Adjusting surface coverage of Pt nanocatalyst decoration for selectivity control in CMOS-integrated SnO2 thin film gas sensors.

Smart gas-sensor devices are of crucial importance for emerging consumer electronics and Internet-of-Things (IoT) applications, in particular for indoor and outdoor air quality monitoring (e.g., CO2 levels) or for detecting pollutants harmful for human health. Chemoresistive nanosensors based on metal-oxide semiconductors are among the most promising technologies due to their high sensitivity and suitability for scalable low-cost fabrication of miniaturised devices. However, poor selectivity between different target analytes restrains this technology from broader applicability. This is commonly addressed by chemical functionalisation of the sensor surface via catalytic nanoparticles. Yet, while the latter led to significant advances in gas selectivity, nanocatalyst decoration with precise size and coverage control remains challenging. Here, we present CMOS-integrated gas sensors based on tin oxide (SnO2) films deposited by spray pyrolysis technology, which were functionalised with platinum (Pt) nanocatalysts. We deposited size-selected Pt nanoparticles (narrow size distribution around 3 nm) by magnetron-sputtering inert-gas condensation, a technique which enables straightforward surface coverage control. The resulting impact on SnO2 sensor properties for CO and volatile organic compound (VOC) detection via functionalisation was investigated. We identified an upper threshold for nanoparticle deposition time above which increased surface coverage did not result in further CO or VOC sensitivity enhancement. Most importantly, we demonstrate a method to adjust the selectivity between these target gases by simply adjusting the Pt nanoparticle deposition time. Using a simple computational model for nanocatalyst coverage resulting from random gas-phase deposition, we support our findings and discuss the effects of nanoparticle coalescence as well as inter-particle distances on sensor functionalisation.

Probes to measure kinetic and magnetic phenomena in plasmas.

Diagnostic tools are of fundamental importance in experimental research. In plasma physics, probes are usually used to obtain the plasma parameters, such as density, temperature, electromagnetic fields, and waves. This Review focuses on low-temperature plasma diagnostics where in situ probes can be used. Examples of in situ and remote diagnostics will be shown, proven by many experimental verifications. This Review starts with Langmuir probes and then continues with other diagnostics such as waves, beams, and particle collectors, which can provide high accuracy. A basic energy analyzer has been advanced to measure distribution functions with three-dimensional velocity resolution, three directions in real space and time resolution. The measurement of the seven-dimensional distribution function is the basis for understanding kinetic phenomena in plasma physics. Non-Maxwellian distributions have been measured in magnetic reconnection experiments, scattering of beams, wakes of ion beams, etc. The next advance deals with the diagnostics of electromagnetic effects. It requires magnetic probes that simultaneously resolve three field components, measured in three spatial directions and with time resolution. Such multi-variable data unambiguously yield field topologies and related derivatives. Examples will be shown for low frequency whistler modes, which are force-free vortices, flux ropes, and helical phase rotations. Thus, with advanced probes, large data acquisition and fast processing further advance in the fields of kinetic plasma physics and electromagnetic phenomena can be expected. The transition from probes to antennas will also be stimulated. Basic research with new tools will also lead to new applications.

Long-term efficacy of radon spa therapy in rheumatoid arthritis--a randomized, sham-controlled study and follow-up.

OBJECTIVE: To quantify the efficacy of a series of baths containing natural radon and carbon dioxide (1.3 kBq/l, 1.6 g carbon dioxide/l on average) versus artificial carbon dioxide baths alone in patients with rheumatoid arthritis. SUBJECTS: Sixty patients participating in an in-patient rehabilitation programme including a series of 15 baths were randomly assigned to two groups. DESIGN: Pain intensity (100 mm visual analogue scale) and functional restrictions [Keitel functional test, Arthritis Impact Measurement Scales (AIMS questionnaire)] were measured at baseline, after completion of treatment and 3 and 6 months thereafter. To investigate whether the overall value of the outcomes was the same in both groups, the overall mean was analysed by Student's t-test for independent samples. RESULTS: The two groups showed a similar baseline situation. After completion of treatment, relevant clinical improvements were observed in both groups, with no notable group differences. However, the follow-up revealed sustained effects in the radon arm, and a return to baseline levels in the sham arm. After 6 months, marked between-group differences were found for both end-points (pain intensity: -16.9%, 95% confidence interval -27.6 to -6.2%; AIMS score: 0.57, 95% confidence interval 0.16 to 0.98). The between-group differences were statistically significant for both overall means (pain intensity, P: = 0.04; AIMS, P: = 0.01). CONCLUSION: Marked short-term improvements in both groups at the end of treatment may have masked potential specific therapeutic effects of radon baths. However, after 6 months of follow-up the effects were lasting only in patients of the radon arm. This suggests that this component of the rehabilitative intervention can induce beneficial long-term effects.

