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Although modern humans left Africa multiple times over 100,000 years ago, those broadly ancestral to non-Africans dispersed less than 100,000 years ago1. Most models hold that these events occurred through green corridors created during humid periods because arid intervals constrained population movements2. Here we report an archaeological site—Shinfa-Metema 1, in the lowlands of northwest Ethiopia, with Youngest Toba Tuff cryptotephra dated to around 74,000 years ago—that provides early and rare evidence of intensive riverine-based foraging aided by the likely adoption of the bow and arrow. The diet included a wide range of terrestrial and aquatic animals. Stable oxygen isotopes from fossil mammal teeth and ostrich eggshell show that the site was occupied during a period of high seasonal aridity. The unusual abundance of fish suggests that capture occurred in the ever smaller and shallower waterholes of a seasonal river during a long dry season, revealing flexible adaptations to challenging climatic conditions during the Middle Stone Age. Adaptive foraging along dry-season waterholes would have transformed seasonal rivers into ‘blue highway’ corridors, potentially facilitating an out-of-Africa dispersal and suggesting that the event was not restricted to times of humid climates. The behavioural flexibility required to survive seasonally arid conditions in general, and the apparent short-term effects of the Toba supereruption in particular were probably key to the most recent dispersal and subsequent worldwide expansion of modern humans.

Depth regulates many attributes of aquatic ecosystems, but relatively few lakes are measured, and existing datasets are biased toward large lakes. To address this, we used a large dataset of maximum (Zmax; n= 16,831) and mean (Zmean; n= 5,881) depth observations to create new depth models, focusing on lakes < 1,000 ha. We then used the models to characterize patterns in lake basin shape and volume. We included terrain metrics, water temperature and reflectance, polygon attributes, and other predictors in a random forest model. Our final models generally outperformed existing models (ZmaxR2=0.35; root mean square error [RMSE] = 8.0 m and ZmeanR2=0.36; RMSE = 3.0 m). Our models show that lake depth followed a Pareto distribution, with 2.8 orders of magnitude fewer lakes for an order of magnitude increase in depth. In addition, despite orders of magnitude variation in surface area, most size classes had a modal maximum depth of ~ 5 m. Concave (bowl‐shaped) lake basins represented 79% of all lakes, but lakes were more convex (funnel‐shaped) as surface area increased. Across the conterminous United States, 9.8% of all lake water was within the top meter of the water column, and 48% in the top 10 m. Excluding the Laurentian Great Lakes, we estimate the total volume in the conterminous United States is 1,057–1,294 km3, depending on whether Zmaxor Zmeanwas modeled. Lake volume also exhibited substantial geographic variation, with high volumes in the upper Midwest, Northeast, and Florida and low volumes in the southwestern United States.

Pancreatic ductal adenocarcinoma is a lethal disease with limited treatment options and poor survival. We studied 83 spatial samples from 31 patients (11 treatment-naïve and 20 treated) using single-cell/nucleus RNA sequencing, bulk-proteogenomics, spatial transcriptomics and cellular imaging. Subpopulations of tumor cells exhibited signatures of proliferation, KRAS signaling, cell stress and epithelial-to-mesenchymal transition. Mapping mutations and copy number events distinguished tumor populations from normal and transitional cells, including acinar-to-ductal metaplasia and pancreatic intraepithelial neoplasia. Pathology-assisted deconvolution of spatial transcriptomic data identified tumor and transitional subpopulations with distinct histological features. We showed coordinated expression of TIGIT in exhausted and regulatory T cells and Nectin in tumor cells. Chemo-resistant samples contain a threefold enrichment of inflammatory cancer-associated fibroblasts that upregulate metallothioneins. Our study reveals a deeper understanding of the intricate substructure of pancreatic ductal adenocarcinoma tumors that could help improve therapy for patients with this disease.

