1,223 research outputs found
On the Computational Complexity of the Strong Geodetic Recognition Problem
A strong geodetic set of a graph~ is a vertex set~
in which it is possible to cover all the remaining vertices of~ by assigning a unique shortest path between each vertex pair of~. In the
Strong Geodetic problem (SG) a graph~ and a positive integer~ are given
as input and one has to decide whether~ has a strong geodetic set of
cardinality at most~. This problem is known to be NP-hard for general
graphs. In this work we introduce the Strong Geodetic Recognition problem
(SGR), which consists in determining whether even a given vertex set~ is strong geodetic. We demonstrate that this version is
NP-complete. We investigate and compare the computational complexity of both
decision problems restricted to some graph classes, deriving polynomial-time
algorithms, NP-completeness proofs, and initial parameterized complexity
results, including an answer to an open question in the literature for the
complexity of SG for chordal graphs
An Empirical Study of Using Large Language Models for Unit Test Generation
A code generation model generates code by taking a prompt from a code
comment, existing code, or a combination of both. Although code generation
models (e.g. GitHub Copilot) are increasingly being adopted in practice, it is
unclear whether they can successfully be used for unit test generation without
fine-tuning. We investigated how well three generative models (Codex,
GPT-3.5-Turbo, and StarCoder) can generate test cases to fill this gap. We used
two benchmarks (HumanEval and Evosuite SF110) to investigate the context
generation's effect in the unit test generation process. We evaluated the
models based on compilation rates, test correctness, coverage, and test smells.
We found that the Codex model achieved above 80% coverage for the HumanEval
dataset, but no model had more than 2% coverage for the EvoSuite SF110
benchmark. The generated tests also suffered from test smells, such as
Duplicated Asserts and Empty Tests.Comment: Preprint submitted to Journal of Systems and Software; 36 pages, 4
figures, 7 table
Effects of High-Fat Diet on eHSP72 and Extra-to-Intracellular HSP70 Levels in Mice Submitted to Exercise under Exposure to Fine Particulate Matter
Obesity, air pollution, and exercise induce alterations in the heat shock response (HSR), in both intracellular 70?kDa heat shock proteins (iHSP70) and the plasmatic extracellular form (eHSP72). Extra-to-intracellular HSP70 ratio (H-index?=?eHSP70/iHSP70 ratio) represents a candidate biomarker of subclinical health status. This study investigated the effects of moderate- and high-intensity exercise in the HSR and oxidative stress parameters, in obese mice exposed to fine particulate matter (PM2.5). Thirty-day-old male isogenic B6129F2/J mice were maintained for 16 weeks on standard chow or high-fat diet (HFD). Then, mice were exposed to either saline or 50?µg of PM2.5 by intranasal instillation and subsequently maintained at rest or subjected to moderate- or high-intensity swimming exercise. HFD mice exhibited high adiposity and glucose intolerance at week 16th. HFD mice submitted to moderate- or high-intensity exercise were not able to complete the exercise session and showed lower levels of eHSP70 and H-index, when compared to controls. PM2.5 exposure modified the glycaemic response to exercise and modified hematological responses in HFD mice. Our study suggests that obesity is a critical health condition for exercise prescription under PM2.5 exposure
CHARCOAL BRIQUETTES PRODUCED WITH RECYCLED COCONUT PITH
O presente trabalho teve como objetivo produzir briquetes com finos de
carv\ue3o de res\uedduos de coco e avaliar a qualidade dos
briquetes. Cascas de coco foram coletadas no APL de coco em Touros -
RN. Ap\uf3s secagem ao ar livre por dois meses, as cascas foram
carbonizadas em forno de alvenaria tipo \u201crabo quente JG\u201d e
trituradas em moinho de martelo. O p\uf3 resultante foi peneirado,
utilizando-se a fra\ue7\ue3o inferior a 40 mesh para
produ\ue7\ue3o de briquetes em um delineamento inteiramente
casualizado envolvendo 12 tratamentos (divididos em tr\ueas grupos) e
tr\ueas repeti\ue7\uf5es. Como aglutinantes, foram empregados
amido de milho e argila. Os tratamentos foram divididos em tr\ueas
grupos, correspondendo cada grupo a uma propor\ue7\ue3o de argila,
respectivamente 12, 15 e 18%, em rela\ue7\ue3o ao peso seco total
do briquete. Em cada grupo, as propor\ue7\uf5es de amido foram de
6, 8, 10 e 12%. O p\uf3 de carv\ue3o foi misturado com a argila
finamente triturada e a seguir foi adicionado o amido
pr\ue9-gelatinizado em \ue1gua a 80\ub0C. A massa para cada
tratamento foi misturada at\ue9 completa homogeneiza\ue7\ue3o,
separando-se quantidades de 17 gramas de massa por repeti\ue7\ue3o.
