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We report the synthesis and characterization of phase pure Ta3Sb, a material predicted to be topological with eightfold degenerate fermionic states [Science 353, aaf5037 (2016)] and to exhibit a large spin Hall effect [Sci. Adv. 5, eaav8575 (2019]. We observe superconductivity in Ta3Sb with Tc~ 0.67 K in both electrical resistivity \r{ho}(T) and specific heat C(T) measurements. Field dependent measurements yield the superconducting phase diagram with an upper critical field of Hc2(0) ~ 0.95 T, corresponding to a superconducting coherence length of {\xi} ~18.6 nm. The gap ratio deduced from specific heat anomaly, 2{\Delta}0/kBTc is 3.46, a value close to the Bardeen-Cooper-Schrieffer (BCS) value of 3.53. From a detailed analysis of both the transport and thermodynamic data within the Ginsburg-Landau (GL) framework, a GL parameter of \k{appa} ~90 is obtained identifying Ta3Sb as an extreme type-II superconductor. The observation of superconductivity in an eightfold degenerate fermionic compound with topological surface states and predicted large spin Hall conductance positions Ta3Sb as an appealing platform to further explore exotic quantum states in multifold degenerate systems., Comment: 16 Pages, 3 figures

Foot and mouth disease (FMD) is one of the most contagious diseases of mammals and can cause severe economic loss. The Food and Agriculture Organization of the United Nations, Office Internatioal des Epizooties and Pan-American Health Organization have had extensive programmes for FMD surveillance and control. The efforts of these organizations focus on disease reporting, disease status evaluation, safety of world trade, diagnosis and research, standardisation of FMD vaccine production, coordinated control of outbreaks (eg: in Europe in the 90’s) and international support of national and regional FMD control programmes. The coordinated activities of these organizations have contributed greatly to eradication or control of FMD in many countries, and have facilitated global trade while minimising the risk of the introduction of the virus from infected to disease free zones.

The Office International des Epizooties (OIE) has developed international standards to reduce the risk of the spread of high-pathogenicity avian influenza though international trade. These standards include providing a definition of high-pathogenicity avian influenza (HPAI), procedures for prompt reporting of HPAI outbreaks, requirements that must be met for a country or zone to be defined as free of HPAI, requirements that should be met to import live birds and avian products into a HPAI-free country or zone, and the general provisions that countries should meet to reduce the risk of spread of HPAI through trade. The goal of these standards is to facilitate trade while minimizing the risk of the introduction of HPAI.

Covalently immobilized pore-surface gel phases were prepared in a functionalized macroporous ultra-high-molecular-weight polyethylene by covalent coupling of lightly cross-linked polymer colloid particles [50% styrene, 49.8% (chloromethyl)stryrene, 0.2% divinylbenzene] to the interstitial pore surfaces. Swelling the covalently coupled colloid particles in a good solvent followed by chemical derivitization resulted in an immobilized pore-surface gel phase rich in primary amine groups. The macromolecular reactivity and molecular size-exclusion characteristics of the aminated pore-surface gel phase were then determined using monofunctional, amine-reactive, poly (ethylene glycol)s (PEG). Pegylated pore-surface gel phases that ranged from 71% (10,000 molecular weight PEG) to 56% (40,000 molecular weight PEG) PEG by weight resulted from reaction of the aminated gel phase with the PEG probe molecules. The number of PEG molecules reacting with the aminated pore-surface gel phase depends only on the Flory radius (or radius of gyration) of the PEG molecule to the negative 2.49th power i.e., 1/Rf2.49, corresponding to a M−1.48 dependence. The immobilized and pegylated polymer colloid particles swell by a factor of 16–25 times the diameter of the original polymer colloid particles in water, thereby demonstrating that pegylation occurred though a substantial fraction of the volume of the immobilized colloid particles.

We report synthesis and characterization of a macroporous polymeric material containing a covalently immobilized pore-surface phase of well-defined thickness, gel-phase porosity and organic functional group content. The pore surfaces of otherwise inert macroporous (32 μm mean pore size) ultrahigh-molecular-weight polyethylene (UHMWPE) are aminated throughout using a low-pressure flowing-discharge process to enable covalent immobilization of lightly cross-linked polymer colloid particles on all pore surfaces in the monolith. Solvent swelling and chemical derivitization of the covalently immobilized polymer colloid particles produce a pore-surface gel phase of well-defined thickness, organic amine content, and gel-phase porosity. The low degree of cross-linking in the polymer colloid particles prevents dissolution of the immobilized colloid in good solvents and enables the formation of pore-surface gel phases having high gel porosity on swelling in good solvents. The pore-surface amination introduced by the flowing discharge process varies by less than 17% through 5-mm thickness of the macroporous UHMWPE material. The properties of the pore-surface gel phase also vary by less than 17% through the cross section. The pore-surface immobilized polymer colloid particles swell by a factor of 10 in water and tetrahydrofuran after derivitization with polyethylene glycol.

