Evidence of a Hardening in the Cosmic Ray Proton Spectrum at around 166 TeV Observed by the GRAPES-3 Experiment.

We present the measurement of the cosmic ray proton spectrum from 50 TeV to 1.3 PeV using 7.81×10^{6} extensive air shower events recorded by the ground-based GRAPES-3 experiment between 1 January 2014 and 26 October 2015 with a live time of 460 day. Our measurements provide an overlap with direct observations by satellite and balloon-based experiments. The electromagnetic and muon components in the shower were measured by a dense array of plastic scintillator detectors and a tracking muon telescope, respectively. The relative composition of the proton primary from the air shower data containing all primary particles was extracted using the multiplicity distribution of muons which is a sensitive observable for mass composition. The observed proton spectrum suggests a spectral hardening at ∼166 TeV and disfavors a single power law description of the spectrum up to the Knee energy (∼3 PeV).

Exceptional phonon point versus free phonon coupling in Zn1-xBexTe under pressure: an experimental and ab initio Raman study.

Raman scattering and ab initio Raman/phonon calculations, supported by X-ray diffraction, are combined to study the vibrational properties of Zn1-xBexTe under pressure. The dependence of the Be-Te (distinct) and Zn-Te (compact) Raman doublets that distinguish between Be- and Zn-like environments is examined within the percolation model with special attention to x ~ (0,1). The Be-like environment hardens faster than the Zn-like one under pressure, resulting in the two sub-modes per doublet getting closer and mechanically coupled. When a bond is so dominant that it forms a matrix-like continuum, its two submodes freely couple on crossing at the resonance, with an effective transfer of oscillator strength. Post resonance the two submodes stabilize into an inverted doublet shifted in block under pressure. When a bond achieves lower content and merely self-connects via (finite/infinite) treelike chains, the coupling is undermined by overdamping of the in-chain stretching until a «phonon exceptional point¼ is reached at the resonance. Only the out-of-chain vibrations «survive¼ the resonance, the in-chain ones are «killed¼. This picture is not bond-related, and hence presumably generic to mixed crystals of the closing-type under pressure (dominant over the opening-type), indicating a key role of the mesostructure in the pressure dependence of phonons in mixed crystals.

Phonon-based partition of (ZnSe-like) semiconductor mixed crystals on approach to their pressure-induced structural transition.

The generic 1-bond → 2-mode "percolation-type" Raman signal inherent to the short bond of common A1-xBxC semiconductor mixed crystals with zincblende (cubic) structure is exploited as a sensitive "mesoscope" to explore how various ZnSe-based systems engage their pressure-induced structural transition (to rock-salt) at the sub-macroscopic scale-with a focus on Zn1-xCdxSe. The Raman doublet, that distinguishes between the AC- and BC-like environments of the short bond, is reactive to pressure: either it closes (Zn1-xBexSe, ZnSe1-xSx) or it opens (Zn1-xCdxSe), depending on the hardening rates of the two environments under pressure. A partition of II-VI and III-V mixed crystals is accordingly outlined. Of special interest is the "closure" case, in which the system resonantly stabilizes ante transition at its "exceptional point" corresponding to a virtual decoupling, by overdamping, of the two oscillators forming the Raman doublet. At this limit, the chain-connected bonds of the short species (taken as the minor one) freeze along the chain into a rigid backbone. This reveals a capacity behind alloying to reduce the thermal conductivity as well as the thermalization rate of photo-generated electrons.

High-resolution computed tomography evaluation of congenital aural atresia - how useful is this?

OBJECTIVE: To depict various temporal bone abnormalities on high-resolution computed tomography in congenital aural atresia patients, and correlate these findings with auditory function test results and microtia subgroup. METHODS: Forty patients (56 ears) with congenital malformation of the auricle and/or external auditory canal were evaluated. Auricles were graded according to Marx's classification, divided into subgroups of minor (grades I and II) and major (III and IV) microtia. Other associated anomalies of the external auditory canal, tympanic cavity, ossicular status, oval and round windows, facial nerve, and inner ear were evaluated. RESULTS: Minor and major microtia were observed in 53.6 and 46.4 per cent of ears respectively. Mean hearing levels were 62.47 and 62.37 dB respectively (p = 0.98). The malleus was the most commonly dysplastic ossicle (73.3 vs 80.8 per cent of ears respectively, p = 0.53). Facial nerve (mastoid segment) abnormalities were associated (p = 0.04) with microtia subgroup (80 vs 100 per cent in minor vs major subgroups). CONCLUSION: Microtia grade was not significantly associated with mean hearing levels or other ear malformations, except for external auditory canal and facial nerve (mastoid segment) anomalies. High-resolution computed tomography is essential in congenital aural atresia, before management strategy is decided.