In recent years, many researchers have struggled to obtain carbon dots (CDs) that possess strong photoluminescence in the red region of light. Success in this area has been limited, although the past few years have brought several promising reports on this topic. The most successful efforts in this area still seem to struggle from a lack of dispersibility/reduced emission in water. This work endeavors to understand the formation process of CDs that do not possess strong performance in an aqueous environment and to improve their capabilities in bioimaging. o-Phenylenediamine (o-PDA) is used along with various precursors in several different solvents (varying acidic and oxidative strengths) to understand the formation process behind the structure leading to red emission that is sensitive to water. These results showed that the combination of acid properties and oxidation is essential for this process, and the important reactions are oligomerization of o-PDA and the crosslinking of these oligomers to form aromatic structural segments of CDs. These CDs are shown to be capable of quantitatively detecting water in organic solvents. Additionally, we have shown that conjugation with transferrin remarkably enhances the biocompatibility of these CDs. Transferrin-conjugated CDs with better biocompatibility were applied to bioimaging studies of neuroblastoma cell lines with N-mycand non-N-mycgene amplification, for the first time. Furthermore, CDs showed versatile bioimaging capability toward a highly aggressive neuroblastoma subgroup of tumors. The importance of creating red-emissive CDs has been well established, and this work is an important step toward understanding their formation and realizing their use in biological systems.

Introduction: Subtotal cholecystectomy (SC) is a technique to manage the difficult gallbladder and avoid hazardous dissection and biliary injury. Until recently it was used infrequently. However, because of reduced exposure to open total cholecystectomy in resident training, we recently adopted subtotal cholecystectomy as the bail-out procedure of choice for resident teaching. This study reports our experience and outcomes with subtotal cholecystectomy in the years immediately preceding adoption and since adoption. Methods: A retrospective analysis was conducted of patients undergoing SC from July 2010 to June 2019. Outcomes, including bile leak, reoperation and need for additional procedures, were analyzed. Complications were graded by the Modified Accordion Grading Scale (MAGS). Results: 1571 cholecystectomies were performed of which 71 were SC. Subtotal cholecystectomy patients had several indicators of difficulty including prior attempted cholecystectomy and previous cholecystostomy tube insertion. The most common indication for SC was marked inflammation in the hepatocystic triangle (51%). As our experience increased, fewer patients required open conversion to accomplish SC and SC was completed laparoscopically, usually subtotal fenestrating cholecystectomy (SFC). Most patients (85%) had a drain placed and 28% were discharged with a drain. The highest MAGS complication observed was grade 3 (11 patients, 15%). Six patients had a bile leak from the cystic duct resolved by ERCP. At mean follow-up of about 1 year no patient returned with recurrent symptoms. Conclusions: Subtotal fenestrating cholecystectomy is a useful technique to avoid biliary injury in the difficult gallbladder and can be performed with very satisfactory rates of bile fistula, ERCP, and reoperation.

This work investigates the physicochemical properties of mixed stearic acid (HSt)/phenylalanine dehydrogenase enzyme (PheDH) Langmuir films and their immobilization onto solid supports as Langmuir–Blodgett (LB) films. PheDH from the aqueous subphase enters the surfactant matrix up to an exclusion surface pressure of 25.3 mN/m, leading to the formation of stable and highly condensed mixed Langmuir monolayers. Hydrophobic interactions between the enzyme and HSt nonpolar groups tuned the secondary structure of PheDH, evidenced by the presence of β-sheet structures as demonstrated by infrared and circular dichroism spectra. The floating monolayers were successfully transferred to solid quartz supports, yielding Y-type LB films, and then characterized employing fluorescence, circular dichroism, and microscopic techniques, which indicated that PheDH was co-immobilized with HSt proportionally to the number of transferred layers. The enzyme fluidized the HSt monolayers, reducing their maximum dipoles when condensed to their maximum, and disorganized the alkyl chains of the fatty acid, as detected with infrared spectroscopy. The stability of the mixed floating monolayers enabled their transfer to solid supports as LB films, which is important for producing optical and electrochemical sensors for phenylalanine whose molecular architecture can be controlled with precision.

We use Kelvin probe force microscopy (KPFM) to probe the carrier-dependent potential of an electrostatically defined quantum dot (QD) in a graphene/hexagonal boron nitride (hBN) heterostructure. We show that gate-dependent measurements enable a calibration scheme that corrects for uncertainty inherent in typical KPFM measurements and accurately reconstructs the potential well profile. Our measurements reveal how the well changes with carrier concentration, which we associate with the nonlinear dependence of graphene’s work function on carrier density. These changes shift the energy levels of quasi-bound states in the QD which we can measure via scanning tunneling spectroscopy (STS). We show that the experimentally extracted energy levels closely compare with wave functions calculated from the reconstructed KPFM data. This methodology, where KPFM and STS data are simultaneously acquired from 2D materials, allows the quasiparticle response to an electrostatic potential to be determined in a self-consistent way.