During the summer of 1986, more than 400 California gulls (Larus californicus) and ring-billed gulls (Larvus delawarensis), primarily fledglings, died on an island in Lake Sakakawea near New Town, North Dakota (USA). Mortality was attributed largely to chlamydiosis. Necropsy findings in nine carcasses included splenomegaly (n = 9), hepatomegaly (n = 4), and pericarditis (n = 1). Livers from three California gulls and two ring-billed gulls, and spleens from the same five birds plus a third ring-billed gull were positive for Chlamydia psittaci by the direct immunofluorescence test. Chlamydia psittaci was isolated from separate pools of liver and spleen from one California gull and one ring-billed gull. This is believed to be the first record of epizootic chlamydiosis in gulls and the second report of epizootic chlamydial mortality in wild birds in North America.

Risk of cancer may be slightly increased, but extra screening is not necessary The first report linking cancer with scleroderma (Scl) was 50 years ago when a case of alveolar cell carcinoma was described.1 Since then there have been several further case reports and series linking Scl with cancer at various sites.2 The sites of cancer most frequently reported are the lung3,4 and breast5 (perhaps reflecting their prevalence in the general population), but cancers at other sites have also been reported.2,6 In this issue of the Annals there is a report of an Australian population study on Scl and cancer.7 The authors showed a doubling in the risk of all cancers over an average six year follow up period, with the lung being the site at greatest risk. It is thus timely to consider all the evidence suggesting this association is real and then explore some of the possible underlying explanations. It is necessary to compare the incidence of cancer occurring in patients with Scl with that occurring in an appropriately matched general population sample, typically derived from regional or national cancer registers. Studies, such as the current report from Australia, are enhanced when they attempt to include all cases arising in a population to minimise the likelihood of a severity bias. Table 1 summarises the results of a number of such main population studies. In these studies the risk of cancer is expressed as standardised incidence ratios (SIRs) …

Using ballistic-electron-emission spectroscopy (BEES), we directly determined the energy barrier for electron injection at clean interfaces of Alq(3) with Al and Fe to be 2.1 and 2.2 eV, respectively. We quantitatively modeled the sub-barrier BEES spectra with an accumulated space charge layer, and found that the transport of nonballistic electrons is consistent with random hopping over the injection barrier.

Preventing the spread of disease through international trade is one of the primary objectives of the Office International des Epizooties (OIE), the World Organisation for Animal Health. This is accomplished by establishing international standards that facilitate trade while minimising the risk of introducing diseases such as bluetongue (BT). The OIE standards for BT are contained in the Terrestrial animal health code (Code) and the Manual of diagnostic tests and vaccines for terrestrial animals (Manual). These standards include procedures for prompt reporting of BT outbreaks; requirements that should be met for a country or zone to be defined as free of bluetongue virus (BTV); recommendations for the safe importation of live animals, semen and embryos into a BTV-free country or zone; and the general provisions that countries should meet to reduce the risk of spread of BTV through trade. The Manual describes in detail the various tests for the diagnosis of BT. It provides a list of prescribed tests; these are the tests that are required by the Code for the testing of animals in connection with international trade. There are 24 serotypes of BTV and infected countries have the right to restrict imports from countries that have different types of BTV. However, this should only be done if a surveillance and monitoring programme has confirmed that the other types are not present. Zoning for an arbovirus is difficult to apply but zoning for vectors is practicable. Some countries have demonstrated that there is no evidence of infection in their country or parts of their country even though there has been unrestricted animal movement between endemic zones and free zones. This freedom is due to the absence of vectors in the free zone. Based on this observation, free countries and zones can be established if an appropriate surveillance and monitoring programme is in place to define their boundaries. Consequently, there have been extensive changes in the Code to allow the establishment of BTV-free countries and zones and seasonally free countries and zones to provide the basis for safe trade, while minimising the risk of the introduction of BTV.

