1,466 research outputs found

    Delayed versus immediate inoculation of sputum media for diagnosis of pneumonia

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    Are LLMs Rigorous Logical Reasoner? Empowering Natural Language Proof Generation with Contrastive Stepwise Decoding

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    Logical reasoning remains a pivotal component within the realm of artificial intelligence. The recent evolution of large language models (LLMs) has marked significant progress in this domain. The adoption of strategies like chain-of-thought (CoT) has enhanced the performance of LLMs across diverse reasoning tasks. Nonetheless, logical reasoning that involves proof planning, specifically those that necessitate the validation of explanation accuracy, continues to present stumbling blocks. In this study, we first evaluate the efficacy of LLMs with advanced CoT strategies concerning such tasks. Our analysis reveals that LLMs still struggle to navigate complex reasoning chains, which demand the meticulous linkage of premises to derive a cogent conclusion. To address this issue, we finetune a smaller-scale language model, equipping it to decompose proof objectives into more manageable subgoals. We also introduce contrastive decoding to stepwise proof generation, making use of negative reasoning paths to strengthen the model's capacity for logical deduction. Experiments on EntailmentBank underscore the success of our method in augmenting the proof planning abilities of language models

    The Effect of Surface Treatments on Zirconia Bond Strength and Durability

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    To evaluate the effects of airborne particle abrasion (APA) combined with MDP-containing resin cement, a glass-ceramic spray deposition (GCSD) method on the shear bond strengths (SBSs) and durability of 3 mol% yttrium oxide-stabilized zirconia ceramic (3Y-TZP) compared with lithium disilicate glass ceramics (LDGC). 3Y-TZP disks were randomly treated as follows: for Group APA+MDP, 3Y-TZP was abrased using 50 µm Al2O3 particles under 0.1 Mpa and bonded with MDP-containing resin cement; for Group GCSD, 3Y-TZP was treated with the GCSD method, etched by 5% HF for 90 s, silanized and bonded with resin cement without MDP. Group LDGC was bonded as the Group GCSD. X-ray diffraction (XRD), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and energy dispersive X-ray detector (EDX) were used to analyze the surface chemical and micro-morphological changes of the ceramics before bonding. The bonded ceramic specimens were randomly divided into subgroups, and the SBSs were determined before and after 10,000 thermocycling. The SBSs were analyzed with a one-way ANOVA analysis. Failure modes were determined with optical microscopy and SEM. The XRD, ATR-FTIR and XPS results identified the formation of lithium disilicate and zirconium silicate on 3Y-TZP after GCSD. The SEM micrographs revealed that 3Y-TZP surfaces were roughened by APA, while 3Y-TZP with GCSD and LDGC surfaces could be etched by HF to be porous. The APA treatment combined with MDP-containing resin cement produced the high immediate zirconia shear bond strengths (SBSs: 37.41 ± 13.51 Mpa) that was similar to the SBSs of the LDGC (34.87 ± 11.02 Mpa, p > 0.05), but, after thermocycling, the former dramatically decreased (24.00 ± 6.86 Mpa, maximum reduction by 35.85%) and the latter exhibited the highest SBSs (30.72 ± 7.97 Mpa, minimum reduction by 11.9%). The 3Y-TZP with GCSD treatment displayed the lower zirconia SBSs before thermocycling (27.03 ± 9.76 Mpa, p < 0.05), but it was similar to the 3Y-TZP treated with APA and MDP containing resin cement after thermocycling (21.84 ± 7.03 vs. 24.00 ± 6.86 Mpa, p > 0.05). The APA combined with MDP-containing resin cement could achieve the high immediate zirconia SBSs of those of the LDGC, but it decreased significantly after thermocycling. The GCSD technique could yield the immediate zirconia SBSs similar to those of LDGC before thermocycling, and long-term zirconia SBSs were similar to those of 3Y-TZP treated with APA followed by MDP-containing resin cement after thermocycling. Hence, the GCSD technique could enrich zirconia surface treatments and is an alternative to zirconia surface pretreatment for 3Y-TZP bond durability

    Successful treatment of methemoglobinemia in an elderly couple with severe cyanosis: two case reports

