Operando neutron diffraction reveals mechanisms for controlled strain evolution in 3D printing

Residual stresses affect the performance and reliability of most manufactured goods and are prevalent in casting, welding, and additive manufacturing (AM, 3D printing). Residual stresses are associated with plastic strain gradients accrued due to transient thermal stress. Complex thermal conditions in AM produce similarly complex residual stress patterns. However, measuring real-time effects of processing on stress evolution is not possible with conventional techniques. Here we use operando neutron diffraction to characterize transient phase transformations and lattice strain evolution during AM of a low-temperature transformation steel. Combining diffraction, infrared and simulation data reveals that elastic and plastic strain distributions are controlled by motion of the face-centered cubic and body-centered cubic phase boundary. Our results provide a new pathway to design residual stress states and property distributions within additively manufactured components. These findings will enable control of residual stress distributions for advantages such as improved fatigue life or resistance to stress-corrosion cracking.

Entropic comparison of Landau-Zener and Demkov interactions in the phase space of a quadrupole billiard

We investigate two types of avoided crossings in a chaotic billiard within the framework of information theory. The Shannon entropy in the phase space for the Landau-Zener interaction increases as the center of the avoided crossing is approached, whereas for the Demkov interaction, the Shannon entropy decreases as the center of avoided crossing is passed by with an increase in the deformation parameter. This feature can provide a new indicator for scar formation. In addition, it is found that the Fisher information of the Landau-Zener interaction is significantly larger than that of the Demkov interaction.

[Concept of lateral lymph nodes in rectal cancer and controversy over lateral lymph node dissection]

Lateral lymph node (LLN) metastasis in locally advanced rectal cancer (LARC) is associated with patient prognosis. However, the role of lateral lymph node dissection (LLND) remains controversial. The concept of LLN and the exact definition of LLND have been inconsistently reported in the literatures. The treatment strategy for LARC has differed between the East and the West. The Japanese doctors advocates total mesorectal excision (TME) with LLND for LARC, but less neoadjuvant radiochemotherapy (NARC). European and Americans prefer NARC plus TME, and do not recommend LLND. So far, only the Japanese Statute of Colorectal Cancer has a clear definition of the concept of LLN and LLND. The use of TME plus LLND for LARC is not supported by high level evidences. In today's high-speed development of minimally invasive surgery, the proper selection of standardized surgical methods for LARC requires the joint efforts of scholars from the East and the West to conduct multicenter high-grade clinical trials to select the best treatment option for patients with LARC.

Lipid nanoparticle formulations for optimal RNA-based topical delivery to murine airways

INTRODUCTION

Lipid nanoparticles (LNP) have been successfully used as a platform technology for delivering nucleic acids to the liver. To broaden the application of LNPs in targeting non-hepatic tissues, we developed LNP-based RNA therapies (siRNA or mRNA) for the respiratory tract. Such optimized LNP systems could offer an early treatment strategy for viral respiratory tract infections such as COVID-19.

METHODS

We generated a small library of six LNP formulations with varying helper lipid compositions and characterized their hydrodynamic diameter, size distribution and cargo entrapment properties. Next, we screened these LNP formulations for particle uptake and evaluated their potential for transfecting mRNA encoding green fluorescence protein (GFP) or SARS-CoV2 nucleocapsid-GFP fusion reporter gene in a human airway epithelial cell line in vitro. Following LNP-siGFP delivery, GFP protein knockdown efficiency was assessed by flow cytometry to determine %GFP+ cells and median fluorescence intensity (MFI) for GFP. Finally, lead LNP candidates were validated in Friend leukemia virus B (FVB) male mice via intranasal delivery of an mRNA encoding luciferase, using in vivo bioluminescence imaging.

RESULTS

Dynamic light scattering revealed that all LNP formulations contained particles with an average diameter of <100 nm and a polydispersity index of <0.2. Human airway epithelial cell lines in culture internalized LNPs with differential GFP transfection efficiencies (73-97%). The lead formulation LNP6 entrapping GFP or Nuc-GFP mRNA demonstrated the highest transfection efficiency (97%). Administration of LNP-GFP siRNA resulted in a significant reduction of GFP protein expression. For in vivo studies, intranasal delivery of LNPs containing helper lipids (DSPC, DOPC, ESM or DOPS) with luciferase mRNA showed significant increase in luminescence expression in nasal cavity and lungs by at least 10 times above baseline control.

CONCLUSION

LNP formulations enable the delivery of RNA payloads into human airway epithelial cells, and in the murine respiratory system; they can be delivered to nasal mucosa and lower respiratory tract via intranasal delivery. The composition of helper lipids in LNPs crucially modulates transfection efficiencies in airway epithelia, highlighting their importance in effective delivery of therapeutic products for airways diseases.

First Description of a Helicopter-Borne ECPR Team for Remote Refractory Out-of-Hospital Cardiac Arrest

Introduction: Access time to extracorporeal cardiopulmonary resuscitation (ECPR) refractory out of hospital cardiac arrest (OHCA) is a crucial factor. In our region, some patients are not eligible to this treatment due to the impossibility to reach the hospital with reasonable delay (ideally 60 min). In order to increase accessibility for patients far from ECPR centers, we developed a helicopter-borne ECPR-team which is sent out to the patient for ECPR implementation on the scene of the OHCA.Methods: We conducted a retrospective monocentric study to evaluate this strategy. The team is triggered by the local emergency medical service and heliborne on the site of the OHCA. All consecutive patients implemented with ECPR by our heliborne ECPR team from January 2014 to December 2017 were included. We analyzed usual CA characteristics, different times (no-flow, low-flow, time between OHCA and dispatch…), and patient outcome.Results: During this 4-year study period, 33 patients were included. Mean age was 43.9 years. Mean distance from the ECPR-team base to OHCA location was 41 km. Mean low-flow time was 110 minutes. Five patients survived with good neurological outcome; 6 patients developed brain death and became organ donors.Conclusion: These results show the possibility to make ECPR accessible for patients far from ECPR centers. Survival rate is non negligible, especially in the absence of therapeutic alternative. An earlier trigger of the ECPR-team could reduce the low-flow time and probably increase survival. This strategy improves equity of access to ECPR and needs to be confirmed by further studies.