The MORDOR I trial1, conducted in Niger, Malawi and Tanzania, demonstrated that mass azithromycin distribution to preschool children reduced childhood mortality1. However, the large but simple trial design precluded determination of the mechanisms involved. Here we examined the gut microbiome of preschool children from 30 Nigerien communities randomized to either biannual azithromycin or placebo. Gut microbiome γ-diversity was not significantly altered (P= 0.08), but the relative abundances of two Campylobacterspecies, along with another 33 gut bacteria, were significantly reduced in children treated with azithromycin at the 24-month follow-up. Metagenomic analysis revealed functional differences in gut bacteria between treatment groups. Resistome analysis showed an increase in macrolide resistance gene expression in gut microbiota in communities treated with azithromycin (P= 0.004). These results suggest that prolonged mass azithromycin distribution to reduce childhood mortality reduces certain gut bacteria, including known pathogens, while selecting for antibiotic resistance.

Carbon dots (CDs) are a novel class of nanoparticles with excellent properties. The development of CDs involves versatile synthesis, characterization, and various applications. However, the importance of surface chemistry of CDs, especially in applications, is often underestimated. In fact, the study of the surface chemistry of CDs is of great significance in the explanation of the unique properties of CDs as well as the pursuit of potential applications. In this feature article, we do not only introduce the development of CDs in our group but also highlight their applications where surface chemistry plays a critical role.

Carbon dots (CDs) are zero-dimensional carbon-based spherical nanoparticles with diameters less than 10 nm. Here, we report for the first time CDs forming stable Langmuir monolayers at the air–subphase interface. Langmuir monolayers are of great interest both fundamentally to study the interactions at the interfaces and for many applications such as the development of sensors. However, CDs usually do not form Langmuir monolayers because of their highly hydrophilic nature. In this study, amphiphilic CDs were prepared through hydrothermal carbonization using saccharides as the precursors. The surface chemistry behavior and optical properties of CDs at the air–subphase interface were studied. CDs derived from saccharides consistently formed stable Langmuir monolayers which show all essential phases, namely, gas, liquid-expanded, liquid-condensed, and solid phases. The compression–decompression cycle method showed minimum hysteresis (4.3%), confirming the retaining capacity of the CDs as a monolayer. Limiting CD areas from surface pressure–area isotherm at the air–subphase interface were used to calculate the average diameter of the CDs at the air–subphase interface. UV/vis absorption spectra of CDs dispersed in water and in Langmuir monolayers had the same bands in the UV region. The intensity of the UV/vis absorption increases with increasing surface pressure at the air–subphase interface. Interestingly, photoluminescence (PL) of the Langmuir monolayer of CDs was excitation-independent, whereas the same CDs had excitation-dependent PL when dispersed in water.

Carbon dots have often been studied to investigate their unique optical properties such as excitation wavelength-independence emission. Carbon dots have also been shown to undergo electron transfer in different situations. This study endeavors to investigate the properties of carbon dots’ photoluminescence and electron transfer. Herein, the preparation and characterization of carbon dots which exhibit long wavelength photoluminescence has been reported. These carbon dots exhibit quenching when exposed to metal ions in proportion to the reduction potential of the metal, which experimental evidence has shown for the first time. This property of metal ion reduction potential-dependent quenching has been studied to show the collisional electron transfer from amine groups in carbon dots to the metal ions. Therefore, the photoluminescence in these carbon dots is directly related to organic functional groups on the surface of the carbon dots.

