137 research outputs found

    Pengaruh Suhu dan Waktu Pemanasan terhadap Kandungan Vitamin A dan C pada Proses Pembuatan Pasta Tomat

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    Buah tomat (Lycopersicum esculentum Mill) termasuk sayuran buah yang banyak disukai karena rasanya enak dan segar. Kualitas tomat dapat ditinjau dari rasa manis, asam, kekenyalan, dan jumlah air buah. Tujuan penelitian ini adalah untuk mempelajari hubungan suhu dan waktu pemanasan terhadap kadar vitamin A dan C dan untuk mengetahui suhu pemanasan yang optimum serta mempelajari kinetika degradasi termal pada pembuatan pasta tomat. Metode penelitian ini sebagai berikut mula-mula tomat yang sudah diblender dipanaskan dengan suhu tertentu, tiap selang waktu tertentu sampel diambil untuk dianalisis kadar vitamin C, A dan kadar padatan terlarut. Selain itu juga dianalisis konsentrasi vitamin C dalam tomat. Analisis ini dilakukan dengan beberapa metode antara lain titrasi iodometri, dan analisis dengan spektrofotometer. Dari hasil penelitian diperoleh kesimpulan bahwa: 1. semakin lama waktu pemanasan kadar padatan terlarut dalam pasta tomat semakin besar sehingga dan nilai kadar tersebut sesuai dengan SNI 01-3546-2004 yaitu minimum 24%. Untuk pengaruh suhu pemanasan yang semakin tinggi maka penurunan kadar vitamin C semakin besar, dan juga penurunan kadar vitamin A semakin besar akibat terdegradasi oleh panas; 2. reaksi degradasi termal vitamin C dalam pasta tomat mengikuti reaksi orde satu, sehingga diperoleh nilai ko dan E untuk reaksi tersebut adalah ko=0,6126 menit -1dan E=3.292,08 cal/mol

    Electrophysiological correlates of high-level perception during spatial navigation

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    We studied the electrophysiological basis of object recognition by recording scalp\ud electroencephalograms while participants played a virtual-reality taxi driver game.\ud Participants searched for passengers and stores during virtual navigation in simulated\ud towns. We compared oscillatory brain activity in response to store views that were targets or\ud nontargets (during store search) or neutral (during passenger search). Even though store\ud category was solely defined by task context (rather than by sensory cues), frontal ...\ud \u

    Neutrino oscillations from relativistic flavor currents

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    By resorting to recent results on the relativistic currents for mixed (flavor) fields, we calculate a space-time dependent neutrino oscillation formula in Quantum Field Theory. Our formulation provides an alternative to existing approaches for the derivation of space dependent oscillation formulas and it also accounts for the corrections due to the non-trivial nature of the flavor vacuum. By exploring different limits of our formula, we recover already known results. We study in detail the case of one-dimensional propagation with gaussian wavepackets both in the relativistic and in the non-relativistic regions: in the last case, numerical evaluations of our result show significant deviations from the standard formula.Comment: 16 pages, 4 figures, RevTe

    CSF proteomics in autosomal dominant Alzheimer's disease highlights parallels with sporadic disease

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    Autosomal dominant Alzheimer's disease (ADAD) offers a unique opportunity to study pathophysiological changes in a relatively young population with few comorbidities. A comprehensive investigation of proteome changes occurring in ADAD could provide valuable insights into AD-related biological mechanisms and uncover novel biomarkers and therapeutic targets. Furthermore, ADAD might serve as a model for sporadic AD, but in-depth proteome comparisons are lacking. We aimed to identify dysregulated CSF proteins in ADAD and determine the degree of overlap with sporadic AD. We measured 1472 proteins in CSF of PSEN1 or APP mutation carriers (n = 22) and age- and sex-matched controls (n = 20) from the Amsterdam Dementia Cohort using proximity extension-based immunoassays (PEA). We compared protein abundance between groups with two-sided t-tests and identified enriched biological pathways. Using the same protein panels in paired plasma samples, we investigated correlations between CSF proteins and their plasma counterparts. Finally, we compared our results with recently published PEA data from an international cohort of sporadic AD (n = 230) and non-AD dementias (n = 301). All statistical analyses were false discovery rate-corrected. We detected 66 differentially abundant CSF proteins (65 increased, 1 decreased) in ADAD compared to controls (q &lt; 0.05). The most strongly upregulated proteins (fold change &gt;1.8) were related to immunity (CHIT1, ITGB2, SMOC2), cytoskeletal structure (MAPT, NEFL) and tissue remodelling (TMSB10, MMP-10). Significant CSF-plasma correlations were found for the upregulated proteins SMOC2 and LILR1B. Of the 66 differentially expressed proteins, 36 had been measured previously in the sporadic dementias cohort, 34 of which (94%) were also significantly upregulated in sporadic AD, with a strong correlation between the fold changes of these proteins in both cohorts (rs = 0.730, P &lt; 0.001). Twenty-nine of the 36 proteins (81%) were also upregulated among non-AD patients with suspected AD co-pathology. This CSF proteomics study demonstrates substantial biochemical similarities between ADAD and sporadic AD, suggesting involvement of the same biological processes. Besides known AD-related proteins, we identified several relatively novel proteins, such as TMSB10, MMP-10 and SMOC2, which have potential as novel biomarkers. With shared pathophysiological CSF changes, ADAD study findings might be translatable to sporadic AD, which could greatly expedite therapy development.</p