Correlating work hardening with co-activation of stacking fault strengthening and transformation in a high entropy alloy using in-situ neutron diffraction

Transformation induced plasticity (TRIP) leads to enhancements in ductility in low stacking fault energy (SFE) alloys, however to achieve an unconventional increase in strength simultaneously, there must be barriers to dislocation motion. While stacking faults (SFs) contribute to strengthening by impeding dislocation motion, the contribution of SF strengthening to work hardening during deformation is not well understood; as compared to dislocation slip, twinning induced plasticity (TWIP) and TRIP. Thus, we used in-situ neutron diffraction to correlate SF strengthening to work hardening behavior in a low SFE Fe₄₀Mn₂₀Cr₁₅Co₂₀Si₅ (at%) high entropy alloy, SFE ~ 6.31 mJ m⁻². Cooperative activation of multiple mechanisms was indicated by increases in SF strengthening and γ-f.c.c. → ε-h.c.p. transformation leading to a simultaneous increase in strength and ductility. The present study demonstrates the application of in-situ, neutron or X-ray, diffraction techniques to correlating SF strengthening to work hardening.

Infective endocarditis in patients who use IV drugs: a single centre cohort

Background

Managing endocarditis in intravenous drug use (IVDU) patients is challenging: unless patients successfully quit IVDU, the risk of re-infection is high. Clinicians often raise concerns with ethical and resource allocation principles when considering valve replacement surgery in this patient population. To help inform practice, we sought to determine the long-term outcomes of IVDU patients with endocarditis who underwent valve surgery in our center.

Method

After research ethics board approval, infective endocarditis cases managed surgically at our General Hospital between 2009 and 2018 were identified through the Cardiac Care Network. We reviewed patients' charts and included those with a history of IVDU in this study. We abstracted data on baseline characteristics, peri-operative course, short- and long-term outcomes. We report results using descriptive statistics.

Results

We identified 124 IVDU patients with surgically managed endocarditis. Mean age was 37 years (SD 11), 61% were females and 8% had redo surgery. During admission, 45% (n=56) of the patients had an embolic event: 63% pulmonary, 30% cerebral, 18% peripheral and 11% mesenteric. Causative organisms included Methicillin-Sensitive Staphylococcus Aureus (51%, n=63), Methicillin-Resistant Staphylococcus Aureus (15%, n=19), Streptococcus Viridans (2%, n=2), and others (31%, n=38). Emergency cardiac surgery was performed for 42% of patients (n=52). Most patients (84%) had single valve intervention: 53% tricuspid, 18% aortic and 13% mitral. Double valve interventions occurred in 15% (n=18). Overall, bioprosthetic replacement was most commonly chosen (79%, n=98). In-hospital mortality was 7% (n=8). Median length of stay in hospital was 13 days (IQR 8,21) and ICU 2 days (IQR 1,6). Mortality at longest available follow-up was 24% (n=30), with a median follow-up of 129 days (IQR 15,416). Valve reintervention rate was 11% (n=13) and readmission rate was 14% (n=17) at a median of 275 days (IQR 54,502).

Conclusion

Despite their critical condition, IVDU patients with endocarditis have good intra-hospital outcomes. Challenges occur after hospital discharge with loss of follow-up and high short-term mortality. IVDU relapse likely accounts for some of these issues. In-hospital and community comprehensive addiction management may improve these patients' outcomes beyond the surgical procedure.

Annual rate 2009–2018

Funding Acknowledgement

Type of funding source: None

A high-pressure flow through test vessel for neutron imaging and neutron diffraction-based strain measurement of geological materials

Neutron scattering and neutron imaging have emerged as powerful methods for experimentally investigating material deformation and fluid flow in the interior of otherwise inaccessible or opaque structures. This paper describes the design and provides example uses of a pressure cell developed for investigating such behaviors within geological materials. The cell can accommodate cylindrical samples with diameters up to 38.1 mm and lengths up to 154 mm. Ports in the cell and a pressure isolating sleeve around the sample allow the independent application of confining pressure up to 69 MPa and axial pressure up to 34.5 MPa. Two material versions of the cell have been manufactured and used to date. An aluminum version is typically used for temperatures below 40 °C, because of its relative transparency to neutrons, while a titanium version, which is comparatively more neutron attenuating, is used for experiments requiring triaxial pressurization under conditions up to 350 °C. The pressure cells were commissioned at the VULCAN engineering diffractometer at the Oak Ridge National Laboratory (ORNL), Spallation Neutron Source, and have since been used at the ORNL high flux isotope reactor CG1-D imaging beamline, National Institute of Standard and Technology (NIST) BT-2, and NIST NG6 imaging beamlines.