In contrast to the recent immense attention in carbon nitride quantum dots (CNQDs) as a heteroatom-doped carbon quantum dot (CQD), their biomedical applications have not been thoroughly investigated. Targeted cancer therapy is a prominently researched area in the biomedical field. Here, the ability of CNQDs as a selective bioimaging nanomaterial was investigated to assist targeted cancer therapy. CNQDs were first synthesized using four different precursor sets involving urea derivatives, and the characteristics were compared to select the best candidate material for bioapplications. Characterization techniques such as UV–vis, luminescence, X-ray photoelectron spectroscopy, nuclear magnetic resonance spectroscopy, and transmission electron microscopy were used. These CNQDs were analyzed in in vitrostudies of bioimaging and labeling using pediatric glioma cells (SJGBM2) for possible selective biolabeling and nanodistribution inside the cell membrane. The in vitrocellular studies were conducted under long-wavelength emission without the interference of blue autofluorescence. Thus, excitation-dependent emission of CNQDs was proved to be advantageous. Importantly, CNQDs selectively entered SJGBM2 tumor cells, while it did not disperse into normal human embryonic kidney cells (HEK293). The distribution studies in the cell cytoplasm indicated that CNQDs dispersed into lysosomes within approximately 6 h after the incubation. The CNQDs exhibited great potential as a possible nanomaterial in selective bioimaging and drug delivery for targeted cancer therapy.

The probability that a nucleus will absorb a neutron—the neutron capture cross-section—is important to many areas of nuclear science, including stellar nucleosynthesis, reactor performance, nuclear medicine and defence applications. Although neutron capture cross-sections have been measured for most stable nuclei, fewer results exist for radioactive isotopes, and statistical-model predictions typically have large uncertainties1. There are almost no nuclear data for neutron-induced reactions of the radioactive nucleus 88Zr, despite its importance as a diagnostic for nuclear security. Here, by exposing 88Zr to the intense neutron flux of a nuclear reactor, we determine that 88Zr has a thermal neutron capture cross-section of 861,000 ± 69,000 barns (1σuncertainty), which is five orders of magnitude larger than the theoretically predicted value of 10 barns2. This is the second-largest thermal neutron capture cross-section ever measured and no other cross-section of comparable size has been discovered in the past 70 years. The only other nuclei known to have values greater than 105barns3–6are 135Xe (2.6 × 106barns), a fission product that was first discovered as a poison in early reactors7,8, and 157Gd (2.5 × 105barns), which is used as a detector material9,10, a burnable reactor poison11and a potential medical neutron capture therapy agent12. In the case of 88Zr neutron capture, both the target and the product (89Zr) nuclei are radioactive and emit intense γ-rays upon decay, allowing sensitive detection of miniscule quantities of these radionuclides. This result suggests that as additional measurements with radioactive isotopes become feasible with the operation of new nuclear-science facilities, further surprises may be uncovered, with far-reaching implications for our understanding of neutron capture reactions.

Submicrometer-thick layers of hexagonal boron nitride (hBN) exhibit high in-plane thermal conductivity and useful optical properties, and serve as dielectric encapsulation layers with low electrostatic inhomogeneity for graphene devices. Despite the promising applications of hBN as a heat spreader, the thickness dependence of its cross-plane thermal conductivity is not known, and the cross-plane phonon mean free paths (MFPs) have not been measured. We measure the cross-plane thermal conductivity of hBN flakes exfoliated from bulk crystals. We find that submicrometer thick flakes exhibit thermal conductivities up to 8.1 ± 0.5 W m–1K–1at 295 K, which exceeds previously reported bulk values by more than 60%. Surprisingly, the average phonon mean free path is found to be several hundred nanometers at room temperature, a factor of 5 larger than previous predictions. When planar twist interfaces are introduced into the crystal by mechanically stacking multiple thin flakes, the cross-plane thermal conductivity of the stack is found to be a factor of 7 below that of individual flakes with similar total thickness, thus providing strong evidence that phonon scattering at twist boundaries limits the maximum phonon MFPs. These results have important implications for hBN integration in nanoelectronics and improve our understanding of thermal transport in two-dimensional materials.

We examined norovirus contamination on hands of ill patients during 12 norovirus outbreaks in 12 long-term care facilities (LTCFs). The higher frequency and norovirus titers on hands of residents compared to hands of heathcare workers highlights the importance of adhering to appropriate hand hygiene practices during norovirus outbreaks in LTCFs.Infect Control Hosp Epidemiol2018;39:219–221

The article presents tax cases concerning tax procedures. It examines the ruling of the Tax Court on an amended return filed by a taxpayer after the Internal Revenue Service (IRS) has issued summons related to the tax transaction that. In another case, the Fifth Circuit discusses the decision of a lower court on the penalties under Section 6662 of the U.S. Code for a fake partnership that was allegedly used as cover to reduce a partner's income tax liability.

