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Background In view of reported associations between high adiposity, particularly in midlife and late-life dementia risk, we aimed to determine associations between body mass index (BMI), and BMI changes across adulthood and brain structure and pathology at age 69–71 years. Methods Four hundred sixty-five dementia-free participants from Insight 46, a sub-study of the British 1946 birth cohort, who had cross-sectional T1/FLAIR volumetric MRI, and florbetapir amyloid-PET imaging at age 69–71 years, were included in analyses. We quantified white matter hyperintensity volume (WMHV) using T1 and FLAIR 3D-MRI; β-amyloid (Aβ) positivity/negativity using a SUVR approach; and whole brain (WBV) and hippocampal volumes (HV) using 3D T1-MRI. We investigated the influence of BMI, and BMI changes at and between 36, 43, 53, 60–64, 69 and 71 years, on late-life WMHV, Aβ-status, WBV and mean HV. Analyses were repeated using overweight and obese status. Results At no time-point was BMI, change in BMI or overweight/obese status associated with WMHV or WBV at age 69–71 years. Decreasing BMI in the 1–2 years before imaging was associated with an increased odds of being β-amyloid positive (OR 1.45, 95% confidence interval 1.09, 1.92). There were associations between being overweight and larger mean HV at ages 60–64 (β = 0.073 ml, 95% CI 0.009, 0.137), 69 (β = 0.076 ml, 95% CI 0.012, 0.140) and 71 years (β = 0.101 ml, 95% CI 0.037, 0.165). A similar, albeit weaker, trend was seen with obese status. Conclusions Using WMHV, β-amyloid status and brain volumes as indicators of brain health, we do not find evidence to explain reported associations between midlife obesity and late-life dementia risk. Declining BMI in later life may reflect preclinical Alzheimer’s disease.

The Wide-Field Infrared Transient Explorer (WINTER) is a new infrared time-domain survey instrument which will be deployed on a dedicated 1 meter robotic telescope at Palomar Observatory. WINTER will perform a seeing-limited time domain survey of the infrared (IR) sky, with a particular emphasis on identifying r-process material in binary neutron star (BNS) merger remnants detected by LIGO. We describe the scientific goals and survey design of the WINTER instrument. With a dedicated trigger and the ability to map the full LIGO O4 positional error contour in the IR to a distance of 190 Mpc within four hours, WINTER will be a powerful kilonova discovery engine and tool for multi-messenger astrophysics investigations. In addition to follow-up observations of merging binaries, WINTER will facilitate a wide range of time-domain astronomical observations, all the while building up a deep coadded image of the static infrared sky suitable for survey science. WINTER's custom camera features six commercial large-format Indium Gallium Arsenide (InGaAs) sensors and a tiled optical system which covers a $>$1-square-degree field of view with 90% fill factor. The instrument observes in Y, J and a short-H (Hs) band tuned to the long-wave cutoff of the InGaAs sensors, covering a wavelength range from 0.9 - 1.7 microns. We present the design of the WINTER instrument and current progress towards final integration at Palomar Observatory and commissioning planned for mid-2021., Published in SPIE Astronomical Telescopes + Instrumentation 2020, Ground-based and Airborne Instrumentation for Astronomy VIII 14 pages, 7 figures

The Wide-field Infrared Transient Explorer (WINTER) is a 1x1 degree infrared survey telescope under development at MIT and Caltech, and slated for commissioning at Palomar Observatory in 2021. WINTER is a seeing-limited infrared time-domain survey and has two main science goals: (1) the discovery of IR kilonovae and r-process materials from binary neutron star mergers and (2) the study of general IR transients, including supernovae, tidal disruption events, and transiting exoplanets around low mass stars. We plan to meet these science goals with technologies that are relatively new to astrophysical research: hybridized InGaAs sensors as an alternative to traditional, but expensive, HgCdTe arrays and an IR-optimized 1-meter COTS telescope. To mitigate risk, optimize development efforts, and ensure that WINTER meets its science objectives, we use model-based systems engineering (MBSE) techniques commonly featured in aerospace engineering projects. Even as ground-based instrumentation projects grow in complexity, they do not often have the budget for a full-time systems engineer. We present one example of systems engineering for the ground-based WINTER project, featuring software tools that allow students or staff to learn the fundamentals of MBSE and capture the results in a formalized software interface. We focus on the top-level science requirements with a detailed example of how the goal of detecting kilonovae flows down to WINTER's optical design. In particular, we discuss new methods for tolerance simulations, eliminating stray light, and maximizing image quality of a fly's-eye design that slices the telescope's focus onto 6 non-buttable, IR detectors. We also include a discussion of safety constraints for a robotic telescope., Comment: Published in SPIE Astronomical Telescopes + Instrumentation 2020, Ground-based and Airborne Instrumentation for Astronomy VIII. 12 pages, 9 figures