Early Recognition of Fibrodysplasia Ossificans Progressiva-Important For the Clinician.

Fibrodysplasia ossificans progressiva is a rare disorder of heterotopic ossification. Procedures like biopsy and surgery are known to be aggravating factors in promoting heterotopic ossification Clues to clinical diagnosis may therefore be a great advantage to treating orthopedician. Valgus deformity of great toe is an important diagnostic clue for treating physicians and thus aids in preventing the clinicians from subjecting the patients to unnecessary invasive and traumatic procedures. Hence clinical clues to early diagnosis are important in establishing the correct diagnosis and directing future management.

Laparoscopic TEP repair of inguinal hernia does not alter testicular perfusion.

PURPOSE: The effect of laparoscopic TEP repair on testicular perfusion is unclear. The procedure entails dissection of testicular blood vessels off the hernial sac and incorporation of a prosthetic mesh. This carries at minimum, a theoretical risk of compromise in testicular blood supply, which in turn may affect fertility. Our study aims to establish if any alteration in testicular perfusion occurs in very early (24 h), early (1 week) or late postoperative period (3 months) after laparoscopic TEP repair in the Indian population. METHODS: In our prospective trial, 20 patients underwent unilateral and 8 underwent bilateral laparoscopic TEP hernia repairs using standard technique by experienced surgeons. Flow parameters of testicular, capsular and intratesticular artery were noted using color Doppler ultrasound preoperatively and postoperatively and the postoperative resistive indexes of operated side (n = 36) were compared with preoperative values. Additionally, for unilateral repairs, flow parameters on operated side were compared with the non-operated side. RESULTS: No statistically significant difference was noticed in the resistive index of the arteries upon comparing these postoperative with preoperative values. For unilateral repairs, the flow parameters of the operated side were comparable with that of non-operated side (i.e. p > 0.05). CONCLUSION: Laparoscopic TEP performed by experienced surgeons does not alter testicular flow dynamics in early or late postoperative period.

Deletion of G-protein-coupled receptor 55 promotes obesity by reducing physical activity.

BACKGROUND/OBJECTIVES: Cannabinoid receptor 1 (CB1) is the best-characterized cannabinoid receptor, and CB1 antagonists are used in clinical trials to treat obesity. Because of the wide range of CB1 functions, the side effects of CB1 antagonists pose serious concerns. G-protein-coupled receptor 55 (GPR55) is an atypical cannabinoid receptor, and its pharmacology and functions are distinct from CB1. GPR55 regulates neuropathic pain, gut, bone, immune functions and motor coordination. GPR55 is expressed in various brain regions and peripheral tissues. However, the roles of GPR55 in energy and glucose homeostasis are unknown. Here we have investigated the roles of GPR55 in energy balance and insulin sensitivity using GPR55-null mice (GPR55(-/-)). METHODS: Body composition of the mice was measured by EchoMRI. Food intake, feeding behavior, energy expenditure and physical activity of GPR55(-/-) mice were determined by indirect calorimetry. Muscle function was assessed by forced treadmill running test. Insulin sensitivity was evaluated by glucose and insulin tolerance tests. Adipose inflammation was assessed by flow cytometry analysis of adipose tissue macrophages. The expression of inflammatory markers in adipose tissues and orexigenic/anorexigenic peptides in the hypothalamus was also analyzed by real-time PCR. RESULTS: GPR55(-/-) mice had normal total energy intake and feeding pattern (i.e., no changes in meal size, meal number or feeding frequency). Intriguingly, whereas adult GPR55(-/-) mice only showed a modest increase in overall body weight, they exhibited significantly increased fat mass and insulin resistance. The spontaneous locomotor activity of GPR55(-/-) mice was dramatically decreased, whereas resting metabolic rate and non-shivering thermogenesis were unchanged. Moreover, GPR55(-/-) mice exhibited significantly decreased voluntary physical activity, showing reduced running distance on the running wheels, whereas muscle function appeared to be normal. CONCLUSIONS: GPR55 has an important role in energy homeostasis. GPR55 ablation increases adiposity and insulin resistance by selectively decreasing physical activity, but not by altering feeding behavior as CB1.

An analysis of surgical complications; a tool to improve surgical outcome.