    Managing deliberate self-harm in young people: An evaluation of a training program developed for school welfare staff using a longitudinal research design

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    BACKGROUND: Although deliberate self-harm is prevalent among young people, many who engage in deliberate self-harm receive sub-optimal care. Although schools are a well placed setting to support young people who engage in self-harm there are no specific training packages designed to assist school welfare staff to support these young people.The current study aimed to design, deliver and evaluate a training course specifically for school staff. METHODS: The study employed a longitudinal design. Two hundred and thirteen people participated in the training and evaluation. A questionnaire was administered at baseline, immediately after the training and at 6-month follow-up in order to determine if the training led to improvements in confidence when working with young people who self-harm, perceived skill, knowledge of, and attitudes towards people who self harm. RESULTS: Prior to the course, the majority of participants demonstrated relatively high levels of confidence, perceived skill and knowledge of self-harm and endorsed relatively positive attitudes towards people who engage in self-harm. Despite this, significant improvements were observed in terms of increased confidence, increased perceptions of skill along with increased knowledge of deliberate self-harm. These improvements were sustained over the follow-up period. CONCLUSION: The results demonstrated that the provision of specifically designed training can help school welfare staff to feel better equipped to support young people who are engaging in deliberate self-harm

    Translation Levels Control Multi-Spanning Membrane Protein Expression

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    Attempts to express eukaryotic multi-spanning membrane proteins at high-levels have been generally unsuccessful. In order to investigate the cause of this limitation and gain insight into the rate limiting processes involved, we have analyzed the effect of translation levels on the expression of several human membrane proteins in Escherichia coli (E. coli). These results demonstrate that excessive translation initiation rates of membrane proteins cause a block in protein synthesis and ultimately prevent the high-level accumulation of these proteins. Moderate translation rates allow coupling of peptide synthesis and membrane targeting, resulting in a significant increase in protein expression and accumulation over time. The current study evaluates four membrane proteins, CD20 (4-transmembrane (TM) helixes), the G-protein coupled receptors (GPCRs, 7-TMs) RA1c and EG-VEGFR1, and Patched 1 (12-TMs), and demonstrates the critical role of translation initiation rates in the targeting, insertion and folding of integral membrane proteins in the E. coli membrane

    LRR-RLK family from two Citrus species: Genome-wide identification and evolutionary aspects

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    Background: Leucine-rich repeat receptor-like kinases (LRR-RLKs) represent the largest subfamily of plant RLKs. The functions of most LRR-RLKs have remained undiscovered, and a few that have been experimentally characterized have been shown to have important roles in growth and development as well as in defense responses. Although RLK subfamilies have been previously studied in many plants, no comprehensive study has been performed on this gene family in Citrus species, which have high economic importance and are frequent targets for emerging pathogens. In this study, we performed in silico analysis to identify and classify LRR-RLK homologues in the predicted proteomes of Citrus clementina (clementine) and Citrus sinensis (sweet orange). In addition, we used large-scale phylogenetic approaches to elucidate the evolutionary relationships of the LRR-RLKs and further narrowed the analysis to the LRR-XII group, which contains several previously described cell surface immune receptors. Results: We built integrative protein signature databases for Citrus clementina and Citrus sinensis using all predicted protein sequences obtained from whole genomes. A total of 300 and 297 proteins were identified as LRR-RLKs in C. clementina and C. sinensis, respectively. Maximum-likelihood phylogenetic trees were estimated using Arabidopsis LRR-RLK as a template and they allowed us to classify Citrus LRR- 34 RLKs into 16 groups. The LRR-XII group showed a remarkable expansion, containing approximately 150 paralogs encoded in each Citrus genome. Phylogenetic analysis also demonstrated the existence of two distinct LRR-XII clades, each one constituted mainly by RD and non-RD kinases. We identified 68 orthologous pairs from the C. clementina and C. sinensis LRR-XII genes. In addition, among the paralogs, we identified a subset of 78 and 62 clustered genes probably derived from tandem duplication events in the genomes of C. clementina and C. sinensis, respectively. Conclusions: This work provided the first comprehensive evolutionary analysis of the LRR-RLKs in Citrus. A large expansion of LRR-XII in Citrus genomes suggests that it might play a key role in adaptive responses in host-pathogen co-evolution, related to the perennial life cycle and domestication of the citrus crop species
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