[Whole lung lavage in an infant with pulmonary alveolar proteinosis and literature review]

Objective: To investigate the safety, feasibility and operation key points of whole lung lavage in infants with pulmonary alveolar proteinosis. Methods: The clinical manifestations, genetic screening, therapeutic interventions and outcome of an infant with pulmonary alveolar proteinosis complicated with respiratory failure who received whole lung lavage in November 2018 in Shanghai Children's Medical Center Affiliated to Shanghai Jiaotong University School of Medicine were reported. Websites including PubMed, Springer Link, China National Knowledge Infrastructure (CNKI), Weipu Database, and Wanfang Database were searched using the key words of "whole lung lavage" "pediatric" and "pulmonary alveolar proteinosis" for articles published from their establishments to April 2019. Relevant literature was reviewed. Results: A 3-month-old boy had experienced cough, shortness of breath and cyanosis for 1 week prior to admission to pediatric intensive care unit. Physical examination showed hepatosplenomegaly. Complete blood cell count showed mild anemia (hemoglobin 96 g/L) and normal white blood cells. The patient had normal C-reactive protein and normal blood platelet. Biochemical panel showed hypoalbuminemia (31 g/L), mildly elevated glutamic oxaloacetic transaminase (115 U/L) and blood ammonia (165 μmol/L), extremely elevated lactate dehydrogenase (>6 600 U/L) and hyperferritinemia (>4 500 μg/L). Chest computed tomography (CT) revealed decreased transmittance of both lungs, patchy high density shadow and ground glass opacity. Genetic testing revealed a mutation of c.625+1G>A in SLC7A7. Schiff reaction (PAS staining) in bronchoalveolar lavage fluid was positive. The patient was diagnosed with severe pneumonia, respiratory failure, lysinuria urinary protein intolerance, and pulmonary alveolar proteinosis. The patient received sequential unilateral whole lung lavage in 2 days and was successfully weaned from ventilator. He was discharged home breathing room air. Eleven articles (11 in English and non in Chinese) were reviewed. Twenty-one patients were included. After whole lung lavage, 76% (16/21) of the patients had improvement in respiratory function. Conclusions: Whole lung lavage can effectively improve respiratory failure caused by pulmonary alveolar proteinosis in infant patients. The procedure is feasible and safe.

[Relationship between expression of high-mobility group box-1 and inflammatory cytokines in patients with bone cancer pain]

Objective: To investigate the change and relationship between serum high-mobility group box-1(HMGB1) and related inflammatory cytokines level in patients suffer with bone metastatic pain. Methods: Collection of the bone cancer pain patients who received analgesic therapy the department of pain in The First Affiliated Hospital of Jiaxing University from November 2016 to August 2016. Serum concentration of HMGB1, the Receptor of Advanced Glycation Endproducts (RAGE), monocyte chemotactic protein-1(MCP-1), tumor necrosis factor -α (TNF-α), interleukin-1β (IL-1β), interleukin-10 (IL-10), interleukin-13 (IL-13), and transforming growth factor-β (TGF-β) levels were determined in 15 healthy individuals as healthy donor and 15 patients with bone metastatic pain by enzyme-linked immunosorbent (ELISA) . The healthy individuals and patients with bone metastatic pain were collected before treatment and on 7 d after the treatment. Results: The serum concentration of HMGB1 and RAGE were significantly increased in tumorous group compared with healthy group[(8.8±2.3) vs (1.9±1.1) μg/L,(231±16) vs (46±20) ng/L); t=7.10,12.44, both P<0.05], then decreased after analgesic therapy [(4.77±1.36) μg/L, (129.80±29.32) ng/L, t=7.10, 12.44, both P<0.05]. The serum concentration of proinflammatory cytokines such as MCP-1, TNF-α, and IL-1β were significantly increased in tumorous group when compared with healthy group, and decreased after analgesic therapy (all P<0.05). The expression of anti-inflammatory cytokines such as IL-10, IL-13, and TGF-β were significantly increased in tumorous group when compared with healthy group, and decreased after analgesic therapy (all P<0.05).Compared with healthy group, the levels of MCP-1/IL-10, MCP-1/IL-13, MCP-1/TGF-β, TNF-α/IL-10, TNF-α/IL-13, TNF-α/TGF-β, IL-1β/IL-10, IL-1β/IL-13, IL-1β/TGF-β were significantly increased in tumorous group (all P<0.05). Conclusion: HMGB1 may adjust the proinflammatory-anti-inflammatory system homeostasis to participate in the development of bone metastatic pain.

A suite-level review of the neutron powder diffraction instruments at Oak Ridge National Laboratory

The suite of neutron powder diffractometers at Oak Ridge National Laboratory (ORNL) utilizes the distinct characteristics of the Spallation Neutron Source and High Flux Isotope Reactor to enable the measurements of powder samples over an unparalleled regime at a single laboratory. Full refinements over large Q ranges, total scattering methods, fast measurements under changing conditions, and a wide array of sample environments are available. This article provides a brief overview of each powder instrument at ORNL and details the complementarity across the suite. Future directions for the powder suite, including upgrades and new instruments, are also discussed.

[Relationship between C-C chemokine receptor type 2 and P38 mitogen-activated protein kinase signaling pathway in the spinal cord of rats with bone cancer pain]

