274 research outputs found
The design and fabrication of a thermal microprobe integrated on an atomic force microscope probe tip
A thermal microprobe has been designed and built for high resolution temperature sensing. The thermal microprobe consists of a very-thin-film thermocouple junction confined to the very end of a low mass Atomic Force Microscope (AFM) probe tip. Essential to high resolution temperature sensing is the confinement of the thermocouple junction to a short distance at the AFM tip. This confinement is achieved by controlled photoresist coating.
Experimental prototypes have been made with the junction confined to within 0.3 µm of the tip. The couple is made of Au/Pd, and the two metals are electrically separated elsewhere by a thin insulating layer. The device is designed for insertion in an AFM instrument so that topographical and thermal images can be made with the same tip. Large contact pads permit mechanical and ohmic contacting with spring clamps.
Processing begins with double-polished, n-type, 4-inch-diameter, and 300 µm thick silicon wafers. Probe tips are formed by a combination of RIE, wet chemical etching, and oxidation sharpening, which makes the tips atomically sharp. The hot thermocouple junction is formed by controlled photoresist coating. The metal layers are sputtering deposited and the cantilevers are released by KOH etching and RIE.
The thermal microprobe gives a high temperature resolution and a high spatial resolution. The thermal mass is kept low in order to cause minimal disturbance of the component under measurement. The thermal output of the microprobe is 5.6 µV/°C and is linear over the temperature range 25 - 110°C
Rapid Detection of Troponin I from Serum using Microwave-Accelerated Metal-Enhanced Fluorescence
The dyadic self-care experience of stroke survivors and their caregivers: A qualitative descriptive study
background promoting self-care is the core response strategy of the global health system to the burden of stroke. although self-care in stroke represents a dyadic phenomenon, the dyadic self-care experience of stroke survivors and their caregivers is often overlooked in clinical practice. objectives the aim of this study was to explore the dyadic self-care experience of stroke survivors and their caregivers. design a descriptive qualitative design was used to conduct the study. results the consolidated criteria for reporting qualitative research was used for study reporting. a total of 21 stroke survivor-caregiver dyads were recruited for this study between may 2022 and september 2022. data were collected through semistructured interviews and analyzed using thematic analysis. In this study, four themes were identified: (1) poor relationship quality of the dyads, (2) dyadic incongruence in managing stroke, (3) a slow and tiring dyadic self-care process and (4) happy cooperation in coping with dyadic self-care. discussion and conclusion healthcare professionals should give greater consideration to the contradictions and disparities that may arise between stroke survivors and caregivers during the self-care process. It is crucial for them to provide personalized and tailored support and interventions that can assist these individuals in achieving a more optimal balance in their dyadic self-care. patient/public contribution patients were involved in the formulation of interview questions for this study. no members of the public were involved in this study
Diet-induced bacterial immunogens in the gastrointestinal tract of dairy cows: Impacts on immunity and metabolism
Dairy cows are often fed high grain diets to meet the energy demand for high milk production or simply due to a lack of forages at times. As a result, ruminal acidosis, especially subacute ruminal acidosis (SARA), occurs frequently in practical dairy production. When SARA occurs, bacterial endotoxin (or lipopolysaccharide, LPS) is released in the rumen and the large intestine in a large amount. Many other bacterial immunogens may also be released in the digestive tract following feeding dairy cows diets containing high proportions of grain. LPS can be translocated into the bloodstream across the epithelium of the digestive tract, especially the lower tract, due to possible alterations of permeability and injuries of the epithelial tissue. As a result, the concentration of blood LPS increases. Immune responses are subsequently caused by circulating LPS, and the systemic effects include increases in concentrations of neutrophils and the acute phase proteins such as serum amyloid-A (SAA), haptoglobin (Hp), LPS binding protein (LBP), and C-reactive protein (CRP) in blood. Entry of LPS into blood can also result in metabolic alterations. Blood glucose and nonesterified fatty acid concentrations are enhanced accompanying an increase of blood LPS after increasing the amount of grain in the diet, which adversely affects feed intake of dairy cows. As the proportions of grain in the diet increase, patterns of plasma β-hydoxybutyric acid, cholesterol, and minerals (Ca, Fe, and Zn) are also perturbed. The bacterial immunogens can also lead to reduced supply of nutrients for synthesis of milk components and depressed functions of the epithelial cells in the mammary gland. The immune responses and metabolic alterations caused by circulating bacterial immunogens will exert an effect on milk production. It has been demonstrated that increases in concentrations of ruminal LPS and plasma acute phase proteins (CRP, SAA, and LBP) are associated with declines in milk fat content, milk fat yield, 3.5% fat-corrected milk yield, as well as milk energy efficiency
Engineered pine endophytic Bacillus toyonensis with nematocidal and colonization abilities for pine wilt disease control