The transparency of the eye lens is vital for maintenance of good image quality to the eye. This is lost when the lens develops a cataract which is a manifestation of changes to the structural proteins and their organisation. Understanding the complex arrangements and interactions of proteins in the lens and how these alter with opacification requires a means of probing the intact tissue. Nanoparticles offer such potential but need to be tested on lens cells and proteins to see whether they cause any detrimental changes. Cerium oxide nanoparticles (nanoceria) of around 5-6nm were prepared and characterised. A concentration of 10g/ml was introduced into cell cultures from porcine eye lens epithelial cells and from a commercially available human cell line. Transmission electron microscopy of treated samples showed nanoparticles within cells. Proteins extracted from the cultured cells were subjected to chromatography and electrophoresis. Chromatographs and electrophoresis gels showed no difference between treated and control samples from human lens cell cultures. Some slight differences, between treated and control samples, were noted in porcine samples. The results suggest that introduction of nanoceria into cultured cells from the eye lens do not manifest any significant effects on chromatographic or electrophoretic profiles of eye lens proteins.

As the surgical indications for total knee replacement (TKR) expand to include younger, heavier and more active patients, knowledge of the effect of these demographic variables on the outcome and survival of the implant is increasingly important.Between November 1986 and September 1990, 402 patients underwent 562 primary cemented cruciate-retaining TKRs carried out by a single surgical team. The overall results showed a survival of 96.8% at 14 years with 1.44% lost to follow-up. Evaluating the demographics of these patients showed that certain groups fared significantly less well. The best results were seen in non-obese women with osteoarthritis who were over 60 years of age in whom there was ten-year survival of 99.4%. The worst results were in obese men with osteoarthritis who were less than 60 years of age in whom there was a ten-year survival of 35.7%. Caution should be exercised when considering TKR on a patient with this combination of poor risk factors.By identifying demographic factors at the time of consultation the surgeon is better able to predict the survival of the TKR. This information is important when considering the best options for treatment of a patient and in providing accurate information during preoperative counselling.

To determine if blind people have heightened tactile spatial acuity.

Experiments were performed using the standardized murine model of Helicobacter pylori infection to determine the immunogenicity of H. pylori outer membrane vesicles in immune protection. These vesicles, which are naturally shed from the surface of the bacterium, induce a protective response when administered intragastrically to mice in the presence of cholera holotoxin, despite the absence of the urease enzyme and associated Hsp54 chaperonin. Immunoblotting identified a specific serum immunoglobulin G (IgG) response to an 18-kDa outer membrane protein in a significant number of immunized animals. This commonly expressed, immunodominant protein was subsequently identified as lipoprotein 20 (Lpp20). Hybridoma backpacks secreting an IgG1 subclass monoclonal antibody to Lpp20 were generated in H. pylori-infected mice and were found to significantly reduce bacterial numbers, providing evidence that this surface-exposed antigen is a true vaccine candidate and not merely an antigenic marker for successful, protective immunization.

Ovarian follicular development is dependent on growth and differentiation of the oocyte, as well as the granulosa and theca cell layers. The majority of primary follicles in the adult human ovary are not growing, and most antral follicles undergo atresia. The mechanisms regulating follicular growth and differentiation are poorly understood. Expression of key regulatory proteins in cells of certain follicles may be involved. We have studied the distribution of retinoblastoma protein (pRb), a key cell cycle regulator, in human follicles and CL by quantitative immunohistochemistry. Recent studies suggest that high nuclear concentrations of pRb are associated with the arrest of cell proliferation and the beginning of differentiation; during advanced differentiation of cells pRb is markedly depleted or absent. We also studied follicular distribution of Thy-1 differentiation protein, a morpho-regulatory molecule associated with cell differentiation, and the presence of macrophages. Macrophages have been shown to stimulate steroidogenesis in granulosa cells in vitro, and they are required for release of Thy-1 differentiation protein from vascular pericytes among granulosa cells in vivo. Our results indicate that oocytes in resting follicles exhibit pRb in the nucleoli. During initiation of follicular growth, the pRb expression first extends over the oocyte nuclei and then diminishes from both nuclei and nucleoli in preantral follicles. When the oocytes reach maximum size in small antral follicles, the pRb expression is reestablished in oocyte nucleoli. In differentiating granulosa and theca cell layers of preantral and small antral follicles, pRb expression is high, but it is low in growing large antral follicles. During CL development and regression, pRb expression in the nuclei of granulosa lutein cells first increases and then decreases. Follicular development is accompanied by the presence of Thy-1 differentiation protein and macrophages under the follicular basement membrane. In growing large antral follicles, during the mid-follicular phase, larger macrophages exhibit physical contacts with granulosa cells through the follicular basement membrane, and, during the late follicular phase, small dendritic macrophages can be detected among granulosa cells, but not within the follicular antrum. Large antral follicles undergoing atresia exhibit strong pRb expression in granulosa cells. This is accompanied by a lack of Thy-1 differentiation protein among granulosa cells and the occurrence of large phagocytic macrophages in the follicular antrum. This is the first report of pRb expression in the human ovary. Our data show that enhanced pRb expression accompanies initiation of oocyte growth and differentiation of granulosa and theca cells, and that low levels of pRb accompany advanced differentiation of these cells. Differentiation of preantral and antral follicles is accompanied by release of Thy-1 differentiation protein from vascular pericytes and association of macrophages with differentiating cells.

