this respect), the information each individual is exposed to,
and many others. Several models inspired from those in use in physics have been
developed to encompass many of these elements, and to allow for the
identification of the mechanisms involved in the opinion formation process and
the understanding of their role, with the practical aim of simulating opinion
formation and spreading under various conditions. These modelling schemes range
from binary simple models such as the voter model, to multi-dimensional
continuous approaches. Here, we provide a review of recent methods, focusing on
models employing both peer interaction and external information, and
emphasising the role that less studied mechanisms, such as disagreement, has in
driving the opinion dynamics. [...]Comment: 42 pages, 6 figure
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