Objective: To investigate the relationship between C-C chemokine receptor type 2(CCR2) and P38 mitogen-activated protein kinase (P38MAPK) signaling pathway in the spinal cord of rats and further clarify the mechanism of bone cancer pain (BCP). Methods: A total of 92 healthy female SD rats, of which 60 were subjected to behavioral tests using a ciliary mechanical stimulation needle. SD rats were randomly divided into six groups: sham operation group (group S), bone cancer pain group (group B), sham operation + DMSO solvent group (group SD), bone cancer pain + DMSO solvent group (group BD), sham operation + RS102895 CCR2 inhibitor group (group SR), bone cancer pain + RS102895 CCR2 inhibitor group (group BR), and Von Frey was used in the behavioral test. Another 32 SD rats were randomly divided into the following 8 groups (n=4): sham operation group (group S), bone cancer pain 5 d group (group B5), bone cancer pain 9 d group (group B9), bone cancer pain 14 d group (group B14), bone cancer pain + DMSO solvent group (group BD), bone cancer pain + RS102895 CCR2 inhibitor 0.5 h group (group BR0.5 h), bone cancer pain + RS102895 CCR2 inhibitor 4 h group (group BR4 h), bone cancer pain + RS102895 CCR2 inhibitor 12 h group (group BR12 h). Western blot was used to detect the expression of P38, p-P38 and CCR2 in spinal cord of rats. Results: At day 5, 7, 9, 14, 21 post-injection, mechanical withdrawal thresholds of group S were(30.9±1.5), (31.9±1.2), (32.0±1.1), (31.6±1.5), (32.2±1.4)g respectively, the mechanical withdrawal thresholds of group B were( 26.4±0.7), (24.4±0.8), (21.4±0.8), (13.5±0.4), (9.9±0.2)g respectively, the mechanical withdrawal thresholds in group B decreased obviously versus group S, and the differences were statistically significant(t=-13.177, -16.660, -23.778, -35.574, -48.401, all P<0.01). At day 9 post-injection, the mechanical withdrawal thresholds in SD, BD, SR and BR groups were (32.4±1.7), (19.4±1.1), (32.1±1.3), (26.3±1.0) g respectively, the difference was statistically significant (F=224.681, P<0.01), and the mechanical withdrawal thresholds in group BD decreased obviously versus group SD, while the mechanical withdrawal thresholds in group BR increased obviously versus group BD. The expression levels of p-P38 in spinal cord of group S, group B5, group B9 and group B14 were(0.08±0.03), (0.20±0.05), (0.40±0.17), (0.65±0.14)respectively, the expression levels of CCR2 were(0.08±0.04), (0.18±0.05), (0.30±0.09), (0.58±0.07)respectively, the difference was statistically significant(F=19.123, 40.746, all P<0.01), and the expression of p-P38 and CCR2 in group B9 were showed a significant up-regulation versus group S. The expression levels of p-P38 in spinal cord of group BD, group BR0.5 h, group BR4 h and group BR12 h were (0.57±0.06), (0.17±0.11), (0.03±0.01), (0.25±0.11)respectively, and the difference was statistically significant(F=29.582, P<0.01). The expression of p-P38 in group BR0.5 h, BR4 h, BR12 h showed a significant down-regulation versus group BD. Conclusion: CCR2 in the spinal cord may be involved in the development of bone cancer pain by activating P38MAPK signaling pathway in rats.

[Prevention and treatment of Horner syndrome in treatment of head and face hyperhidrosis by thoracic sympathetic nerve modulation]

Objective: By summarize the Prevention and Treatment of Horner Syndrome of CT-guided thoracic sympathetic nerve modulation in the treatment of head and face Hyperhidrosis, reduce the occurrence of the complications. Methods: A retrospective analysis was made on 116 patients of CT-guided thoracic sympathetic nerve modulation in the treatment of head and face Hyperhidrosis in The First Hospital of Jiaxing from January 2010 to December 2016. Analysis the reasons of Horner syndrome and external management to sum up the corresponding prevention and treatment measures. Results: Under the guidance of CT positioning, 116 patients were successfully punctured to the intended target (both sides of the R3 above the rib head), after injection of local anesthetic plus contrast agent, CT scan showed there are 39 sides of the liquid parallel to the outside of pleural (26 sides) or over (13 sides) R1 above the rib head. CT scan again after the injection of anhydrous alcohol, there are 43 sides of the liquid parallel to the outside of pleural (24 sides) or over (19 sides) R1above the rib head.After the operation, 22 sides appeared Horner syndrome, 19 of which immediately give physiological saline 5 ml into the ipsilateral Satellite ganglion.Within 2 hours Horner's syndrome completely disappeared, while 3 cases were not treated, Horner syndrome lasts for 3 months to 2 years. Conclusion: The incidence of Horner syndrome relatively high during the CT-guided thoracic sympathetic nerve modulation to treatment of head and face Hyperhidrosis. Injecting 5 ml physiological saline into the ipsilateral Satellite ganglion immediately can completely eliminate this common complications.

Base excess and lactate as prognostic indicators for patients treated by extra corporeal life support after out hospital cardiac arrest due to acute coronary syndrome

OBJECTIVE

To examine whether values of arterial base excess or lactate taken 3 h after starting ECLS indicate poor prognosis and if this can be used as a screening tool to follow Extra Corporeal Life Support after Out Hospital Cardiac Arrest due to acute coronary syndrome.

DESIGN

Single Centre retrospective observational study.

SETTING

University teaching hospital general adult intensive care unit.

PATIENTS

15 consecutive patients admitted to the intensive care unit after refractory Out Hospital Cardiac Arrest due to acute coronary syndrome treated by Extra Corporeal Life Support.

INTERVENTIONS

Arterial base excess and lactate concentrations were measured immediately after starting ECLS and every 3 h after.

RESULTS

Both base excess and arterial lactate measured 3 h after starting ECLS effectively predict multi-organ failure occurrence and mortality in the following 21 h (area under the curve on receiver operating characteristic analysis of 0.97, 0.95 respectively). The best predictive values were obtained with a base excess level measured 3 h after starting ECLS of less than -10 mmol/l and lactate concentrations greater than 12 mmol/l. The combination of these two markers measured 3 h after starting ECLS predicted multiorgan failure occurrence and mortality in the following 21 h with a sensitivity of 70% and a specificity of 100%.

CONCLUSIONS

Combination of base excess and lactate, measured 3 h after starting ECLS, can be used to predict multiorgan failure occurrence and mortality in the following 21 h in patients admitted to an intensive care unit for refractory Out Hospital Cardiac Arrest due to acute coronary syndrome treated by Extra Corporeal Life Support. These parameters can be obtained simply and rapidly and help in the decision process to continue ECLS for refractory CA.