Abstract: Serum-derived albumin has for a long time been used in cell culture media, but the exact role of albumin and/or impurities bound to albumin has not been precisely defined. In this study, recombinant human albumin was evaluated for its growth-promoting activity on two cell lines, NRK and SCC-9. For NRK cells, the recombinant human albumin was found to exert an inhibitory effect. The fact that fatty acid free HSA was also inhibitory while HSA fraction V was stimulatory suggested a role for fatty acids or some other bound moieties in growth stimulation by HSA fraction V. Addition of oleic acid, cholesterol, phosphatidylcholine, phosphatidylserine or a combination of these lipids, however, did not significantly improve the growth stimulating activity of either fatty acid free HSA or the recombinant human albumin. For SCC-9 cells, both recombinant human albumin and fatty acid free HSA showed slight stimulation (although they were not as active as HSA fraction V), suggesting that in some cell systems, the albumin molecule per se may promote cell growth and survival.

Abstract

It is now accepted that some patients will fail to respond clinically to one non-steroidal anti-inflammatory drug but will respond to another apparently similar compound (8). There are a number of possible reasons for this failure to respond such as the use of inadequate dosage or inappropriate drugs. However these reasons are unlikely to be applicable in the situation outlined above and we have been interested in exploring further, possible reasons for this failure to respond. We have therefore conducted two studies in patients with rheumatoid arthritis to examine the relationship between the pharmacokinetics of the drugs used, the clinical response to the drug, and certain biochemical effects of the drugs. The initial study with indometha-cin was reported more fully in 1979 (3) and the second study was reported more briefly in 1980 (II). This report reviews the initial study and reports on some new data in the second study.

The objectives of this study were to determine the point prevalence of neurophysiologically defined median nerve compression and associated carpal tunnel syndrome in a random sample of the general population. The design was a two-stage screening study; (i) a cross-sectional survey to estimate the point prevalence of current hand symptoms; (ii) nerve conduction testing of the median nerve in weighted samples of the survey respondents. The target study population was a random sample of 1000 adults aged between 18 and 75 yr registered with a family practice in the UK. A mailed questionnaire enquired about hand symptoms on the day and included various demographic questions. Weighted random samples were taken based on the hand symptoms reported, and the subjects were invited to attend for motor and sensory median nerve conduction testing. A neurophysiological diagnosis of median nerve compression was made based on a number of different cut-offs using published criteria. Of those receiving a questionnaire, 79% responded. A total of 250 responders were invited to attend for nerve conduction testing, of whom 155 (62%) attended. Non-response to the questionnaire and non-attendance for nerve conduction testing may have biased the prevalence estimates. After adjustment for such biases, a prevalence estimate of between 7 and 16% was obtained, varying with the different cut-offs used to define delayed median nerve conduction. Subjects over 54 yr of age had a higher prevalence than younger participants. There was no difference in prevalence estimates between men and women. The conclusion reached was that carpal tunnel syndrome, as assessed by delayed median nerve conduction, is common in the general population.Keywords:Carpal tunnel syndrome, Prevalence, Epidemiology.

