189 research outputs found
Chinese Word Order and the Two Typological Exceptions: A Scalar Approach
Conventional discussions on the VO/OV typology highlight two perceived
"exceptions" in Chinese word order, particularly concerning the placement of
relative clauses and adpositional phrases. In this paper, we argue that these
seemingly exceptional Chinese word order patterns align with the broader
linguistic tendencies of the language rather than being genuine deviations from
typological norms. To demonstrate this, we analyze Chinese word orders across
15 parameters and attempt to rank them on a scalar continuum, comparing
them to other languages. We assign a score of [-1] to the head-initial pattern
parameter, [+1] to the head-final pattern parameter, and [0] for patterns
accommodating both. Chinese is expected to exhibit a head-initial tendency;
however, the data does not align with this expectation. Notably, it manifests a
strong head-final tendency in NPs and VPs, achieving a [+6] score that aligns
it closely with OV languages. Consequently, the placement of relative clauses
and adpositional phrases in Chinese conforms to the typical pattern of OV
languages, and thus, it need not be considered exceptional
Direct Preference-based Policy Optimization without Reward Modeling
Preference-based reinforcement learning (PbRL) is an approach that enables RL
agents to learn from preference, which is particularly useful when formulating
a reward function is challenging. Existing PbRL methods generally involve a
two-step procedure: they first learn a reward model based on given preference
data and then employ off-the-shelf reinforcement learning algorithms using the
learned reward model. However, obtaining an accurate reward model solely from
preference information, especially when the preference is from human teachers,
can be difficult. Instead, we propose a PbRL algorithm that directly learns
from preference without requiring any reward modeling. To achieve this, we
adopt a contrastive learning framework to design a novel policy scoring metric
that assigns a high score to policies that align with the given preferences. We
apply our algorithm to offline RL tasks with actual human preference labels and
show that our algorithm outperforms or is on par with the existing PbRL
methods. Notably, on high-dimensional control tasks, our algorithm surpasses
offline RL methods that learn with ground-truth reward information. Finally, we
show that our algorithm can be successfully applied to fine-tune large language
models.Comment: NeurIPS 202
Neutrophil extracellular traps and heparin-induced antibodies contribute to vascular access thrombosis in hemodialysis patients
Background Anti-heparin/platelet factor 4 (PF4) antibodies may trigger severe thrombotic complications in hemodialysis (HD) patients. Tetrameric PF4 has a high affinity for extracellular DNA, which is a key component of neutrophil extracellular traps (NETs); therefore, the interactions between anti-heparin/PF4 antibodies and NETs can contribute to prothrombotic events. Methods Anti-heparin/PF4 antibody levels were measured by enzyme-linked immunosorbent assay and an optical density > 1.8 was regarded as clinically significant. We additionally measured serum nucleosome levels as representative markers of NETs, and the contributions of anti-heparin/PF4 and increased serum nucleosome levels to the primary functional patency loss of vascular access was assessed. Results The frequency of anti-heparin/PF4 antibodies was significantly higher in incident HD patients compared to prevalent HD patients (23.6% vs. 7.7%). Serum nucleosome levels, as well as the white blood cell counts, neutrophil counts, and high- sensitivity C-reactive protein levels, were significantly higher in anti-heparin/PF4 antibody-positive patients compared to the control. Platelet counts tended to be lower in the patients with anti-heparin/PF4 of >1.8 than in the controls. Relative risk calculations showed that the presence of anti-heparin/PF4 antibodies increased the risk of primary functional patency failure by 4.28-fold, and this risk increased further with higher nucleosome levels. Furthermore, in the anti-heparin/PF4 antibody-positive group, the time to first vascular intervention was much shorter, and the risk of repeated intervention was higher, compared to the controls. Conclusion In incident HD patients, the presence of anti-heparin/PF4 antibodies was associated with increased NET formation; this could be a strong predictor of vascular access complication
High-flow arteriovenous fistula and myocardial fibrosis in hemodialysis patients with non-contrast cardiac magnetic resonance imaging