Extracting grain-orientation-dependent data fromin situtime-of-flight neutron diffraction. I. Inverse pole figures

The problem of calculating the inverse pole figure (IPF) is analyzed from the perspective of the application of time-of flight neutron diffraction toin situmonitoring of the thermomechanical behavior of engineering materials. On the basis of a quasi-Monte Carlo (QMC) method, a consistent set of grain orientations is generated and used to compute the weighting factors for IPF normalization. The weighting factors are instrument dependent and were calculated for the engineering materials diffractometer VULCAN (Spallation Neutron Source, Oak Ridge National Laboratory). The QMC method is applied to face-centered cubic structures and can be easily extended to other crystallographic symmetries. Examples include 316LN stainless steelin situloaded in tension at room temperature and an Al–2%Mg alloy, substantially deformed by cold rolling andin situannealed up to 653 K.

Design and implementation of a multiaxial loading capability during heating on an engineering neutron diffractometer

A gripping capability was designed, implemented, and tested for in situ neutron diffraction measurements during multiaxial loading and heating on the VULCAN engineering materials diffractometer at the spallation neutron source at Oak Ridge National Laboratory. The proposed capability allowed for the acquisition of neutron spectra during tension, compression, torsion, and/or complex loading paths at elevated temperatures. The design consisted of age-hardened, Inconel(®) 718 grips with direct attachment to the existing MTS load frame having axial and torsional capacities of 100 kN and 400 N·m, respectively. Internal cooling passages were incorporated into the gripping system for fast cooling rates during high temperature experiments up to ∼1000 K. The specimen mounting couplers combined a threaded and hexed end-connection for ease of sample installation/removal without introducing any unwanted loads. Instrumentation of this capability is documented in this work along with various performance parameters. The gripping system was utilized to investigate deformation in NiTi shape memory alloys under various loading/control modes (e.g., isothermal, isobaric, and cyclic), and preliminary results are presented. The measurements facilitated the quantification of the texture, internal strain, and phase fraction evolution in NiTi shape memory alloys under various loading/control modes.

Competitive Interactions between Immature Stages of Bactrocera cucurbitae (Coquillett) and Bactrocera tau (Walker) (Diptera: Tephritidae) under Laboratory Conditions

The melon fly, Bactrocera cucurbitae (Coquillett), and the pumpkin fly, Bactrocera tau (Walker), are economically important pests that attack mainly cucurbitacean fruits. The two fruit fly species have similar natural distributions, host ranges, and population growth capacities. This study was designed to assess the asymmetrical competitions through resource exploitation between the larvae of B. cucurbitae and B. tau at different density levels and temperatures, and on different hosts by comparing the relative effects of interspecific and intraspecific interactions on four life history parameters: survival rate, puparial mass, puparial duration, and developmental duration. Our results showed that intraspecific and interspecific competitions occurred under some laboratory conditions, and B. cucurbitae took advantage over B. tau at the high-density level and at low and high temperatures on pumpkin, bitter gourd, and bottle gourd when interspecific competition took place. Intraspecific and interspecific competitions mainly affected the puparial mass and the survival rate of the two fruit fly species but had no marked effect on the puparial duration or development duration.

Spinal protein kinase Mζ contributes to the maintenance of peripheral inflammation-primed persistent nociceptive sensitization after plantar incision

BACKGROUND

Previous studies suggest that persistent post-surgical pain (PPSP) is correlated with preoperative pain status and amplification of central sensitization. Protein kinase Mζ (PKMζ) is an essential substrate of the late long-term potentiation underlying central sensitization, which is one mechanism of pain memory formation. However, the potential contributions of spinal PKMζ to PPSP, a condition in which preoperative pain is prevalent, are not known.

METHODS

Here, a modified 'hyperalgesia priming' model was established to simulate the clinical situation. This model used intraplantar injections of carrageenan (Car) as priming stimuli to elicit persistent nociceptive sensitization after plantar incision in rats. Upon treatment with PKMζ inhibitor ZIP, Scr-ZIP or protein kinase Cs (PKCs) inhibitor NPC-15437, altered behaviour and spinal PKMζ/PKCs expression were observed.

RESULTS

A long-lasting hypersensitivity induced by Car-priming was identified and precipitated by subsequent plantar incision in this 'two-hit' paradigm. Post-treatment with ZIP, but not Scr-ZIP and NPC-15437, after the resolution of Car-priming selectively relieved hypersensitivity. In contrast, pre-priming NPC-15437 treatment only prevented Car-induced initial transient hyperalgesia. Immunoassays showed a significant decrease in spinal PKMζ expression after plantar incision with post-priming ZIP treatment as compared with Scr-ZIP and NPC-15437, but no notable differences in PKCs expression were observed.

CONCLUSIONS

Spinal PKCs solely contribute to the initial induction of persistent pain, whereas PKMζ plays an essential role in spinal plasticity storage. PKMζ is responsible for the maintenance of peripheral inflammation-primed PPSP. Therefore, spinal PKMζ may be a therapeutic target to prevent surgery-induced chronic pain in patients with preoperative pain.

Effects of zinc on interleukins and antioxidant enzyme values in psoriasis-induced mice

The effects of zinc chloride (ZnCl2), disodium zinc ethylenediamine tetraacetate (Zn-EDTA), and zinc gluconate (Zn-GLU) on the antioxidant enzyme activities and levels of interleukins (ILs) in psoriasis-induced mice were studied. One hundred twenty female mice were randomly divided into six groups with 20 mice in each group: the control, positive control (PC), methotrexate (MTX), ZnCl2, Zn-EDTA, and Zn-GLU groups. All animals except the control group were given diethylstilbestrol for three consecutive days. After successfully inducing psoriasis, the control and PC groups were given normal saline (i.g.) daily while the remaining groups were given MTX, ZnCl2, Zn-EDTA, and Zn-GLU, respectively. The results revealed that the zinc supplementation could significantly (p < 0.05) inhibit mitosis in the mouse vaginal epithelium as methotrexate did and the inhibiting efficacy had nothing to do with the zinc forms. After ZnCl2, Zn-EDTA, and Zn-GLU supplementation, the levels of liver superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) activities increased and the concentration of malondialdehyde (MDA) decreased significantly (p < 0.05) compared to the PC group. The levels of SOD, CAT activity, and MDA level between each zinc supplementation group and MTX group were insignificant (p > 0.05). The zinc treatments also caused a significant (p < 0.05) decrease in the raised IL-2 level of animal serum. The results obtained in the present work indicate the potential for zinc as a complementary pharmaceutical intervention for the treatment of topical psoriasis.

