204 research outputs found
Dietary Nutrient Intake and Obesity Prevalence Among Native American Adolescents
The prevalence of obesity among adolescent minority populations has been long recognized, but little research has been done on Native Americans adolescents. Using anthropometric measurements and dietary assessments, the findings within each study have shown to obtain baseline measures to determine the prevalence of obesity within the Sherman Indian High School's Native American adolescent population. Data of each assessment appear to be of use for predicting obesity and creating effective future interventions. Compiling data using the Harvard School of Public Health Youth/Adolescent Questionnaire (HSPH YAQ), a semi-quantitative food frequency questionnaire allowed significant data to be found between normal and obese weight students. Utilizing each finding allows more effective ways of targeting and reversing the inclining rate of obesity among Native American adolescents. Results show that antioxidants being examined on such as vitamin E and lycopene are beneficial in lowering the obesity rate among Native American adolescents. Levels of fiber, thiamin and folate consumption was significantly lower among the obese population in Sherman Indian High School's Native American adolescents. Moreover, dietary mineral intake was shown to be lower among obese Native American adolescents comparing with the normal weight group. The results suggested that dietary consumption of these nutrients might correlate and predict obesity and lead to the development of effective interventions for Native Americans. This study also found the effects of total fiber and vitamin B in diets with lifestyle intervention in prediabetic adults, showing that total fiber intake among the normal weight students is significantly higher than obese students, indicating that fiber and vitamin profile could be important determinants of the effect of dietary intervention
Particle size reduction to the nanometer range: a promising approach to improve buccal absorption of poorly water-soluble drugs
Poorly water-soluble drugs, such as phenylephrine, offer challenging problems for buccal drug delivery. In order to overcome these problems, particle size reduction (to the nanometer range) and cyclodextrin complexation were investigated for permeability enhancement. The apparent solubility in water and the buccal permeation of the original phenylephrine coarse powder, a phenylephrine–cyclodextrin complex and phenylephrine nanosuspensions were characterized. The particle size and particle surface properties of phenylephrine nanosuspensions were used to optimize the size reduction process. The optimized phenylephrine nanosuspension was then freeze dried and incorporated into a multi-layered buccal patch, consisting of a small tablet adhered to a mucoadhesive film, yielding a phenylephrine buccal product with good dosage accuracy and improved mucosal permeability. The design of the buccal patch allows for drug incorporation without the need to change the mucoadhesive component, and is potentially suited to a range of poorly water-soluble compounds
Priprema, identifikacija i antioksidacijska svojstva kelatnog kompleksa željeza i oligopeptida izoliranog iz mesa japanske svilaste crne kokoši (Gallus galllus domesticus Brisson)
Black-bone silky fowl iron(II)-oligopeptide chelate was synthesized from iron(II) solution and the black-bone silky fowl oligopeptide, which was extracted from the muscle protein of black-bone silky fowl (Gallus gallus domesticus Brisson). Orthogonal array analysis was used to determine the optimal conditions for the iron(II)-oligopeptide chelate preparation. Ultraviolet-visible (UV-Vis) spectroscopy, electron microscopy, and Fourier transform infrared (FTIR) spectroscopy were used to identify the structure of iron(II)-oligopeptide chelate. 2-Diphenyl-1-picrylhydrazyl (DPPH) and superoxide radical scavenging assays were performed to compare the antioxidant abilities of the black-bone silky fowl oligopeptide and iron(II)-oligopeptide chelate. The optimal conditions for iron(II) oligopeptide chelate preparation were 4 % of the black-bone silky fowl oligopeptide and a ratio of the black-bone silky fowl oligopeptide to FeCl2·4H2O of 5:1 at pH=4. Under these conditions, the chelation rate was (84.9±0.2) % (p<0.05), and the chelation yield was (40.3±0.1) % (p<0.05). The structures detected with UV-Vis spectroscopy, electron microscopy and FTIR spectra changed significantly after chelation, suggesting that Fe(II) ions formed coordinate bonds with carboxylate (-RCOO¯) and amino (-NH2) groups in the oligopeptides, confirming that this is a new oligopeptide-iron chelate. The iron(II)-oligopeptide chelate had stronger scavenging activity towards DPPH and superoxide radicals than did the black-bone silky fowl oligopeptide.Kelatni kompleks željeza i oligopeptida sintetiziran je dodatkom praha proteina izoliranog iz mesa japanske svilaste crne kokoši (Gallus galllus domesticus Brisson) otopini iona Fe2+. Optimalni uvjeti keliranja određeni su pomoću ortogonalnog plana. Struktura kelata ispitana je pomoću UV-Vis spektroskopije, elektronskog mikroskopa i FTIR spektroskopije. Uspoređena je antioksidacijska aktivnost oligopeptida i kelata, i to ispitivanjem sposobnosti uklanjanja DPPH i superoksidnih radikala. Optimalni uvjeti keliranja bili su: omjer mase oligopeptida i volumena otopine od 4 %, maseni omjer oligopeptida i otopine željezovog(II) klorida od 5:1 i pH-vrijednost od 4. Pri tim je uvjetima uspješnost keliranja bila (84,9±0,2) % (p˂0,05), a prinos kelata (40,3±0,1) % (p˂0,05). Isptivanjem spojeva pomoću UV-Vis spektroskopije, elektronskog mikroskopa i FTIR spektroskopije utvrđeno je da se struktura kelata bitno promijenila, te da je nastao novi spoj, najvjerojatnije vezivanjem iona Fe2+ s karboksilnom i amino skupinom oligopeptida. Kelatni kompleks imao je izraženiju sposobnost uklanjanja DPPH i superoksidnih radikala od oligopeptida