Complications in surgery are an important cause of morbidity and mortality. Complications may result in an increased length of stay in hospital, repeat surgery, additional medical treatment, legal issues and increased costs. Classification and regular audit of complications is a useful tool to improve patient safety and surgical outcome. The purpose of this study is to identify and classify surgical complications and evaluate the various contributing factors. The complications were categorized by Clavein Dindo system as Grade 1:52 (29.1%), Grade II :45 (25.1%),Grade IIIa:26 (14.5%), Grade IIIB:25 (14%), Grade IVa:5 (2.8%), Grade IVb:0 and Grade V:26 (14.5%) . The complication rate was 5.3% and mortality rate was 0.8% in total 3336 surgical procedures. There was significantly higher mortality in complications due to patient related factors 23.4% (11/47), compared to technical factors 4.2% (2/48) and other factors 15.4% (13/84) (p value = 0.024). The mortality was significantly higher in the patients who required ICU care, 54% (20/37), in class B surgical procedures 22.4% (22/98) and those who developed complications after emergency procedures were 31% (14/45). The mortality was significantly higher in the patients who required medical intervention for various medical complications 30.1% (19/63) compared to those who required surgical intervention 8.4% (5/59) or were managed conservatively 3.5% (2/57) (p value = 0.0001).

Stapled haemorrhoidectomy in the operative treatment of grade III and IV haemorrhoids.

Stapled haemorrhoidectomy (SH) is a minimally invasive intervention that uses a stapling device which avoids the need for wounds in the sensitive anal area and reduces the pain after surgery. This study was undertaken in Nepal Medical College Teaching Hospital from January 2010 to December 2012 to evaluate the efficacy of this modality of treatment among patients (32) who presented in the Surgery OPD with grade III and grade IV haemorrhoids. The results of SH were evaluated by the relief of symptoms, severity of post operative pain, and complications of SH. Twenty five (78.1%) patients had grade III and 7 (21.9%) presented with grade IV hemorrhoids. The most frequent presentation reported in our study was bleeding per rectum with perianal prolapse. Mean operating time was 40-60 minutes whereas mean hospital stay was 1.9 days. Urinary retention was the most common complication found in 12 (37.5%) patients in the immediate post operative period. SH is a safe, rapid, and convenient surgical remedy for grade III and grade IV hemorrhoids with low rate of complications, minimal postoperative pain, and shorter hospital stay.

Ghrelin receptor regulates HFCS-induced adipose inflammation and insulin resistance.

BACKGROUND AND OBJECTIVES: High fructose corn syrup (HFCS) is the most commonly used sweetener in the United States. Some studies show that HFCS consumption correlates with obesity and insulin resistance, while other studies are in disagreement. Owing to conflicting and insufficient scientific evidence, the safety of HFCS consumption remains controversial. SUBJECTS/METHODS: We investigated the metabolic consequences of mice fed a (a) regular diet, (b) 'Western' high-fat diet or (c) regular diet supplemented with 8% HFCS in drinking water (to mimic soft drinks) for 10 months. Adipose tissue macrophages (ATMs) have emerged as a major pathogenic factor for obesity and insulin resistance. ATMs consist of proinflammatory F4/80(+)CD11c(+) macrophages and anti-inflammatory F4/80(+)CD11c(-) macrophages. In this study, we assessed the effects of HFCS on ATMs in intra-abdominal fat. RESULTS: We found that HFCS feeding in mice induced more severe adipose inflammation and insulin resistance than even the higher-calorie-containing 'Western' high-fat diet, and these HFCS-induced deleterious effects were independent of calorie intake or body fat content. We showed that similar to 'Western' high-fat diet, HFCS triggered a robust increase of both proinflammatory ATMs and anti-inflammatory ATMs in intra-abdominal fat. Remarkably, however, the anti-inflammatory ATMs were much less abundant in HFCS-fed mice than in high-fat-fed mice. Furthermore, we showed that deletion of the ghrelin receptor (growth hormone secretagogue receptor, GHS-R) ameliorates HFCS-induced adipose inflammation and insulin resistance. HFCS-fed GHS-R-null mice exhibit decreased proinflammatory ATMs in intra-abdominal fat, reduced adipose inflammation and attenuated liver steatosis. CONCLUSION: Our studies demonstrate that HFCS has detrimental effects on metabolism, suggesting that dietary guidelines on HFCS consumption for Americans may need to be revisited. GHS-R deletion mitigates the effects of HFCS on adipose inflammation and insulin resistance, suggesting that GHS-R antagonists may represent a novel therapy for insulin resistance.