Spectrum of the cavity-QED microlaser: strong coupling effects in the frequency pulling at off resonance

We report the first experimental observation of the cavity-QED microlaser spectrum, specifically the unconventional frequency pulling brought by a strong atom-cavity coupling at off resonance. The pulling is enhanced quadratically by the atom-cavity coupling to result in a sensitive response to the number of pumping atoms (2.1 kHz per atom maximally). Periodic variation of the pulling due to the coherent Rabi oscillation is also observed as the number of pumping atoms is increased across multiple thresholds.

Strain incompatibility and residual strains in ferroelectric single crystals

Residual strains in ferroelectrics are known to adversely affect the material properties by aggravating crack growth and fatigue degradation. The primary cause for residual strains is strain incompatibility between different microstructural entities. For example, it was shown in polycrystalline ferroelectrics that residual strains are caused due to incompatibility between the electric-field-induced strains in grains with different crystallographic orientations. However, similar characterization of cause-effect in multidomain ferroelectric single crystals is lacking. In this article, we report on the development of plastic residual strains in [111]-oriented domain engineered BaTiO(3) single crystals. These internal strains are created due to strain incompatibility across 90° domain walls between the differently oriented domains. The average residual strains over a large crystal volume measured by in situ neutron diffraction is comparable to previous X-ray measurements of localized strains near domain boundaries, but are an order of magnitude lower than electric-field-induced residual strains in polycrystalline ferroelectrics.

Polarized neutron diffraction at a spallation source for magnetic studies

The availability of high-power spallation neutron sources, along with advances in the development of coupled moderators and neutron polarizers, has made it possible to use polarized neutrons on time-of-flight diffractometers forin situstudies of phenomena contributing to field-induced magnetization of a material. Different electronic and structural phenomena that contribute to the overall magnetization of a material can be studied and clearly identified with polarized neutron diffraction measurements. This article reports the first results from polarized neutron diffraction experiments on a time-of-flight instrument at a spallation source. Magnetic field-induced rotation of electron spins in an Ni–Mn–Ga single crystal was measured with polarized neutron diffraction at the MAGICS reflectometer at the Spallation Neutron Source at Oak Ridge National Laboratory. The difference in intensities measured with spin-up and spin-down polarized neutrons is proportional to the field-induced magnetization of the crystal. The polarized neutron measurements indicate that the magnetic form factor for the 3delectrons of Mn in Ni–Mn–Ga is lower than the value reported earlier for an ideal spherical symmetry of electronic distribution. Future experiments for studying field-induced magnetization in materials following the current methodology are outlined.

Prescribed nondegenerate high-order modes in an axial-asymmetric high-finesse Fabry-Perot microcavity

We report an axial-asymmetric high-Q Fabry-Perot cavity supporting nondegenerate Hermite-Gaussian modes of the same mode order. Axial asymmetry of mirror surface was introduced by mechanically grinding off one side of a cylindrical mirror substrate without degrading the original mirror quality. The bases of the resulting Hermite-Gaussian modes were aligned with respect to the direction of grinding, making it possible to prescribe the mirror principal axes.

Sign reversal of field-angle resolved heat capacity oscillations in a heavy Fermion superconductor CeCoIn5 and d{x{2}-y{2}} pairing symmetry

To identify the superconducting gap symmetry in CeCoIn5 (T{c}=2.3 K), we measured the angle-resolved specific heat (C{phi}) in a field rotated around the c axis down to a very low temperature, 0.05T{c}, and made detailed theoretical calculations. In a field of 1 T, a sign reversal of the fourfold angular oscillation in C{phi} was observed at T approximately 0.1T{c} upon entering a quasiclassical regime where the maximum of C{phi} corresponds to the antinodal direction, coinciding with the angle-resolved density of states (ADOS) calculation. The C{phi} behavior, which exhibits minima along the [110] directions, unambiguously allows us to conclude d{x{2}-y{2}} symmetry of this system. The ADOS-quasiclassical region is confined to a narrow T and H domain within T/T{c} approximately 0.1 and 1.5 T (0.13H{c2}).

[Epidemiology of SARS: mission of the emergency medical department of the French Hospital of Hanoi]

During the epidemic of severe acute respiratory syndrome (SARS) that occurred in Vietnam in March 2003, the French Ministries of Health and Foreign Affairs dispatched a mission composed of personnel from the emergency medical assistance department (French acronym, SAMU) and one virologist from the Pasteur Institute to the French hospital in Hanoi. The purpose of this mission was to reinforce the local medical staff, to bring medical equipment, and to assist in identifying the cause of the SARS epidemic. Most of the 39 cases observed involved health care personnel working at the hospital. Six including 5 who died presented severe manifestations. Application of strict empirical measures of isolation, hygiene, and personal protection allowed containment of the SARS outbreak in Hanoi.

Cavity-damping-induced transitions in a driven atom- cavity system

We investigate the fluorescence spectrum of a two-level atom in a cavity when the atom is driven by a classical field. We show that forbidden dipole transitions in the Jaynes-Cummings ladder structure are induced in the presence of cavity damping, which deteriorates the degree of otherwise perfect destructive interference among the transition channels. With the larger cavity decay, these transitions are more enhanced.

