Diffusive and Ballistic Transport in Ultra-thin InSb Nanowire Devices Using a Few-layer-Graphene-AlOx Gate

Quantum devices based on InSb nanowires (NWs) are a prime candidate system for realizing and exploring topologically-protected quantum states and for electrically-controlled spin-based qubits. The influence of disorder on achieving reliable topological regimes has been studied theoretically, highlighting the importance of optimizing both growth and nanofabrication. In this work we investigate both aspects. We developed InSb nanowires with ultra-thin diameters, as well as a new gating approach, involving few-layer graphene (FLG) and Atomic Layer Deposition (ALD)-grown AlOx. Low-temperature electronic transport measurements of these devices reveal conductance plateaus and Fabry-P\'erot interference, evidencing phase-coherent transport in the regime of few quantum modes. The approaches developed in this work could help mitigate the role of material and fabrication-induced disorder in semiconductor-based quantum devices.Comment: 14 pages, 5 figure

Endometrial apoptosis and neutrophil infiltration during menstruation exhibits spatial and temporal dynamics that are recapitulated in a mouse model.

Abstract Menstruation is characterised by synchronous shedding and restoration of tissue integrity. An in vivo model of menstruation is required to investigate mechanisms responsible for regulation of menstrual physiology and to investigate common pathologies such as heavy menstrual bleeding (HMB). We hypothesised that our mouse model of simulated menstruation would recapitulate the spatial and temporal changes in the inflammatory microenvironment of human menses. Three regulatory events were investigated: cell death (apoptosis), neutrophil influx and cytokine/chemokine expression. Well-characterised endometrial tissues from women were compared with uteri from a mouse model (tissue recovered 0, 4, 8, 24 and 48 h after removal of a progesterone-secreting pellet). Immunohistochemistry for cleaved caspase-3 (CC3) revealed significantly increased staining in human endometrium from late secretory and menstrual phases. In mice, CC3 was significantly increased at 8 and 24 h post-progesterone-withdrawal. Elastase+ human neutrophils were maximal during menstruation; Ly6G+ mouse neutrophils were maximal at 24 h. Human endometrial and mouse uterine cytokine/chemokine mRNA concentrations were significantly increased during menstrual phase and 24 h post-progesterone-withdrawal respectively. Data from dated human samples revealed time-dependent changes in endometrial apoptosis preceding neutrophil influx and cytokine/chemokine induction during active menstruation. These dynamic changes were recapitulated in the mouse model of menstruation, validating its use in menstrual research

Event-related potential studies of post-traumatic stress disorder: a critical review and synthesis

Despite the sparseness of the currently available data, there is accumulating evidence of information processing impairment in post-traumatic stress disorder (PTSD). Studies of event-related potentials (ERPs) are the main tool in real time examination of information processing. In this paper, we sought to critically review the ERP evidence of information processing abnormalities in patients with PTSD. We also examined the evidence supporting the existence of a relationship between ERP abnormalities and symptom profiles or severity in PTSD patients. An extensive Medline search was performed. Keywords included PTSD or post-traumatic stress disorder, electrophysiology or EEG, electrophysiology, P50, P100, N100, P2, P200, P3, P300, sensory gating, CNV (contingent negative variation) and MMN (mismatch negativity). We limited the review to ERP adult human studies with control groups which were reported in the English language. After applying our inclusion-exclusion review criteria, 36 studies were included. Subjects exposed to wide ranges of military and civilian traumas were studied in these reports. Presented stimuli were both auditory and visual. The most widely studied components included P300, P50 gating, N100 and P200. Most of the studies reported increased P300 response to trauma-related stimuli in PTSD patients. A smaller group of studies reported dampening of responses or no change in responses to trauma-related and/or unrelated stimuli. P50 studies were strongly suggestive of impaired gating in patients with PTSD. In conclusion, the majority of reports support evidence of information processing abnormalities in patients with PTSD diagnosis. The predominance of evidence suggests presence of mid-latency and late ERP components differences in PTSD patients in comparison to healthy controls. Heterogeneity of assessment methods used contributes to difficulties in reaching firm conclusions regarding the nature of these differences. We suggest that future ERP-PTSD studies utilize standardized assessment scales that provide detailed information regarding the symptom clusters and the degree of symptom severity. This would allow assessment of electrophysiological indices-clinical symptoms relationships. Based on the available data, we suggest that ERP abnormalities in PTSD are possibly affected by the level of illness severity. If supported by future research, ERP studies may be used for both initial assessment and treatment follow-up

Emotional reaction to diagnosis of infertility in Kuwait and successful clients' perception of nurses' role during treatment