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    INTRODUCTION: Methemoglobinemia should be considered in all cyanotic patients who remain unresponsive to oxygen therapy. Rapid diagnosis is very important in emergency cases. Here, we present the cases of two patients, a married couple, admitted to our hospital with methemoglobinemia after exposure to sodium nitrite. CASE PRESENTATION: Two patients, a married couple, presented with methemoglobinemia. The 72-year-old Taiwanese man and 68-year-old Taiwanese woman were referred to our hospital with dizziness and tachypnea. On examination, their mucous membranes were cyanotic, and their blood samples showed the classic ‘chocolate brown’ appearance. The man also reported having experienced twitching of his right arm for a few minutes before arrival at the hospital. The symptoms of both patients failed to improve in response to supplemental oxygen delivered via oxygen masks, although the arterial blood gas data of these patients were normal and their pulse oximetry showed oxyhemoglobin levels of approximately 85%. A carbon monoxide-oximeter showed that the man’s methemoglobin concentration was 48.3%, and the woman’s was 36.4%. Methylene blue (100mg) was administered intravenously to both patients, and their symptoms improved dramatically. They were admitted to the intensive care unit and discharged three days later, without neurological sequelae. CONCLUSION: Severe methemoglobinemia is a life-threatening condition and, if untreated, may result in death. Early diagnosis and appropriate antidotal treatment are crucial in treating this emergency situation

    The electromagnetic decays of X(3823)X(3823) as the ψ2(13D2)\psi_2(1^{3}D_{2}) state and its radial excited states

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    We study the electromagnetic (EM) decays of X(3823)X(3823) as the ψ2(13D2)\psi_2(1^{3}D_{2}) state by using the relativistic Bethe-Salpeter method. Our results are Γ[X(3823)→χc0γ]=1.6\Gamma[X(3823)\rightarrow\chi_{_{c0}}\gamma]=1.6 keV, Γ[X(3823)→χc1γ]=265\Gamma[X(3823)\rightarrow\chi_{_{c1}}\gamma]=265 keV, Γ[X(3823)→χc2γ]=57\Gamma[X(3823)\rightarrow\chi_{_{c2}}\gamma]=57 keV and Γ[X(3823)→ηcγ]=1.3\Gamma[X(3823)\rightarrow\eta_{_c}\gamma]=1.3 keV. The ratio B[X(3823)→χc2γ]/B[X(3823)→χc1γ]=0.22{\cal B}[X(3823)\rightarrow\chi_{_{c2}}\gamma]/{\cal B}[X(3823)\rightarrow\chi_{_{c1}}\gamma]=0.22, agrees with the experimental data. Similarly, the EM decay widths of ψ2(n3D2)\psi_{_2}(n^{3}D_{_2}), n=2,3n=2,3, are predicted, and we find the dominant decays channels are ψ2(n3D2)→χc1(nP)γ\psi_{_2}(n^{3}D_{_2})\rightarrow\chi_{_{c1}}(nP)\gamma, where n=1,2,3n=1,2,3. The wave function include different partial waves, which means the relativistic effects are considered. We also study the contributions of different partial waves.Comment: 20 pages, 6 figures, 9 table

    Evaluation of Epimedium brevicornum Maxim extract for anti-osteoporosis activity in rats

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    Purpose: To evaluate the therapeutic effect of Epimedium brevicornum Maxim. extract (EBME) on ovariectomy-induced osteoporosis in rats.Methods: The rats were divided into six experimental groups, viz, control (group 1) and five ovariectomy-induced (OVX) groups. The OVX groups include OVX-inducing agent only group (group 2), OVX with 17ß-estradiol (E2, 25 μg/kg/day, group 3), OVX with 60 mg EBME/kg body weight/day (group 4), OVX with 120 mg EBME/kg body weight/day (group 5) and OVX with 240 mg EBME/kg body weight/day (group 6). The treatment started for the OVX groups with a single weekly dose of OVX inducing agent for 4 weeks, followed by oral daily dose of E2 (group 3) or EBME (groups 4, 5 and 6) for another 16 weeks. Bone mineral density (BMD) of the 4th lumber vertebrae (4LV) and right femur of each rat was estimated. BMD determination was preceded by the measurement of the length of the femur and identification of diaphysis (center). Trabecular microarchitecture was assessed via three representative 4LV. The other parameters measured in this study were serum alkaline phosphatase (ALP), urinary calcium (U-Ca), urinary phosphorus (U-P), urinary creatinine (U-SCr) and osteocalcin (OC) levels.Result: The results showed that the BMD decrease induced by OVX in 4LV and femur was significantly mitigated by high dose of EBME. EBME also protected the trabecular microarchitecture against OVXassociated deterioration, evidenced by decreased bone turnover marker levels in 4LV at high EBME dose. Trabecular number (Tb-N, 3.7 ± 0.2), trabecular thickness (Tb-Th, 0.082 ± 0.011), and trabecular spacing (Tb-Sp, 0.17 ± 0.01) of the highest dose EBME-treated OVX rats ’4LV were significantly (p &lt; 0.05) different from the corresponding values of EBME-free OVX rats.Conclusion: The results reveal that administration of high doses of EBME lasting for 16 weeks not only protected against OVX-induced osteoporosis in rats but was also without the risk of endometrial hyperplasia. Thus, the extract may be a better alternative to other agents in current use for the treatment of postmenopausal osteoporosis in elderly women. However, its efficacy and safety require further investigations.Keywords: Epimedium brevicornum Maxim., Postmenopausal osteoporosis, Ovariectomy, Bone mineral densit