Mechanisms of female urinary continence under stress: frequency spectrum analysis

Intravesical and urethral pressure signals during cough and Valsalva maneuvers for 15 continent women were analyzed with frequency spectrum analysis. Clear modulation of the urethral pressure changes by the intravesical pressure rise during stress maneuvers was demonstrated in the frequency bands of 14 and 7 Hz for cough and Valsalva, respectively. The linearity between the urethral and intravesical pressure signals was strong for cough, but relatively weaker for Valsalva. The observed linearity lead to the formulation of a modified continence equation to mathematically quantify stress leak point pressure (sLPP): sLPP=MUCP/(1-alpha1)+RBP. This algebraic equation demonstrated that sLPP depends on pressure transmission, resting bladder pressure, and maximum urethral closure pressure. The equation was validated with excellent theoretical predictions for the 15 continent subjects (R(2)=0.98 and 0.97 for cough and Valsalva leak point pressure, respectively) and good but somewhat weaker predictions for 46 stress incontinent women (R(2)=0.79 and 0.48, respectively). It has been shown that pressure transmission plays the most important role in female continence function, while it may be attributable to passive structural origin as evidenced by the minimal time delay between the two pressure signals, in the order of a few milliseconds. It can be concluded that coughing seems to have a more mechanical, rather than neuromuscular basis for its signal dynamics. This study suggests that a complete assessment of female stress continence function requires comprehensive urodynamic information in terms of pressure transmission, maximum urethral closure pressure, and resting bladder pressure.

Training-related changes in the maximal rate of torque development and EMG activity

This study monitored the effects of a short-term elbow flexor training program on surface electromyographic (SEMG) spike activity. The experimental paradigm consisted of three test sessions separated by 2-week intervals. At the beginning of each session, participants (N=13) performed five maximal effort isometric contractions of the elbow flexors to serve as baseline. After 5 min of rest, the participants then engaged in a 30-trial isometric fatigue protocol during which maximal elbow flexion torque was measured with a load-cell, and the maximal rate of change in the torque (dtau/dt(max)) was obtained from the differentiated torque-time curve. Bipolar electrodes were used to monitor the SEMG spike activity of the biceps brachii. Mean spike amplitude (MSA) and mean spike frequency (MSF) were calculated for the torque development and constant-torque phases of the isometric contraction, termed Segment 1 and Segment 2, respectively. Mean power frequency (MPF) was also calculated for Segment 2. The five baseline contractions of the second and third sessions were compared with those of the first session and analyzed for training-related changes. Training increased dtau/dt(max) but failed to change maximal elbow flexion torque or MSA. However, there was an increase in the MSF during the torque development phase of the contraction (Segment 1). Both MSA and MSF were greatest during the constant-torque phase of the isometric contraction (Segment 2). There was a strong linear correlation (r=0.90, P<0.05) between MSF and MPF during (Segment 2). We hypothesize that the increase in dtau/dt(max) is due to enhanced motor-unit rate-coding. The demonstrated correlation between MSF and MPF measures will allow investigators to use spike analysis to examine the frequency content of the SEMG signal under non-stationary conditions.

CeReS-18, a cell regulatory sialoglycopeptide, inhibits proliferation and migration of rat vascular smooth muscle cells

CeReS-18, a cell regulatory sialoglycopeptide, has been shown to inhibit proliferation of a wide array of target cells. In the present study, the effect of CeReS-18 on vascular smooth muscle cell (SMC) proliferation was characterized in cultured rat aorta SMCs (A7r5). More extensively, the effect of CeReS-18 on platelet-derived growth factor (PDGF)-induced SMC migration was examined using a modified Boyden's chamber assay. CeReS-18 inhibits both SMC proliferation and migration in a concentration-dependent, calcium-sensitive, and reversible manner. Furthermore, cells preincubated with the inhibitor had an increased sensitivity to CeReS-18-mediated inhibition of SMC migration. Immunoprecipitation and in vitro phosphorylation assays demonstrated that MAP kinase activity was inhibited in the CeReS-18-treated cells and pretreatment with CeReS-18 suppressed the activation of MAP kinase stimulated by PDGF. However, it is not likely that the suppression of the MAP kinase pathway was directly responsible for the ability of CeReS-18 to inhibit migration of the rat aorta smooth muscle cells since a MEK-specific inhibitor, PD98059, did not influence A7r5 cell migration.

Cylindrical microcavity laser based on the evanescent-wave-coupled gain

A microcavity laser based on the gain only in the evanescent field region of whispering gallery modes has been demonstrated. A cylindrical microcavity of 125 microm diam was surrounded by rhodamine 6G dye molecules in an ethanol solution of lower refractive index such that whispering gallery modes of the microcavity underwent laser oscillation when the dye molecules in the evanescent field region outside the cavity were excited by a second harmonic of a Nd:YAG laser. For particular pumping spots, single-mode laser oscillation of a transverse magnetic mode was observed at about 600 nm with associated cavity Q of 3x10(7).

Use of electron microscopic and immunogold labeling techniques to determine polyomavirus recombinant VP1 capsid-like particles entry into mouse 3T6 cell nucleus

Murine polyomavirus major structural protein VP1 could assemble into capsid-like particles when expressed in the baculovirus system. The recombinant capsid-like particles that were purified by CsCl density gradient centrifugation were capable of packaging host DNA. Electron microscopic and immunogold labeling techniques were used to study the entry of these VP1 recombinant capsid-like particles into mouse 3T6 cells. It was found that these VP1 recombinant capsid-like particles, which lack polyomavirus minor structural proteins (VP2 and VP3), use the same mechanism to enter mouse 3T6 cell cytoplasm and nucleus as that used by native polyomavirus virions.