Os briquetes foram produzidos em briquetadeira de laborat\uf3rio, com
press\ue3o de 1.500 psi e tempo de prensagem de quatro minutos. Foram
avaliadas as seguintes propriedades dos briquetes: densidade aparente,
poder calor\uedfico, composi\ue7\ue3o qu\uedmica imediata
(umidade, teores de carbono fixo, mat\ue9rias vol\ue1teis e cinzas)
e resist\ueancia \ue0 compress\ue3o. Os melhores tratamentos para
fins comerciais foram os 12/12 e 12/15.The present work has the objective to produce briquettes by using fine
charcoal from coconut wastes as raw material and evaluate the briquette
quality. Coconut piths were collected at the city of Touros, in Rio
Grande do Norte state. After a 2- month air drying, coconut pith was
carbonized and hereafter ground in a hammer mill. The resulting
charcoal powder was sieved and the fraction less than 40 mesh was used
to produce briquettes according to an entirely randomized designed
experiment involving 12 treatments and 3 replications. Starch and clay
were employed as binders. The treatments were divided into 3 groups,
each group corresponding to a proportion of clay, respectively 12, 15
and 18%, based on the total dry weight of the briquette. Within each
group, the proportions of starch were 6, 8, 10 and 12%. The carbon
powder was mixed with finely ground clay was added and then the
pre-gelatinized starch in water at 80\ub0C. The mass for each
treatment was mixed until homogeneous, separating quantities of 17grams
of mass for each repetition. The briquettes were produced in a
laboratory press (pressure of 1500psi and pressing time of 4 minutes).
The briquettes were dried in an oven at 60\ub0C until constant
weight. After drying, the properties of briquettes were evaluated: bulk
density, high calorific value, immediate chemical composition (moisture
content, fixed carbon, volatile matter and ash) and compressive
strength. Best treatments for trading products were 12/12 e 12/15
Dance training improves cytokine secretion and viability of neutrophils in diabetic patients
Background. Evidence suggests that exercise improves neutrophil function. The decreased functional longevity of neutrophils and their increased clearance from infectious sites contribute to the increased susceptibility to infection and severity of infection observed in patients with diabetes. Objective. Herein, we investigated the effects of a dance program on neutrophil number, function, and death in type 2 diabetes mellitus (T2DM) patients and healthy volunteers. Methods. Ten patients with T2DM and twelve healthy individuals participated in a moderate-intensity dance training program for 4 months. The plasma levels of leptin, free fatty acids (FFAs), tumour necrosis factor-α (TNF-α), C-reactive protein (CRP), interleukin-1β (IL-1β), and interleukin-1 receptor antagonist (IL-1ra); neutrophil counts; extent of DNA fragmentation; cell membrane integrity; and production of TNF-α, interleukin-8 (IL-8), interleukin-6 (IL-6), and IL-1β in neutrophils were measured before and after training. Results. Training reduced plasma levels of TNF-α (1.9-fold in controls and 2.2-fold in patients with T2DM) and CRP (1.4-fold in controls and 3.4-fold in patients with T2DM). IL-1ra levels were higher in the control group (2.2-fold) after training. After training, neutrophil DNA fragmentation was decreased in patients with T2DM (90%), while the number of neutrophils increased (70% in controls and 1.1-fold in patients with T2DM). Conclusion. Dance training is a nonpharmacological strategy to reduce inflammation and improve neutrophil clearance in patients with T2DM
A survey of the eutrophication state of an urbanized tropical estuary, the case of the Great Vitória Estuarine System, Brazil.
Although, estuarine ecosystems have an ecological and economical importance as they have a high biological productivity and occur within a unique and dynamic environment, they have been subjected to anthropogenic alterations. The Great Vitória Estuarine System (GVES), Espírito Santo State, Brazil, is not an exception, as urbanization is growing around it with a high quantity of sewage been added to the system. In order to evaluate the eutrophication state as well as the meiofauna response to it, several parameters in both sediments and in the water column were assessed. Orthophosphate, nitrite, nitrate, ammonia, chla and Fecal Coliform counts (FC) ranged from 0.2 to 3.2 μM, 0.25 to 1.14 μM, 1.83 to 0.19μM, 4.19 to 49.23 μM, 0.61 to 6.72 μg/L and 14 to 5.0x104 MPN/100 mL of water, respectively. These results showed that the GVES is under an eutrophication process and that the Passagem Channel experienced the largest impacts. Sewage plays an important role in this eutrophication process as indicated by PCA and correlations tests. The density of meiofauna showed similar values to those found in environments with similar levels of anthropogenic stress. This multi-approach evaluation revealed several aspects of the impacted estuary and could be used as an important tool to manage better the estuary.Although, estuarine ecosystems have an ecological and economical importance as they have a high biological productivity and occur within a unique and dynamic environment, they have been subjected to anthropogenic alterations. The Great Vitória Estuarine System (GVES), Espírito Santo State, Brazil, is not an exception, as urbanization is growing around it with a high quantity of sewage been added to the system. In order to evaluate the eutrophication state as well as the meiofauna response to it, several parameters in both sediments and in the water column were assessed. Orthophosphate, nitrite, nitrate, ammonia, chla and Fecal Coliform counts (FC) ranged from 0.2 to 3.2 μM, 0.25 to 1.14 μM, 1.83 to 0.19μM, 4.19 to 49.23 μM, 0.61 to 6.72 μg/L and 14 to 5.0x104 MPN/100 mL of water, respectively. These results showed that the GVES is under an eutrophication process and that the Passagem Channel experienced the largest impacts. Sewage plays an important role in this eutrophication process as indicated by PCA and correlations tests. The density of meiofauna showed similar values to those found in environments with similar levels of anthropogenic stress. This multi-approach evaluation revealed several aspects of the impacted estuary and could be used as an important tool to manage better the estuary
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