Profiles of four women. Health and human rights activists.

This article briefly profiles four women physicians working for health and human rights around the world. Dr. Ruchama Marton, an Israeli psychiatrist and activist for peace in the Middle East, is a founder of Physicians for Human Rights/Israel. Dr. Jane Green Schaller is a US pediatrician whose 1985 trip to South Africa initiated her human rights involvement, which includes the founding of Physicians for Human Rights. Dr. Judith van Heerden, a primary care physician in South Africa, has worked for reform of prison health care, to establish hospice care, and, most recently, for acquired immune deficiency syndrome (AIDS) education for medical students. Dr. Ma Thida, the only physician not interviewed for this article, is currently held in a Burmese prison because of her work on behalf of the National League for Democracy. The profiles suggest the breadth of human rights work worldwide and are a testament to what physicians can do.

Health Care Linkage Project: improving access to care.

The primary objective of the Health Care Linkage Project, funded by a grant from the Chicago Community Trust, is to develop, implement, and evaluate a primary health care linkage network within the city of Chicago that creates formalized linkages between community health centers, the Chicago Department of Health clinics, and hospitals. Six linkage networks are currently operational, with an additional two sites phased in during 1991. The success of the pilot project has been demonstrated by hundreds of patients receiving primary care and ancillary services on a more timely basis, by greater coordination between the public and private sector, by cost-savings to both patients and providers through reducing inappropriate use of services, and by a variety of spin-off projects which have improved the quality and accessibility of services. A second important objective is the development of a Health Care Linkage Manual that describes the practical experience and lessons gained from the linkages, the status of comparable arrangements in other U.S. cities, replicability of the linkage models, and recommendations for policy changes which will make linkages more effective.

Autoimmune response following vasectomy.

PIP: 10 men aged 30-48 were studied for autoimmune responses following bilateral vasectomy. During a period of up to 24 months lymphocytotoxic antibodies (LCA) against panels of normal lymphocytes developed in 6 men and against a panel of leukemia cells in 7. A few of the men also developed marked increases of antinuclear (ANA) and antismooth muscle (ASMA) antibodies. The surgical control cases showed no rise of LCA activity within a postoperative period of up to 1 year; the sera of 2/10 healthy hospital employees revealed an incidence of LCA activity similar to that reported in normal populations. The study showed that 60-70% of the vasectomized men developed LCA; an incidence similar to the 50-60% incidence reported with respect to sperm-agglutinating antibodies. Vasectomy in rats, mice, and guinea pigs elicited an antisperm antibody response in some strains but not in others. Apart from incidence there were also variations in the intensity of immune reaction, not only relative to LCA but also relative to antibody titers of ANA and ASMA. Since the immunologic and morphologic changes were observed only in a portion of those who were vasectomized and since the reactions varied in incidence and intensity among the subjects, it is suggested that immune response genes may be operative in the postvasectomy responses.^ieng

Ultrastructure of lipoma.

Eleven benign lipogenic tumors comprising ten ordinary lipomas and one fibroblastic lipoma were studied by light and electron microscopy. The former, which contained only a few inconspicuous septa, were composed of univacuolar mature adipocytes. No young forms of adipocytic differentiation were seen reflecting the slow growth of the ordinary lipomas. Small spindle cells accompanying capillaries located in the triangular confluence of the adipocytes are thought to be potential precursors of adipocytes. By contrast, the fibroblastic lipoma contained many younger forms which closely resembled those seen during maturation of normal adipose tissue. These younger forms are located in and about prominent trabeculae which therefore are considered to constitute active growth centers.

Ultrastructural "fingerprint" in cryoprecipitate and glomerular deposits: a case report of systemic lupus erythematosus.

A 20 year old woman had lupus nephritis and cryoglobulinemia. The cryoglobulins isolated from the serum and a renal biopsy specimen were studied by means of immunofluorescence, immunochemistry, and electron microscopy. Ultrastructural "fingerprint" structures were observed both in the cryoprecipitate and in the glomerular deposits, as were IgG, IgM, and IgA. These observations furnish morphologic evidence for the glomerular deposition of cryoglobulins in lupus nephritis.

Immunofluorescence of renal lesions in paraffin-embedded and fresh-frozen sections.

Immunofluorescent findings in formalin-fixed and paraffin-embedded sections of kidneys involved by various nephropathies compared favorably with those in fresh-frozen sections. In some cases, the findings in paraffin-embedded sections were complementary. Immunoreactivity with complement could not be demonstrated.

Syphilitic lymphadenitis: immunofluorescent identification of spirochetes from imprints.