Bluetongue virus (BTV) distribution in the United States of America (USA) is limited by the range of the vector Culicoides spp. Regional differences exist with the north-eastern states being free of BTV, while the central and north-western states are seasonally free of virus. Activity of the virus can be observed throughout the year in the southern USA. Serological evidence defining the distribution of BTV in selected regions of the USA is gathered regularly through serological surveys conducted on samples from slaughter cattle. From 1991 to 2002, ten serological surveys were completed. Results from Alaska, Hawaii, Michigan, Minnesota, New York, Wisconsin and New England consistently demonstrated a seropositive rate of less than 2%, confirming BTV-free status. Antibody against BTV was sporadically detected in cattle originating from states contiguous to the BTV-free regions. Additional information on BTV distribution in the USA is obtained through identification of BTV or BTV RNA in diagnostic, surveillance and export specimens submitted to the National Veterinary Services Laboratories. Results confirm that BTV serotypes 2, 10, 11, 13 and 17 are present in the USA.

The performance of 2 competitive enzyme-linked immunosorbent assays (C-ELISA) was compared with the reference C-ELISA I for the detection of antibodies to bluetongue virus (BTV). One of the assays (C-ELISA II) used a group-specific monoclonal antibody (MAb) to BTV, obtained from the American Type Culture Collection (8A3B-6) and tissue culture (TC)-derived BTV antigen (Ag), and the other assay (C-ELISA III) used BTV core protein VP7 (expressed in yeast) and the reference MAb (Pirbright Laboratory, 3–17-A3). Test sera were obtained by sequential blood samples from 22 calves, each inoculated with a different serotype (T) of BTV (South African [SA] T-1-T-16 and T-18-T-20 and USA T-11, T-13, and T-1 7). Sera were also obtained from 4 calves and 4 sheep inoculated with USA BTV T-10 and from several groups of calves exposed to single or multiple doses of epizootic hemorrhagic disease virus (EHDV) T-1-T-4 grown in TC (BHK-21) or suckling mouse brain (SMB). A total of 618 bovine and ovine field sera collected from BT-free and BT-endemic areas were also tested. The C-ELISA III was more sensitive than the C-ELISA II in the detection of anti-BTV antibody in sera from cattle and sheep early after infection with BTV. Seroconversion was demonstrated by the 3 C-ELISAs in all animals inoculated with BTV by 20 days postinfection (DPI), except in calves that received SA T-3 or USA T-13, which became positive at 40 DPI. Unlike with the immunodiffusion test, reaction was not generally seen between BTV TC-derived or VP7 antigens and sera from calves exposed to a single dose of EHDV T-1, T-2, T-3, or T-4 or from calves that received TC-derived EHDV T-1 or T-2 initially and were then challenged with the heterologous EHDVs. Postchallenge samples from calves inoculated and challenged with SMB-derived EHDV T-2 and T-1, respectively, resulted in false reactions in all the C-ELISAs. Relative to the reference C-ELISA I results, the C-ELISA II and C-ELISA III results for the field sera demonstrated lower levels of agreement for bovine samples (97.8% and 96.5%, respectively) than for ovine sera (99.3% and 98.2%, respectively). The overall results suggest that both MAb 8A3B-6 and yeast-expressed VP7 may be suitable as diagnostic reagents in C-ELISA for the detection of anti-BTV group-specific antibodies.

We consider different models of inositol 1,4,5-trisphosphate (IP(3)) receptor (IP(3)R) channels in order to fit nuclear membrane patch clamp data of the stationary open probability, mean open time, and mean close time of channels in the Xenopus oocyte. Our results indicate that rather than to treat the tetrameric IP(3)R as four independent and identical subunits, one should assume sequential binding-unbinding processes of Ca(2+) ions and IP(3) messengers. Our simulations also favor the assumption that a channel opens through a conformational transition from a close state to an active state.

Resonances in the 12C(16O,γ)28Si radiative capture process at energies around the Coulomb barrier have been probed using the very selective 0° Dragon spectrometer at Triumf and its associated BGO γ‐array. For the first time the full level scheme involved in this process has been measured and shows previously unobserved γ‐decay to doorway states around 11 MeV in 28Si.

In a recent experiment performed at Triumf using the Dragon 0° spectrometer and its associated BGO array we have measured for the first time the full gamma decay of the radiative capture channel close to the Coulomb barrier. This measurement has been performed at 3 energies Ecm = 8.5, 8.8 and 9 MeV. We have extracted a radiative capture cross section more than five times larger than what had been previously observed. A selective contribution of the entrance spins 5− and 6+ has also been evidenced whereas 1− to 3− spins are predicted to be predominant by coupled‐channel calculations. At Ecm = 9 MeV, stronger structural behaviour appears which is characterised by a larger total cross section and also by the particularly strong feeding of the 28Si prolate 4+ state at 9.16 MeV. This level is explained by several models in terms of 12C‐16O cluster sub‐structure. Our data is compared to such cluster‐model predictions and the agreement is quite good.