T-DNA insertional mutagenesis for functional genomics in rice

We have produced 22 090 primary transgenic rice plants that carry a T-DNA insertion, which has resulted in 18 358 fertile lines. Genomic DNA gel-blot and PCR analyses have shown that approximately 65% of the population contains more than one copy of the inserted T-DNA. Hygromycin resistance tests revealed that transgenic plants contain an average of 1.4 loci of T-DNA inserts. Therefore, it can be estimated that approximately 25 700 taggings have been generated. The binary vector used in the insertion contained the promoterless beta-glucuronidase (GUS) reporter gene with an intron and multiple splicing donors and acceptors immediately next to the right border. Therefore, this gene trap vector is able to detect a gene fusion between GUS and an endogenous gene, which is tagged by T-DNA. Histochemical GUS assays were carried out in the leaves and roots from 5353 lines, mature flowers from 7026 lines, and developing seeds from 1948 lines. The data revealed that 1.6-2.1% of tested organs were GUS-positive in the tested organs, and that their GUS expression patterns were organ- or tissue-specific or ubiquitous in all parts of the plant. The large population of T-DNA-tagged lines will be useful for identifying insertional mutants in various genes and for discovering new genes in rice.

Murine polyomavirus infection of 3T6 mouse cells shows evidence of predominant necrosis as well as limited apoptosis

The current study was developed to determine if polyomavirus infected 3T6 mouse cells evoked an apoptotic or a necrotic mechanism during infection. Infected cells were analyzed by flow cytometry, transmission electron microscopy (TEM), DNA electrophoresis and by measuring caspase-3 enzymatic activity. Infected cells that were analyzed at 72 h post-infection showed the following: flow cytometry analysis revealed a 5% increase in apoptotic cells and a 46% increase in necrotic cells when compared to uninfected cells; electron microscopy showed 10% cells with characteristic apoptotic morphology and 40% with necrotic appearance; caspase-3 activity was found to increase two fold when compared to uninfected cells and DNA fragmentation (laddering) was clearly evident late in infection. It was concluded that infected cells predominantly showed necrosis, although some cells showed apoptosis in late infection. Recombinant capsid-like particles composed of the polyomavirus structural proteins were not able to induce cell death.

Use of the confocal microscope to determine polyomavirus recombinant capsid-like particle entry into mouse 3T6 cells

The structural protein genes of polyomavirus were expressed in the baculovirus system, and the proteins were found to assemble into capsid-like particles capable of packaging insect cell DNA. Recombinant capsid-like particles could be produced that were composed of the various structural proteins (VP1, VP1/2, VP1/3 and VP1/2 + VP3). Laser scanning confocal microscopy was used to determine if the various capsid-like particles could infect (enter) mouse 3T6 cells. Each of the various capsid-like particles was equally capable of cell entry as determined by indirect immunofluorescence confocal microscopy.

Avian polyomavirus major capsid protein VP1 interacts with the minor capsid proteins and is transported into the cell nucleus but does not assemble into capsid-like particles when expressed in the baculovirus system

The baculovirus system was used to construct and isolate AcMNPV-VP1, AcMNPV-VP2 and AcMNPV-VP3 recombinant viruses which express the respective avian polyomavirus (APV) structural proteins in Sf9 insect cells. These recombinant AcMNPVs containing APV structural protein genes were utilized to investigate protein-protein interactions between the structural proteins. Immunofluorescence studies utilizing Sf9 cells infected with the AcMNPV-VP1 revealed that the VP1 protein was expressed and localized in the cytoplasm and not transported into the nucleus. When the cells were co-infected with the VP1 and either VP2 or VP3 recombinant viruses, immunofluorescence of the VP1 protein was localized in the nucleus, indicating that the VP1 protein was transported to the nucleus by both the VP2 and VP3 minor proteins. This observation was suggestive of a protein-protein interaction between the expressed proteins. This protein-protein interaction was substantiated by laser scanning confocal microscopy of Sf9 cells that were co-infected with VP1, VP2 and VP3 recombinant viruses. However, the minor proteins could not be co-isolated with VP1 protein by immunoaffinity chromatography using a monoclonal anti-VP1 serum. In addition, capsid-like particles could not be purified either by CsC1 density gradient centrifugation or by immunoaffinity chromatography. VP1 capsomeres were isolated by immunoaffinity chromatography from Sf9 cells infected with AcMNPV-VP1, with or without the minor protein(s), and these capsomeres could assemble in vitro into capsid-like particles. Electron microscopic observation of thin-sectioned Sf9 cells, which were co-infected with VP1, VP2 and VP3 recombinant viruses, demonstrated capsomere-like structures in the nucleus, but capsid-like particles were not observed.

Use of the baculovirus system to assemble polyomavirus capsid-like particles with different polyomavirus structural proteins: analysis of the recombinant assembled capsid-like particles

The genes encoding the structural proteins (VP1, VP2 and VP3) of murine polyomavirus were cloned into the p2Bac dual multiple cloning site vector, individually or jointly, and the corresponding proteins were expressed in Spodoptera frugiperda (Sf9) insect cells by cotransfecting Sf9 cells with the constructed vector and the linear DNA of Autographa californica multiple nuclear polyhedrosis virus (AcMNPV). Recombinant capsid-like particles could be purified 5 days post-infection from Sf9 cells infected with AcMNPV-VP1, with or without the involvement of minor protein (VP2 or VP3). Although VP2 and VP3 alone could not generate recombinant particles, they became incorporated into these particles when expressed with VP1 in Sf9 cells. Recombinant particles with different polyomavirus structural protein(s) were obtained by using different combined expression of these proteins in Sf9 cells. Cellular DNA of 5 kbp in size was packaged in all of the recombinant particles, which showed the same diameter as that of native virions. Agarose gel electrophoresis indicated that DNA packaged in these recombinant particles had a different pattern than that of native virions. Two-dimensional gel electrophoresis of the VP1 species of recombinant particles showed more VP1 species than those of the native virions from mouse cells, and an additional species of VP1 when VP2 was co-expressed with VP1. The recombinant particles were also compared for their ability to compete for polyomavirus infection. The competition assay indicated that the recombinant particles containing VP2 were the most efficient in inhibiting the native polyomavirus infection of 3T6 cells.