The objectives of this study were to determine the point prevalence of neurophysiologically defined median nerve compression and associated carpal tunnel syndrome in a random sample of the general population. The design was a two-stage screening study; (i) a cross-sectional survey to estimate the point prevalence of current hand symptoms; (ii) nerve conduction testing of the median nerve in weighted samples of the survey respondents. The target study population was a random sample of 1000 adults aged between 18 and 75 yr registered with a family practice in the UK. A mailed questionnaire enquired about hand symptoms on the day and included various demographic questions. Weighted random samples were taken based on the hand symptoms reported, and the subjects were invited to attend for motor and sensory median nerve conduction testing. A neurophysiological diagnosis of median nerve compression was made based on a number of different cut-offs using published criteria. Of those receiving a questionnaire, 79% responded. A total of 250 responders were invited to attend for nerve conduction testing, of whom 155 (62%) attended. Non-response to the questionnaire and non-attendance for nerve conduction testing may have biased the prevalence estimates. After adjustment for such biases, a prevalence estimate of between 7 and 16% was obtained, varying with the different cut-offs used to define delayed median nerve conduction. Subjects over 54 yr of age had a higher prevalence than younger participants. There was no difference in prevalence estimates between men and women. The conclusion reached was that carpal tunnel syndrome, as assessed by delayed median nerve conduction, is common in the general population.
Keywords:Carpal tunnel syndrome, Prevalence, Epidemiology.

The computer program NRLXRF has been applied to the determination of minor and trace constituents in aluminum alloys and several National Bureau of Standards certified standard reference materials. Limitations arising from energy dispersive x-ray analysis and the fundamental-parameter method used by NRLXRF are illustrated.

• To study the long-range results of surgically treated intermittent exotropia, 100 consecutive patients have been followed up for an average of 6.1 years. In all cases, the initial procedure was bilateral recession of the lateral rectus muscles. The overall functional cure rate was 78%. To accomplish this result, 27 patients were operated on a second time, 21 for undercorrection and six for overcorrection.A number of patients cooperated very poorly or were lost to follow-up while still under treatment. Had these patients been eliminated from the series, the cure rate would have been greater than 90%.In this study, bilateral recession of the lateral rectus muscles corrected the distant measurement more than the near measurement only with the divergence excess type of deviation. Also, this procedure was not notably more effective with divergence excess than with basic-type intermittent exotropia.

Previous studies evaluating porcine zona pellucida antigens for immunocontraceptive purposes have in some cases revealed altered ovarian function in association with antibody response. This study was undertaken in an attempt to identify zona immunogens that do not cause adverse endocrine effects. To this end, we investigated the effects of highly purified preparations of native and deglycosylated pig zona pellucida antigens on ovarian function and immune response in the rabbit. Thirty female rabbits were immunized, 5 per group, with 100 micrograms each of either 1) SIZP, solubilized isolated zonae pellucidae; 2) ZP3, a purified porcine zona preparation containing the two principle glycoproteins, ZP3 α and ZP3 β, endo-β-galactosidase-digested ZP3 glycoproteins (~ 30% deglycosylated) termed 3) ZP3 α/EBGD and 4) ZP3 β/EBGD; and chemically deglycosylated ZP3 α and ZP3 β (≥ to 92% deglycosylated), termed 5) ZP3 α/DG and 6) ZP3 β/DG. Rabbits injected with saline (n = 2) or Freund's adjuvant alone (n = 3) served as controls. Serum LH, FSH, estradiol, and progesterone were measured at 5-day intervals during seven 20-day cycles of hCG-induced pseudopregnancy over 42 wk. Anti-ZP3 titers, determined by RIA, developed in all treatment groups and correlated directly with carbohydrate content. Animals immunized with SIZP, ZP3, and ZP3 β/EBGD showed a significant elevation of LH and FSH and a significant decline of peak progesterone levels by the fourth pseudopregnancy cycle. In contrast, animals immunized with ZP3 α/EBGD, ZP3 α/DG, and ZP3 β/DG showed no significant elevations of gonadotropins and continued to display cyclic progesterone secretion in response to hCG. These data implicate zona carbohydrate in the pathogenesis of ovarian dysfunction associated with zona antigen immunization, and encourages the use of specific deglycosylated zona molecules in the continued efforts to develop a zona-based contraceptive vaccine.