From 1981 to 1989, sera were collected from 3,077 white-tailed deer (Odocoileus virginianus) in Georgia and from 1,749 deer from 12 additional states in the southeastern United States. In Georgia, prevalence of precipitating antibodies to epizootic hemorrhagic disease virus (EHDV) and bluetongue virus (BTV), as determined by agar gel immunodiffusion tests, was dependent on physiographic region, age, and year. Overall prevalence of antibodies to EHDV and/or BTV was 11, 33, 48, and 14% for the Mountain, Piedmont, Coastal Plain, and Barrier Island regions, respectively. Results suggested varying patterns of EHDV and BTV activity throughout the state. Serologic results from other southeastern states were consistent with the Georgia sample; prevalence estimates (EHDV and/or BTV) for corresponding physiographic regions deviated by less than 10%. Over this larger geographical area, antibody prevalence in deer appeared to increase with decreasing latitude.

The International Regulations for transport of infectious substances, including diagnostic specimens, are based on the United Nations Model Regulations and are the standard for transport by all means of transportation including air transport; the International Air Transport Association (IATA) regulation specifically addresses air shipment. In 2005 and 2006 there were major improvements in the procedures for shipping infectious substances. These substances are divided into Category A, which includes primarily cultures of the more pathogenic agents and Category B, all the other substances. Category A shipments must have a Dangerous Goods Certificate and meet other requirements. Category B shipments, which include most diagnostic tissue specimens, do not. These regulations specifically exempt certain substances, including those that have been neutralized or inactivated to destroy pathogens and samples from "normal" animals. The packaging requirements help insure that biocontainment is maintained during shipment to protect the shipper and the environment. The packaging requirements and the shipping procedures provide a chain of custody and assist in supporting biosecurity. The more stringent Category A requirements provide increased biocontainment and biosecurity safeguards for these potentially more dangerous substances. In addition, National requirements, such as import permits and the US select agent requirements, provide an added measure of biocontainment and biosecurity.

The International Regulations for the transport of infectious substances, which could include reagents, reference material and samples, are based on the 13th revision of the United Nations Model Regulations and are the standard for transport of infectious substances by all means of transportation. The 13th revision, effective January 2005 and further amended in March and July 2005, made major improvements in these shipping regulations. They specifically exempt certain substances, including those that have been neutralized or inactivated to destroy any pathogens and samples from "normal" animals. Infectious substances are divided into Category A, which includes primarily cultures of the more pathogenic agents and Category B, which includes all other substances that do not meet the Category A criteria. Tissue specimens, submitted for diagnosis, are included in Category B. Category A shipments must have a Dangerous Goods Certificate and meet other requirements; Category B shipments do not. The National requirements, such as import permits, and certain airline restrictions must also be met.

Epizootic hemorrhagic disease (EHD) of deer is an arthropod-borne Orbivirus that causes infection in wild and domestic ruminants. Infection with EHD virus (EHDV) causes fatal disease, especially in white-tailed deer (Odocoileus virginianus), bighorn sheep (Ovis canadensis), mule deer (Odocoileus hemionus), pronghorn (Antilocapra americana), and possibly black-tailed deer (Odocoileus hemionus columbianus). In domestic ruminants, EHDV may induce clinical and pathologic signs similar to those of bluetongue (BT). However, in North America, natural infections caused by EHDV serotype 1 and serotype 2 have rarely been associated with overt clinical disease in cattle. Laboratory diagnosis is most often based on the detection of anti-EHDV antibodies in serum. Among several serologic assays, agar gel immunodiffusion (AGID) is most widely used but is highly subjective, consumes large quantity of reference reagents, and may be complicated by cross-reactions between EHDV serotypes and other orbiviruses, such as BT viruses (BTVs). As an alternative, enzyme-linked immunosorbent assays (ELISAs), both blocking (bELISA) and competitive (cELISA), have been developed in an attempt to overcome the above problems and to serve as large-scale screening tests with objective interpretation. Recently, a cELISA was developed that utilizes an EHDV group-specific monoclonal antibody (MAb) designated C.31, which is group specific and unreactive with antibodies against BTV. After some modifications, the performance of the this cELISA was compared with that of the standard AGID test for detection of anti-EHDV antibodies using bovine field sera collected in Canada (EHD free) and parts of the USA, where EHD is endemic, and deer sera collected in Georgia (USA). Antigen was prepared from baby hamster kidney cells in serum-free medium and infected with plaque-purified EHDV serotype 1, according to a previously described procedure. Sera from serial or paired blood samples from calves experimentally infected and/or challenged with EHDV serotypes 1 and 2, from a calf experimentally infected with BTV serotype 10, and from several calves exposed to South African BTV serotypes 1-16 and 18-20 and the US BTV serotypes 10, 11, 13, and 17 were used to study seroconversion values. 1-5 To establish negative value, 2 panels totalling 1,194