OBJECTIVE: The authors studied the results of laparoscopic colectomies performed by a surgical team on 80 consecutive patients and compared these results with standard open colectomies. METHODS: Eight consecutive laparoscopic-assisted colectomies were performed by Norfolk Surgical Group in a 14-month period and compared to 53 patients who had a conventional open colectomies. Analysis included indications for surgery, types of procedure, complications, incidence and causes for conversion, length of procedure, duration of postoperative ileus, hospital stay, operating room and total hospital charges, and examination of the pathologic specimens. RESULTS: Many different types of colectomies were performed successfully and safely for a variety of surgical indications. The conversion rate was 22.5%, which decreased to 15% in the second half of the series. Complications in patients who underwent laparoscopic operations were not severe in number of type. The length of the operative procedure, operating room charge, and the total hospital charge were greater for patients undergoing laparoscopic-assisted colectomies. Patients who underwent laparoscopic operations had a shorter period of postoperative ileus and less pain, resumed a regular diet sooner, and were discharged from the hospital sooner than patients who underwent open colectomies. There was no significant difference in the pathology specimens obtained by laparoscopic-assisted colectomies compared with conventional open colectomies for length of specimen, surgical margins, and number of lymph nodes retrieved. CONCLUSIONS: This study indicated that laparoscopic techniques can be applied safely and effectively to a broad range of colonic operations. Laparoscopic-assisted colectomies take longer to perform and are more costly, but are associated with less paralytic ileus, less pain, and reduced hospital stay. Laparoscopic colectomies for the treatment of malignancy are achievable technically, but will require careful long-term study.

Social responsibility is a concept often used to describe how large corporations, or even small businesses, should “give back” something to the communities that they serve. We feel the same is true when it comes to faculty members. Oftentimes, the greatest expertise in a given subject area in a community is housed within the confines of the faculty members of the local college or university and such knowledge and expertise can be shared in a plethora of venues as part of the “service” component of their annual evaluation. Our paper sets forth an example of such faculty involvement in an attempt to improve the decision-making of our incoming students and, as a result, the overall community by providing a presentation to our Freshman Seminar courses on the legal ramifications of poor decision-making as they begin to manage their newfound freedom of choices. In our paper, we point out the pedagological system that we use to emphasize the importance of making the right choices for now, which will clearly have a direct effect upon their future.

Inclusion of vagotomy and pyloroplasty in the surgical treatment of gastroesophageal reflux associated with hiatal hernia has long been controversial. To evaluate the morbidity of vagotomy in the treatment of reflux esophagitis, a retrospective study of 311 patients treated by the Hill posterior gastropexy technique of hiatal hernia repair was tabulated. Vagotomy with the anti-reflux operation was performed upon 159 patients (51%). Vagotomy was not included for 152 patients (49%). The incidence of postoperative symptoms with or without vagotomy was almost equally divided--41% without vagotomy and 47% with vagotomy. However, the major postoperative symptoms that occurred in both groups were abdominal cramps and bloating which usually disappeared in the early postoperative period and were attributed to the anti-reflux procedure and not to vagotomy. When vagotomy was included with the anti-reflux operation, the incidence and duration of long term, disabling postoperative symptoms were significantly increased. Diarrhea occurred two times more frequently. Nausea and vomiting occurred ten times more frequently and dumping was present only in vagotomized patients. Long term postoperative symptoms, judged on a basis of symptoms lasting longer than three months duration, occurred in 1% of patients without vagotomy and 26% when vagotomy was included. This study revealed that no additional protection against recurrent symptoms of gastroesophageal reflux or radiographic evidence of recurrent hiatal hernia was provided by inclusion of vagotomy. In conclusion, vagotomy is contraindicated in the treatment of gastroesophageal reflux except in the presence of peptic ulcer disease.