<p>Abstract</p> <p>Background</p> <p>The unfulfilled desire of millions of infertile couples worldwide to have their own biological children results in emotional distress. This study evaluated the emotional reactions of couples attending a combined infertility clinic in Kuwait and successful clients' perception of nurses.</p> <p>Methods</p> <p>Quantitative and qualitative methods were used. The first phase was by structured interview using two standardized psychological scales: the 25-item Hopkins Symptom Checklist and Modified Fertility Adjustment Scale. Data were collected from 268 couples attending the combined infertility clinic, between October 2002 and September 2007. The second phase was a semi-structured interview of 10 clients who got pregnant following treatment. The interview explored their feelings and perception of the nurses' role. Interviews were transcribed verbatim and analyzed.</p> <p>Results</p> <p>The average duration of infertility was 4 years; 65.7% of the women and 76.1% of men suffered from primary infertility. Emotional reactions experienced were: anxiety in women (12.7%) and men (6%), depression in women (5.2%) and men (14.9%) and reduced libido in women (6.7%) and men (29.9%). Also in men, 14.9% experienced premature ejaculation, 5.2% weak ejaculation and 7.9% had impotence although 4.9% were transient. In the semi-structured interviews, the emotions expressed were similar and in addition to anger, feelings of devastation, powerlessness, sense of failure and frustration. In the survey, 12.7% of the men were found to show more anxiety than women (6%). Although all the 10 women interviewed confirmed they were anxious; only 4 of their partners were reported to be sad or anxious. Successful clients' perception of nurses' roles included nurses carrying out basic nursing procedures, communicating, educating about investigative and treatment procedures, providing emotional support by listening, encouraging, reassuring and being empathetic.</p> <p>Conclusions</p> <p>This study illuminates the emotional reactions of infertile clients. Fertility nurses in Kuwait can provide emotional support through communication. The need for additional and continuous training for nurses employed in fertility settings in Kuwait is paramount.</p

In Situ Patrolling of Regulatory T Cells Is Essential for Protecting Autoimmune Exocrinopathy

BACKGROUND: Migration of T cells, including regulatory T (Treg) cells, into the secondary lymph organs is critically controlled by chemokines and adhesion molecules. However, the mechanisms by which Treg cells regulate organ-specific autoimmunity via these molecules remain unclear. Although we previously reported autoimmune exocrinopathy resembling Sjögren's syndrome (SS) in the lacrimal and salivary glands from C-C chemokine receptor 7 (CCR7)-deficient mice, it is still unclear whether CCR7 signaling might specifically affect the dynamics and functions of Treg cells in vivo. We therefore investigated the cellular mechanism for suppressive function of Treg cells via CCR7 in autoimmunity using mouse models and human samples. METHODS AND FINDINGS: Patrolling Treg cells were detected in the exocrine organs such as lacrimal and salivary glands from normal mice that tend to be targets for autoimmunity while the Treg cells were almost undetectable in the exocrine glands of CCR7(-/-) mice. In addition, we found the significantly increased retention of CD4(+)CD25(+)Foxp3(+) Treg cells in the lymph nodes of CCR7(-/-) mice with aging. Although Treg cell egress requires sphingosine 1-phosphate (S1P), chemotactic function to S1P of CCR7-/- Treg cells was impaired compared with that of WT Treg cells. Moreover, the in vivo suppression activity was remarkably diminished in CCR7(-/-) Treg cells in the model where Treg cells were co-transferred with CCR7(-/-) CD25(-)CD4(+) T cells into Rag2(-/-) mice. Finally, confocal analysis showed that CCR7(+)Treg cells were detectable in normal salivary glands while the number of CCR7(+)Treg cells was extremely decreased in the tissues from patients with Sjögren's syndrome. CONCLUSIONS: These results indicate that CCR7 essentially governs the patrolling functions of Treg cells by controlling the traffic to the exocrine organs for protecting autoimmunity. Characterization of this cellular mechanism could have clinical implications by supporting development of new diagnosis or treatments for the organ-specific autoimmune diseases such as Sjögren's syndrome and clarifying how the local immune system regulates autoimmunity

Ocean current patterns drive the worldwide colonization of eelgrass (Zostera marina)

publishedVersio

A feasibility study exploring the role of pre-operative assessment when examining the mechanism of ‘chemo-brain’ in breast cancer patients

Background: Women receiving chemotherapy treatment for breast cancer may experience problems with their memory and attention (cognition), which is distressing and interferes with quality of life. It is unclear what causes or contributes to the problems they report: psychological distress, fatigue, coping style, or specific biological changes for example to pro inflammatory cytokines. Research shows however, that approximately a third of women with breast cancer perform poorly on tests of cognition before commencing chemotherapy. We aimed to examine the acceptability and relevance of pre-surgical assessments (bloods, brain imaging, cognitive tests and self-report questionnaires) when investigating the phenomenon of ‘chemo-brain’ and investigate whether inflammatory markers mediate chemotherapy-induced neuropsychological impairments in women treated for breast cancer. Methods: Women with early stage breast cancer completed neuropsychological and quality of life assessments at T1 (pre-surgery), T2 (post-surgery before chemotherapy) and T3 (6 months later). Blood cytokine levels were measured at the same time points and brain imaging was performed at T1 and T3. Results: In total, 14/58 women participated (8 chemotherapy, 6 non-chemotherapy). Prior to the start of chemotherapy a decline in cognitive performance compared to baseline was observed in one participant. At T3 women who received chemotherapy reported poorer quality of life and greater fatigue. Increases in soluble tumour necrosis factor receptor II (sTNFRII), interleukin-6, interleukin-10 and vascular endothelial growth factor occurred post chemotherapy only. Levels of sTNFRII were inversely correlated with grey matter volume (GMV) of the right posterior insula in both groups. At T3, the chemotherapy group displayed a greater reduction in GMV in the subgenual and dorsal anterior cingulate, and the inferior temporal gyrus. Conclusions: Pre-operative recruitment to the study was challenging; however, the lack of significant changes in blood cytokine levels and neuropsychological tests at T2 implies that post surgery may be a valid baseline assessment, but this needs further investigation in a larger study. The preliminary results support the hypothesis that chemotherapy induced fatigue is mediated by a change in peripheral cytokine levels which could explain some symptoms of ‘chemo brain’ experienced by patients