The Peterborough Hospital Human Tissue Bank (PHHTB) and National Blood Service Tissue Services (London and South East Zone) (NBSTS) operate within the U.K. National Health Service (NHS) and have a system in place to retrieve cadaveric tissues for commercial sector research. The collaboration meets the aims of PHHTB and NBSTS and is legal, ethical and safe. This paper presents the results of the first 20 successful retrievals referred from NBSTS to PHHTB. Cadaveric retrieval of tissue for research extends the options for donors and their relatives. The research option is particularly welcomed in cases where clinical retrieval for tissue transplantation is contraindicated. We believe the system is applicable to other centres.

Susceptibility to infection with avian influenza virus (AIV) was studied in pigeons inoculated via oculonasal (Experiment 1) or intravenous (Experiment 2) route. Chickens were included as susceptible hosts in both experiments. Two subtypes each of the highly pathogenic AIV (HPAIV; HP CK/PA H5N2 and HP CK/Australia H7N7) and non-pathogenic AIV (NPAIV; NP CK/PA H5N2 and NP emu/TX H7N1) at a dose of 10(5) embryo infective dose per bird were used as inoculum. The pigeons inoculated with HP CK/PA H5N2 or HP CK/Australia H7N7 remained apparently healthy throughout the 21-day observation period, did not shed viruses on 3, 7, 14, and 21 days postinoculation (DPI), and had no demonstrable levels of antibodies on 21 DPI. On the other hand, 9 of 12 chickens inoculated with the HPAIV died of highly pathogenic avian influenza; the viruses were recovered from their respiratory and intestinal tissues, and the surviving chickens had antibodies to AIV. Regarding responses of pigeons to inoculation with NP CK/PA H5N2 or NP emu/TX H7N1, the pigeons remained clinically healthy throughout the 21-day observation period and did not have detectable levels of antibodies on 21 DPI; only one pigeon yielded the NP emu/TX H7N1 on 3 DPI. The virus was isolated from a tracheal swab and was believed to be the residual inoculum virus. Based on the responses of pigeons to NPAIV and HPAIV, it was concluded that the pigeons were resistant or minimally susceptible to infection with HPAIV or NPAIV.

The deduced amino acid sequence at the hemagglutinin (HA) cleavage site of 76 avian influenza (AI) viruses, subtypes H5 and H7, was determined by reverse transcription-polymerase chain reaction and cycle sequencing techniques to assess pathogenicity. Eighteen of the 76 viruses were isolated in 1993 and 1994 from various sources in the United States. In addition, 34 H5 (4 highly pathogenic [HP] and 30 non-highly pathogenic [non-HP]) and 24 H7 (3 HP and 21 non-HP) repository viruses, isolated between 1927 and 1992, were sequenced and the sequences compared to those in recent isolates. All repository HP H5 and H7 viruses studied had multiple basic amino acids adjacent to the HA cleavage site and most had basic amino acids in excess of the proposed minimum motif B-X-B-R (B = basic amino acids arginine or lysine, X = nonbasic amino acid, R = arginine) that has been associated with high pathogenicity. Of the non-HP viruses studied, 35 of 38 for H5 and 30 of 31 for H7 conformed to the motif B-X-X-R and B-X-R, respectively. Two non-HP H5 viruses had the motif X-X-X-R at the cleavage site and a third had the motif B-X-X-K (K = basic amino acid lysine). One non-HP H7 (A/Pekin robin/CA/30412-5/94) had four basic amino acids (K-R-R-R) adjacent to the cleavage site. Although the Pekin robin isolate did not produce disease in chickens under the conditions of the study it did have the amino acid sequence compatible with that in HP AI viruses and, therefore, is considered potentially HP. This is the first account of an H7 virus that is non-HP in chickens but meets the molecular criterion to be classified as HP.