Conditions are given which imply the convergence to zero of solutions of the second order damped nonlinear ordinary differential equation \[ \left( r(t)u'\right) ' + \phi \left( t,u,u'\right) u' + p(t)f(u) = h\left( t,u,u'\right) \]. In the case when $h = 0$, the uniform stability and uniqueness of the zero solution on the ray $[ 0,\infty )$ are also established. The proofs are based on the construction of Lyapunov functions.

Conditions are given on the functions p, q, $\phi $, and g which imply that all continuable solutions of \[ u'' + q( t )\phi ( {u,u'} ) + p( t )u^\alpha g( {u'} ) = 0 \] are oscillatory on the ray $[ {0,\infty } )$ when $\alpha > 0$ is the quotient of odd integers and $\alpha \ne 1$. When $q = 0$ and $g = 1$, these theorems reduce to the well-known sufficiency theorems of Atkinson and Belohorec.

1. The semigroup analogue of the Pontrjagin duality theorem was first studied in [1]. In that paper, it was shown that a necessary and sufficient condition for duality in discrete abelian semigroups is that the semigroup be a union of groups and have an identity element. Such semigroups we shall call inverse semigroups. For compact abelian topological semigroups it was shown in [1] that the separation of points by semicharacters is a sufficient condition for duality in an inverse semigroup with identity. In [2] it was shown that, in any topological abelian semigroup, a necessary condition for duality is that the semigroup be an inverse semigroup with identity and continuous inversion. In this paper we obtain necessary and sufficient conditions that semicharacters separate points in a topological abelian inverse semigroup with identity which is compact, or locally compact with continuous inversion. In the compact case we obtain the same result as has been given by Sneperman [5], using different methods. 1.1. DEFINITION. An abelian semigroup is a nonempty set S together with a map m: (x, y)-*xy on SXS to S, such that x(yz) = (xy)z and xy =yx for all x, y and z in S. If S is a Hausdorff topological space and the mapping m is continuous, S is called a topological abelian semigroup. 1.2. DEFINITION. A semicharacter X of a topological abelian semigroup S is a bounded, continuous, complex-valued function on S, not identically zero, satisfying x(xy) =x(x)x(y) for all x and y in S. We denote the set of semicharacters of S by SA. We endow SA with the compact open topology. The following facts aretobefoundin [1], [3]or [4]. 1.3. If S has an identity element, S^ becomes a topological abelian semigroup, when endowed with the operation of pointwise multiplication. 1.4. If S has an identity element, and is discrete, S^ is a compact abelian semigroup [1, 3.1 ]. 1.5. We call S an abelian inverse semigroup if S is an abelian semigroup which is a union of groups. If S is a topological, abelian inverse semigroup with an identity element then S"" is of the same type. Further, if S is compact then S^ is discrete [1, 6.11.

Sufficient conditions are given so that all solutions of the nonlinear differential equation u ″ + φ ( t , u , u ′) u ′ + p ( t ) gf ( u ) g ( u ′) = h ( t , u , u ′) are continuable to the right of an initial t -value t 0 ⩾ 0. These conditions are then extended so that all solutions u of the equation in question together with their derivative u ′ are bounded for t ⩾ t 0 .

Encouraged by their experience since 1978 with blunt esophagectomy and gastric reconstruction in the management of pharyngolaryngeal malignancy, the authors have extended their use of this technique to the management of thoracic esophageal cancer. A study of 43 blunt esophageal resections is presented; 23 were performed in the management of pharyngolaryngeal cancer, and 20 were performed (22 attempted) for the resection of intrathoracic esophageal cancer. In the first group, two deaths occurred secondary to liver failure in cirrhotic patients with moist ascites. One death occurred due to anastomotic leak in the neck of a patient with laryngeal cancer treated with extended mediastinal dissection and tracheal resection for surgical and radiation failure. Two tracheal injuries occurred; one could be managed through the neck, and one required thoractomy for repair. In the 20 resections performed for intrathoracic cancer, there were no deaths, no tracheal injuries, and one chest was explored for bleeding in the splenic bed, which decompressed itself into the right chest. The overall mortality was 7.5%. The evaluation emphasizes: The applicability of this technique for the management of esophageal problems at all levels. The safety of the technique, particularly in the typical population with advanced aged and severe underlying medical illness. Good functional results with palliation and/or cure. The benefit of intact mediastinal pleura in avoiding certain thoracic complications. The authors conclude that blunt esophagectomy is a safe resection procedure with limited morbidity and mortality, and that gastric reconstruction is reliable and affords excellent functional results. They are encouraged to continue management of panesophageal cancer with this technique.