Chemical reaction versus vibrational quenching in low energy collisions of vibrationally excited OH with O.

Quantum scattering calculations are reported for state-to-state vibrational relaxation and reactive scattering in O + OH(v = 2 - 3, j = 0) collisions on the electronically adiabatic ground state (2)A'' potential energy surface of the HO2 molecule. The time-independent Schrödinger equation in hyperspherical coordinates is solved to determine energy dependent probabilities and cross sections over collision energies ranging from ultracold to 0.35 eV and for total angular momentum quantum number J = 0. A J-shifting approximation is then used to compute initial state selected reactive rate coefficients in the temperature range T = 1 - 400 K. Results are found to be in reasonable agreement with available quasiclassical trajectory calculations. Results indicate that rate coefficients for O2 formation increase with increasing the OH vibrational level except at low and ultralow temperatures where OH(v = 0) exhibits a slightly different trend. It is found that vibrational relaxation of OH in v = 2 and v = 3 vibrational levels is dominated by a multi-quantum process.

Ultracold collisions of O(1D) and H2: the effects of H2 vibrational excitation on the production of vibrationally and rotationally excited OH.

A quantum dynamics study of the O((1)D) + H2(v = 0 - 2, j = 0) system has been carried out using the potential energy surfaces of Dobbyn and Knowles [Mol. Phys. 91, 1107 (1997)]. A time-independent quantum mechanical method based on hyperspherical coordinates is adopted for the dynamics calculations. Energy dependent cross section, probability, and rate coefficients are computed for the elastic, inelastic, and reactive channels over collision energies ranging from the ultracold to thermal regimes and for total angular momentum quantum number J = 0. The effect of initial vibrational excitation of the H2 molecule on vibrational and rotational populations of the OH product is investigated as a function of the collision energy. Comparison of results for vibrational levels v = 0 - 2 of H2 demonstrates that the vibrational excitation of H2 and its non-reactive relaxation pathway play a minor role in the overall collisional outcome of O((1)D) and H2. It is also found that while the state-resolved product vibrational distributions are sensitive to the initial collision energy and H2 vibrational level, the product rotational distribution depicts an inverted population that is largely insensitive to initial conditions. Rate coefficients evaluated using a J-shifting approximation show reasonable agreement with available theoretical and experimental results suggesting that the J-shifting approximation may be used to evaluate the rate coefficients for O((1)D) + H2 reaction.

Choledochoduodenostomy in the management of dilated common bile duct due to choledocholithiasis.

Choledochoduodenostomy (CDD) is the operative procedure for Choledocholithiasis in the presence of a dilated common bile duct (CBD). It has been reported as a most effective treatment of CBD stones than T-tube drainage but is regarded as a obsolete therapeutic method due to fears of higher morbidity, cholangitis, "sump" syndrome etc. This study was done prospectively to assess the aforementioned issues analyzing our two years (July 2009 - June 2011) experience.CDD was performed in 31 patients (22 females and 9 males) with aged 18 - 72 years. CBD stones were the only indications in all patients with 18 (45.1%) patients had cholangitis, 8 (35.4%) had cholecystitis and 5 (19.3%) had biliary colic. Abdominal sonogram revealed dilated CBD with single or multiple calculi. The diameter of CBD varies from 14 - 29mm with stone size being ranged from 10- 26mm.Early post operative complications were seen in 4 (12.9%) patients. Only one patient had recurrent cholangitis presented lately due to intrahepatic stones.CDD is a highly effective treatment for choledocholithiasis in all age group with low morbidity and mortality provided a wide anastomosis is accomplished.

Prevalence study of H. pylori infection in dyspeptic patients coming to Nepal Medical College Teaching Hospital, Jorpati, Kathmandu.