Seventeen Newcastle disease virus (NDV) isolates obtained from cormorants, turkeys, a pelican, and a gull in Canada and the USA collected in 1975, 1990 and 1992 were analyzed for relatedness by monoclonal antibody profiling. In addition, nucleotide sequence analysis was performed in two areas of the fusion (F) gene for 5 of the isolates. No difference in the antigenicity of these 17 viruses, as determined by monoclonal antibody binding patterns, was seen. The amino acid sequences obtained via nucleotide sequencing at the cleavage site of the F protein showed that all the isolates tested had two pairs of basic amino acids immediately upstream of the cleavage site, and a phenylalanine residue at the N-terminus of the F1 protein, which is consistent with velogenic NDV. The deduced amino acid sequence obtained at the cleavage site of the F protein from 6 of the isolates was virtually identical regardless of the species, year of isolation, or location. However, the 1975 cormorant isolate showed marked differences from the 1990-1992 isolates in the nucleotide and deduced amino acid sequence of the F gene signal region. These data indicate that the 1990 and 1992 outbreaks were caused by the same epizootic virus and further suggest that the population of NDV in these wild birds may be very stable. The belief that the velogenic NDV circulating in cormorants in 1992 was transmitted into the free-ranging turkey flocks located near the cormorants in North Dakota is supported by the present study in which no distinction could be made between the viruses isolated from turkeys or wild birds.

Epizootic hemorrhagic disease virus (EHDV), an arthropod-borne double-stranded (ds) RNA virus, is a member of the genus Orbivirus in the family Reoviridae. EHDV infects domestic, captive, and free-ranging ruminants; the whitetailed deer (Odocoileus virginianus) is the species most seriously affected with the disease. The association of EHDV with clinical hemorrhagic disease in cattle is rare. In a previous study, experimental EHDV infection in calves resulted in transient infection that could be detected by virus isolation and serological tests. However, few studies have shown that the virus can also cause bluetongue (BT)-like disease in cattle. 20,21 There are 10 serotypes of EHDV worldwide, 13 but only serotypes 1 and 2 are enzootic in the United States. 17,26,27 Recent epidemiological studies of the disease indicated that EHDV-2 was more prevalent than EHDV-1. Even in the absence of the disease, there is restriction on the international movement of livestock and/or their germplasm from countries suspected to harbor the disease to EHDVfree countries unless the animals are certified free of EHDV infection by serology or virus isolation. Such a restriction could lead to economic losses for EHDV-endemic countries that rely on the sale of livestock and their germplasms for foreign exchange. EHDV isolation procedures presently lack adequate sensitivity. Identification of EHDV field isolates includes direct isolation of the virus in baby hamster kidney (BHK-21) cells or initial inoculation of embryonating chicken eggs (ECE), followed by subsequent passages on cell culture for serotyping. 4,6 Serum neutralization and plaque inhibition tests are commonly used for EHDV serotype-specific identification. However, serology is complicated by cross-reactions within EHDV serogroups and among non-EHDV orbiviruses. The surge of new techniques in cell immunology and molecular biology has made possible the development of improved diagnostic tests. A previous report described a competitive enzyme-linked immunosorbent assay (cELISA) protocol for detection of antibodies to EHDV. However, the cELISA technique required collection of blood samples from animals that have been infected for at least 2 weeks to detect EHDV antibody. cDNA probes were also developed for detection of EHDV serogroup-specific and serotype-specific sequences to serve as efficient alternatives for serotyping. 22,23,30,32 However, these cDNA probes have not proven

We compared our recently reported reverse transcriptase polymerase chain reaction (PCR)-based assay for detection of epizootic hemorrhagic disease virus (EHDV) in clinical samples with different virus isolation (VI) procedures. Thirty-six blood samples and 1 spleen sample from deer were assessed by the EHDV PCR assay and VI in baby hamster kidney (BHK)-21 cells and embryonated chicken eggs (ECE). The EHDV PCR assay detected EHDV RNA from 6 blood samples obtained from deer during 1988–1989 outbreaks of epizootic hemorrhagic disease and from the spleen and blood samples of a deer with clinical hemorrhagic disease in 1992. The 6 blood samples from the 1988–1989 outbreaks and the spleen sample from the 1992 case were VI positive on BHK-21 cell culture. The blood from the same deer with the PCR- and VI-positive spleen was VI negative in BHK-21 cells and ECE. All EHDV isolates were identified as EHDV serotype 2 by a plaque inhibition test. The results of this study indicate that the sensitivity of the previously described EHDV PCR assay is comparable to or greater than that of the VI method in BHK-21 cell culture or ECE. The EHDV PCR assays could provide a superior diagnostic alternative to the current cumbersome and time-consuming VI procedures.

Avian influenza virus (AIV) subtypes H5N2 and H7N1 were isolated from emus (Dromaius novaehollandiae) and rheas (Rhea americana) in Texas and North Carolina. All the rheas and emus had a history of respiratory disease except one emu, which was clinically normal. The isolates were not pathogenic for chickens and turkeys under the conditions of the experiment. Humoral antibodies to all known hemagglutinin (H) subtypes except H10, H13, and H14 and to all nine neuraminidase (N) subtypes were found in emus and rheas in 11 states. Therefore, emus and rheas are susceptible to infection with several AIV subtypes.