    Malaria parasites produce volatile mosquito attractants

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    UnlabelledThe malaria parasite Plasmodium falciparum contains a nonphotosynthetic plastid organelle that possesses plant-like metabolic pathways. Plants use the plastidial isoprenoid biosynthesis pathway to produce volatile odorants, known as terpenes. In this work, we describe the volatile chemical profile of cultured malaria parasites. Among the identified compounds are several plant-like terpenes and terpene derivatives, including known mosquito attractants. We establish the molecular identity of the odorant receptors of the malaria mosquito vector Anopheles gambiae, which responds to these compounds. The malaria parasite produces volatile signals that are recognized by mosquitoes and may thereby mediate host attraction and facilitate transmission.ImportanceMalaria is a key global health concern. Mosquitoes that transmit malaria are more attracted to malaria parasite-infected mammalian hosts. These studies aimed to understand the chemical signals produced by malaria parasites; such an understanding may lead to new transmission-blocking strategies or noninvasive malaria diagnostics

    Acid Dissociation of 3-Mercaptopropionic Acid Coated CdSe–CdS/Cd0.5Zn0.5S/ZnS Core–Multishell Quantum Dot and Strong Ionic Interaction with Ca2+ Ion

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    By devising careful electrophoresis, it was shown that at pH below 7.0, the electrophoretic mobility of 3-mercaptopropionic acid (3MPA) coated CdSe–ZnS core–shell quantum dots (denoted as QD-3MPA) was very small. At pH above 7.0, QD-3MPA migrated toward the anode, implying acid dissociation, and the degree of which was proportional to the pH value. QD-3MPA’s electrophoretic mobility was impaired after adding sufficient Ca2+ ions to the QD solution and revived when a similar amount of Ca2+ chelators (ethylene glycol tetraacetic acid, EGTA) was added. This demonstrated that acid dissociation and its pH dependence of 3MPA on the QD surface are critical factors in understanding the electric and optical properties of QDs. The acid dissociated QD-3MPA interacted strongly with Ca2+, forming a charge neutral QD-3MPA–Ca2+ complex in the absence of EGTA. First-principles study confirmed the observed experimental evidence. The strong ionic interaction between acid dissociated QD-3MPA and Ca2+ is critical for developing reliable QD-based biosensing assays. Moreover, the strategy and techniques reported in this work are easily applicable to other fluorescent biomarkers and therefore can be important for advancing in vivo and in vitro imaging, sensing, and labeling

    Detection of subtle neurological alterations by the Catwalk XT gait analysis system

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    BACKGROUND: A new version of the CatWalk XT system was evaluated as a tool for detecting very subtle alteration in gait based on higher speed sample rate; the system could also demonstrate minor changes in neurological function. In this study, we evaluated the neurological outcome of sciatic nerve injury intervened by local injection of hyaluronic acid. Using the CatWalk XT system, we looked for differences between treated and untreated groups and differences within the same group as a function of time so as to assess the power of the Catwalk XT system for detecting subtle neurological change. METHODS: Peripheral nerve injury was induced in 36 Sprague–Dawley rats by crushing the left sciatic nerve using a vessel clamp. The animals were randomized into one of two groups: Group I: crush injury as the control; Group II: crush injury and local application with hyaluronic acid. These animals were subjected to neurobehavior assessment, histomorphology evaluation, and electrophysiology study periodically. These data were retrieved for statistical analysis. RESULTS: The density of neurofilament and S-100 over the distal end of crushed nerve showed significant differences either in inter-group comparison at various time points or intra-group comparison from 7 to 28 days. Neuronal structure architecture, axon counts, intensity of myelination, electrophysiology, and collagen deposition demonstrate significant differences between the two groups. There was significant difference of SFI and angle of ankle in inter- group analysis from 7 to 28 days, but there were no significant differences in SFI and angle of ankle at time points of 7 and 14 days. In the Cat Walk XT analysis, the intensity, print area, stance duration, and swing duration all showed detectable differences at 7, 14, 21, and 28 days, whereas there were no significant difference at 7 and 14 days with CatWalk 7 testing. In addition, there were no significant differences of step sequence or regularity index between the two versions. CONCLUSION: Hyaluronic acid augmented nerve regeneration as early as 7 days after crush injury. This subtle neurological alteration could be detected through the CatWalk XT gait analysis but not the SFI, angle of ankle, or CatWalk 7 methods
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