PMET: Precise Model Editing in a Transformer
Model editing techniques modify a minor proportion of knowledge in Large
Language Models (LLMs) at a relatively low cost, which have demonstrated
notable success. Existing methods assume Transformer Layer (TL) hidden states
are values of key-value memories of the Feed-Forward Network (FFN). They
usually optimize the TL hidden states to memorize target knowledge and use it
to update the weights of the FFN in LLMs. However, the information flow of TL
hidden states comes from three parts: Multi-Head Self-Attention (MHSA), FFN,
and residual connections. Existing methods neglect the fact that the TL hidden
states contains information not specifically required for FFN. Consequently,
the performance of model editing decreases. To achieve more precise model
editing, we analyze hidden states of MHSA and FFN, finding that MHSA encodes
certain general knowledge extraction patterns. This implies that MHSA weights
do not require updating when new knowledge is introduced. Based on above
findings, we introduce PMET, which simultaneously optimizes Transformer
Component (TC, namely MHSA and FFN) hidden states, while only using the
optimized TC hidden states of FFN to precisely update FFN weights. Our
experiments demonstrate that PMET exhibits state-of-the-art performance on both
the COUNTERFACT and zsRE datasets. Our ablation experiments substantiate the
effectiveness of our enhancements, further reinforcing the finding that the
MHSA encodes certain general knowledge extraction patterns and indicating its
storage of a small amount of factual knowledge. Our code is available at
https://github.com/xpq-tech/PMET.git.Comment: Preprint. Under revie
Adversarial Perturbations Against Real-Time Video Classification Systems
Recent research has demonstrated the brittleness of machine learning systems
to adversarial perturbations. However, the studies have been mostly limited to
perturbations on images and more generally, classification that does not deal
with temporally varying inputs. In this paper we ask "Are adversarial
perturbations possible in real-time video classification systems and if so,
what properties must they satisfy?" Such systems find application in
surveillance applications, smart vehicles, and smart elderly care and thus,
misclassification could be particularly harmful (e.g., a mishap at an elderly
care facility may be missed). We show that accounting for temporal structure is
key to generating adversarial examples in such systems. We exploit recent
advances in generative adversarial network (GAN) architectures to account for
temporal correlations and generate adversarial samples that can cause
misclassification rates of over 80% for targeted activities. More importantly,
the samples also leave other activities largely unaffected making them
extremely stealthy. Finally, we also surprisingly find that in many scenarios,
the same perturbation can be applied to every frame in a video clip that makes
the adversary's ability to achieve misclassification relatively easy
Experimental observation of magnetic bobbers for a new concept of magnetic solid-state memory
The use of chiral skyrmions, which are nanoscale vortex-like spin textures,
as movable data bit carriers forms the basis of a recently proposed concept for
magnetic solid-state memory. In this concept, skyrmions are considered to be
unique localized spin textures, which are used to encode data through the
quantization of different distances between identical skyrmions on a guiding
nanostripe. However, the conservation of distances between highly mobile and
interacting skyrmions is difficult to implement in practice. Here, we report
the direct observation of another type of theoretically-predicted localized
magnetic state, which is referred to as a chiral bobber (ChB), using
quantitative off-axis electron holography. We show that ChBs can coexist
together with skyrmions. Our results suggest a novel approach for data
encoding, whereby a stream of binary data representing a sequence of ones and
zeros can be encoded via a sequence of skyrmions and bobbers. The need to
maintain defined distances between data bit carriers is then not required. The
proposed concept of data encoding promises to expedite the realization of a new
generation of magnetic solid-state memory
The Difference of Chemical Components and Biological Activities of the Crude Products and the Salt-Processed Product from Semen Cuscutae
Semen Cuscutae is a well-known Chinese medicine which has been used to nourish kidney in China for thousands of years. The crude product of semen Cuscutae (CP) and its salt-processed product (SPP) are separately used in clinic for their different effects. The study was designed to investigate the influence of processing from semen Cuscutae on chemical components and biological effects. The principal component analysis and quantitative analysis were used to study the differences of the chemical components. The effects of nourishing kidney were detected to compare the differences between the CP and SPP. The PCA results showed that the obvious separation was achieved in the CP and SPP samples. The results of quantitative analysis showed that quercetin and total flavonoids had significantly increased after salt processing while hyperoside had decreased. The comparison of CP and SPP on biological activities showed that both of them could ameliorate the kidney-yang deficiency syndrome by restoring the level of sex hormone, improving the immune function and antioxidant effect. However, SPP was better in increasing the level of T and the viscera weight of testicle and epididymis, improving the antioxidant effect. The results suggested that salt processing changed its chemical profile, which in turn enhanced its biological activities
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