Clinical signs and lesions can sometimes provide the basis for a presumptive diagnosis of hog cholera (HC). However, an accurate diagnosis requires laboratory testing. The usual procedure for the detection of viral antigen is the examination of cryostat sections stained with fluorescein-conjugated HC antiserum. A more definitive technique is isolation of the virus in PK-15 cell cultures and identification of the viral antigen in cells using an HC fluorescent antibody conjugate. As bovine viral diarrhea (BVD) virus will cross-react with HC virus, isolation must be confirmed by the comparison of BVD and HC staining or, preferably, by the use of monoclonal antibodies that can differentiate between HC and BVD viruses. Hog cholera surveillance must rely on serology. The fluorescent antibody virus neutralization (FAVN) test is the classical technique, and HC and BVD antibody can usually be differentiated if HC-positive serum samples are tested against both viruses. Recently the enzyme-linked immunosorbent assay (ELISA) and peroxidase-labeled antibody tests have become the commonly used techniques.

From 1981 through 1989, serum samples from 855 white-tailed deer (Odocoileus virginianus) from Ossabaw Island, Georgia (USA), were tested for antibodies to bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV). During this period, prevalence of precipitating antibodies to BTV and EHDV as determined by agar gel immunodiffusion (AGID) tests decreased from 74% to 3% and from 34% to 1%, respectively. Antibodies were detected in serum samples from 0.5-yr-old deer only during 1981, 1982, and 1983, and with few exceptions, positive serological results after 1983 were restricted to older age classes. A decrease in prevalence of precipitating antibodies to BTV and EHDV in age classes exposed during 1981 indicates that AGID results from white-tailed deer populations underestimate the extent of previous exposure to these viruses. Serum neutralization test results from AGID-positive deer indicated that BTV 11 was the principal serotype responsible for infections during 1981. Since 1983, this serotype has been replaced by BTV 13; however, there has been a low level of transmission within the herd. Infection with EHDV 2 appeared most prevalent during 1982; as with BTV 13, there has been limited transmission in this high density deer population since 1983.

A renal allograft recipient developed symptoms suggestive of AIDS. Serological studies revealed that the donor was positive for human immunodeficiency virus (HIV). Retrospective testing of stored sequential serum samples showed that the recipient was negative for HIV pretransplant; anti-p24 and anti-p41 antibodies appeared 10 and 49 days posttransplant, respectively. The recipient's serum beta 2-microglobulin levels were elevated 14 days posttransplant, with normal renal function, 35 days before the detection of anti-p24 antibody. p24 Antigen was detected for the first time 21 days posttransplant. In addition to p24 antigen, elevated serum beta 2-microglobulins may be a useful marker for HIV infection prior to seroconversion.

The deduced amino acid sequence at the hemagglutinin (HA) cleavage site of 76 avian influenza (AI) viruses, subtypes H5 and H7, was determined by reverse transcription-polymerase chain reaction and cycle sequencing techniques to assess pathogenicity. Eighteen of the 76 viruses were isolated in 1993 and 1994 from various sources in the United States. In addition, 34 H5 (4 highly pathogenic [HP] and 30 non-highly pathogenic [non-HP]) and 24 H7 (3 HP and 21 non-HP) repository viruses, isolated between 1927 and 1992, were sequenced and the sequences compared to those in recent isolates. All repository HP H5 and H7 viruses studied had multiple basic amino acids adjacent to the HA cleavage site and most had basic amino acids in excess of the proposed minimum motif B-X-B-R (B = basic amino acids arginine or lysine, X = nonbasic amino acid, R = arginine) that has been associated with high pathogenicity. Of the non-HP viruses studied, 35 of 38 for H5 and 30 of 31 for H7 conformed to the motif B-X-X-R and B-X-R, respectively. Two non-HP H5 viruses had the motif X-X-X-R at the cleavage site and a third had the motif B-X-X-K (K = basic amino acid lysine). One non-HP H7 (A/Pekin robin/CA/30412-5/94) had four basic amino acids (K-R-R-R) adjacent to the cleavage site. Although the Pekin robin isolate did not produce disease in chickens under the conditions of the study it did have the amino acid sequence compatible with that in HP AI viruses and, therefore, is considered potentially HP. This is the first account of an H7 virus that is non-HP in chickens but meets the molecular criterion to be classified as HP.