BackgroundThe role of high-flow arteriovenous fistula (AVF) in cardiovascular morbidity in hemodialysis (HD) patients is very likely under-recognized. We assessed the relationship between high access flow (Qa) and myocardial fibrosis in HD patients.MethodsMyocardial fibrosis was assessed by native T1 relaxation times on non-contrast cardiac magnetic resonance imaging and a potential marker of fibrosis. Serum levels of galectin-3, N-terminal pro-B-type natriuretic peptide (NT-proBNP), and monocyte chemoattractant protein 1 (MCP-1) were measured in 101 HD patients who underwent regular monitoring of AVF Qa. A high-flow AVF was defined as a Qa >2 L/min.ResultsHemodialysis patients showed significantly higher galectin-3 value and increased T1 relaxation time compared to healthy volunteers, suggesting increased myocardial fibrosis in uremic cardiomyopathy. In HD patients, 20 (19.8%) had a Qa > 2L/min, and they had significantly higher cardiac output, cardiac index, left ventricular mass, and increased T1 times than those with a Qa ≤ 2 L/min. Also, serum galectin-3 and NT-proBNP levels were much higher in the high Qa group, indicating a close relationship between the high Qa, increased myocardial fibrosis, and the risk of heart failure (HF) in HD patients. It is interesting that a higher AVF Qa for myocardial fibrosis was independent of several traditional cardiovascular risk factors as well as serum levels of NT-proBNP and MCP-1.ConclusionsA supra-physiologically high Qa can be related to myocardial fibrosis and increased risk of HF in HD patients. Regular Qa monitoring could allow early detection of a high-flow AVF that could arise cardiac complications
Hyperghrelinemia does not accelerate gastric emptying in Prader-Willi syndrome patients
Prader-Willi syndrome (PWS) is the most common form of syndromic obesity associated with hyperphagia. Because ghrelin stimulates gastric motility in rodents, and PWS patients have 3- to 4-fold higher fasting plasma ghrelin concentrations than normal subjects, we hypothesized that hyperphagia associated with PWS may be partly explained by rapid gastric emptying due to the increased gastric motility caused by ghrelin. We determined gastric emptying times (GETs) and measured ghrelin levels in 11 PWS children and 11 age-, sex-, and body mass index-matched controls using a standard meal containing [(99m)Tc]diaminetriaminepentacetate. Median plasma ghrelin levels before (precibum) and after the GET study were higher in PWS patients than in controls (P = 0.004 and P = 0.001, respectively). Median percent gastric retentions at 90 min after the standard meal were 57.1% (range, 34.0-83.2%) in PWS patients and 40.2% (range, 27.2-60.2%) in controls (P = 0.03). In particular, precibum ghrelin concentrations were not significantly correlated with the rate of gastric emptying in PWS patients (P = 0.153; r = 0.461) or controls (P = 0.911; r = 0.048). Our results show that gastric emptying in PWS is reduced despite higher ghrelin levels, and that the voracious appetite associated with PWS is related to another mechanism
Associated Factors of Quality of Life in First-Episode Schizophrenia Patients
OBJECTIVE: Improving quality of life is an important goal in the treatment of schizophrenia. In previous research, quality of life has been reported to be compromised in patients with schizophrenia. The aim of this study was to investigate whether quality of life may be impaired in first-episode schizophrenia patients and to identify the associated factors of quality of life in first-episode schizophrenia.
METHODS: Forty-eight patients with first-episode schizophrenia and 20 normal controls were recruited. Quality of life was measured by using the Quality of Life scale (QLS). General and social self-efficacy, perceived social support were measured by using the self-report scales. The clinical assessments and comprehensive neurocognitive battery were also administered.
RESULTS: First-episode group showed significantly decreased QLS total and QLS subscale scores compared to normal controls group. The key associated factors of quality of life in patients with first-episode schizophrenia were the negative symptoms and social self-efficacy.
CONCLUSION: This finding implies that compromised quality of life may be already emerged in schizophrenia in their first-episode and the psychosocial interventions should be targeting the negative symptoms and the psychosocial protective factors including self-efficacy in addition to simply ameliorating the positive symptoms to foster social reintegration and recovery of first-episode patients.ope
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