We are reporting two cases of early syphilis with inguinal buboes which were surgically excised. Th clinical impression was lymphoma in one case and inguinal hernia in the other. The correct and specific diagnosis was quickly established by the application of fluorescent antibody technique to imprints of the enlarged lymph node.

Immunological observations following vasectomy.

Lymphocytotoxic antibodies (LCA) against panels of normal lymphocytes and leukemic B-cells were demonstrated in vasectomized men. Since vasectomy is known to induce antibody formation to spermatozoa, the demonstration of these lymphocytotoxic antibodies may be related to antigenic constituents of spermatozoa such as HLA or B-cell alloantigens. Long term follow-up is needed to clarify the clinical significance of these antibodies.

PIP: Immunological observations were conducted on a study group of 10 men, aged 30-48 years who had bilateral vasectomy under general anesthesia and age-matched controls comprising male patients who underwent minor surgical procedures and healthy male employees of the hospital. Blood samples were drawn before the vasectomy and at selected intervals following vasectomy for a period of up to 24 months. Blood samples were similarly drawn from the control sample. Sera of the vasectomized men and of the control subjects were tested for lymphocytotoxic antibodies (LCA) using a panel of freshly prepared lymphocytes from 40 healthy donors by the microdroplet method of Tarasaki and McClelland. The sera of 6 of the 10 vasectomized men showed a significant increase of LCA activity against the 40-donor-panel of normal lymphocytes. This increase was noted at between 2 and 6 months after vasectomy, and it decreased or even disappeared during the remainder of the 2 years studied. As tested against leukemic B-cells, LCA activity was demonstrated from 1-13 months after vasectomy in all but 1 of the 10 cases. The reaction against the cultured B-cell lines was weak in 2 of the 10 study subjects. There was no reaction in any of the vasectomized men against B-cells from 11 normal donors. Only the sera of the men who underwent vasectomy exhibited any appreciable levels of LCA. The development of LCA against normal lymphocytes in post-vasectomized subjects has been observed previously and seems to be a transient response to vasectomy. The LCA activity demonstrated may be related to retention of spermatozoa and resorption of the antigenic contituents of spermatozoa.

Immunoblastic sarcoma following Waldenström's macroglobulinemia.

Immunoblastic sarcoma has been observed in association with, or subsequent to, chronic immune stimulation, connective tissue disorders, and immunoblastic lymphadenopathy. A case of Waldenström's macroglobulinemia progressinng after a few years into immunoblastic sarcoma is reported. Splenectomy led to disappearance of hemolytic anemia and of pulmonary infiltrates, as well as to marked reduction of macroglobulins. Although immunoblastic sarcoma usually terminates fatally within two or three months, complete remission was induced by combination chemotherapy. It is speculated that Waldenström's macroglobulinemia, immunoblastic lymphadenopathy, and immunoblastic sarcoma are related disorders reflecting a clonal nature of immunoblastic lymphoma cells and the plasmacytic cells.

Spondylothoracic dysostosis: report of two cases and review of the literature.

Two Puerto Rican infants, offsprings of nonconsanguineous parents, died with spondylothoracic dysostosis as characterized by widespread anomalies of the spine (malformed vertebral bodies including hemivertebrae), deformity of the thorax, and fan-like configuration of the ribs. The disease was lethal in early life in the 18 cases previously reported. An autosomal-recessive inheritance has been described. Spondylocostal dysostosis, a related entity, showed associated intrinsic anomalies of the ribs. The 17 cases culled from the literature pursued a milder course, affected mainly older children and adults, and had a different pattern of inheritance.

Brunnian adenoma (inverted papilloma) of the urinary bladder: report of a case.

An additional case of a benign polypoid tumor of the urinary bladder is reported, the first one observed at autopsy and the first in which photographic documentation of the gross appearance is presented. The lesion was first described as an adenomatoid polyp in 1927. We consider the subsequent (1963) designation of inverted papilloma misleading. Because its histologic morphology bears a striking resemblance to Brunn's nests and because the term papilloma of the urinary bladder connotes potential malignant change, we propose the designation brunnian adenoma. All cases previously reported have been benign.

Enterovenous fistulization in Crohn's disease.

A case of Crohn's disease was complicated by enterovenous fistulization (ileum to superior mesenteric vein) with septic manifestations. The fistulization was diagnosed by the observation of gas in the liver and by the opacification of mesenteric veins following a barium meal.

On the relationship between heart weights, fibrosis, and QRS duration.

This study analyzed the effects of heart weights, myocardial fibrosis, sex, and body length upon the duration of the QRS complex. A positive correlation was found between presence or absence of fibrosis and duration of the QRS complex. A positive correlation was also found between weights of the heart and QRS duration, but this correlation appeared to be spurious and due to the tendency of fibrosed hearts to be heavier than those with normal myocardium.