Avian influenza virus (AIV) subtypes H5N2 and H7N1 were isolated from emus (Dromaius novaehollandiae) and rheas (Rhea americana) in Texas and North Carolina. All the rheas and emus had a history of respiratory disease except one emu, which was clinically normal. The isolates were not pathogenic for chickens and turkeys under the conditions of the experiment. Humoral antibodies to all known hemagglutinin (H) subtypes except H10, H13, and H14 and to all nine neuraminidase (N) subtypes were found in emus and rheas in 11 states. Therefore, emus and rheas are susceptible to infection with several AIV subtypes.

In 1991, velogenic viscerotropic Newcastle disease (VVND) was diagnosed in domestic psittacine birds in six states: Illinois, Indiana, Michigan, Texas, California, and Nevada. In the first four states, the disease assumed outbreak proportions. The affected psittacine birds--yellow-headed Amazon parrots (Amazona ochrocephala oratrix), yellow-naped Amazon parrots (Amazona ochrocephala auropalliata), cockatiels (Nymphicus hollandicus), and conures (unknown species)--exhibited respiratory and/or central nervous system signs. The velogenic viscerotropic Newcastle disease virus (VVNDV) was isolated from cloacal and tracheal swabs and various tissues, such as the lung, trachea, distal intestine, and spleen. The origin of the birds could not be established. The disease in the six states was promptly controlled, with no evidence that domestic poultry had been exposed. Also, VVNDV was isolated from quarantined birds intended for importation into the United States. Included were 53 moustached parakeets (Psittacula alexandri fasciata), a mynah (Gracula religiosa), a drongo (Dicrurus sp.), and three partridges (family Phasianidae). Groups of birds that yielded VVNDV were denied entry into the United States. Birds that are illegally imported and therefore not tested for the presence of foreign animal pathogens are a potential source of VVNDV and a threat to domestic poultry and caged birds.

SUMMARYAn Asian patient with undiagnosed typhoid fever was admitted to a maternity hospital and delivered within 10 mm. Salmonella typhi (phage type D5) was isolated from her blood and from the faeces of her baby. Another woman in a different room of the labour suite at the same time acquired the same organism in her faeces; her brother was admitted to the Infectious Diseases Unit 5 weeks later with typhoid fever. Two babies, born over 60 h after the index case was delivered, became faecal excreters of the same strain and one of them also developed S. typhi osteitis of the hip. These two babies and their mothers were in the same ward as each other, but not that occupied by the infected mother and her baby. Nine other excreters in two of the families involved were identified. The index case and her baby were isolated immediately after delivery, and the relevant rooms in the labour suite were adequately disinfected. No evidence of undisinfected equipment used by the index case and the other infected patients was found, and no spread to staff was detected. The mode of spread remains unknown.

Velogenie viscerotropic Newcastle disease (VVND) virus was transmitted by Fannia canicularis (L.) that had been fed either on the virus introduced into the feeding bottles of the flies or on moribund chickens infected with VVND. Fannia caniciilaris fed on a concentrated virus source retained infectivity for at least 6 days before being frozen. In vitro infectivity of even single Hies was demonstrated. Fannia canicularis therefore should be regarded as one agent involved in the spread of VVND.

The x-ray spectrum emitted from a tritided erbium film as a result of the beta decay is used to determine areal density and tritium content of the film. A Si (Li) detector and a dedicated minicomputer are used for detection, acquisition, and data reduction. The technique is suitable for areal densities of erbium from 0.01 mg/cm2 to as high as 10 mg/cm2. The occluded tritium can be measured from less than one to several hundred microliters. Precision is generally determined by counting errors and is typically less than 1% for a 5-min count while accuracy depends upon the empirical calibration technique.

Pheasants (Phasianus colchicus) and chukars (Alectoris graeca) were inoculated with Venezuelan equine encephalitis virus. Antibody titers reached a peak 2 weeks postinoculation and then declined. Viremia was of short duration, clinical signs were not detected, and uninoculated cage mates did not develop antibody titers.

Fresnel diffraction by circular apertures for beams commonly encountered in high‐power laser systems is investigated. Striking agreement is demonstrated between experimental results and theoretical calculations for beams with uniform and Gaussian intensity profiles. It is pointed out that Fresnel diffraction patterns produced by circular apertures depend only on the incident wave front and the Fresnel number corrected for curvature of the incident beam, F = a2/λL + a2/λR. This also gives an excellent experimental method for measuring divergence. Methods are discussed for minimizing the occurrence of severe intensity variations and resulting self‐focusing problems in high‐power laser amplifiers.