IntroductionThe pinewood nematode (PWN) is responsible for causing pine wilt disease (PWD), which has led to the significant decline of conifer species in Eurasian forests and has become a globally invasive quarantine pest. Manipulating plant-associated microbes to control nematodes is an important strategy for sustainable pest management. However, it has proven difficult to find pine-associated bacteria that possess both nematocidal activity and the ability to colonize pine tissues.MethodsThe stress experiments with turpentine and pine tissue extract were carried out to screen for the desired target strain that could adapt to the internal environment of pine trees. This strain was used to construct an engineered nematocidal strain. Additionally, a fluorescent strain was constructed to determine its dispersal ability in Pinus massoniana seedlings through plate separation, PCR detection, and fluorescence microscopy observations. The engineered nematocidal strain was tested in the greenhouse experiment to assess its ability to effectively protect P. massoniana seedlings from nematode infection.ResultsThis study isolated a Bacillus toyonensis strain Bxy19 from the healthy pine stem, which showed exceptional tolerance in stress experiments. An engineered nematocidal strain Bxy19P3C6 was constructed, which expressed the Cry6Aa crystal protein and exhibited nematocidal activity. The fluorescent strain Bxy19GFP was also constructed and used to test its dispersal ability. It was observed to enter the needles of the seedlings through the stomata and colonize the vascular bundle after being sprayed on the seedlings. The strain was observed to colonize and spread in the tracheid after being injected into the stems. The strain could colonize the seedlings and persist for at least 50 days. Furthermore, the greenhouse experiments indicated that both spraying and injecting the engineered strain Bxy19P3C6 had considerable efficacy against nematode infection.DiscussionThe evidence of the colonization ability and persistence of the strain in pine advances our understanding of the control and prediction of the colonization of exogenously delivered bacteria in pines. This study provides a promising approach for manipulating plant-associated bacteria and using Bt protein to control nematodes
Grade classification of neuroepithelial tumors using high-resolution magic-angle spinning proton nuclear magnetic resonance spectroscopy and pattern recognition
A retrospective comparative study on the diagnostic efficacy and the complications: between CassiII rotational core biopsy and core needle biopsy
Accurate pathologic diagnosis and molecular classification of breast mass biopsy tissue is important for determining individualized therapy for (neo)adjuvant systemic therapies for invasive breast cancer. The CassiII rotational core biopsy system is a novel biopsy technique with a guide needle and a “stick-freeze” technology. The comprehensive assessments including the concordance rates of diagnosis and biomarker status between CassiII and core needle biopsy were evaluated in this study. Estrogen receptor (ER), progesterone receptor (PgR), human epidermal growth factor receptor 2 (HER2), and Ki67 were analyzed through immunohistochemistry. In total, 655 patients with breast cancer who underwent surgery after biopsy at Sir Run Run Shaw Hospital between January 2019 to December 2021 were evaluated. The concordance rates (CRs) of malignant surgical specimens with CassiII needle biopsy was significantly high compared with core needle biopsy. Moreover, CassiII needle biopsy had about 20% improvement in sensitivity and about 5% improvement in positive predictive value compared to Core needle biopsy. The characteristics including age and tumor size were identified the risk factors for pathological inconsistencies with core needle biopsies. However, CassiII needle biopsy was associated with tumor diameter only. The CRs of ER, PgR, HER2, and Ki67 using Cassi needle were 98.08% (kappa, 0.941; p<.001), 90.77% (kappa, 0.812; p<.001), 69.62% (kappa, 0.482; p<.001), and 86.92% (kappa, 0.552; p<.001), respectively. Post-biopsy complications with CassiII needle biopsy were also collected. The complications of CassiII needle biopsy including chest stuffiness, pain and subcutaneous ecchymosis are not rare. The underlying mechanism of subcutaneous congestion or hematoma after CassiII needle biopsy might be the larger needle diameter and the effect of temperature on coagulation function. In summary, CassiII needle biopsy is age-independent and has a better accuracy than CNB for distinguishing carcinoma in situ and invasive carcinoma
Climate change impacts on US agriculture and forestry: benefits of global climate stabilization
Increasing atmospheric carbon dioxide levels, higher temperatures, altered precipitation patterns, and other climate change impacts have already begun to affect US agriculture and forestry, with impacts expected to become more substantial in the future. There have been numerous studies of climate change impacts on agriculture or forestry, but relatively little research examining the long-term net impacts of a stabilization scenario relative to a case with unabated climate change. We provide an analysis of the potential benefits of global climate change mitigation for US agriculture and forestry through 2100, accounting for landowner decisions regarding land use, crop mix, and management practices. The analytic approach involves a combination of climate models, a crop process model (EPIC), a dynamic vegetation model used for forests (MC1), and an economic model of the US forestry and agricultural sector (FASOM-GHG). We find substantial impacts on productivity, commodity markets, and consumer and producer welfare for the stabilization scenario relative to unabated climate change, though the magnitude and direction of impacts vary across regions and commodities. Although there is variability in welfare impacts across climate simulations, we find positive net benefits from stabilization in all cases, with cumulative impacts ranging from 54.5 billion over the period 2015–2100. Our estimates contribute to the literature on potential benefits of GHG mitigation and can help inform policy decisions weighing alternative mitigation and adaptation actions.United States. Environmental Protection Agency. Climate Change Division (Contract EP-BPA-12-H-0023, Call Order EP-B13H-00143
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