Helicobacter pylori (H. pylori) is one of the most common human infections worldwide particularly in the developing countries. It has been established as etiology of chronic gastritis and peptic ulcer disease, gastric adenocarcinoma and mucosal associated lymphoid tissue lymphoma (MALT). During this decade, there have been some reports showing a decline in global prevalence of H. pylori infection and peptic diseases including many Asian countries. Hence to determine prevalence of Helicobacter pylori infection in dyspeptic patients, this descriptive, non-interventional study was carried out at the Endoscopy sub-unit of the Surgery Department from April 2011 to February 2012. Three hundred nineteen dyspeptic patients (Male 161 and female 152) with a mean age of 20.12 years were examined for the presence of H. pylori infection by histology staining. The prevalence of H. pylori infection was 50.47%. The most common endoscopic findings was gastritis (47.6%) followed by normal findings 57 (17.87%). A total of 8.47% of gastric Ulcer, oesophagitis 5.64% and gastric cancer 0.94% were detected. All three cases of gastric cancer were positive for H. pylori infection. Among gastritis, H. pylori was observed in 67 (44%) cases and 18 out of 57 (5.6%) of normal gastric mucosa showed H. pylori. The endoscopic findings such as gastritis, gastric ulcer, duodenal ulcer and gastro duodenal reflux are significantly associated with H. pyloric infection. The prevalence of H. pylori infection is still high in peptic diseases. H. pylori infection is significantly correlated with peptic ulcer diseases than with non-ulcer dyspepsia. Further studies are required to establish the H. pylori positive cases with that of other tests such as serological detection of anti H. pylori antibody by ELISA/ICT and culture to establish a diagnosis quickly without any invasive method and institute proper management thus reducing morbidity.

Study on responses after splenectomy for idiopathic thrombocytopenic purpura patients, Kathmandu, Nepal.

Idiopathic thrombocytopenic purpura (ITP) is an autoimmune disorder characterized by accelerated destruction of platelets due to the presence of platelet (Plt) auto antibodies and impaired production of platelets. Splenectomy is still the standard salvage therapy in cases refractory to corticosteroid therapy. Retrospectively we analyzed 34 patients with ITP that underwent splenectomy in the period May 2010 to March 2012 and have been followed for at least 12 months. All patients met the diagnostic criteria for ITP. The median age at diagnosis was 26 years (range: 14-55 years). Overall response rate to splenectomy after 1 year of follow up was 94.1%, with Complete response in 32 and no response or relapse in 2 (5.8%). Sex didn't influence the outcome after splenectomy in our group of patients. Only preoperative response to steroids (P value = 0.018) and post-operative platelet count (P value = 0.013) were found to be significant statistically. Splenectomy considered as safe and effective treatment for patients with ITP who failed to respond to firs-line treatment with corticosteroids. Management of patients who do not respond or relapse after splenectomy represent an important problem for further treatment due to low response rate to other treatment options.

Outcome analysis of breast cancer patients treated at Nepal Medical College.

Breast carcinoma is second most common malignancy among women in Nepal and is also still a killer carcinoma in our context. We are encountering with more cases of breast cancer, may be due to increase number of cases because of life style modification or due to more diagnostic facilities available in the country. Yet we most often encounter more advanced stage of breast carcinoma. In our study we had total of 21 patients who suffered from breast carcinoma. Among those patients most were elderly with mean age of 54.33 +/- 11.25 years. Among 21 patients, 13 patients were either of locally advanced type or with advanced breast carcinoma with metastasis. In our institution these patients were offered evidence based treatment as per their requirement. Since most of these patients are unaware of self breast examination and hence presented lately. Even though they were managed properly, 1 patient had local recurrence and 4 patients later presented with distant metastasis.

Inguinal herniotomy in children: a one year survey at Nepal Medical College Teaching Hospital.

This was a prospective study done at Nepal Medical College Teaching Hospital from July 2008 to June 2009 which covers our experience in inguinal herniotomy in children. Our study included 63inguinal hernia repairs in 61 children up to the age of 15 years. Out of 61 patients 2 had bilateral inguinal hernia and 59 had unilateral. Among 59 patients with unilateral hernias, 7 patients had emergency presentation. In children with unilateral hernias, it was found that it is more common at right side and regarding complication it is more common in emergency group. There were 5 recurrences and 5 wound infection among all patients.

The incidence of thyroid carcinoma in multinodular goiter: prospective study.

Thyroid carcinoma (TC) is a relatively rare tumour, but it represents the most frequent form of cancer of the endocrine glands. Epidemiologically ascertained risk factors are ionising radiation, the presence of thyroid adenoma and multinodular goiter (MNG). Multinodularity of goiter should no longer be considered an indicator of probable benign disease. A prospective analysis was performed on patients operated for multinodular Goiter at Nepal Medical College from January 2009 to November 2011, in order to establish the incidence of carcinoma. The results of this study, demonstrate that in 13.63 % of the patients operated for goiter, the presence of a carcinoma was noticed in the definitive histopathologic examination. Such incidence percentage of MNG is in accordance with the data reported in published reports. Thus, we conclude that the risk of malignancy in MNG has not to be underestimated, and that a dominant nodule in MNG should be valued as if it were a solitary nodule in an otherwise normal gland.